Glass. Book. COPYRIGHT DEPOSIT THE CHEMISTRY AND ANALYSIS OF DRUGS AND MEDICINES BY HENRY C. FULLER, B.S. In Charge of the Division of Drug and Food Products, The Institute of Industrial Research, Washington, D. C. NEW YORK JOHN WILEY & SONS, Inc. London: CHAPMAN & HALL, Limited 1920 "The use in this volume of certain portions of the text of the United States Pharmacopoeia is by virtue of permission received from the Board of Trustees of the United States Pharmacopoeial Convention. The said Board of Trustees is not responsible for any inaccuracy of quotation nor for any errors in the statement of quantities or percentage strengths." "Permission to use for comment parts of the text of the National Formulary, Fourth Edition, in this volume has been granted by the Committee on Publication by the authority of the Council of the American Pharmaceutical Association." Copyright, 1920, by HENRY C. FULLER * \ DEC 27 1920 ©CU604716 PRESS OF BRAUNWORTH L CO. BOOK MANUFACTURERS BROOKLYN, N. V. CONTENTS INTRODUCTION Part I GENERAL METHODS AND CRUDE DRUG ASSAYS CHAPTER I PAQB General Methods 1 CHAPTER II Crude Drug Assays 23 Part II ALKALOIDAL DRUGS, ALKALOIDS AND MEDICINALLY ALLIED SUBSTANCES CHAPTER III Definition and General Methods of Separation and Identification 71 CHAPTER IV Alkaloids Derived from Pyridin 82 CHAPTER V Alkaloids Derived from Pyrrolidin 100 CHAPTER VI Alkaloids Derived from Quinolin 149 CHAPTER VII Alkaloids Derived from Isoquinolin 183 iii IV CONTENTS CHAPTER VIII PAGE Alkaloids which Probably Contain a Pyridin Nucleus 250 CHAPTER IX Alkaloids with no Pyridin Nucleus and Those of Unknown Composition. 281 Part III GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS CONTAINING PRINCIPLES OTHER THAN ALKALOIDS CHAPTER X Glucosides 309 CHAPTER XI Purgative Drugs 360 CHAPTER XII Miscellaneous Acting Drugs 391 CHAPTER XIII Botanical Drugs 414 CHAPTER XIV Gums and Resins 460 Part IV ORGANIC SUBSTANCES OTHER THAN ALKALOIDS AND GLUCOSIDES CHAPTER XV Hydrocarbons — Alcohols — Ethers 517 CHAPTER XVI Aldehydes and Ketones 570 CHAPTER XVII Organic Acids — Aliphatic Series 624 CONTENTS V CHAPTER XVIII PAGE Organic Acids — Aromatic Series 658 CHAPTER XIX Ethereal Salts — Phenols 727 CHAPTER XX Synthetic Organic Nitrogen Compounds, Amines, Diamines, Amides 790 CHAPTER XXI Anilides and Phenetidines 83 1 CHAPTER XXII Organic Arsenic Compounds 873 CHAPTER XXIII Proteins and Digestives 884 CHAPTER XXIV Oils 913 Part V INORGANIC SECTION CHAPTER XXV Methods of Identification 937 CHAPTER XXVI Non-Metals and Their Compounds 940 CHAPTER XXVII Metals and their Compounds 970 Tables 1C33 Index 1050 INTRODUCTION Whoever has taken up an investigation of drugs and medicines, whether in the line of analysis or research, must have been impressed with the fact that there has been no individual publication dealing with analytical procedures applicable to the subject as a whole. The analyst could turn to the Pharmacopoeia and National Formulary for methods of assaying and testing the official drugs, and to other works such as Autenreith and Warren's " Detection of Poisons," " New and Non-Official Remedies " published by the American Medical Association, and the publications of the Association of Official Agricultural Chemists, where he would find information and perhaps methods applicable to certain classes of drugs and medicinal agents, but there has been no general analytical work embracing this branch of chemistry. The food analyst could turn to Leach's " Food Inspection and Analysis," and there find complete the latest methods for solving his analytical problems, but the drug analyst was less fortunate, and when presented with a problem of analysis outside the usual run of drug assaying, there was involved a long search through the available text books, technical journals, and official publications before a satisfactory procedure was found, if any existed. The work in hand has been published in order to remedy this situation. The material for it has been collected during the past seventeen years, and has been arranged in a way which it is believed will be found con- venient to the worker who is handling miscellaneous analytical investi- gations. Problems of analysis of drugs and medicines are many and varied. Those most frequently met with may be grouped as follows: The assaying of individual crude drugs and medicinal chemicals; The analysis of mixtures for one or more essential ingredients; The determination of the character and amounts of the compo- nents of a medicine, either for purposes of duplication, or for the basis of a court proceeding; The testing of individual substances for their identity and purity; The separation and identification of the hitherto unknown consti- tuents of crude drugs; The identification of small quantities of toxic principles. viii INTRODUCTION The subject matter in this work has been arranged in general in accord- ance with its chemical relationship, although in that portion dealing with organic substances the sequence in which one group follows another in theoretical chemistry has not been followed. In the groups themselves some substances have been' discussed simultaneously with those with which they are medicinally allied, even though they may not be related to them chemically. For instance, it is obviously more comprehensive to include all of the local anesthetics under the chapter on "Cocain" than to scatter them through the various groups of organic compounds under which they would fall because of their chemical relationship. By far the larger proportion of the number of the individual drugs and remedial agents belong to the class of organic substances. In the general arrangement the natural drugs and their derivatives have been considered first, then follows the individual organic substances, including most of the so-called " synthetics," and lastly the inorganic drugs. Those characteristics of the different substances valuable for their analytical significance have been detailed, many new, important and hith- erto obscure reactions have been recorded, and wherever reliable quanti- tative methods of determination and separation could be found, they have been described. In the treatment of the individual drugs and medicinal agents con- siderable space has been devoted to detailing the character of the remedies in which they commonly occur, and the combinations usually found in practice. Knowledge of this kind is of great aid to the analyst, and will often save a vast amount of unnecessary labor when he is working with an unknown mixture. As a matter of fact, if the analyst has at his dis- posal the latest catalogues of the large pharmaceutical houses, he will often obtain valuable assistance in arriving at the probable composition of a remedy, once he knows for what purpose it is to be used, and the identity of one or more of the essential ingredients. A section of the work has been devoted to some general determi- nations which are often necessary in analyzing galenicals, and for the con- venience of the drug assayist a section has been given over to drug assays in which are assembled all of the reliable representative methods available for analyzing crude drugs. In the various groups, especially in the organic section, references will be found to many substances which are not used medicinally, but which, by reason of their properties, are closely related to those having direct connection with the general subject. These individuals have been noted because it often happens, especially when working up a court case, that the chemist finds it necessary to refresh his knowledge con- cerning the members of a given series of organic substances other than the particular one which will figure in the case. INTRODUCTION IX No attempt has been made in general to go into the description of the botanical drugs from the standpoint of the pharmacognosist. To have consumed space with their descriptions would only have duplicated such special works on the subject, as Kraemer's " Botany and Pharma- cognosy." Data for this work have been drawn freely from authorities who have handled special subjects, and in each instance due reference and credit have been given. Much material has appeared in the literature during the past twenty years ; practically all of this has been reviewed, and that which was reliable and essential has been quoted. The assembling and classification of all this material, and the testing out of the methods, have involved considerable research, but it is believed that the object in view justified the endeavor, and that there has been evolved a work which will be greatly appreciated by those concerned with the inspection and analysis of drugs and medicines. Part I GENERAL METHODS AND CRUDE DRUG ASSAYS CHAPTER I GENERAL METHODS It is almost a waste of time to begin the quantitative analysis of a medicinal product until one has determined by carefully performed quali- tative investigation the nature of the substances present. In food analysis one can often determine the percentages of moisture, ash, nitrogen, starch, rotatory power before and after inversion, the presence or absence of pre- servatives and then interpret his results. Not so with drug analysis. Except in cases where the worker has to deal with extracts or substances containing but one ingredient, each preparation offers a problem by itself and often a dozen samples containing the same single ingredient, put out by a dozen different firms, will require different procedures owing to the difference in pharmaceutical make up. There are, however, certain general tests which must be applied to large groups of substances regardless of their composition, and for conven- ience they have been detailed at this point. In the cases of all liquid preparations, the specific gravity and alcohol should be estimated; in both liquids and solid medicinal agents the total non-volatile matter, ash, and sugar determined as a guide and check in arriving at the final composition, and the presence and amount of arsenic should be established. SPECIFIC GRAVITY This datum should be determined with an accurate pycnometer at a convenient temperature, such as 15.6° or 20° C. The result is an aid in the future determinations and obviates the weighing out of the sample if the measurements are made in accurately graduated flasks or pipettes. 2 GENERAL METHODS AND CRUDE DRUG ASSAYS ALCOHOL If the sample contains but negligible quantities of volatile matter other than alcohol and water, the alcohol may be estimated by simple distil- lation and determining the amount from the specific gravity of the dis- tillate, which should be so regulated that it does not contain over 50 per cent of alcohol and for satisfactory results never more than 35 per cent, hence if the sample is suspected of containing over 50 per cent alcohol, it should be distilled and made up to twice its original volume. If the sample is acid and contains no free iodine, it sould be neutral- ized with alkali and the distillate should be subsequently tested with litmus to determine its alkalinity. In certain instances, when ammonium salts occur in mixtures containing alkaloids or alkaloid-bearing drugs, free ammonia will be disengaged, and the distillate must be neutralized with sulphuric or phosphoric acid and again distilled. If iodine be present, it can be fixed with sodium thiosulphate. The determination is made by filling to the mark an accurately gradu- ated 50-mil flask, observing the proper temperature at which the flask is graduated, and pouring the contents into the retort flask of a distilling apparatus; the flask is washed out with three portions of 15 to 20 mils of distilled water, pouring the water into the flask of the distilling appa- ratus. Distillation is then conducted into the flask in which the original measurement was made or one of double its capacity, having it surrounded with ice water, until it is about three-quarters full, when it is removed and made up with distilled water to volume, the temperature being adjusted to that at which the original measurement was made. The specific gravity is determined at 15.6° or 20° C. by means of an accurate pycnometer, and from the figure obtained the alcoholic percentage determined from the standard table. When working with sarsaparilla, soapwort, or other solutions con- taining saponin-like bodies which produce frothing, a small amount of paraffin or petrolatum should be added to prevent the liquid from bubbling over into the receiver. With some mixtures it may prove more satis- factory to distill without attempting to prevent some of the bubbles from going over and then to conduct a second distillation. The presence of g ycerin has no effect on the accuracy of the method, for this substance does not come over with the distillate unless the con- centration of the glycerin solution is over 70 per cent. Acetanilid will distill in small amounts, but its presence in the distillate does not affect the accuracy of the method. If volatile oils, chloroform, ether, camphor, or like substances are present, the method must be modified by the principle advanced by Thorpe and Holmes 1 using petroleum ether and sodium chloride to salt i J. Chem. Soc, 1903, 83, 313. GENERAL METHODS ALCOHOLOMETRIC TABLE Temperature 15.56° C. Percentage by Volume Percentage by Weight Per Cent Vol. Corre- sponding Per Cent Weight Sp. Gr. App.* in Air 15.56° 15.56° Corr.f of Sp. Gr. for Barometer (100 mm.) Frac- tional^ Per Cent Per Cent Wt. Corre- sponding Per Cent Volume Sp. Gr. App.* in Air 15.56° 15.56° Corr.f of Sp. Gr. for Barometer (100 mm.) Frac- tional! Per Cent §o 0.000 1.00000 0.000000 0.0667 0.000 1.00000 0.000000 0.0532 1 0.795 0.99850 0.000000 0.0680 1 1.257 0.99812 0.000000 0.0543 2 1.593 0.99703 0.000000 0.0690 2 2.510 0.99628 0.000000 0.0565 3 2.392 0.99558 0.000001 0.0714 3 3.758 0.99451 0.000001 0.0588 4 3.194 0.99418 0.000001 0.0730 4 5.002 0.99281 0.000001 0.0610 5 3.998 0.99281 0.000001 0.0746 5 6.243 0.99117 0.000001 0.0641 6 4.804 0.99149 0.000001 0.0781 6 7.479 0.98961 0.000001 0.0671 7 5.612 0.99021 0.000001 0.0813 7 8.712 0.98812 . 000002 0.0680 8 6.422 0.98898 0.000002 0.0833 8 9.943 0.98665 0.000002 0.0700 9 7.234 0.98778 0.000002 0.0840 9 11.169 0.98523 . 000002 0.0719 10 8.047 0.98659 0.000002 0.0855 10 12.393 0.983S4 0.000002 0.0746 11 8.862 0.98542 0.000002 0.0877 11 13.613 0.98351 0.000003 0.0769 12 9.679 0.98428 0.000002 0.0901 12 14.832 0.98120 0.000003 0.0775 13 10.497 0.98317 0.000003 0.0917 13 16.047 0.97991 0.000003 0.0800 14 11.317 0.98208 0.000003 0.0943 14 17.259 97866 0.000003 0.0820 15 12.138 0.98102 0.000003 0.0943 15 18.469 0.97744 0.000004 0.0840 16 12.961 0.97996 0.000003 0.0962 16 19.676 0.97625 0.000004 0.0833 17 13.786 0.97892 0.000003 0.0990 17 20.880 0.97505 0.000004 0.0826 18 14.612 0.97791 0.000004 0.1000 18 22.081 0.97384 0.000004 0.0813 19 15.440 0.97691 0.000004 . 1020 19 23.278 0.97261 0.000004 0.0806 20 16.269 0.97593 0.000004 0.1000 20 24.472 0.97137 . 000005 0.0794 21 17.100 0.97493 0.000004 0.0990 21 25.662 0.97011 0.000005 0.0781 22 17.933 0.97392 0.000004 0.0980 22 26.849 0.96883 . 000005 0.0769 23 18.768 0.97290 0.000004 0.0962 23 28.032 0.96753 0.000005 0.0752 24 19.604 0.97186 0.000005 0.0952 24 29.210 0.96620 0.000005 0.0740 25 20.443 0.97081 0.000005 0.0943 25 30.388 0.96485 0.00C006 0.0719 26 21.285 0.96974 0.000005 0.0926 26 31.555 0.96346 0.000006 0.0694 27 22.127 0.96866 0.000005 0.0909 27 32.719 0.96202 0.000006 0.0667 28 22.973 0.96756 0.000005 0.0893 28 33.879 0.96052 0.000006 0.0649 29 23.820 0.96644 0.000005 0.0877 29 35.033 0.95898 0.000007 0.0633 30 24.670 0.96530 0.000005 0.0862 30 36.181 0.95740 0.000007 0.0613 GENERAL METHODS AND CRUDE DRUG ASSAYS ALCOHOLOMETRIC TABLE— Continued Percentage by Volume Percentage bt Weight Per Cenl Vol. Corre- sponding Per Cent Weight Sp. Gr. App.* in Air 15.56° 15.56° Corr.t of Sp. Gr. for Barometei (100 mm.) Frac- tional:): Per Cent Per Cen1 Wt. Corre- sponding Per Cent Volume Sp. Gr. App.* in Air 15.56° 15.56° Corr.t of Sp. Gr. for Barometer (100 mm.) Frac- tional^ Per Cent 31 25.524 0.96414 o.oooooe 0.0820 31 37.323 0.95577 0.000007 0.0595 32 26.382 0.96292 0.000006 0.0787 32 38.459 0.95408 . 000007 0.0578 33 27.242 0.96165 0.000006 0.0775 33 39.590 0.95236 0.000007 0.0565 34 28.104 0.96036 0.000006 0.0752 34 40.716 0.95058 000008 0.0556 35 28.971 0.95903 0.000006 0.0725 35 41.832 0.94878 0.000008 0.0546 36 29.842 0.95765 0.000007 0.0704 36 42.944 0.94696 0.000008 0.0538 37 30.717 0.95623 0.000007 0.0685 37 44.050 0.94509 . 000009 0.0521 38 31.596 0.95477 0.000007 0.0668 38 45 . 149 0.94317 0.000009 0.0515 39 32.478 0.95326 . 000007 0.0649 39 46.242 0.94123 0.000009 0.0508 40 33.364 0.95172 0.000007 0.0633 40 47.328 0.93926 . 000010 0.0498 41 34.254 0.95014 0.000008 0.0617 41 48.407 0.93725 0.000010 0.0488 42 35 . 150 0.94852 . 000008 0.0600 42 49.480 0.93520 0.000010 0.0485 43 36.050 0.94687 0.000008 0.0588 43 50.545 0.93312 0.000011 0.0476 44 36.955 0.94517 0.000009 0.0578 44 51.605 0.93102 0.000011 0.0474 45 37.865 0.94344 0.000009 0.0565 45 52.658 0.92891 0.000011 0.0469 46 38.778 0.94167 . 000009 0.0552 46 53.705 0.92678 0.000012 0.0467 47 39.697 0.93986 0.000009 0.0541 47 54.746 0.92464 0.000012 0.0461 48 40.622 0.93801 . 000010 0.0526 48 55.780 0.92247 0.000012 0.0461 49 41.551 0.93611 0.000010 0.0518 49 56.808 0.92030 0.000013 0.0457 50 42.487 0.93418 0.000010 0.0510 50 57.830 0.91811 0.000013 0.0455 51 43.428 0.93222 0.000011 0.0503 51 58.844 0.91591 0.000013 0.0446 52 44.374 0.93023 0.000011 0.0498 52 59.851 0.91367 0.000014 0.0444 53 45.326 0.92822 0.000011 0.0488 53 60.854 0.91142 0.000014 0.0444 54 46.283 0.92617 . 000012 0.0483 54 61.850 0.90917 0.000014 0.0442 55 47.245 0.92410 . 000012 0.0478 55 62.837 0.90691 . 000015 0.0441 56 48.214 0.92201 0.000012 0.0474 56 63.820 0.90464 0.000015 0.0441 57 49.187 0.91990 0.000013 0.0463 57 64.798 0.90237 0.000015 0.0441 58 50.167 0.91774 0.000013 0.0457 58 65.768 0.90010 0.000016 0.0437 59 51.154 0.91555 0.000013 0.0452 59 66.732 0.89781 . 000016 0.0435 60 52.147 0.91334 0.000014 0.0446 60 67.690 0.89551 0.000016 0.0433 61 53.146 0.91110 0.000014 0.0439 61 68.641 0.89320 0.000017 0.0431 62 54.152 0.90882 0.000014 0.0437 62 69.586 0.89088 0.000017 0.0431 63 55.165 0.90653 0.000015 Q.0435 63 70.523 0.88856 0.000017 0.0427 64 56.184 0.90423 0.000015 0.0429 64 71.455 0.88623 0.000018 0.0426 65 57.208 0.90190 0.000015 0.0426 65 72.380 0.88388 0.000018 0.0426 GENERAL METHODS ALCOHOLOMETRIC TABLE— Continued Percentage by Volume Percentage by Weight Per Cent Vol. Corre- sponding Per Cent Weight Sp. Gr. App.* in Air 15.56° 15.56° Corr.t of Sp. Gr. for Barometer (100 mm.) Frac- tionalj Per Cent Per Cent Wt. Corre- sponding Per Cent Volume Sp. Gr. App.* in Air 15.56° 15.56° Corr.t of Sp. Gr. for Barometer (100 mm. Frac- tional % Per Cent 66 58.241 0.89955 0.000016 0.0420 66 73.299 0.88153 0.000019 0.0426 67 59.279 0.89717 0.000016 0.0410 67 74.211 0.87918]0. 000019 0.0426 68 60.325 0.89477 0.000016 0.0408 68 75.117 0.87683 0.000019 0.0422 69 61.379 0.89232 0.000017 0.0407 69 76.016 0.87446 0.000020 0.0422 70 62.441 0.88986 0.000017 0.0403 70 76.909 0.87206 0.000020 0.0418 71 63.511 0.88738 0.000018 0.0395 71 77.794 0.86970 0.000021 0.0417 72 64.588 0.88485| 0.000018 0.0392 72 78.672 0.86730 0.000021 0.0417 73 65.674 0.88230 0.000019 0.0389 73 79.544 0.86490 0.000021 0.0417 74 66.768 0.87973 0.000019 0.0385 74 80.410 0.86250 0.000022 0.0413 75 67.870 0.87713 0.000019 0.0380 75 81.269 0.86008 0.000022 0.0413 76 68.982 0.87450 0.000020 0.0376 76 82.121 0.85766 0.000022 0.0413 77 70.102 0.87184 0.000020 0.0370 77 82.967 0.85524 0.000023 0.0412 78 71.234 0.86914 0.000021 0.0365 78 83.805 0.852810.000023 0.0403 79 72.375 0.86640 0.000021 0.0362 79 84.636 0.85033 0.000024 0.0408 80 73.526 0.86364 0.000021 0.0357 80 85.459 0.84788 0.000024 0.0403 81 74.686 0.86084 0.000022 0.0352 81 86.275 0.84540 0.000024 0.0402 82 75.858 0.85800 0.000022 0.0350 82 87.083 0.842910.000025 0.0402 83 77.039 0.85514 0.000023 0.0344 83 87.885 0.84042 0.000025 0.0398 84 78.233 0.85223 0.000023 0.0337 84 88.678 0.83791 0.000025 0.0394 85 79.441 0.84926 0.000024 0.0331 85 89.464 0.83537 0.000026 0.0392 86 80.662 0.84624 0.000024 0.0326 86 90.240 0.83282 0.000026 0.0391 87 81.897 0.84317 0.000025 0.0322 87 91.008 0.83026J 0.000027 0.0386 88 83 . 144 0.84006 0.000025 0.0314 88 91.766 0.82767 0.000027 0.0377 89 84.408 0.83688 0.000026 0.0307 89 92.517 0. 82502^. 000028 0.0380 90 85.689 0.83362 0.000026 0.0300 90 93.254 0.82239:0.000028 0.0372 91 86.989 0.83029 0.000027 0.0291 91 93.982 0.81970 0.000028 0.0367 92 88.310 0.82685 0.000027 0.0282 92 94.700 0.816970.000029 0.0362 93 89 . 652 0.82330 0.000028 0.0272 93 95.407 0.814210.000029 0.0358 94 91.025 0.81963 0.000028 0.0262 94 96.103 0.81142 0.000030 0.0353 95 92.423 0.81581 0.000029 0.0252 95 96.787 0.80859 0.000030 0.0348 96 93.851 0.81184 0.000030 0.0240 96 97.457 0.80572 . 000030 0.0342 97 95.315 0.80769 0.000030 0.0229 97 98.117 0.80280 0.000031 0.0334 98 96.820 0.80333 0.000031 0.0214 98 98.759 0.799810.000031 0.0328 99 98.381 0.79865 0.000031 0.0200 99 99.386 0.79676 0.000032 0.0322 100 100.000 0.79365,0.000032 100 100.000 0.79365 0.000032 6 GENERAL METHODS AND CRUDE DRUG ASSAYS out the volatile ingredients. Unless the mixture contains considerable fixed residue such as mineral salts, sugar, or drug extractive, the proced- ure can be carried out on the original sample, but if these are present in marked quantity a preliminary distillation should be made. Then the solution is transferred to a separator, diluted with water if necessary until the alcoholic content is not over 25 per cent, excess of solid sodium chloride added, and shaken out three times with about one-fourth its volume of low-boiling petroleum ether. The petroleum ether washings are collected in another separator, washed with saturated salt solution, the latter added to the main liquid and the whole distilled. NON-VOLATILE MATERIAL AND ASH The non-volatile material can often be determined in the residue remaining in the distilling flask from the alcohol determination unless it was necessary to manipulate the solution in some way before carrying out the distillation. In case this is not feasible 10-25 mils of the original sample are used for the determination, measurement being made with an accurate pipette or graduated flask, the sample washed into a small porcelain dish and evaporated over the steam bath until there is appar- ently no further diminution in volume, and then transferred to a drying oven and exposed to the heat of 100° C. for five hours. The dish should be cooled in a desiccator and weighed rapidly, no attempt being made to go beyond the third decimal, as most of these residues are hygroscopic. This method will give one an idea of the amount of non-volatile material present. The water will be practically all eliminated in this time, and while continued heating will cause a further loss in weight, it is due to the expulsion of other volatile substances, the breaking down of sugar, the gradual volatilization of glycerin, etc. In the case of some mixtures the determination of non-volatile material by this method will prove of little value; for instance, if one is dealing with a headache mixture con- taining acetanilid, the latter will volatilize. Such preparations, after the water is nearly all driven off on the steam bath, should be allowed to dry for ten or twelve hours in a vacuum desiccator over sulphuric acid or calcium chloride. ASH After weighing the residue in the above determination, it should be carefully burned and the ash weighed, the result giving an approxi- mate value of the quantity of mineral salts. If the ash is heavily impreg- nated with resistant carbon it can be leached with dilute acetic acid, the solution filtered, evaporated, and the filter paper and carbon returned to the dish and the whole burned a second time. GENERAL METHODS 7 SUGAR Sucrose or cane sugar enters into the composition of a large variety of medicinal substances, including elixirs, wines, syrups, cordials, pills, tablets, lozenges, pastilles, granular preparations and some powders. Lactose or milk sugar occurs in powders. Honey is often used. Com- mercial glucose is present in pill and tablet mixtures and to some extent probably in liquid preparations. Invert sugar will be present to some extent where sucrose has been hydrolyzed by acid. True glucose as a decomposition product of glucosides, as well as other less common sugars from the same sources will be found. The analyst will be chiefly con- cerned with determining the sugar which is present as one of the chief bulk ingredients. The polariscopic methods for the estimation of sugar may be employed in the case of those mixtures which are free from caramel or contain sub- stances which are readily removed by lead acetate, and by checking the determination by a copper reduction before and after inversion the amount can be obtained with a satisfactory degree of accuracy. This quali- fication must be made because there are many substances other than sugar which will affect the polarization and copper reduction to a greater or less extent, and their presence will, of course, have been established by a previous qualitative examination. Sucrose 1 Dissolve the normal weight (26 grams) of the substance in water, add basic lead acetate carefully, avoiding any excess, then 1-2 mils of alu- mina cream, shake, and dilute to 100 mils, filter, rejecting the first 20 mils of the filtrate, cover the filter with a watch glass and, when suffi- cient filtrate is collected, polarize in a 200-mm. tube. The reading so obtained is the direct reading (P of formula given below) or polarization before inversion. For the invert reading, remove the lead from the solu- tion either (1) by adding anhydrous potassium oxalate, a little at a time, to the remaining solution, avoiding an excess and removing the precipi- tated lead by filtration; or, (2) by adding anhydrous sodium carbonate under the same conditions. Introduce 50 mils of the lead-free filtrate into a 100-mil flask (if sodium carbonate was used for removing the lead, neutralize carefully the excess of sodium carbonate with a few drops of dilute hydrochloric acid) and add 25 mils of water. Then add, little by little, while rotating the flask, 5 mils of hydrochloric acid (sp. gr. 1.20). Heat the flask after mixing, in a water-bath kept at 70° C. in 2\ to 3 minutes. Maintain a temperature of as nearly 69° C. as possible for 7 to 1\ minutes, making the total time of heating ten minutes. Remove the flask and cool the contents rapidly to 20° C. and dilute to 100 mils. 1 By Polarization before and after Inversion with Hydrochloric Acid. — A.O.A.C. 8 GENERAL METHODS AND CRUDE DRUG ASSAYS Polarize this solution in a tube provided with a lateral branch and a water jacket, maintaining a temperature of 20° C. . This reading must be multi- plied by 2 to obtain the invert reading. If it is necessary to work at a temperature other than 20° C, which is allowable within narrow limits, the volumes must be completed and both direct and invert polariza- tions must be made at exactly the same temperature. The inversion may also be accomplished as follows: (1) To 50 mils of the clarified solution, freed from lead, add 5 mils of hydrochloric acid (sp. gr. 1.20) and set aside for twenty-four hours at a temperature not below 20° C; or, (2) if the temperature be above 25° C. set aside for ten hours. Make up to 100 mils at 20° C. and polarize as directed above. Calculate sucrose by one of the following formulas: For Substances in which the Invert Solution Contains more than 12 Grams of Invert Sugar per 100 Mils. — The following formula is to be used when substances like raw sugars are polarized: 5 _ 100 (P-I) T 142.66-^ -j in which S = per cent of sucrose ; P = direct reading normal solution ; I = invert reading normal solution ; T = temperature at which readings are made. For Substances in which the Concentration of the Invert Solution is Less than 12 Grams per 100 Mils. — The following formula, which takes into account the concentration of the sugar in solution, should be used in all other cases. s= 100 (P=I) . 142.66 = ^ = 0.0065(142. 66 = ^= (P=I)) in which S = per cent of sucrose ; P = direct reading normal solution ; I = invert reading normal solution; T*= temperature. TOTAL SUGARS AND SUCROSE BY COPPER REDUCTION For the copper reduction, the procedure of Munson and Walker gives the greatest satisfaction. The reagents consist of copper sulphate 34.6 grams to 500 mils; and alkaline tartrate, 173 grams Rochelle Salts, and 50 grams sodium hydrate to 500 mils. A determination should be made on the sample directly, then the amount given by inversion ascertained, GENERAL METHODS 9 and from the figures the amount due to sucrose may be calculated. The quantity of the sample to be taken cannot be stated by any hard-and- fast rule, and the worker should make a few prehminary tests before running the actual determination. For liquids 10 to 25 mils will be suf- ficient, and for solids 10 grams will usually suffice. After the sample has been accurately measured or weighed, it is intro- duced into a 100-mil graduated flask, diluted with water, precipitated with an excess of neutral lead acetate and made up to volume. A 25-mil aliquot is then precipitated with potassium oxalate, diluted to a definite volume without filtering, and the reducing sugars determined in a small portion of the clear liquid. Tenmils, or a sufficient quantity of this diluted solution are measured out with a pipette or burette and added to a mix- ture of 25 mils each of the copper and tartrate solution in a 400-mil beaker, 40 mils of water are added, the mixture brought to a boil as rapidly as possible, and boiled for two minutes. The cuprous oxide is then fil- tered onto an asbestos felt in a porcelain Gooch crucible, using suction, washed with warm water, dried with alcohol and ether, placed in an oven at 100° C. for half an hour and then cooled and weighed. For the sucrose determination a 50-mil aliquot of the original 100-mil solution of the sample is precipitated with potassium oxalate, filtered and a 25-mil portion of the filtrate inverted with hydrochloric acid as directed under "Sucrose" This liquid is then made up to volume and the total reduction determined. The number of milligrams of copper reduced by a given amount of sugar differs when sucrose is present and when it is absent. In the sugar table there are two columns, one for a mixture of invert sugar and sucrose in the case of about .4 gram total sugar and another in case of about 2 grams; in addition there is a column for invert sugar alone. The factor for sucrose is 0.95. As has been stated above, there are a number of substances other than the well-known reducing sugars which throw out cuprous oxide from an alkaline copper solution, and for the benefit of the worker the follow- ing list has been compiled. It includes most of the individuals with which the worker will meet. Acetaldehyde and all other aldehydes of the acetic series. Arabinose Gallotannic acid Mannitose Arsenous acid Glycosuric acid Pectinose Chloral Glycuronic acid Pyrogalhc acid Chloroform Glycyrrhizin Resorcinol Dextrose Iso-dulcite Rhamnose Eucalyptose Lactose Sorbinose Formaldehyde Levulose Trichlor acetic acid Formic acid Maltose Zylose Galactose 10 GENERAL METHODS AND CRUDE DRUG ASSAYS MUNSON AND WALKER'S TABLE For calculating dextrose, invert sugar alone, invert sugar in the presence of sucrose (0.4 gram and 2 grams total sugar), lactose (two forms), and maltose (anhydrous and crystallized). [Expressed in milligrams.] o o> Invert Sugar and Sucrose Lactose Maltose q 3 o tn O o 3 3 o 3 u "3 c 15 c c 7° 6 3 3 3 GO H o w w C CD 3 O (4 m o t-c 8 u CO -_ S =3 e3 M 1 q 6 S3 1 GO 3 O ft 3 ft ft o 0) > C O 3 2 3 CJOQ ffl £ W w ft 3 o o Q © 03 i 6 6 6 o 10 8.9 4.0 4.5 1.6 3.8 4.0 5.9 6.2 10 11 9.8 4.5 5.0 2.1 4.5 4.7 6.7 7.0 11 12 10.7 4.9 5.4 2 5 5.1 5.4 7.5 7.9 12 13 11.5 5.3 5.8 3.0 5.8 6.1 8.3 8.7 13 14 12.4 5.7 6.3 3.4 6.4 6.8 9.1 9.5 14 15 13.3 6.2 6.7 3.9 7.! 7.5 9.9 10.4 15 16 14.2 6.6 7.2 4.3 7.8 8.2 10.6 11.2 16 17 15.1 7.0 7.6 4 8 8.4 8.9 11.4 12.0 17 18 16.0 7.5 8.1 5.2 9 1 9.5 12.2 12.9 18 19 16.9 7.9 8.5 5.7 9.7 10.2 13.0 13.7 19 20 17.8 8.3 8.9 6.1 10.4 10.9 13.8 14.6 20 • 21 18.7 8.7 9.4 6.6 11.0 11.6 14.6 15.4 21 22 19.5 9.2 9.8 7.0 11.7 12.3 15.4 16.2 22 23 20.4 9.6 10.3 7.5 12.3 13.0 16.2 17.1 23 24 21.3 10.0 10.7 7.9 13.0 13.7 17.0 17.9 24 25 22.2 10.5 11.2 8.4 13.7 14.4 17.8 18.7 25 26 23.1 10.9 11.6 8.8 14.3 15.1 18.6 19.6 26 27 24.0 11.3 12.0 9.3 15.0 15.8 19.4 20.4 27 28 24.9 11.8 12.5 9.7 15.6 16.5 20.2 21.2 28 29 25.8 12.2 12.9 10.2 16.3 17.1 21.0 22.1 29 30 26.6 12.6 13.4 10.7 4.3 16.9 17.8 21.8 22.9 30 31 27.5 13.1 .13.8 11.1 4.7 17.6 18.5 22.6 23.7 31 32 28.4 13.5 14.3 11.6 5 2 18.3 19.2 23.3 24.6 32 33 29.3 13.9 14.7 12.0 5.6 18.9 19.9 24.1 25.4 33 34 30.2 14.3 15.2 12.5 6.1 19.6 20.6 24.9 26.2 34 35 31.1 14.8 15.6 12.9 6.5 20.2 21.3 25.7 27.1 35 36 32.0 15.2 16.1 13.4 7.0 20.9 22 26.5 27.9 36 37 32.9 15.6 16.5 13.8 7.4 21.5 22.7 27.3 28.7 37 38 33.8 16.1 16.9 14.3 7.9 22.2 23.4 28.1 29.6 38 39 34.6 16.5 17.4 14.7 8.4 22.8 24.1 28.9 30.4 39 40 35.5 16.9 17.8 15.2 8.8 23.5 24.8 29.7 31.3 40 41 36.4 17.4 18.3 15.6 9.3 24.2 25.4 30.5 32.1 41 42 37.3 17.8 18.7 16.1 9.7 24.8 26.1 31.3 32.9 42 43 38.2 18.2 19.2 16.6 10.2 25.5 26.8 32.1 33.8 43 44 39.1 18.7 19.6 17.0 10.7 26.1 27.5 32.9 34.6 44 45 40.0 19.1 20.1 17.5 11.1 26.8 28.2 33.7 35.4 45 46 40.9 19.6 20.5 17.9 11.6 27.4 28.9 34.4 36.3 46 47 41.7 20.0 21.0 18.4 12.0 28.1 29.6 35.2 37.1 47 48 42.6 20.4 21.4 18.8 12.5 28.7 30.3 36.0 37.9 48 49 43.5 20.9 21.9 19.3 12.9 29.4 31.0 36.8 38.8 49 50 44.4 21.3 22.3 19.7 13.4 30.1 31.7 37.6 39.6 50 51 45.3 21.7 22.8 20.2 13.9 30.7 32.4 38.4 40.4 51 52 46.2 22.2 23.2 20.7 14.3 31.4 33.0 39.2 41.3 52 53 47.1 22.6 23.7 21.1 14.8 32.1 33.7 40.0 42.1 53 54 48.0 23.0 24.1 21.6 15.2 32.7 34.4 40.8 42.9 54 55 48.9 23.5 24.6 22.0 15.7 33.4 35.1 41.6 43.8 55 56 49.7 23.9 25.0 22.5 16.2 34.0 35.8 42.4 44.6 56 57 50.6 24.3 25.5 22.9 16.6 34.7 36.5 43.2 45.4 57 58 51.5 24.8 25.9 23.4 17.1 35.4 37.2 44.0 46.3 58 59 52.4 25.2 26.4 23.9 17.5 36.0 37.9 44.8 47.1 59 60 53.3 25.6 26.8 24. ?! 18.0 36.7 38.6 45.6 48.0 60 61 54.2 26.1 27.3 24. 8 18.5 37.3 39.3 46.3 48.8 61 62 55. 1 26.5 27.7 25,2 18 9 38.0 40.0 47.1 49.6 62 63 56.0 27.0 28.2 25.7 1 19 4 38.6 40.7 47.9 50.5 63 64 56.8 27.4 28.6 26.2 1 19.8 39.3 41.4 48 7 51.3 64 GENERAL METHODS 11 MUNSON AND WALKER'S TABLE— Continued [Expressed in milligrams.] § « Invert Sugar and Sucrose Lactose Maltose O 3 o 3 o o o J3 "eS _ 45 '3 o 3 2, M 3 W O c3 O O 3 '3 O 5 u a c3 c3 S «4 6 o 6 O m 3 o a O 3 2 3 000 W 1 w E a o O Q © iM 6 6 6 6 O 65 57.7 27.8 29.1 26.6 20.3 40.0 42.1 49.5 52.1 65 66 . 58.6 28.3 29.5 27.1 20.8 40.6 42.8 50.3 53.0 66 67 59.5 28.7 30.1 27.5 21.2 41.3 43.5 51.1 53.8 67 68 60.4 29.2 30.4 28.0 21.7 41.9 44.2 51.9 54.6 68 69 61.3 29.6 30.9 28.5 22.2 42.6 44.8 52.7 55.5 69 70 62.2 30.0 31.3 28.9 22.6 43.3 45.5 53.5 56.3 70 71 63.1 30.5 31.8 29.4 23.1 43.9 46.2 54.3 57.1 71 72 64.0 30.9 32.3 29.8 23.5 44.6 46.9 55.1 58.0 72 73 64.8 31.4 32.7 30.3 24.0 45.2 47.6 55.9 58.8 73 74 65.7 31.8 33.2 30.8 24.5 45.9 48.3 56.7 59.6 74 75 66 6 32.2 33.6 31.2 24.9 46.6 49.0 57.5 60.5 75 76 67.5 32.7 34.1 31.7 25.4 47.2 49.7 58.2 61.3 76 77 68.4 33.1 34.5 32.1 25.9 47.9 50.4 59.0 62.1 77 78 69.3 33.6 35.0 32.6 26.3 48.5 51.1 59.8 63.0 78 79 70.2 34.0 35.4 33.1 26.8 49.2 51.8 60.6 63.8 79 80 71.1 34.4 35.9 33.5 27.3 49.9 52.5 61.4 64.6 80 81 71.9 34.9 36.3 34.0 27.7 50.5 53.2 62.2 65.5 81 82 72.8 35.3 36.8 34.5 28.2 51.2 53.9 63.0 66.3 82 83 73.7 35.8 37.3 34.9 28.6 51.8 54.6 63.8 67 1 83 84 74.6 36.2 37.7 35.4 29.1 52.5 55.3 64,6 68.0 84 85 75.5 36.7 38.2 35.8 29.6 53.1 56.0 65.4 68.8 85 86 76.4 37.1 38.6 36.3 30.0 53.8 56.6 66.2 69.7 86 87 77.3 37.5 39.1 36.8 30.5 54.5 57 3 67.0 70.5 87 88 78.2 38.0 39.5 37.2 31.0 55.1 58.0 67.8 71.3 88 89 79.1 38.4 40.0 37.7 31.4 55.8 58.7 68.5 72.2 89 90 79.9 38.9 40.4 38.2 31.9 56.4 59.4 69.3 73.0 90 91 80.8 39.3 40.9 38.6 32.4 57.1 60.1 70.1 73.8 91 92 81.7 39.8 41.4 39.1 32.8 57.8 60.8 70 9 74.7 92 93 82.6 40.2 41.8 39.6 33.3 58.4 61.5 71.7 75.5 93 94 83.5 40.6 42.3 40.0 33.8 59.1 62.2 72.5 76.3 94 95 84.4 41.1 42.7 40.5 34.2 59.7 62.9 73.3 77.2 95 96 85.3 41.5 43.2 41.0 34.7 60.4 63.6 74.1 78.0 96 97 86.2 42.0 43.7 41.4 35.2 61.1 64.3 74.9 78.8 97 98 87.1 42.4 44.1 41.9 35.6 61.7 65.0 75.7 79.7 98 99 87.9 42.9 44.6 42.4 36.1 62.4 65.7 76.5 80.5 99 100 88.8 43.3 45.0 42.8 36.6 63.0 66.4 77.3 81.3 100 101 89.7 43.8 45.5 43.3 37.0 63.7 67.1 78.1 82.2 101 102 90.6 44.2 46.0 43.8 37.5 64.4 67.8 78.8 83.0 102 103 91.5 44.7 46.4 44.2 38.0 65.0 68.5 79.6 83.8 103 104 92.4 45.1 46.9 44.7 38.5 65.7 69.1 80.4 84.7 104 105 93.3 45.5 47.3 V 45.2 38.9 66.4 69.8 81.2 85.5 105 106 94.2 46.0 47.8 45.6 39.4 67.0 70.5 82.0 86.3 106 107 95.0 46.4 48.3 46.1 39.9 67.7 71.2 82.8 87.2 107 108 95.9 46.9 48.7 46.6 40.3 68.3 71.9 83.6 88.0 108 109 96.8 47.3 49.2 47.0 40.8 69.0 72.6 84.4 88.8 109 110 97.7 47.8 49.6 47.5 41.3 69.7 73.3 85.2 89.7 110 111 98.6 48.2 50.1 48.0 41.7 70.3 74 86 90.5 111 112 99.5 48.7 50.6 48.4 42.2 71.0 74 7 86.8 91.3 112 113 100.4 49.1 51.0 48.9 42.7 •71.6 75.4 87.6 92.2 113 114 101 . 3 49.6 51.5 49.4 43.2 72.3 76.1 88.4 93.0 114 115 102.2 50.0 51.9 49.8 43.6 73.0 76.8 89.2 93.9 115 116 103.0 50.5 52.4 50.3 44.1 73.6 77.5 90.0 94.7 116 117 103.9 50.9 52.9 50.8 44.6 74.3 78.2 90.7 95.5 117 118 104.8 51.4 53.3 51.2 45.0 75.0 78.9 91.5 96.4 118 119 105.7 51.8 53.8 51.7 45.5 75.6 79.6 92.3. 97.2 119 12 GENERAL METHODS AND CRUDE DRUG ASSAYS MUNSON AND WALKER'S TABLE— Continued [Expressed in milligrams.] 6 'S' Invert Sugar and Sucrose Lactose Mal rosE 6 B o 3 O o 9 u "3 "o "s3 O O 12 o o 2- c3 3 H o W ffi O 3 to O m e8 rt £ =3 d 6 d d 3 o CD r * M c3 M g s a O ft 3 a o > (3 O 3 «8Q 2 3 K w W W ft 3 o D Q © 3 > c. O 3 2 3 tg ^ W K a 3 O Q Q © i i 1 6 SJ so 3 O (4 ft 3 ft ft o X 0> > 1 ■ O 3 u 3 K X X K u a 3 o Q Q 6 CM 6 6 6 3 u 230 204.3 103.2 106.6 105.2 99.1 149.4 157.2 180.2 189.7 230 231 205.2 103.7 107.1 105.7 99.6 150.0 157.9 181.0 190.5 231 232 206.1 104.1 107.6 106.2 100.1 150.7 158.6 181.8 191.3 232 233 207.0 104.6 108.1 106.7 100.6 151.4 159.3 182.6 192.2 233 234 207.9 105.1 108.6 107.2 101.1 152.0 160.0 183.4 193.0 234 235 208.7 105.6 109.1 107.7 101.6 152.7 160.7 184.2 193.8 235 236 209.6 106.0 109.5 108.2 102.1 153.4 161.4 184.9 194.7 236 237 210.5 106.5 110.0 108.7 102.6 154.0 162.1 185.7 195.5 237 238 211.4 107.0 110.5 109.2 103.1 154.7 162.8 186.5 196.3 238 239 212.3 107.5 111.0 109.6 103.5 155.4 163.5 187.3 197.2 239 240 213.2 108.0 111.5 110.1 104.0 156.1 164.3 188.1 198.0 240 241 214.1 108.4 112.0 110.6 104.5 156.7 165.0 188.9 198.8 241 242 215.0 108.9 112.5 111.1 105.0 157.4 165.7 189.7 199.7 242 243 215.8 109.4 113.0 111.6 105.5 158.1 166.4 190.5 200.5 243 244 216.7 109.9 113.5 112.1 106.0 158.7 167.1 191.3 201.3 244 245 217.6 110.4 114.0 112.6 106.5 159.4 167.8 192.1 202.2 245 246 218.5 110.8 114.5 113.1 107.0 160.1 168.5 192.9 203.0 246 247 219.4 111.3 115.0 113.6 107.5 160.7 169.2 193.6 203.8 247 248 220.3 111.8 115.4 114.1 108.0 161.4 169.9 194.4 204.7 248 249 221.2 112.3 115.9 114.6 108.5 162.1 170.6 195.2 205.5 249 250 222.1 112.8 116.4 115.1 109.0 162.7 171.3 196.0 206.3 250 251 223.0 113.2 116.9 115.6 109.5 163.4 172.0 196.8 207.2 251 252 223.8 113.7 117.4 116.1 110.0 164.1 172.7 197.6 208.0 252 253 224.7 114.2 117.9 116.6 110.5 164.7 173.4 195.4 208.8 253 254 225.6 114.7 118.4 117.1 111.0 165.4 174.1 199.2 209.7 254 255 226.5 115.2 118.9 117.6 111.5 166.1 174.8 200.0 210.5 255 256 227.4 115.7 119.4 118.1 112.0 166.8 175.5 200.8 211.3 256 257 228.3 116.1 119.9 118.6 112.5 167.4 176.2 201.6 212.2 257 258 229.2 116.6 120.4 119.1 113.0 168.1 176.9 202.3 213.0 258 259 230.1 117.1 120.9 119.6 113.5 168.8 177.6 203.1 213.8 259 260 231 . 117.6 121.4 120.1 114.0 169.4 178.3 203.9 214.7 260 261 231.8 118.1 121.9 120.6 114.5 170.1 179.0 204.7 215.5 261 262 232 . 7 118.6 122.4 121.1 115.0 170.8 179.8 205.5 216.3 262 263 233.6 119.0 122.9 121.6 115.5 171.4 180.5 206:3 217.2 263 264 234 5 119.5 123.4 122.1 116.0 172.1 181.2 207.1 218.0 264 265 235 4 120.0 123.9 122.6 116.5 172.8 181.9 207.9 218.8 265 266 236.3 120.5 124.4 123.1 117.0 173.5 182.6 208.7 219.7 266 267 237.2 121.0 124.9 123.6 117.5 174.1 183.3 209.5 220.5 267 268 238.1 121.5 125.4 124.1 118.0 174.8 184.0 210.3 221.3 268 269 238.9 122.0 125.9 124.6 118.5 175.5 184.7 211.0 222.1 269 270 239.8 122.5 126.4 125.1 119.0 175.1 185.4 211.8 223.0 270 271 240.7 122.9 126.9 125.6 119.5 176.8 186.1 212.6 223.8 271 272 241.6 123.4 127.4 126.2 120.0 177.5 186.8 213.4 224.6 272 273 242.5 123.9 127.9 126.7 120.6 178.1 187.5 214.2 225.5 273 274 243.4 124.4 128.4 127.2 121.1 178.8 188.2 215.0 226.3 274 275 244.3 124.9 128.9 127.7 121.6 179.5 188.9 215.8 227.1 275 276 245.2 125.4 129.4 128.2 122.1 180.2 189.6 216.6 228.0 276 277 246.1 125.9 129.9 128.7 122.6 180 8 190.3 217.4 228.8 277 278 246.9 126.4 130.4 129.2 123.1 181.5 191.0 218.2 229.6 278 279 247.8 126.9 130.9 129.7 123.6 182.2 191.7 218.9 230.5 279 280 248.7 127.3 131.4 130.2 124.1 182.8 192.4 219.7 231.3 280 281 249.6 127.8 131.9 130.7 124.6 183.5 193.1 220.5 232.1 281 282 250.5 128.3 132.4 131.2 125.1 184.2 193.9 221.3 233.0 282 283 251 . 4 128.8 132.9 131.7 125.6 184.8 194.6 222.1 233.8 283 284 252.3 129.3 133.4 132.2 126.1 185.5 195.3 222.9 234.6 284 GENERAL METHODS 15 MUNSON AND WALKER'S TABLE— Continued [Expressed in milligrams.] ? IT Invert Sugar and Sucrose Lactose Maltose 6 3 o 3 3 o o 12 9 u "8 o "8 O O 12 o "3 O 3 M 3 H o H ffi w O m § EC O S 8 8 M | 1 6 o 3 O u ft 3 ft ft o 0* > a O 3 2 3 ffi H i W ft 3 o O p O* § M S3 S O P. 3 & o <0 > O 3 2 3 w w B a 1 o U Q *-* © a H O w W o ! 1 U V a o s X 0J a s S °s 2 3 O o 5 S ' 9. 3 O Ph ft 3 O O A o" u > £5 6% 2 3 0«2 S 1 1 1 o u ft 3 o O Q © CH Ol /H 2 HC N^ This alkaloid is usually seen as an oily syrup, as it is very hygroscopic, but it may be obtained in the anhydrous condition, and, when quite pure, is crystalline. It is readily soluble in water, solutions of caustic alkalies, alcohol, chloroform, and benzol, and less so in ether. The solutions of the alkaloid and its salts are dextro-rotatory, (a) d = +100.5°. It is con- verted into isopilocarpin by heating the hydrochloride for half an hour at 204-205°, or by distilling the free base in vacuo. An acid solution gives precipitates with Mayer's reagent and iodine, but none with potassium ferrocyanide nor tannic acid. Picric acid gives a precipitate in concentrated _ ALKALOIDS DERIVED FROM PYRIDIN 93 solution acidulated with hydrochloric acid. It may be shaken out from weak ammoniacal solution but not from a solution of caustic alkali. Bromine acts on it at high temperatures giving bromcarpinic acid, CioHi5N 2 4 Br, melting 209°. Pilocarpin gives few color reactions on which any reliance can be placed, and none with the commonly used reagents. Helen's reaction gives good results and may be applied to a solution of the hydrochloride. From .01 to .02 gram of the salt is dissolved in a little water, 1-2 mils of an acid solution of hydrogen peroxide is added, followed by 2 mils of ben- zol and a few drops of a 0.3 per cent solution of potassium bichromate. On shaking, the benzol layer will become purple to blue in the presence of pilocarpin. Pyridin and quinolin both give a violet coloration under the same conditions, but the color soon fades; apomorphin gives a violet changing to green on separating the benzol and addition of dilute stan- nous chloride; antipyrin gives a blue color, distinguishable from that of pilocarpin by shaking the benzol layer with water containing a trace of hydrochloric or sulphuric acid, and treating this acid layer as before with peroxide, bichromate, and benzol, when the color will be regenerated, which is not the case with pilocarpin. Apomorphin is usually indicated long before it is finally separated from a mixture by the green color im- parted to the solution, and the reddish- violet color imparted to the solvents, on shaking out from alkaline solutions. Pilocarpin or its hydrochloride reduces calomel when intimately mixed with it, the reaction being similar to that produced by cocain. Pilocarpin forms certain well-defined salts, the nitrate melting 178°, the hydrochloride melting 204-205°, the hydrobromide melting 185°, the picrate melting 158-160°, the aurochloride melting 100°. Pilocarpidin This body occurs in very deliquescent crystals, strongly alkaline, soluble in alcohol, chloroform, and water and slightly so in ether and benzol. It is optically active. It possesses acid properties and unites with alkalies to form salts which are readily decomposed by carbon dioxide. Isopilocarpin This alkaloid bears a close resemblance to pilocarpin and its stereo- isomer. It has {a) D = +42.8°. It forms the same well-defined salts as pilocarpin, the nitrate melting 159°, the hydrochloride melting 127°, and hydrobromide melting 147°. Quantitative Determination. — As pilocarpin will seldom be found mixed with any other alkaloid, its determination may be accomplished without difficulty. In the case of tablets of pilocarpin hydrochlorate or nitrate, about twenty-five should be transferred to a separator, disinte- 94 .ALKALOIDAL DRUGS grated with a little water, then ammonia added and the alkaline mixture shaken out three times with chloroform. The combined chloroform extracts are then shaken out with three portions of normal hydrochloric acid, and the pure alkaloid finally removed from this latter solution with chloroform after adding excess of ammonia. Pilocarpin may be determined in hair tonics by first removing the alcohol by distillation or evaporation, adding ammonia, shaking out the alkaloid with chloroform, and purifying it as in the case of tablet deter- mination. In case the first manipulation with chloroform is difficult, owing to emulsification, Prolius mixture can be substituted to advantage, and in the event of such a solvent being used it must be removed by evaporation before proceeding with the purification. SPARTEIN C 15 H 26 N 2 H 2 •CH 2 • CH \~ C ~/CH 2 • CH 2 \ HC— CH 2 • CH 2 — N N— CH 2 • CH 2 — CH \CH 2 • CH 2 / \CH 2 • CH 2 / This alkaloid occurs in the broom plant, Cytisus scoparius (Fabaceae), the tops of which are used medicinally. It is also reported by Willstatter and Marx as occurring in Lupinum luteus and L. niger. The alkaloid is usually applied in the form of its sulphate, it is laxative and diuretic, is employed in dropsy due to the heart, and in anasarca of chronic kidney disease, and may be expected in cardiac pills and tablets. Spartein sul- phate is sold alone in the form of tablet triturates and hypodermatic tablets, and in heart tonic mixtures in conjunction with Cactus grandi- florus, digitalin, strychnin, nitroglycerin, and strophanthin or with Stro- phanthus, caffein, and codein. Spartein has been used as an ingredient of treatments for the drug habit combined with morphin sulphate, heroin, caffein, pilocarpin, and carbolic acid. Pure spartein is a colorless, oily liquid, heavier than water, with an odor resembling anilin, and a very bitter taste. It darkens and thickens on exposure to air. When pure it boils about 320° C. under normal pres- sure. It is lsevorotatory in absolute alcohol, readily soluble in alcohol, ether, chloroform, and petroleum ether, slightly soluble in water and insoluble in benzol. It gives no characteristic color reactions with mineral acids. It is precipitated from solutions of its salts by a number of alkaloid reagents, and some of the salts obtained are crystalline with definite melting-points, the platinochloride melts 244-257° with decomposition, the aurochloride melts 175-180° with decomposition, the picrate melts 178-180°. It gives precipitates with Mayer's and Wagner's reagents, cadmium iodide, ALKALOIDS DERIVED FROM PYRIDIN 95 sodium phosphomolybdate, silico-tungstic acid, potassium iodide,, bromine water,, etc. Spartein is volatile with steam. A piece of moistened red litmus paper held over a vessel containing the free alkaloid is gradually turned blue. An ethereal solution of iodine added to a solution of spartein in ether causes the precipitation of a black periodide. This substance may be dissolved in boiling alcohol and on cooling separates out in the form of green needles. An orange-red coloration is produced when spartein is treated with a drop of ammonium sulphydrate. An ethereal solution of spartein to which about 20 mg. of dry sulphur has been added, yields an abundant bright red precipitate on passing hydrogen sulphide. Coniin, when treated in the same way, gives an orange turbidity. Spartein is readily oxidized by calcium hypochlorite, hydrogen per- oxide, silver oxide, etc., and yields a series of oxysparteins. The ordinary form in which spartein occurs in the market is the sul- phate, CioH26N2-H2S04+5H20, which is a slightly hygroscopic salt, readily soluble in water and alcohol. When spartein is added to ferric chloride and potassium thiocyanate which have been spotted out on a porcelain plate and dried, a violet to reddish shade is obtained. When spartein hydriodide is heated with methyliodide two isomeric iodomethylates are formed. The hydriodides of these are decomposed by heat into methyliodide and spartein hydriodide, the latter being the same substance in both cases. Iso-spartein hydriodide, when treated with sodium carbonate, gives the free base which is an oil boiling at 177- 179° C. at IQto m., insoluble in water, but soluble in the ordinary organic solvents, rotation (a) D = 25.01, specific gravity 1.02793 at 17° nd= 1.53319 at 17°. It resembles spartein in all its reactions. Valeur 1 reports the isolation of a volatile alkaloid from the mother liquors from the crystallization of commercial spartein sulphate. This base, to which the name genistein, Ci6H 2 sX2, is given, melts 60.5° and boils at 177-178° at 22 mm. It does not reduce permanganate. It forms a picrate melting 215° and a platinochloride containing water which is lost at 110°, the anhydrous substance decomposing at 225° without melting. In the systematic scheme of alkaloidal analysis, spartein will appear in the petroleum ether shake-out from ammoniacal solutions. If it is suspected by preliminary tests, it may be readily separated from other alkaloids with which it may occur by a steam distillation and its identity established beyond question by appropriate tests, the most character- istic of which have been described above. To determine spartein, when it occurs as the sulphate alone in tablets, the sample should be disintegrated with water in a separator, treated ij. Pharm. Chim., 1913, 8, 573. 96 ALKALOIDAL DRUGS with excess of ammonia and shaken out three times with ether; the ether- eal solutions are combined and shaken out with dilute hydrochloric acid, and the acid solution treated with excess of ammonia and shaken with ether; the ether, which now contains pure spartein, should be filtered into a tared flask and subjected to dry hydrogen chlorid gas in slight excess, the ether carefully evaporated and the residue warmed and sub- jected to a gentle blast to remove the excess of acid and then dried in a vacuum desiccator. In the case of mixtures the alkaloids should first be separated in a crude way by shaking out an ammoniacal solution with ether and chloro- form, and then extracting this ether solution with dilute sulphuric acid; the acid solution is transferred to a distilling flask fitted up for steam distillation, the bases liberated with fixed alkali and the spartein distilled over into dilute acid, from which it may be separated as previously described. Strychnin may be determined in the solution remaining in the distilling flask by shaking out with chloroform. Codein, if present, would probably be partly decomposed. Spartein can also be determined as the silicotungstate. The alkaloid, separated from the rest of the mixture in which it occurs by suitable means similar to that above described, is finally brought into solution in very dilute hydrochloric acid and precipitated by a 10 per cent solu- tion of silicotungstic acid or its potassium salt. The precipitate may be filtered onto a Gooch and dried at 100°. It has the composition SiC>2, 12W0 3 , 2H 2 ; 2C15H26N2+7H2O. LOBELIN Lobelin is an alkaloid of Lobelia inflata (Lobeliacese) , Indian tobacco, the leaves and tops of which furnish the drug which is used extensively in asthma remedies. There are other species of Lobelia which are used medicinally, L. cardinilis, cardinal flavor, and L. syphilitica. The con- stituents of these subsidiary drugs have not been determined, the first named has been used as an anthelmintic and the latter as an antisyphilitic. Extract of lobelia and lobelin sulphate are employed medicinally. The extract will be found with Sanguinaria and skunk cabbage, in fluid extract lobelia compound, and in tablets and elixirs recommended for asthma and croup where it is mixed with bromides and iodides, nitroglycerin and Euphorbia pilulifera. The crude alkaloid has an odor suggestive of honey and tobacco, but is odorless and colorless when pure. It is a volatile, amorphous base, permanent in the air, slightly soluble in water, but dissolving in all the ordinary organic solvents including petroleum ether. As ordinarily ex- tracted from mixtures or the drug it will be obtained as a yellow syrup. ALKALOIDS DERIVED FROM PYRIDIN 97 It is precipitated by the usual alkaloidai reagents and gives a very insoluble compound with tannic acid. Sulphuric acid gives a red color and nitric acid yellow. When warmed with 10 per cent alkali containing 4 per cent permanganate, benzoic acid is formed, which may be separated by filtering, acidifying, and shaking out with ether. Lobelin sulphate is hygroscopic. In the usual scheme of medicinal analysis lobelin will appear in the fraction obtained on shaking out the alkaline solution with petroleum ether. When the solvent is evaporated the alkaloid will be left as a yellowish oily or syrupy liquid having the characteristic odor above mentioned. Residues of lobelin should not be heated after the solvent is evaporated on account of the volatility of the base. This property may be used to advantage in separating lobelin from sanguinarin in case it is desired to test for both in the same residue. They both give a red color with sulphuric acid, and while lobelin would probably be indicated by its odor, the presence of sanguinarin could only be ascertained with certainty by removing the lobelin by distillation. It may be observed, however, that while lobelin may be to a considerable extent removed from an alkaline solution by petroleum ether, very little sanguinarin will come out at this point. The analyst should look carefully for lobelin in asthma, catarrh, and hay fever cures, especially in those which are advertised extensively to the laity. It is probably employed to a larger extent than is credited owing to the fact that it would be easily lost or overlooked. CYTISIN Cytisin occurs in a number of minor drugs, among which may be mentioned Baptisia tinctoria (Fabacese), wild indigo, used principally as an antiseptic in washes and ointments; Cytisus laburnum, false ebony, which has been recommended in whooping cough, vomiting, bronchitis, and asthma; Euchresta horsfieldii, a Javanese pea used as a contra-poison by the natives; Genesta tinctoria, used as a cathartic and sometimes as a diuretic in dropsy; and in several species of Sophora and Ulex. It is identical with several alkaloids to which formerly different names were applied, ulexin, baptitoxin, and sophorin. B. tinctoria is probably the only drug which the analyst will encounter in ordinary practice. With the oils of eucalyptus and gaultheria, boric acid, menthol, and thymol it is used in the composition of antiseptic washes of the type resembling " listerine." Cytisin, C11H14N2O, is a diacid base readily soluble in water, alcohol, and chloroform, but only sparingly in ether or petroleum ether. It crys- tallizes from alcohol in prisms which melt 152-153° or at 156° when 98 ALKALOIDAL DRUGS thoroughly dried; it is laevorotatory and strongly alkaline, easily displac- ing ammonia from its salts. According to Mullikin it may be removed from acid solution by means of chloroform. It may be sublimed unchanged in a vacuum. Its salts are crystalline and in some cases two types have been prepared. The aurochloride melts 212-213° and is veiy insoluble. Two platinochlorides are known and are much more soluble than the gold salt. The compound with mercuric chloride is character- istic. It gives precipitates with the usual alkaloidal reagents. Cytisin gives a red color with ferric chloride which is very character- istic and sensitive even with minute amounts. The red color is destroyed by hydrogen peroxide, and on warming the liquid a blue color is produced. Sulphuric acid added to cytisin gives no color reaction, but on adding thymol and warming a yellow color appears, soon becoming red. Bichro- mate added to a sulphuric acid solution produces a yellow to brown color. Nitrobenzol containing a trace of nitrothiophen colors the alkaloid violet red. In the general scheme of alkaloidal analysis cytisin will be found in the fraction obtained by shaking out the alkaline solution with ether, though probably the greater portion will be subsequently removed on shaking out with chloroform. DELPHINIUM BASES Extracts of the seeds of Delphinium staphisagria (Ranunculacese), stavescare from Southern Europe, and of D. consolida, the common field larkspur of the United States, are employed to a limited extent as medici- nal agents. Another species, D. urceolatum, growing in the United States, is sometimes substituted for D. consolida. Stavescare is a power- ful emetic, narcotic, carthartic, and vermifuge as well as a parasiticide. It is prescribed in various disorders of the urinary tract, including tem- porary enlargement or irritation of the prostate, and may therefore be suspected in any remedy recommended for such ailments. It is used externally for eczema and for destroying lice and itch mite. Larkspur is used principally as a parasiticide for destroying crab- lice and vermin infecting the scalp. The bases of D. staphisagria which have been definitely established include delphinin, delphisin, and probably delphinoidin. D. consolida may contain some or all of these bases. Keller 1 obtained a crystalline alkaloid from the latter drug, which w T as not identical physiologically with delphinin. He also determined that the commercial delphinin is a mixture. The alkaloids may be extracted from an alkaline solution by ether, 1 Arch. Pharm., 248, 463. ALKALOIDS DERIVED FROM PYRIDIN 99 and on concentrating and allowing to stand the delphinin crystallizes first in rhombic crystals melting 191-198°; on further evaporation delphisin separates, and then dilphinoidin may be thrown out by adding petroleum ether. The pure bases do not give characteristic color tests. Reactions have been reported which were obtained with impure residues: thus sulphuric acid containing malic acid produces an orange color, changing gradually to red and finally dirty blue; sulphuric acid and bromine water a violet color; and sulphuric acid and sugar a brownish yellow changing to green on dilution with water. BASE FROM DUBOISIA HOPWOODH Duboisia hopwoodii (Solanacese), growing in central Australia, is another of those plants like coca and kola which furnishes a drug having stimulating properties enabling its devotees to perform much labor and go long journeys with but little food. The drug is a fine powder composed of the leaves and twigs gathered while the flower is in bloom and put up in various forms of circular mats about 6 in. in diameter. The drug has not been exported medicinally to any extent, but attention is called to it owing to its local use, which may lead to its adoption by the pharmaceu- tical profession after the manner in which coca and kola were first exploited. The drug contains a volatile alkaloid which has been called piturin, after the local name of the drug Pituri. Investigation by different workers has been conflicting, some claiming it to be identical with nicotin, others denying this similarity. Senft states that it differs from nicotin in its reactions with platinic, gold, and meruric chlorides, and with iodine. Its aqueous solution does not become turbid on heating, which distin- guishes it from coniin, CHAPTER V ALKALOIDS DERIVED FROM PYRROLIDIN THE SOLANUM ALKALOIDS Atropin, C17H23NO3 Hyoscyamin, C17H23NO3 Scopolamin, C17H21NO4. In addition to the above three it has been recorded that the drugs bearing these alkaloids contain small amounts of atropamin, belladonin, mandragorin and pseudohyoscyamin. However, their existence is doubt- ful, the literature on the subject is discrepant and it appears from more extended research that they were mistaken for mixtures in varying pro- portions of the three alkaloids. Hyoscin, which was formerly reported as a naturally occurring constituent of henbane, has now been virtually relegated to oblivion. Daturin, now called atropin, was probably a mixture of atropin and hyoscyamin; duboisin is now classed as hyos- cyamin by some and as scopolamin by others. This group includes also the artificially prepared homatropin, C10H21NO3, having the composition of a lower homologue of atropin as well as other synthetic derivatives of tropein, which are used more or less in medicine. The following plants of the Solanacese have been found to contain these alkaloids; Atropa belladonna, Deadly Nightshade; Hyoscyamus niger, Henbane; H. albus, H. muticus; Datura stramonium, Thorn- apple or Jamestown Weed, and other species of Datura; Duboisia myopo- roides, Corkwood Elm; Scopolia atropoides or carniolica; S. japonica, Japanese Belladonna; Mandragora officinarum, European Mandrake, Anisodus luridus, and according to some authors in Lactuca sativa and virosa (Compositse) . All parts of the plants contain the alkaloids. The relative proportions of the alkaloids have never been satisfactorily deter- mined owing to the ease with which hyoscyamin is converted to atropin, but the consensus of jopinion seems to be that atropin predominates in belladonna, though Rusby states that over one-half the total alkaloid in the commercial root is hyoscyamin according to Gilpin and Langdon, while hyoscyamin and scopolamin are present in greater amount in hen- 100 ALKALOIDS DERIVED FROM PYRROLIDIN 101 bane. Pseudohyoscyamin was reported by Merck in Duboisia myopo- roides, but has never been observed in any other species. The young roots of belladonna are reported to contain scarcely any atropin, only hyoscyamin, while the ripe fruit on analysis contains only atropin. The alkaloidal content varies with the period of their growth. Gunther has shown that the fresh plants contain the alkaloids in the following proportions expressed in parts per 1000. Atropa belladonna, leaves 2.0; stems 0.4: unripe fruit 1.9; ripe fruit 2.1; seeds 3.3; root 0.6. Datura stramonium, leaves 0.7; stems 0.2; seeds 2.5; root 0.2. The drugs used medicinally when ready for market contain the alka- loids in the following percentages: Atropa belladonna 0.2 to 1.0 per cent, the average being 0.55 to 0.60. The Pharmacopoeia requiring the leaves test not less than 0.30 per cent and the root 0.45 per cent. Hyoscyamus .00 to 0.15 per cent, the standard requirement being .065 per cent. Scopola somewhat greater than the amount present in belladonna root, the old standard being 0.5 per cent, but the drug is no longer official. Stramonium 0.2 to 0.4 per cent, the Pharmacopoeia requiring not less than 0.25 per cent. The crude belladonna leaves have been found mixed with those of Scopola and sometimes with a species of Phytolacca; Belladonna root has been largely adulterated with Phytolacca root and the literature records the use of Medicago root and Scopola; Hyoscyamus leaves have been adulterated with Stramonium; and Stramonium has been found adulterated with other species of Datura and also with a spurious Stra- monium called " French cultivated." Hyoscyamus muticus is often offered for import as true H. niger. The substitution of one drug for another or the use of an adulterant may be detected microscopically in powdered products ; in liquid prepar- ations the analyst's difficulties become greater, especially where one vari- ety of the Solanaceae has been substituted for another, though the use of products containing Phytolacca should be more readily detected owing to the entirely different nature of the ingredients in the latter. Extract of belladonna will be found usually in combination with other drugs, and is employed as an anodyne, a suppressant of secretions, for whooping cough, croup, chronic constipation, incontinence of urine, nar- cotic poisoning, etc. It is an antigalactogogue, and is a component of many different kinds of plasters. The alkaloid has a wide use as a mydri- atic. The drug or its alkaloids are chiefly administered in the form of pills and tablets and a large number of different formulge have been evolved. Scopola is used as an anodyne. Hyoscyamus is a deliriant narcotic, 102 ALKALOIDAL DRUGS anodyne, antispasmodic, and hypnotic, and is employed chiefly to relieve pain and quite nervous excitement. It is used in asthma, whooping cough, functional palpitation of the heart, chorea, hypochondriasis, mania, etc., and also as a sedative in place of opium. Stramonium is a powerful narcotic, antispasmodic, and anodyne, and is used similarly to belladonna. It is employed in the powered form as a remedy for asthma. The extract of Duboisia is used for the same purposes as belladonna, but is claimed to be less of a cerebral excitant and more calmative and hypnotic. Mandragora is stated by Rusby to be the Mandrake of the Bible; it has properties similar to the other drugs of this family, but will seldom if ever be met with in the course of analytical work. From the above resume of the uses of the drugs and alkaloids under consideration an idea may be formed as to the different remedies in which they might be expected Some of the more important combinations of belladonna and atropin include the following: Pills. Belladonna and aloes or aloin with Nux Vomica or strychnin to which will often be added Capsicum, ginger, Cascara, ipecac, colocynth, and calomel, one or more in different combinations. In some instances Podophyllum will take the place of the Nux Vomica and again the aloes will be omitted. Belladonna, podophyllum and Physostigma are used together; and belladonna is combined with phosphorus. As a compo- nent of neuralgic and idiopathic remedies it occurs with Hyoscyamus, Ignatia, Opium, Conium, Stramonium, Aconite and Cannabis sativa; with salicin, zinc oxide, pepsin and Hydrastis it is used for night sweats. Pills of morphin and atropin are used, and atropin has also been combined with quinin, arsenic, and gentian. Tablet triturates will be found containing many of the above men- tioned mixtures of aloin, belladonna, strychnin, Cascara, Podophyllum, ipecac, etc. Bronchitis mixtures are found containing belladonna, acon- ite, Bryonia, sulphurated antimony and potassium bichromate, or bella- donna, opium, ipecac and quinin. Atropin, morphin, camphor, and quinin are used for coryza. An infant's cough formula contains ammo- nium chloride, ipecac, opium, Glycyrrhiza, and belladonna. A standard formula for follicular tonsillitis contains belladonna, aconite, Bryonia, mercuric iodide, morphin, sodium salicylate, and methyl salicylate. It is used with nitroglycerin, Strophanthus, and Digitalis in heart tonics; it is combined with picrotoxin alone; rhinitis formulas contain bella- donna, camphor, and quinin; throat tablets contain benzoic acid, cam- phorated opium, Glycyrrhiza and belladonna; and a formula is reported for sciatica containing belladonna, aconite, Colchicum and Cimicifuga. ALKALOIDS DERIVED FROM PYRROLIDIN 103 In the formulas of compressed, sugar-coated and chocolate-coated tab- lets belladonna or atropin take part in a legion of mixtures, many are repetitions of those above given, but to these may be added the following: with potassium iodide, potassium arsenite, Lobelia, and opium in asth- matic compounds; with sanguinarin nitrate, morphin, antimony, and potassium tartrate, aconite, ipecac, and tar in a cough mixture; with boric acid, benzoic acid, potassium bicarbonate, buchu, Triticum, corn silk, Hydrangea in mixtures for cystitis; with gold and sodium chloride, strych- nin, nitroglycerin, Digitalis, and Capsicum for dipsomania; with lupulin, Scutellaria, ergotin and zinc bromide; with saw palmetto, cantharides and cornsilk; with terpin hydrate, wild cherry, guaiac, and camphorated opium; with antipyrin ; zinc oxide, and Castanea for whooping cough. Ophthalmic tablets of atropin sulphate and of homatropin hydro- bromate are used considerably.. Hypodermatic tablets contain atropin sulphate alone and combined with morphin sulphate, and there is a local anesthetic formula containing atropin sulphate, morphin sulphate, and cocain hydrochlorate. Elixirs are sold to a limited extent containing aloin, belladonna, strych- nin and Podophyllum; and a tonic compound sold in capsule form con- sists of atropin, beechwood creosote, strychnin, arsenous acid, and cod liver oil. Belladonna ointment usually has a base of benzoinated lard. Bella- donna plasters contain lead oleate, petrolatum, rubber, and sometimes soap, colophony and Burgundy pitch in the base. Hyoscyamus, in the form of the drug extract, enters into a great vari- ety of different combinations, many of which resemble to a greater or less extent those in which belladonna functionates and, consequently they will not be repeated here. Among the pills and tablets attention will be directed to those which have been found to differ from the formulas given above under belladonna. Hyoscyamus with camphor, Capsicum and morphin in anodyne products; with Podophyllum, colocynth, Cascara, Juglans, Nux Vomica, gentian and Apocynum, also with jalap, leptandra, aloin, gamboge and Capsicum in laxative remedies; in the compound vegetable cathartic of the National Formulary. With camphor, valerian and Opium; with irisin and strychnin; with musk root, valerian, and Cannabis sativa in sedative mixtures; with ammonium chloride, Gly- cyrrhiza, Tolu, cubeb, senega, and ipecac in bronchial remedies; with calomel, rhubarb, and colocynth; with morphin hydrochloride, Cannabis sativa, nitroglycerin, Capsicum, and peppermint in chlorodyne; with ferrous lactate, cinchonin sulphate, arsenous acid, and strychnin; with sodium bromide, acetanilid, and digitalin in hypnotic compounds; with acetanilid, camphor monobromated, sodium salicylate, and Gelsemium for migraine; with sodium bromide, caffein, acetanilid, and morphin for 104 ALKALOIDAL DRUGS neuralgic headache; and with opium, Hamamelis, tannic acid, thymol helonias, salicylic acid, boric acid, alum, and eucalyptol for topical use in leucorrhea. Scopolamin, hydrobramate (Hyosin.) hyoscyamin, and Hyoscyamus extract individually occur in tablet triturates, and the alkaloidal salts occur in hypodermatic tablets. The liquid products are not numerous and are usually elixirs; thus we have a formula embracing chloral, potassium bromide, Cannabis sativa, and Hyoscyamus, and another with the same ingredients includ- ing morphin; again a product of the nerve tonic type composed of skull- cap, hops, Hyoscyamus, valerian, ammonium bromide, and coca. Scopola resembles belladonna very closely in medicinal and physio- logical action but is not used to the same extent. It has been largely employed in the manufacture of plasters and is also the source of most of the commercial scopolamin (hyoscin) salts. Stramonium occurs in the pill formula mentioned under belladonna which is used for neuralgia idiopathic, but its greatest field is in asthma powders, pastilles, and cigarettes. In powders it occurs with Grindelia robusta, Pilocarpus, Eucalyptus, coca, Digitalis, cubeb, cascarilla, and potassium nitrate; in pastilles with benzoin, Pilocarpus, charcoal, and potassium nitrate; and in cigarettes with cascarilla, Lobelia, and mul- lein. Treatments for the drug and liquor habits often contam scopolamin, and with this alkaloid may occur morphin sulphate heroin, cafTein, spar- tein, Pilocarpus, and carbolic acid, Atropin. Tropyl-tropin. Inactive Atropin. Daturin. H H 2 C C CH 2 CH 2 OH I \ I N • CH 3 CH • O • CO CH— C 6 H 5 I / H2C C CH2 H Pure atropin forms tufts or groups of colorless or white lustrous needles or acicular prisms, crystallizing in this way from alcohol or chloroform. In commerce it often occurs as a crystalline or nearly amorphous yellowish powder, and the commercial article usually contains hyoscyamin, from which it may be freed by treatment with dilute alcoholic alkali at a tem- perature of 110° for five or six hours, until there is no further change in its optical activity. Pure atropin is without action on polarized light. Hyoscyamin is its stereoisomer, being the laevo modification, while atropin is the racemic form. The separation of the latter has not as yet been effected, although the constituents have apparently been synthesized. ALKALOIDS DERIVED FROM PYRROLIDIN 105 It is a strong poison and is used largely in medicine on account of its mydriatic and other properties. Its property of dilating the pupil of the eye is used to confirm its presence. The pure alkaloid melts 115-116° C, while the commercial substance containing more or less hyoscyamin, melts from 104 to 114°. It is sublimable, almost unchanged; and gradually loses weight when heated to 100° C. It is somewhat volatile with steam. It is readily soluble in alcohol, chloroform, carbon tetrachloride, and toluol, less so in ether and only slightly soluble in petroleum ether and carbon bisulphide. The proportions given in the literature for its solu- bility vary over wide limits. It is not removed by immiscible solvents from solutions acidulated with mineral acids, but from solutions made acid by tartaric acid it is stated that ether and chloroform will remove it. Its aqueous solution is alkaline to litmus and reddens phenolphthalein, the latter property being almost exclusively characteristic of atropin and its isomers among the other alkaloids. Atropin is precipitated by Mayer's reagent, iodin in potassium iodide, potassium-bismuthous iodide, potassium-cadmium iodide, phospho-molyb- dic and phosphotungstic acids, tannic acid; alcoholic picric acid yields a precipitate having a characteristic form, valuable in microscopic detec- tion, and a saturated solution of bromin in hydrobromic acid or alcohol produces a precipitate in dilute solutions, amorphous at first, but soon becoming crystalline and highly characteristic. No precipitates are given with potassium iodide, sulphocyanide, ferro, and ferri-cyanide, nor chro- mate. Gold chloride produces a very characteristic precipitate with atropin, in fact the gold chloride compound furnishes the best test for distinguish- ing between this alkaloid and the other solanum bases. It is thrown down from dilute solutions as an amorphous or oily precipitate which gradually becomes crystalline, and has a well-defined form under the microscope. It melts under hot water and is deposited from its solution in boiling water acidulated with Irydrochloric acid in minute crystals which are luster- less after drying at 80° and melt at 135-138°. Hyoscyamin aurochlo- ride retains its luster when dry and melts 160-162°; scopolamin auro- chloride melts 198-199°, and homatropin aurochloride 142-145°. Atropin picrate melting 174.5-175° C. is prepared by adding a few mils of a saturated solution of picric acid to a fairly concentrated solu- tion of the alkaloid in dilute hydrochloric acid. After washing with water, the precipitate should be recrystallized from dilute acetone. Bromine water in aqueous hydrobromic acid produces characteristic crystals even in very dilute solution. These crystals when viewed under the microscope furnish an excellent test of identity. 106 ALKALOIDAL DRUGS With platinic chloride atropin gives a powdery, resinous precipitate which balls together and is very soluble in hydrochloric acid. Hence from solutions acidulated with hydrochloric acid it is not thrown down by platinic chloride, a reaction which distinguishes atropin from the great majority of alkaloids and which may be used to a certain extent for sepa- rating mixtures. On evaporating a dilute solution of the platinum salt it separates in monochinic crystals which melt with decomposition at 207-208°. Atropin sulphate is the form in which it usually appears commercially, though this product is rarely chemically pure, containing a trace of hyos- cyamin. The melting-point of this body is given variously from 180 to 191° C. Beilstein states that the commercial article containing hyoscyamin melts at 188-191° and the pure salt free of hyoscyamin at 181-183°. Atropin and allied bases respond to a number of interesting color and odor tests. Vitali's color reaction is probably the most sensitive and furnishes a very good indication of the presence of these alkaloids. It is easy of application, the alkaloidal residue being first evaporated with concentrated nitric acid, and when dry and cool the product treated with a few drops of strong alcoholic potash, when in the presence of solanum bases a beautiful purple color appears going through the entire liquid and gradually disappearing through a cherry red. The purple color may be again produced by evaporating with nitric acid and treating with alco- holic potash. While this reaction is of great value as an indication of the presence of atropin, it cannot be considered as conclusive proof, as other alkaloids and alkaloidal residues obtained from medicinal products will give the same or very similar test, so similar in fact that when working with small amounts, the distinguishing features are not apparent. Thus strychnin when similarly treated gives a purple color which is permanent, and gradually becomes brownish; yohimbin and alkaloidal residues from yohimbe bark give a purple color, the color being quite fleeting and most prominent on the edges and in thin layers and soon changing to brown; alkaloidal residues obtained from coca leaf will in some instances give a purple color, but pure cocain will not. It is claimed that veratrin will give the same test as atropin, but the writer has never been able to con- firm the statement; commercial veratrin gives a fleeting pink color when nitric acid is added, but no purple color developed on subsequently add- ing alcoholic potash to the evaporated residue ; alkaloidal residues obtained from Veratrum viride acted in the same way and in both cases there was noted a strong odor of old beef. Homatropin does not respond to Vitali's test. Gerrard has described a reaction with mercuric chloride which Allen epitomizes as follows: 0.1 grain of the free alkaloid (extracted from a ALKALOIDS DERIVED FROM PYRROLIDIN 107 salt by ammonia and chloroform) is placed on a watch glass or in a test tube and 20 drops of a 2 per cent solution of mercuric chloride in 50 per cent alcohol gradually added. A red coloration is yielded at once with atropin. Hyoscyamin at first becomes yellow, then darkens a little, and finally, on heating, a well-marked red precipitate is formed. If a large excess of hyoscyamin be used, merely a yellow precipitate is formed, while with a large excess of the reagent no precipitation occurs. Homatropin also yields a red precipitate under the conditions of the test; but hyoscin (scopolamin) gives neither a red nor a yellow coloration or precipitate, and hence is sharply distinguished from the other tropeins. Gerrard found no red or yellow precipitate to be produced by strychnin, brucin, morphin, codein, veratrin, aconitin, coniin, gelsemin, caffein, cinchonin, cinchonidin, quinin, or quinidin; though most of these bodies gave white precipitates, which, in the cases of codein and morphin, became pale yellow on heating. Cocain is also claimed to give a white precipitate (only appearing in strong solutions and soluble on warming) and scoparin a yellow precipitate. Atropin and the solanum bases yield a leaf-green to olive-green color when treated with a mixture of 1 volume of perhydrol and 10 volumes of concentrated sulphuric acid. Cocain gives an emerald-green shade. Atropin when warmed with sulphuric acid until liquid is brown and then treated with a drop or two of water gives off odors of rose, orange flower, and melilot, and the addition of potassium bichromate will change this to the odor of bitter almonds. Atropin evolves ammonia when heated with caustic alkalies. On heating with chromic-acid mixture benzoic acid is formed. The physiological test is very delicate and may be performed best on a cat's eye with a dilute neutral aqueous solution of the alkaloid or of the alkaloidal residue to be tested. No alcohol nor free acids should be present, and excess of neutral salts are to be avoided, the specimen being best prepared by evaporating either a hydrochloric or acetic solu- tion until most of the acid has disappeared, then cautiously neutralizing with sodium bicarbonate, and finally filtering. Cocain also produces mydriasis, and coniin, nicotin, aconitin, and gelseminin are stated to have a more or less similar effect on the pupil. From the above description of atropin it will be seen that for forensic work it is necessary for the analyst to consider more than one reaction when reporting an alkaloid suspected of being atropin. If sufficient quantity is obtainable the melting-point of a positively pure residue furnishes excellent proof when corroborated by the melting-points of the aurochloride and picrate, the microscopic appearance of these salts and the physiological test. The presence of cocain would be indicated by the marked odor of ethyl benzoate when the Vitali reaction was performed. ;108 ALKALOIDAL DRUGS Both dextro- and laevoatropin have been prepared; they have a melt- ing-point of 110-111° and the aurochlorides melt 146-147°. HYOSCYAMIN This alkaloid forms lustrous needles melting 108.5° C. It behaves similarly to atropin both chemically and physiologically. The optical activity, melting-point of the aurochloride and characteristic form of the picrate under the microscope serve to distinguish it from the other sola- num alkaloids. In alcoholic solutions its rotation is [a]*— 20.3° or —21°. The aurochloride does not melt in boiling water, the scales are lustrous and have a melting-point of 159-162° when pure at 165°. The picrate melts 161-164°. The platinum salt does not separate from dilute acid solution, but on evaporation of an aqueous solution it may be obtained in orange prisms melting with decomposition at 206° C. Hyoscyamin may be converted to atropin by heating for several hours at 110° or by standing for several hours in alcohol and sodium hydrate. Dehydrating agents convert it to atropamin and belladonin. On hydrolysis with barium hydrate or hydrochloric acid it gives tropin and tropic acid. On saponifying hyoscyamin with hot water Merck obtained tropin and active laevorotatory tropic acid. The laevo-tropic acid is the direct saponi- fication product of hyoscyamin; if the saponification is conducted in an acid or alkaline solution the active acid is converted into the racemic form. Hyoscyamin may thus be considered the laevo-modification of atropin. However, an experiment made in 1889 by Ladenburg and Hunt would seem to indicate that the relation existing between the two alkaloids is not so simple as we might suppose. They separated inactive tropic acid through its quinin salt into two active forms. The lsevo-acid thus pre- pared should be identical with that obtained by Merck, since in tropic acid there is only one asymmetric carbon atom. Ladenburg and Hunt on uniting this laevo-acid with inactive tropin obtained a lsevo-tropin, which although similar to hyoscyamin, was apparently not identical with it. From this one might conclude that the stereoisomeris mof the two alka- loids is not situated alone in the acid part of the molecule — the tropic acid — but also in the basic part — the tropin. According to the investigations of Gadamer, however, the tropin in both atropin and hyoscyamin is inactive, and the only difference between the two alkaloids lies in the inactivity in one case and the activity in the other of the tropic acid radicle. Recently Amenomiya states that he has obtained dextro- and laevo-hyoscyamin by the union of d- and Z-tropic acids with tropin. ALKALOIDS DERIVED FROM PYRROLIDIN 109 Z-SCOPOLAMIN Inactive scopolein ester of laevo-tropic acid Scopolamin crystallizes with one molecule of water and has a melting- point of 56-57° C. It is generally seen in the amorphous condition. Chemically and physiologically it behaves similarly to the other alka- loids of this group. It is somewhat more easily soluble in water than atropin and hyos- cyamin and dissolves readily in alcohol, ether, and chloroform. Its rotation in absolute alcohol is reported as being [a] d — 13° and —18° and in water —28°. Pictet states that the hydrobromide rotates — 25° 43'. The aurochloride melts with decomposition at 198-199° C. and Allen states that in the anhydrous condition it melts 214° C. The picrate has a melting-point 187-188°. The crystalline salts are characteristic in the microscopic form. On hydrolysis, scopolamin yields tropic acid and oscin or scopolin, and it is slowly hydrolyzed in aqueous solution. By the action of alkalies or alkaline carbonates scopolamin may oe converted into an inactive ciystalline derivative having one molecule of water and melting at 56° C, the gold chloride of which melts at 201° or 208°. In commercial scopolamin hydrobromid" Hesse found an inactive alkaloid called atroscin and which is the dihydrate of scopolamin. It melts at 38-38°. Atroscin is also found in the roots of Scopolia atropoides. It may be formed when inactive scopolamin is dried over sulphuric acid and then heated to 80° C, the residue dissolved in absolute alcohol, and a few drops of water added. The anhydrous atroscin melts at 82-83° according to Pictet. Atroscin can be converted into isoscopolamin by inoculating an atro- scin solution with a crystal of isoscopolamin and the reverse transfor- mation has been effected. Further atroscin may be changed to isoscopol- amin if the hydrobromide of the former is prepared, the base again freed from this and crystallized from an aqueous solution of definite concen- tration at 0°. Both atroscin and isoscopolamin are decomposed by alka- lies into tropic acid and scopolin. In order that the relations of these various scopolamin derivatives to one another may be more clearly represented Wolffenstein proposes the following nomenclature: The inactive anhydrous alkaloid, C17H21NO4, ^'-scopolamin. The inactive alkaloid containing one molecule of water (isoscopol- amin), i-scopolamin monohydrate. The inactive alkaloid containing two molecules of water (atroscin), z-scopolamin dihydrate. 110 ALKALOID AL DRUGS DERIVATIVES AND PRODUCTS OF HYDROLYSIS Atropamin, G7H21NO2, is formed when atropin or hyoscyamin are dehydrated with sulphuric acid or the anhydrides of phosphoric acid, acetic acid, etc. It crystallizes from ether in prisms melting at 60-62°, readily soluble in alcohol, ether, and chloroform, but only slightly soluble in water and petroleum ether. It is inactive to polarized heat and has no mydriatic effect. On being heated it undergoes a molecular rearrange- ment to form its isomer belladonin. Also when warmed with barium hydroxide or with hydrochloric acid there first occurs the same rearrange- ment, but this is then followed by saponification to atropic acid, CgNgO, and tropin. This reaction lus been reversed. On hydrolyzing the solanum bas:s we obtain the following: Atropin and hyoscyamin yield tropic acid, CgN^oOs, and tropin, C 8 H 15 NO. Scopolamin yields tropic acid and scopolin, C8H13NO2. Allen states that the preferable method for effecting the saponification of the tropeins is to heat the alkaloid with saturated baryta water to 60 or 80° for a few hours Carbon dioxide is n xt passed through the liquid until a drop ceases to give a pink color with phenolphthalein. The liquid is then filtered and the filtrate acidulated with hydrochloric acid and twice shaken with ether. The ether is separated and on evaporation yields the acid product of hydrolysis; on treating the aqueous layer with caustic alkali in excess and agitating with ether the basic product is extracted and may be recovered by separating and evaporating the ether. When the hydrolysis is effected by an acid, especially concentrated hydrochloric acid, the tropic acid loses the elements of water and atropic acid results, and at high temperatures this is more or less changed into its polymers alpha- and beta-isatropic acid, C18H16O2. Tropic acid, C 6 H 5 CH(CH 2 OH)COOH alpha-phenyl-bet a-hy droxypropi onic acid. The acid crystallizes from hot water in needles or slender prisms and on the spontaneous evaporation of its aqueous solution in tablets which melt 117-118°. It is not volatile without decomposition. It is some- what soluble in water and dissolves more readily in alcohol and ether. It is optically inactive and without any particular physiological action. When heated with a dilute solution of potassium permanganate benzal- dehyde is given off, and on further treatment benzoic acid is produced. The formula for tropic acid contains an asymetric carbon atom and it should be possible to separate the inactive acid into two active modi- fications. This separation was effected as previously mentioned by Laden- burg and Hunt by crystallizing the quinin salts. Dextro-tropic acid melts 127-128° and hevo-tropic acid 123-126°. ALKALOIDS DERIVED FROM PYRROLIDIN 111 Atropic Acid, C 6 H 5 C = CH 2 COOH alpha-phenylacrylic acid Atropic acid is isomeric with cinnamic acid, but differs from it by its solubility in water (1-692 at 19°, Allen), by its lower melting-point 106- 107°, and in not being precipitated by manganese salts from its neutral solutions. It is volatile with steam and boils with partial decomposi- tion at 267° C. It is very soluble in carbon bisulphide. Chromic acid oxidizes it to benzoic acid, and when fused with caustic potash it yields formic and phenylacetic acids. Sodium amalgam reduces it to alpha- phenyl propionic acid and bromin water converts it into brom-phenyl- propionic acid, Isatropic Acid, Ci 8 Hi60 4 This acid is polymeric with atropic acid and is always formed together with that acid and tropic acid when atropin is heated with hydrochloric acid. It is always formed when atropic acid is crystallized from hot water and especially if the solution has been boiled for some time. It exists in a number of isomeric modifications, the alpha acid melting at 237° and the beta at 206°. The gamma and delta acids are called truxillic acids, and are described under the products of hydrolysis of the coca alkaloids. Tropin H H2C C CH2 I \ N-CHs CHOH I / H 2 C C CH 2 H Tropin crystallizes from absolute ether in rhombic plates melting 61- 63° and boiling 229-233°. It is hygroscopic, readily soluble in water, alcohol, and ether. It is without action on polarized light, has no mydri- atic effect, and is much less poisonous than the alkaloids derived from it. It is a strong base, has an alkaline reaction, and forms well-crystallized salts. The platinum chloride compound forms orange-red monoclinic prisms, easily soluble in warm water, insoluble in alcohol, and melting with decom- position at 198-200°. The aurochloride forms yellow plates melting 210- 212°. The picrate is a yellow precipitate crystallizing from hot water in yellow needles, decomposing without melting at 275°. 112 ALKALOIDAL DRUGS Scopolin (Oscin), C 8 Hi 3 N0 2 Scopolin crystallizes from petroleum ether or chloroform in prisms, melting at 110°, and boils at 241-243°. It is easily soluble in water and alcohol. It is a tertiary base and optically inactive. It appears to be related to tropin in the sense that a CH2 group of the latter is replaced by a CO group; it does not, however, give any reaction for ketone. It is possible to introduce different acid radicles into the tropin and scopolin molecule, thus forming a large number of derivatives known as tropeins and scopoleins. Thus we have products known as benzoyltro- pein; phenylacetropein, cinnamyltropein ; salicyltropein ; phenylglyco- lytropein or homatropin; acetylscopolein, benzoylscopolein, cinnamyl- scopolein, and many others, whose properties have been studied and constants recorded^ Homatropin, Ci 6 H 2 iN0 3 C 8 Hi 4 N0 -C0CH(0H)C 6 H 5 This product usually occurs in the form of its hydrobromide. It is prepared artificially and is the tropylester of phenylgly colic or mandelic acid. The base crystallizes from ether in glassy prisms, melting 92-98° according to different authors. Its mydriatic effect is as marked as that of atropin for about twelve to twenty-four hours and then subsides while the effect of atropin will often last a week. It is claimed to be less toxic. It is readily soluble in ether and chloroform. It is claimed to act similarly to atropin when tested with alcoholic mercuric chloride, but it does not give a purple color when tested by Vitali's reaction. It yields a precipitate with Mayer's reagent and a crystalline precipitate with picric acid, melting 180,5-181.5°, The aurochloride melts 142-145°. Euscopol This product is claimed to be inactive scopolamin hydrobromide, dif- fering from the ordinary scopolamin hydrobromide which is stated by the claimants to be a mixture of active and inactive salts. Distinguishing Tests. — From the descriptions of the individual mem- bers of this group the chemist will have no difficulty in distinguishing between the alkaloids. Their melting-points are well defined, their auro- chlorides and picrates furnish a ready means for their identification, and their crystalline salts are characteristic under the microscope. Allen states that Ladenburg employs the aurochlorides to separate the tropeins from each other. The atropin salt is the most insoluble and in fractional precipitation is thrown down first while the hyoscyamin salt is the most soluble. The alkaloids may be recovered by decomposing the ALKALOIDS DERIVED FROM PYRROLIDIN 113 aurochlorides with hydrogen sulphide, adding ammonia to the filtrate and agitating with chloroform and ether. Formulas where these alkaloids or their salts in the pure form play a part seldom if ever contain more than one individual, so that the chemist will have no occasion to effect their separation. He may, however, be called upon to separate atropin from strychnin, morphin, cocain, and pos- sibly quinin. We have seen that there are a great variety of mixtures in which the drugs belladonna, Hyoscyamus, scopola and stramonium are used, but here again the number of alkaloids from which the solanum bases must be distinguished are not numerous. Many of the ingredients in the mix- tures will be removable* from acid solution with immiscible solvents and others may be precipitated by lead salts. If morphin is suspected the product should be treated with sodium hydrate before shaking out with immiscible solvents from alkaline solution. The ether residue obtained by shaking out an alkaline solution should be the first one examined for this group as petroleum ether extracts but little atropin, most of the cocain if present going into this portion. The Vitali reaction should be tried on a portion and if no purple color is obtained on adding alcoholic potash there is no need of further testing, except to guard against overlooking homatropin. Antipyrin will interfere with this test and will be apparent if present when the mixture is evaporated with nitric acid, a deep purple developing at once and preventing any subsequent reaction with alcoholic potash ; and it should be remembered that a whoop- ing-cough mixture occurs containing both antipyrin and belladonna. Even if on adding alcoholic potash a purple color develops, one is not absolutely certain that atropin, hyoscyamin, or scopolamin are present, as strychnin gives the same color, impure coca bases do likewise, and the alkaloids of yohimbe, exploited now for the same purpose as strychnin, give a purple tint. - If cocain is present it would be apparent by the odor of ethyl benzoate, and a test with bichromate-sulphuric acid would show whether strychnin existed. If Vitali's reaction is performed with the chloroform residue in the presence of brucin, it is difficult if not impossible to obtain any purple color owing to the deep shades produced by nitric acid on brucin. Cocain may be separated partially from atropin, since it is so readily soluble in petroleum ether, two shakings being usually sufficient to remove it, while most of the atropin will remain to go later into the ether and chloroform fractions. Strychnin may be separated from the solanum bases by precipitating it out with platinic chloride in the presence of dilute hydrochloric acid, filtering, and then shaking out the tropeins from alka- line solution. Morphin, of course, will not be removed from a solution alkaline with sodium hydrate, but with opium present one must look for 114 ALKALOIDAL DRUGS codein, which fortunately does not interfere with Vitali's reaction, and no trouble need be anticipated from the presence of ipecac and Physostigma alkaloids or quinin. If it is possible to obtain sufficient of the gold salt and picrate in the pure condition to obtain melting-points, the analyst has an excellent con- firmatory test, and the microscopic appearance of the crystalline salts is conclusive. The question is sometimes asked, How can you distinguish between belladonna and scopola, the latter drug often being used in place of bella- donna? If the quantity of alkaloidal residue obtainable is in sufficient quantity, there ought to be no great difficulty in answering the question, for the presence of a considerable amount of scopolamin would be a strong proof that scopola had been used. The separation may be effected by the fractional precipitation of the gold salts and by a method recently described where the hyoscyamin is first thrown out by sodium bicar- bonate and after its removal the scopolamin is separated by potassium carbonate; though on the efficiency of this latter method the writer is unable to comment. Quantitative Methods. — In order to separate and determine the mixed bases when present in the form of the drug extract and when no other alkaloids are present the method described in the Pharmacopoeia should be employed. When the pure alkaloids alone are present, they may be separated by shaking out the alkaline solution with chloroform and the solvent solu- tion evaporated and weighed ; due precautions being taken as regards the manipulation, and removal of interfering substances, if present, from acid solution. When the drugs are mixed with other alkaloid-bearing drugs, pure alka- loids, or substances of a basic nature, one has to study the individual cases to effect a quantitative separation and in some* instances the deter- minations will be difficult if not impossible from an exact standpoint. The fact that the tropeins are held in solution when the platinum salts of the other alkaloids are precipitated in dilute acid solution may be used as a basis of many operations. Determination of Atropin in Tablets of Atropin Sulphate. — Weigh 25 tablets and introduce directly into a small separator. Moisten with 5 mils water. Add 1 mil stronger ammonia water. Agitate with 25 mils chloroform and allow to stand until separation is complete. Draw off the chloroform into a second separator and repeat the agitation twice more with 25-mil portions of the solvent. After combining all of the fractions, wash the combined chloroformic solutions by agitation with 10 mils of distilled water and allow to stand fifteen minutes. Introduce a pledget of absorbent cotton into the stem of the separator and run off the chloro- ALKALOIDS DERIVED FROM PYRROLIDIN 115 form into a tared dish, but do not allow the wash water to enter the orifice of the stop-cock. Add 10 mils chloroform and when the water has entirely risen to the surface, run off the chloroform into the tared beaker. Wash off the outer surface of the stem of the separator with a little chloroform and then evaporate over a steam or water-bath, using a fan or blower and removing from the bath as the last portions evaporate to avoid decrepi- tation. Dry to a constant weight in a vacuum desiccator and weigh as atropin. The weight of the atropin may be checked by dissolving the residue in neutral alcohol, adding an excess of N/10 sulphuric acid and titrating back with N/50 potassium hydroxide. Calculate to atropin sulphate 1 mil N/50 H 2 S0 4 = . 005741 gram atropin Factor for atropin to atropin sulphate 1.1695. BELLADONNA PLASTER U. S. P. Method Introduce 10 grams of Belladonna plaster into a 100-mil flask. (If the plaster is spread on fabric, cut the portion to be assayed into strips, weigh it accurately, and introduce into the flask.) Now add 50 mils of chloroform, and shake the mixture until the plaster is dissolved. Pour the chloroform solution into a 250-mil beaker and wash the cloth upon which the plaster was spread with two portions of 25 mils each of chloro- form, adding the washings to the chloroform solution in the beaker. Then wash this cloth with 80 mils of alcohol containing 1 mil of ammonia water and pour the washings into the chloroform solution in the beaker. Stir the mixture gently and allow it to stand until the rubber has separated into a compact mass. Dry the cloth upon which the plaster was spread, weight it, and subtract its weight from the original weight of the plaster. Pour the chloroform-alcohol solution into a 350-mil separator, rinse the beaker and rubber with 10 mils of alcohol and add the rinsing to the sepa- rator. Then add to the separator 100 mils of distilled water, rotate until thoroughly mixed and allow it to stand until the liquids separate. Then draw off the chloroform into a second separator containing 50 mils of dis- tilled water, shake it thoroughly and after separation draw off the chloro- form into a beaker and pour the aqueous solution into the first separator. Return the chloroform solution to the second separator and shake out the contents of the first separator with two portions of 10 and 5 mils, respectively, of chloroform, adding them to the chloroform in the second separator. Completely extract the alkaloids from the chloroform solution by shaking it out repeatedly with weak sulphuric acid. Collect the acid 116 ALKALOID AL DRUGS washings in a separator and add ammonia water until the solution is decidedly alkaline to litmus, and completely extract the alkaloids by shaking out repeatedly with chloroform. Filter the chloroform solution through a pledget of cotton, evaporate it to dryness, and dissolve the alka- loids from the residue in exactly 5 mils of N/10 sulphuric acid V. S., and titrate the excess of acid with N/ 50 potassium hydroxide V. S., using coch- ineal T. S. as indicator. Each mil N/10 sulphuric acid V. S. consumed corresponds to 28.92 milligrams of the alkaloids from belladonna leaves. Toxicological Testing. — In toxicological work the use of mineral acids should be avoided, the residues and organs being extracted with alcohol in the presence of acetic or tartaric acid. The alkaloids are best obtained by shaking out an ammoniacal solution with chloroform and if impure a second solution and extraction made. Atropin is rapidly absorbed by all parts of the bod}^ and distributed in the blood. 0.03 gram atropin after standing twelve years in contact with decomposing blood, beer, and other organic substances can still be detected. In case of suspected atro- pin poisoning the urine should be carefully examined. After taking into consideration the pharmacological action if it is pos- sible to ascertain it, one should apply Vitali's test to a portion of the residue, assure himself of the absence of strychnin with another, perform a physi- ological test on the eye of a cat with another, and obtain a sufficient quantity of the cr} T stalline gold salt and picrate to test under the micro- scope and obtain melting-points. To prepare a solution for pharmacological testing proceed as follows: Dissolve the residue in a small quantity of dilute acetic acid and evapo- rate cautiously over the steam-bath. Add solid sodium bicarbonate in small quantity until no longer acid, then filter into a clean tube or small flask and preserve carefully corked until ready to apply. ALKALOIDS OF THE POMEGRANATE TREE Pelletierin, C 8 Hi 5 NO. Isopelletierin, CsHnNO. Methylpelletierin, C 9 H 15 NO. Pseudopelletierin, C9H15NO. These four alkaloids and probably others occur in the bark of the pome- granate, Punica granatum (Punicacea?) . The barks of the root and stem comprise the drug, and the alkaloidal content ranges from 0.2-4 per cent. The bark is also rich in tannin. It is stated that the drug is sometimes adulterated with the root barks of the box (Buxus) and barberry. Neither pomegranate nor its alkaloids have a very extended use, so the drug analyst will seldom have occasion to identify or determine them. ALKALOIDS DERIVED FROM PYRROLIDIN 117 The drug has been successfully employed for the expulsion of tapeworm and hence should be sought for in anthelmintics. Pelletierin and isopelletierin may be separated from methylpelletierin and pseudopelletierin by treating an acid solution of the mixed bases with sodium bicarbonate, which liberates the two latter. They may then be removed by a suitable solvent, and the former subsequently liberated by strong alkali. Commercial pelletierin sulphate and tannate are mixtures of all of the pomegranate alkaloids. Pseudopelletierin is the only one of the group that has been carefully studied constitutionally. Pelletierin Pelletierin, also known as punicin, is a colorless oily liquid when freshly prepared, but becomes dark and resinous on exposure to air. It has spe- cific gravity 0.988 at 0°, is dextrorotatory, becoming inactive when heated to 100°, and its salts are laevorotatory. It boils at 195° with some decom- position. It is somewhat soluble in water and dissolves readily in alcohol, ether, and chloroform, and slightly in petroleum ether. It gives pre- cipitates with all of the ordinary alkaloidal reagents except platinic chlor- ide. It gives no characteristic color tests with strong acids or oxidizing agents. The residue obtained on evaporating a solution of pelletierin in strong nitric acid gives a strong mousy odor on treatment with alcoholic potash. Isopelletierin is probably a stereoisomer of pelletierin; it resembles this base in all its properties except that it is inactive. Methylpelletierin This is a liquid boiling at 215°, somewhat soluble in water and readily soluble in alcohol- ether and chloroform. Its hydrochloride is dextro- rotatory. Pseudopelletierin H2 H H2 c — c c 1 I V \ H 2 C N— CH 3 C=0 I ! / c — c c H2 H H2 Pseudopelletierin or n-methylgranatolin stands in close relationship chemically to the tropa alkaloids. Its oxygen atom is ketonic and it yields an oxime with hydroxlamine. With sodium and alcohol the C=0 group is converted into CHOH and methylgranatolin results, melting at 100°. The latter base on treatment with alkaline permanganate loses the CH3 group and becomes granatolin, melting 134°. 118 ALKALOIDAL DRUGS The alkaloid forms prismatic crystals, melting at 48°, inactive, readily soluble in water, alcohol, ether, chloroform, and slightly in petroleum ether. It is claimed that this alkaloid is not an anthelmintic. THE COCA ALKALOIDS AND SYNTHETIC ANESTHETICS The leaves of Erythroxylon coca and E. truxillense (Erythroxylaceae) contain the following alkaloids: Cocain, C17H21NO4. Cinnamyl cocain, C19H23NO4. Alpha Truxillin, (Ci 9 H 23 N04)2. Beta Truxillin, (CigEfeNO^. Benzoyl Ecgonin, C16H19NO4. Tropacocain, C15H19NO2. Hygrin, C 8 H 15 NO. Cuscohygrin, C13H24NO2. Coca grows in Peru and Bolivia in large quantities and less in Ecuador, Colombia, Brazil, and Argentine. It is also cultivated in the West Indies, Ceylon, Java, Zanzibar, and Australia. There are two classes of Coca leaves used commercially, the wide and the narrow. The former includes the Bolivia, Huanoco, Munzon, and Cusco varieties and the latter the Truxillo. The wide leaf is the richest in cocain, containing 0.3 per cent 0.8 per cent total alkaloids, 70 per cent to 90 per cent of which is cocain. The narrow leaves run from 0.3 per cent to 0.9 per cent total alkaloids, about 30 per cent to 50 per cent of which is cocain. Large quantities of crude cocain are shipped into commerce from South America, the material being refined by manufacturers in this country and elsewhere. An extract of the drug is used in some medicines designed for gastric and intestinal indigestion, malassimilation of food, in cachexias, as a stimu- lant and general tonic in cases of fatigue and weakness, and to combat the effects of opium and alcohol. The chief ingredient, cocain, is a local anesthetic and has a wide use. It is employed in surgery, ophthalmic practice, and dentistry, and it was formerly sold to the public in large quantity in the form of asthma cures, hay fever remedies, catarrh snuffs, and dope cures. Extract of Coca is often found combined with extracts of celery and kola in form of elixirs, to which other extracts are sometimes added, as Viburnum. In wines it occurs combined with beef extract and with iron. It is also found in combination with malt extract. Prior to the passage of the Food and Drugs Act, Coca extract, with its full content of alkaloids, ALKALOIDS DERIVED FROM PYRROLIDIN 119 was used as an ingredient of popular soft drinks, where it functionated in combination with Kola extract and caffein. The practice ceased several years ago. Solid extract of coca is an ingredient of some aphrodisiac pills, being mixed with phosphorus, Nux Vomica, and often cinchonidin; and in sedative compounds with valerian, Cannabis sativa, arsenic, strychnin, and occasionally codein. Cocain in the form of its salts occurs in tablet triturates, dental and ophthalmic tablets, often combined with morphin and atropin, and in various compressed tablets, one of the most important being a throat tablet where it is present with menthol, benzoic acid, eucalyptol, and oil of anise. Again it is combined with borax and potassium chlorate in voice tablets. Cocain — (Methyl — benzoyl — ecgonin) CH 2 CH CHCOOCH3 I \ N— CH3 CHOOCCoHs I / CH2 CH CH2 Cocain occurs in all Coca leaves. It crystallizes from alcohol in 4- to 6-sided prisms melting at 98° C. It has a slightly bitter taste and numbs the nerves of the tongue. When the tongue or lips have been rubbed with the alkaloid they gradually become numb and feel smooth like ivory until the effect wears away. It is soluble in 700 parts water at 12° C, 10 parts alcohol, and 4 parts ether, and is also soluble in benzol, toluol, carbon bisulphide, carbon tetrachloride, chloroform, petroleum ether, acetic ether, amyl acetate, ace- tone, kerosene, aniline, turpentine, olive oil. It is insoluble in glycerin. It turns the plane or polarized light to the left [a]d — 71° 95'. It is a monoacid base and is readily soluble in dilute acids. It is alka- line to litmus and methyl orange, but does not affect phenolphthalein. Its aqueous solutions are precipitated by ammonia, alkalies and alkali car- bonates. It is precipitated by potassium ferrocyanide, all of the general alka- loidal reagents, Mayer's, Wagner's, tannic acid, phosphomolybdic acid, platinum chloride, gold chloride, by chromic acid on acidulation, by zinc sulphocyanide, by palladium chloride in presence of chlorine water, by mercuric acetate, the precipitate being soluble in excess on standing, but is not precipitated by potassium ferricyanide. It forms with bismuth a double iodide and gives an oily precipitate with potassium bichromate. Boiling water hydrolyzes cocain to benzoyl-ecgonin and methyl alcohol, while by alkalies it goes to ecgonin and benzoic acid. It is completely 120 ALKALOIDAL DRUGS hydrolyzed to ecgonin, benzoic acid, and methyl alcohol by heating for several hours in a pressure flask over the steam-bath. Cocain gives no characteristic color reactions on which any reliance can be placed when working with small quantities. The physiological test is characteristic, though of course other sub- stances produce anesthesia, and this alone will not identify cocain. When moistened with nitric acid and evaporated to dryness, the resi- due on addition of a few drops of alcoholic potash will give the odor of ethyl benzoate. This odor cannot be mistaken, but it disappears quickly if the amount of the alkaloid is small and hence caution must be used in applying the test. If the odor of the alcohol is confusing, a little water should be added and the contents heated. This is one of the best tests for cocain, quantities as small as .2 mg. being readily detected. The pro- cedure is that of Vitali for the detection of atropin, which gives a beautiful violet color. Tropacocain will also give the ethyl benzoate odor. Hyos- cyamin, strychnin, codein, and physostigmin give color reactions and the latter develops an odor resembling phenyl-isocyanide. Delphinin, brucin, and veratrin develop slight odors which, however, cannot be mistaken for ethyl benzoate. Until perfectly familiar with this odor a parallel test should be made using a sample of cocain. On heating cocain with dilute hydrochloric acid under pressure for four hours over steam, the odor of methyl benzoate can be detected on opening the flask. Tropacocain gives no such odor. On heating cocain with dilute hydrochloric acid containing a few crys- tals of salicylic acid, under pressure over the steam-bath, a marked winter- green odor will be apparent on opening the tube. This test will distinguish cocain from tropacocain. If 2 to 3 mils of chlorine water are added to a cocain solution and then several drops of 5 per cent palladium chloride solution are added, a red precipitate is formed which is insoluble in alcohol and ether, but soluble in sodium thiosulphate. On adding 5 drops of a 5 per cent chromic acid solution to a cocain solution, a yellow precipitate will be formed which disappears on shaking. On the addition of 1 mil of concentrated hydrochloric acid a permanent yellow precipitate is formed. If truxillin is present reduction of the chro- mic acid takes place. Ecgonin, spartein, atropin, caffein, pilocarpin, codein, and morphin do not form yellow precipitates with chromic acid or potassium chromate. Quinin, quinidin, cinchonin, cinchonidin, hydro- quinin, apomorphin, brucin, strychnin and veratrin form precipitates with 5 per cent chromic acid if the solutions are neutral, but cocain only gives the precipitate after the addition of hydrochloric acid. A solution containing not less than 1 per cent cocain gives a copious red precipitate on the addition of potassium permanganate. The behavior ALKALOIDS DERIVED FROM PYRROLIDIN 121 with permanganate serves also to detect an admixture of cinnamyl-cocain and certain other impurities. The presence of these causes an immediate reduction in the cold, the first drop or two of the reagent produces a brown coloration, while the precipitate produced by a further addition is more or less brown instead of a violet red. Cocain is removed from an ammoniacal solution by all of the immis- cible solvents. In the case of caustic alkalies where the mixture has been heated and subsequently cooled, the cocain will not come out to any extent. However, attempts to make use of this property as a means of separating quinin from cocain have so far led to unsatisfactory results. Cocain is easily broken down by evaporating it in acid or alkaline solution or even boiling it with water. Cocain Hydrochloride Cocain hydrochloride is the principal commercial salt of this alkaloid. It occurs in the form of prismatic crystals or lustrous leaflets and is readily soluble in water and alcohol. If 5 mils of a 1-50 solution in water are treated with 85 mils of water and .2 mil ammonia water (10 per cent), and vigorously stirred with a glass rod, a crystalline precipitate will form within a short time and the supernatant liquid will be clear. This is the cus- tomary reaction taking place when the salt is pure and is known as Mac- Lagan's test. The presence of 0.5 per cent of allied coca bases will pre- vent the formation of a crystalline precipitate and the liquid will retain a milky appearance Cinnamyl Cocain CH 2 CH CHCOOCH3 I \ NCH3 CHOOCCH=CHC 6 H 5 I / C H2 C H C H2 Methyl-cinnamylecgonin This alkaloid is found in all varieties of coca, particularly in that from Java, of which it constitutes one-half the total alkaloids. It melts at 121° C, is readily soluble in alcohol, benzol, and ether, and sparingly soluble in petroleum ether, but is almost insoluble in water. Its solutions are lsevorotatory. It instantly reduces solutions of potas- sium permanganate and the odor of benzaldehyde is given off on warming. On heating over the steam-bath under pressure in presence of acid it is easily decomposed into cinnamic acid, ecgonin, and methyl alcohol. It does not give the ethyl benzoate test which is so characteristic of cocain, the ester formed in this case having the odor of ethyl cinnamate. 122 ALKALOIDAL DRUGS Furthermore, on evaporating with nitric acid the odor of benzaldehyde is apparent. Cocain may be readily separated from cinnamyl cocain on account of the ease with which the latter is oxidized by permanganate, in fact experi- ments conducted by Garsed show that the cocain can be recovered quanti- tatively. CH 2 — CH- I Alpha and Beta Truxillins C 6 H 5 CH3COOCH — CH I / I CHCOOCH3 CH— CH— COOHC NCH 3 \ II \ I NCH 3 CHOOC CH— C 6 H 5 CH 2 — CH — I / CH2 — CH CH2 CH 2 — CH CHCOOCH3 NCH 3 CHOOC— CH— CH— C 6 H 5 I / II -CH 2 -CHc CH 2 CH 2 — CH CH 2 CH — CH — C6H5 CH 2 — CH -CHCOOCH3 I \ NCH3 CHOOC — I / CH 2 — CH CH 2 Alpha truxillin, cocamin, isatropyl-cocain, as it is variously called, is amorphous. It melts at 80° C, is little soluble in water and petroleum ether, but soluble in the other organic solvents. Its solutions are laevo- rotatory. It is quite bitter. Beta truxillin possesses similar properties, it is amorphous and begins to melt at 45° C. It differs from the alpha by its slight solubility in alcohol. The acid products of hydrolysis, cocaic, isatropic, or truxillic acids are polymers of cinnamic acid and on distillation are converted into this acid. They do not absorb halogens and on oxidation do not yield benzaldehyde, hence they have no double bond. They are much more insoluble in water than either benzoic or cinnamic acids and may be separated from them by simply filtering an aqueous solution which is sufficiently dilute to hold up the benzoic and cinnamic acids. The truxillins are not oxidized by permanganate and may be separated from cinnamyl-cocain in a manner similar to cocain. In order to identify the cocain in a mixture of the same with cinnamyl cocain and the truxillins, the solution should be treated with perman- ganate. The benzoic acid formed in this reaction may be removed by shaking out from acid solution with ether and then the residual solution ALKALOIDS DERIVED FROM PYRROLIDIN 123 heated for three or four hours in a pressure flask over the steam-bath. By evaporating to a dilution of about 1-400 the benzoic acid will remain dissolved when cooled to 12° C, while the truxillic acid will be almost completely separated. The solution may be filtered and the clear filtrate shaken out with ether, which will remove the benzoic acid formed by the hydrolysis of the cocain. It can then be identified by its melting-point and other characteristic tests. Benzoyl Ecgonin CH 2 — CH CHCOOH I \ NCH3 CHOOCC 6 H 5 I / CH2 — CH CH2 This substance exists naturally to some extent and results from the partial saponification of cocain. It is soluble in water and alcohol but only slightly soluble in ether. The hydrous form melts at 90° C. and the anhydrous at 195° C. It is soluble in alkalies. Tropacocain. Benzoyl Pseudotropin CH 2 — CH CH 2 I \ NCH3 CHOOCCeHs I / CH 2 — CH CH 2 This alkaloid crystallizes from ether in plates having a melting-point of 49° C. It is insoluble in water, but dissolves in alcohol and follows cocain very closely in solubility in the organic liquids. On hydrolysis with dilute mineral acids it splits up into benzoic acid and pseudotropin. It gives precipitates with the general reagents for alkaloids. With potassium bichromate it yields a crystalline precipitate instead of the oily residue given by cocain. A few drops of a 5 per cent solution of chromic acid precipitates at once a solution of a tropacocain salt. When a mixture of the salts of both cocain and tropacocain are treated with 5 per cent chromic acid the tropacocain is precipitated at once and agglomerates, sticking to the side of the tube. On filtering and adding hydrochloric acid to the filtrate, a copious precipitate characteristic of the cocain compound is formed. It gives a precipitate with mercuric acetate which does not go into solution again on standing as in the case of cocain. With potassium ferricyanide it gives a precipitate of needle-like crys- tals gradually appearing. Cocain does not precipitate with this reagent. Hesse states that on account of its solubility in dilute ammonia it may be separated from the other coca alkaloids. 124 ALKALOIDAL DRUGS Hygrin This is a liquid having a boiling-point of 193-195° C. It is a tertiary base, contains a N methyl group but no methoxyl. Its oxygen is ketonic in character, since it forms an oxime which can be distilled almost un- changed. It is easily soluble in alcohol, but wLh difficulty in water, ether, and petroleum ether. It is decomposed by light. On oxidation with chromic acid, monbasic hygric acid, C5H10NCOOH, results, which crystallizes with one molecule of water and melts at 164°. It absorbs carbon dioxide from the air and also forms a hydrochloride and a hydroiodide. It gives a well-defined needle-like picrate melting at 148°. (160° Beilstein.) Lieberman claims that hygrin occurs chiefly in the Cusco leaves, where it is present to about 0.2 per cent. As obtained from coca leaves hygrin is not a substance of definite com- position, but consists of a mixture of liquid bases which can be separated from each other only with difficulty. To prepare hygrin, according to Lieberman and Cybulski, 200 grams of impure hygrin obtained from Cusco leaves were strongly acidulated with 150 mils 33 per cent hydrochloric acid to decompose the acylecgonin present and boiled for one hour on the water-bath with an air cooler, the acids were separated with ether and then 250 grams concentrated potas- sium hydroxide (2-1) added, and the bases dissolved out with ether. The ether solution was washed with caustic alkali or with barium hydroxide, the ether then distilled and the residual oily bases fractionated. Hygrin goes over between 92-94° at 20 mm. pressure, or at 111-113° at 50 mm., specific rotation [a] D — 1.3°. The high boiling constituent of the basic mix- ture consists, according to the authors, of cuscohygrin and /3-hygrin. The presence of hygrin and cuscohygrin in extracts of dried coca leaves is a matter of controversy at the present stage of our knowledge of this class of alkaloids. That they occur in the fresh leaves has been definitely ascertained, and from work done on the extracts of dried leaves it is prob- able that they exist there also, but further experimental research into the phytochemistry of the drug is needed before the obscure points can be definitely settled. Dr. Rusby after an extended research on the subject of the coca leaf was satisfied that, before exportation, the drug contained a much higher percentage of alkaloid. It is his belief that during transit the leaves lose some volatile substance, perhaps hygrin.- Cuscohygrin This is also a liquid of oily nature and boils at 185° C. at 32 mm. It is easily soluble in water, forms a hydrate which melts at 40-41° C, and a well-defined nitrate which permits its separation from hygrin. ALKALOIDS DERIVED FROM PYRROLIDIN 125 It is a di-acid tertiary base with a methyl group attached to each nitrogen. PRODUCTS OF HYDROLYSIS OF THE PRINCIPAL COCA ALKALOIDS On heating the alkaloids to 80-100° C. with hydrochloric acid prefer- ably under pressure, or boiling with alcoholic potash they act as follows: Cocain, C17H21NO4+H2O = C16H19NO4+CH3OH Benzoyl ecgonin then C16H19NO4+H2O = CgHisNOs+CeHsCOOH Ecgonin ' Cmnamyl Cocain, C19H23NO4+H2O = C18H21NO4+CH3OH Cinnamyl Ecgonin then C18H21NO4+H2O = C9H15NO3+C9H8O2 Ecgonin Cinnamic Acid Truxillin, C38H46N 2 Og+3H 2 = C9H15NO3+C27H29NO6+2CH3OH then C27H 2 9N0 6 +H 2 = C9H15NO3 + C18H16O4 Ecgonyl cocaic acid Truxillic acid Tropacocain, C17H19NO2+H0O = CsHisNO+CeKsCOOH Pseudotropin The ease with which the Coca alkaloids are decomposed is taken ad- vantage of in the commercial field. The mixed alkaloids are hydrolyzed, the resulting acids separated and then the ecgonin converted to cocain. Ecgonin is a solid substance containing one molecule of water melting at 198-199° C. It is readily soluble in water and its solutions are laevo- rotatory. It is soluble in ethyl acetate, slightly soluble in alcohol, almost insoluble in ether, and does not dissolve in acetone, chloroform, toluol, carbon bisulphide or carbon tetrachloride. / It acts as a tertiary base, a monatomic alcohol, and a monacid base. It forms quaternary salts, esters, and normal salts with alkalies which are not decomposed by carbon dioxide. Ecgonin solutions are neutral to litmus, a fact which caused Einhorn to suggest that the acid and basic elements in the molecule neutralized each other, yielding a betaine-like structure. At a dilution of 1-500 it is not precipitated by N/100 iodine, but stronger solutions yield precipitates with iodine. Ecgonin is not precipitated by potassium mercuric iodide, but forms a very insoluble compound with phosphotungstic acid. It is not removed from aqueous solutions by immiscible solvents except possibly to a slight degree by ethyl acetate. The identity of ecgonin is best established by converting it to cocain and isolating and identifying the alkaloid. The material under exami- nation should be brought into solution, made slightly alkaline with caustic alkali and the alkaloids removed by agitation with Prolius mixture. The 126 ALKALOIDAL DRUGS extraction must be continued as long as any substance is removed which will give a precipitate with Mayer's reagent. If the solution is a plant extract or contains any quantity of foreign matter, it is then neutralized with acetic acid and treated with an excess of Howe's basic lead acetate. After filter- ing, the excess of lead is removed by potassium oxalate, the filtrate evap- orated and the residue thoroughly extracted with pure anyhdrous methyl alcohol. The alcohol solution is warmed, subjected to the action of dry hydrochloric acid gas for about ten minutes, heated again and the treat- ment with hydrochloric acid repeated, this procedure being continued, adding more methyl alcohol if necessary, for about one-half hour. The mixture is then transferred to a larger and long thick test-tube, the alcohol evaporated, benzoyl chloride added, and the tube heated in an oil-bath at 180-200° C. for one-half hour. At the end of this time the tube is cooled and the contents washed out with ether and sodium bicarbonate solution. After agitation with three portions of ether, the combined solvent solutions are shaken out with dilute sulphuric acid, the acid sepa- rated, made alkaline with sodium bicarbonate and agitated with low- boiling petroleum ether, which will dissolve any cocain which may have been formed, and on evaporating the solvent the residue can be subjected to the identity tests for that alkaloid. On boiling with baryta Water methylamine is formed. On treatment with phosphorus pentachloride a molecule of water is lost and anhydroecgonin is formed, which is soluble in water and alcohol but almost insoluble in ether. On heating with hydrochloric acid, carbon dioxide is given off and tropidin formed. Several stereoisomers of ecgonin have been prepared synthetically. ^ Pseudotropin forms crystals melting at 106° C, boiling 241-243° C. \ Soluble in water, chloroform, alcohol, but sparingly soluble in ether. By heating with glacial acetic acid and sulphuric acid tropidin results. The truxillic acids have already been discussed to some extent under the truxillins. They are not volatile with steam, as are both benzoic and cinnamic acids, and are much more insoluble in water, dilutions of 1-40,000 giving a distinct precipitate. Truxillic acid melts at 274°. Iso-truxillic acid melts at 206°. The acid is nearly insoluble in ether, from which it crystallizes in a form resembling benzoic acid. The barium salt of alpha-truxillic acid is soluble in water, while that of the beta acid is insoluble. The alpha acid is obtained in about double the amount of the beta. The alpha acid on treatment with acetic anhydride and subsequently with a base is converted into an isomeric acid called gamma-truxillic acid. The beta acid on fusion with alkali is converted to delta-truxillic acid. ALKALOIDS DERIVED FROM PYRROLIDIN 127 IDENTIFICATION OF THE COCA ALKALOIDS The analyst of galenical preparations will be called upon to detect the presence of cocain in liquid preparations containing extract of coca leaf and in preparations where it is used as a salt of the pure alkaloid, also to differentiate between it and other alkaloids and various anesthetics of synthetic origin. As cocain is the chief active ingredient of coca leaf, except possibly that of East Indian origin, little difficulty need be experienced in substan- tiating its presence in products containing the extract. If by chance one is working with a product where the amount of cinnamyl cocain predomi- nates, the fact that this latter alkaloid is in large quantities may be readily ascertained from a knowledge of its properties taken into consideration with those of cocain, and if the cinnamyl cocain is found it may be removed by making use of the permanganate reaction. As obtained from a drug extract the alkaloidal residue is seldom crystal- line, but has the consistency of a thick oil. If the final extraction has been made with low-boiling petroleum ether, the residue will often crystallize on standing overnight. The deposit is usually without color, but it has a characteristic odor. It has no color reactions on which any reliance can be placed, but its character may be readily determined by placing a bit on the end of the tongue and rubbing it gently for about a minute. A sen- sation of numbness develops gradually, the tongue and often the lips which have been touched by the finger will have a smooth, ivory-like feeling, and the effect will be apparent for some time. The residue will give the ethyl benzoate test, and by proceeding accord- ing to the method of Garsed described on a subsequent page for determin- ing the alkaloids, a separation and identification of the cocain, cinnamyl cocain, and the truxillins may be accomplished. Ecgonin and benzoyl ecgonin are so soluble in aqueous liquids that they are not removed by ether. Aconitin will also give the ethyl benzoate test, but it is seldom if ever found with coca alkaloids, and the physiological test would establish its presence at once. From a solution or other preparation where cocain is present in the form of a pure salt, the alkaloid will be obtained, when not mixed with other alkaloids, in a form which is usually crystalline and which gives a sharp melting-point. In all cases the alkaloid should first be brought into a solution slightly acid and free from alcohol. The solution should first be shaken out with ether and chloroform, then made ammoniacal and shaken out with low-boiling petroleum ether. The petroleum-ether solution should be separated, filtered into a small beaker or dish, and evaporated over the steam-bath. The residue, if pure cocain, will give its character- istic reactions, 128 ALKALOIDAL DRUGS Tropacocain in the form of its pure salt is used medicinally, though not to any great extent. It may be readily distinguished from cocain by its melting-point, by not giving the methyl salicylate test, by its immedi- ate precipitation by 5 per cent chromic acid from neutral solution, by its precipitation with potassium ferricyanide, and by the permanence of the precipitate formed with mercuric acetate. Other common alkaloids which might be removed simultaneously from an ammoniacal solution by means of petroleum ether, may be distinguished from cocain as follows: Coniin and nicotin may be eliminated, as they would almost never occur. However, the white fumes which develop by bringing a drop of hydrochloric acid on a glass rod near the surface of a residue containing them would be an indication of their presence. They are both volatile and would not interfere with the ethyl benzoate test. Atropin, which often occurs with cocain, would be detected by Vitalis color reaction, at the same time the ethyl benzoate test is performed. Quinin would be apparent by the intensely bitter taste of the residue, and the presence of cocain will not interfere with the thalleoquin reaction. The physiological test will show the presence of cocain. Caff ein does not interfere with the ethyl benzoate test, and the pres- ence of cocain does not harm the Murexide test for cafTein. Moreover, caffein would be removed by previously shaking out the acidulated solu- tion with chloroform, and again it is practically insoluble in petroleum ether. Morphin, while it is often used with cocain, would not appear in the petroleum ether shake-out. The distinguishing tests between cocain and the synthetic anesthetics will be described after a consideration of the properties of these substances. SEPARATION AND IDENTIFICATION OF SMALL QUANTITIES OF COCAIN If the substance under examination is a solid it should be dissolved in water, if possible, or in normal sulphuric acid: if it contains much drug material and is not readily dissolved in water an extraction with alcohol should be resorted to, water added to the mixture, and the bulk of the alcohol subsequently evaporated. Liquid products, such as sirups, need no prelimimary treatment unless they are very thick or in the form of emulsion; in the former case they should be diluted to about the consist- ency of a 50 per cent sugar solution, and in the latter some method which will separate the gum and fatty material must be adopted. Having obtained a clear solution of the substance in question the pro- cedure is as follows: Transfer the solution to a separator and add a slight excess of ammo- nium hydroxide. (If the product was originally alkaline it is best to acidify ALKALOIDS DERIVED FROM PYRROLIDIN 129 it and then add a slight excess of ammonia. If a precipitate is formed it should be separated by filtration and the filtrate used for analysis.) Shake out the solution with 50 mils of Prolius mixture (ether 4 parts, chloroform 1 part, and alcohol 1 part), and allow to stand; then Collect the clear solvent in another separator and shake out the aqueous solu- tion twice more with the Prolius mixture. Filter the combined solvent solutions through a creased paper into a beaker and evaporate the liquid over a steam-bath, using a fan. Do not allow the residue to dry, but as soon as the last portions of alcohol are driven off remove the beaker from the steam. Add 25 mils of normal sulphuric acid in 10-mil portions, warm the mixture slightly and then filter into a separator after each portion of the dilute acid is added, and finally wash with a little water. Then shake out the solution five times with 15-mil portions of chloroform, preserving the chloroformic extracts in another separator. Wash the latter with 10 mils of distilled water, discard the chloroform, and add the wash water to the acid liquid which was shaken out with the chloroform. Then add 10 mils of petroleum ether (boiling at 40°-60° C.) and thoroughly shake the separator, separate the acid liquid, and discard the solvent. Add a slight excess of ammonium hydroxide, cool the mixture, and then shake out the solution with 15 mils of petroleum ether of the boiling-point before specified and reserve the solvent solut on in another separator. Shake twice again with the same quantity of solvent, ^hen wash the combined petroleum ether solutions once with distilled water and filter into a small beaker, washing the separator and filter with 10 mils of petroleum ether. Evaporate the petroleum ether rapidly over a steam-bath, using a fan, and if cocain was present in the original material it will be found in the residue. By this method it is possible to obtain the cocain in a very pure con- dition; in fact, it will often crystallize in a few hours, even though the amount present be very small. The identification tests are conducted as follows : Dissolve the residue in petroleum ether and pour p )rtions of the sol- vent into a beaker and a small evaporating dish, reserving the remainder for subsequent tests. After the solvent has evaporated dissolve the con- tents of the beaker in 5 mils of normal sulphuric acid, warming if necessary, and add potassium mercuric iodide test solution. The formation of a precipitate indicates the presence of an alkaloid, but, of course, does not identify it as cocain; if no precipitate occurs further tests are unnecessary. To identify the alkaloid treat the contents of the evaporating dish with 2 mils of concentrated nitric acid and evaporate the mixture to dry- ness over the steam-bath. When there is no further odor of nitric acid remove the dish, cool, and add 5 to 10 drops of N/5 alcoholic potash 130 ALKALOIDAL DRUGS solution, noting carefully the color and odor of the mixture while the dish is cool and then applying gentle heat and noting the odor again. Minute traces of cocain will give off the odor of ethyl benzoate on treatment with nitric acid and alcoholic potash. The odor is very marked in its character and can be readily distinguished, though until one is familiar with it a parallel test should always be run, using pure cocain. The color reaction is also of interest and will prove valuable in detect- ing the presence of other alkaloids. A purple color would indicate that atropin, strychnin, or yohimbin were present, though it is well known that a residue obtained by the above method from the coca leaf will in some instances also give a purple color. Tropacocain, benzoylecgonin, and aconitin will also give the ethyl benzoate test, but the possibility of the presence of the first two can be eliminated by a subsequent micro- scopic test, and from the fact that the benzoylecgonin is not removed from the aqueous solution to any great extent by petroleum ether. The latter fact is also true of aconitin, but the presence of this very poisonous alkaloid would be readily apparent when performing the physiological test. The portions of the material which had been reserved should be tested physiologically. The petroleum ether is evaporated, a part of the cool residue is placed on the tongue and rubbed gently with the finger for about one minute, when, if cocain is present, a sensation of numbness gradually develops, the tongue and often the lips which have been touched by the finger will have a smooth, ivory-like feeling, and the effect will be apparent for some time. This is another test which should be performed in con- junction with one on a known sample, unless the analyst is perfectly familiar with the sens tion. This residue may also be used "or a microscopic test by removing a small portion, placing it on a microscope slide and noting, under the lens, the character of the crystals found with a drop or two of gold chloride solution. Cocain forms a definite crystalline compound with gold chlo- ride, and the product obtained should be compared with that given by a solution of the pure alkaloid. With a residue obta ned originally as described, these tests will sub- stantiate the presence of cocain even though it occur in a minute quantity, and the four reactions can be applied to very small residues, although if it is desired the first mentioned with potassium-mercuric iodide may be omitted. Another reaction for cocain which is very characteristic when con- sidered in conjunction with the ethyl benzoate test is obtained by trans- ferring some of the residue to a pressure flask, adding a few crystals of salicylic acid and about 15 mils of dilute hydrochloric acid, and heating the flask, stoppered, for about an hour and a half over the steam-bath. ALKALOIDS DERIVED FROM PYRROLIDIN 131 On opening the flask the odor of wintergreen will be very marked if cocain was originally present. Tropacocain does not respond to this reaction, though it might indicate the presence of cinnamyl cocain and the truxil- lins; all of the latter, however, are precluded if the mixture gives the ethyl benzoate test. Howard and Stephenson 1 describe the results of their researches in determining the characteristic microscopic forms of the crystals of a number of cocain salts, and the essential points of the work are summarized as follows: Crystalline deposits have been obtained with each of the following eleven reagents, viz., palladous chloride, platinum chloride, gold chloride, picric acid, chromic acid and hydrochloric acid, potassium dichromate and hydrochloric acid, potassium permanganate, potassium chromate, sodium carbonate, ferric chloride, and potassium hydrate or sodium hy- drate; noncrystalline deposits were obtained with chlorzinc iodid, picra- lonic acid, Mayer's reagent, phosphomolybdic acid, phosphotungstic acid, Kraut's reagent, Wagner's reagent, barium mercuric iodide, and potas- sium cyanide. The following observations were noted concerning the various react- ions with cocain in which crystals were produced: Palladous Chloride — Tins is one of the most characteristic tests for cocain, though not quite so sensitive as gold chloride. The crystals vary in form greatly, according to the conditions of precipitation. There is at first formed, except in very dilute solutions (1 : 300 and up), an orange- colored amorphous-like or oily precipitate from which, on standing, crys- talline forms of golden-brown color are produced. One of the most com- mon forms is that obtained with a 1 : 100 dilution, when feathery crystals are formed which have a strong tendency to twin. With a solution of 1 : 20 a dense precipitate is thrown down, out of which hexagonal plates are at first formed and frequently followed later by sheaf-like clusters of fine-pointed acicular crystals. A dilution greater than 1 : 500 gives crys- tals only with difficulty, crj^stalhzation being induced by rubbing the slide with the glass stirring rod. The limit of the test is 0.2 /* gr. Platinum Chloride. — With a 1 : 20 solution a dense white precipitate is formed and quickly followed by the production of veiy narrow feathery crystals — many times twinned so as to resemble a bird with outspread wings. Clusters of more than two are also abundant. If the reagents are mixed slowly the crystals are more like those of greater dilution. With a 1 : 100 dilution the feather type is much more prominent, the secondary branches being well developed into frost-like forms. With 1 : 1000 solu- tions either short thick crystals are formed or else plate crystals twinning 1 U. S. Dept. Agri. Bull. 122, Bureau Chemistry, p. 99. 132 ALKALOIDAL DRUGS in a most characteristic manner are produced. The dilution limit is about 1 : 4000, and the limit in 1 : 1000 is 0.2 M gr. Gold Chloride. — This is the most sensitive reagent for cocain so far found. At 1 : 100 feathery frost-like crystals are produced, together with some nearly smooth star-like aggregates. At 1 : 1000 the form is much the same, but the branches usually bear a rough outline. Diamond plates are also produced. At 1 : 4000 a cross-like form predominates, the cross- bar being short. A few rosette crystals frequently are present. Crys- tals can be obtained in dilution up to 1 : 20,000, and the limit of the test for dilutions of about 1 : 300 is 0.033 fi gr. Picric Acid. — This is a good reagent for dilutions up to 1 : 800, though the crystals produced are not very characteristic for this alkaloid. They are produced in spherical rosettes (or sheafs) of fine lemon-yellow acicu- lar forms. The reaction takes place quickly, and no difficulty is experi- enced in producing them nearly to the hmit of dilution. At 1 : 300 the limit is 0.2 /i gr. Potassium Permanganate. — With cocain, solutions up to a dilution of 1 : 700 give purple-colored square plates, or aggregates of this form. Vigorous rubbing of the slide is often necessary to start the crystallization, which then proceeds readily. When they begin to crystallize sponta- neously, the plates are sometimes deposited in spherical aggregates, The limit at 1 : 400 is 2 M gr. Chromic Acid and Hydrochloric Acid. — This test is made by adding a small drop of 5 per cent chromic acid solution to the test drop. A pre- cipitate is formed which on stirring disappears (if too much has not been added). A small drop of strong hydrochloric acid is added, and a yellow- ish deposit is produced which, after rubbing of the slide, should in a few moments be transformed into loose spherical clusters of an acicular crys- tal. This test appears to be one of the most uncertain, because of the chfficult}^ with which the crystallization is sometimes induced to being in dilutions greater than 1 : 60. A concentration of 1 : 1000 has produced positive results on standing several minutes. The limit appears to be for 1 : 100 about 3 M gr. Potassium Bichromate and Hydrochloric Acid. — This test gives the same form of crystals as the chromic acid and the test is conducted in a similar manner. The hmit of dilution is about 1 : 1000 while at 1 : 100 the limit is 3 y. gr. Ferric Chloride. — The crystals are spherical aggregates of rather coarse blade-like crystals with chisel-shaped ends. The limit of dilution is about 1 : 1000 and in a dilution of 1 : 100 the hmit is 3 \i gr. Potassium Hydrate, or Sodium Hydrate. — This produces a white amor- phous precipitate which changes into crystals on standing or by rubbing the slide w T ith a glass rod. The crystals are rod-like, frequently with more ALKALOIDS DERIVED FROM PYRROLIDIN 133 or less chisel-like ends and a V-shaped recess extending backward into the crystal. There is a strong tendency to form coarse clusters up to about fifteen branches. In open drops tree-like forms are frequent. For each of these reagents dilutions up to 1 : 1000 give the reaction and the limit at 1 : 100 is 3 m gr. Sodium Carbonate. — This gives a precipitate with cocain like that produced by potassium hydrate, both in the amorphous and crystalline forms. Limit of dilution is 1 : 1000. In 1 : 100 solution the limit is 3 n gr. In order to determine the usefulness of some of the above tests when other alkaloids are present the palladous chloride test was made on test drops to which had been added solutions of one of the following alkaloids : codein sulphate, atropin sulphate, heroin, dionin, acoin powder, cinchonin sulphate, hydroxylamin hydrochloride, apomorphin hydrochlorate, narcotin, papaverin, brucin, narcein, morphin, thebain, gujasanol, orthoform (new), cinchonidin sulphate, quinidin sulphate, beta-eucain, holocain, caffein, quinin sulphate, strychnin, and tropacocain. In each case the crystals of the cocain compound were obtained and in the case of brucin, gujasanol, caffein, strychnin, and tropacocain, with which the palladous chloride regularly gives a crystalline precipitate, it was found that when cocain was also present the cocain product was given in addition to that for the other alkaloid, though occasionally with modified form, QUANTITATIVE DETERMINATION OF ALKALOIDS IN COCA EXTRACTS AND SEPARATION OF COCAIN The alkaloidal residue obtained in the assay of coca leaf or the extract made from this drug does not show the actual cocain content. This alka- loid may be present to the extent of 40-90 per cent. From solutions containing extract of Coca, and where the Belladonna or Cinchona alkaloids are not present, the Coca alkaloids may be separated in the same way as they are from the extract obtained from the drug in the assay methods. Caffein may be separated from cocain by taking advantage of the fact that the former can be removed by chloroform from solution acidulated with sulphuric acid. The methods for determining the ether soluble alkaloids in Coca leaf have already been detailed. In order to determine the actual cocain present in the alkaloidal residue obtained in the assay of Coca leaf or preparations containing this drug the following method of Garsed l may be used : The crude alkaloids, after thoroughly drying over sulphuric acid, are weighed. Then dissolve in dilute sulphuric acid and add potassium per- 1 Pharm. J., 1903, 784. 134 ALKALOIDAL DRUGS manganate solution. Re-extract the unoxidized alkaloid from ammonia- cal solution with ether, evaporate the solvent, dry carefully and weigh. The loss in weight represents the amount of cinnamyl cocain. Subject the residue to alkaline hydrolysis as follows: Use about 20 mils N/10 alcoholic potash to every 0.1 gram of residue. Add to the mix- ture 20 mils distilled water and heat for half an hour on the water-bath, using a reflux condenser. Any volatile ester formed is, at this dilution, rapidly hydrolyzed. Evaporate alcohol, dilute with water to about 10 mils, place in a separatory funnel and wash with ether. Add a slight excess of normal acid and extract three times with ether. Separate and evaporate ether extracts at a temperature below the boiling- point of ether. Add distilled water until a dilution of 1 : 500 is obtained and temperature kept at 14° C. Under these conditions the truxillic acid remains undissolved. Filter and wash thoroughly with water at 14°. Determine the benzoic acid in the filtrate by shaking out with ether and then separating the ethereal solution, adding to it in a separatory funnel a known volume of N/ 10 or N/ 50 alkali, extracting thoroughly and titrat- ing the excess of alkali with N/10 or N/50 acid. From the figures obtained the amount of benzoic acid and from that the amount of cocain can be calculated. Wash out the dish used in separating the benzoic from the truxillic acid with a small quantity of hot 90 per cent alcohol, pour through filter holding the rest of truxillic acid. Titrate with N/10 alcoholic potash. The figure obtained gives the amount of truxillic acid and from this the amount of truxillin can be determined. Factor for cocain 2.48. Factor for truxillin 2.22. Another procedure is as follows: Subject the crude alkaloids at once to alkaline hydrolysis. Evaporate the alcohol but not to dryness. Bring the products of hydrolysis into solution in water, acidulate and shake out with ether. Evaporate ether at a low temperature and treat the residue with water at 14°, diluting to 1 : 500. Filter and wash, leaving behind the truxillic acid, as before mentioned. Shake out the filtrate and washings with ether. Separate the ether, add a known volume of standard alkali, shake out and finally titrate the excess of alkali with standard sulphuric acid. This figure obtained repre- sents both the benzoic and cinnamic acids. Now add to the solution a slight excess of standard sulphuric acid. Add to this an excess of stand- ard bromine solution. (Bromine in potassium bromide.) Allow to stand with occasional agitation. Finally add potassium iodid solution, which removes the excess of bromine, and titrate the liberated iodine with stand- ard sodium thiosulphate. From the figures obtained the cinnamic acid present can be calculated and by referring to the titration figures obtained ALKALOIDS DERIVED FROM PYRROLIDIN 135 with the mixed cinnamic and benzoic acids the amount of the latter may be determined. The truxillic acid left on the filter may be determined as in the pre- vious method. Factor for cinnamyl cocain 2.22. Cocain is so easily removed by ether or petroleum ether from a solu- tion made alkaline with ammonia that a determination of this alkaloid in products where it occurs as the salt is attended with little difficulty. The chief concern is to be sure that it is separated from the other alkaloids which may be present, and secondly, that in the process of manipulation no decomposition occurs. Atropin and quinin follow cocain closely in solubility and in making a determination of cocain in their presence resort must be had to other than solubility methods. In presence of quinin, cocain may be determined by heating both alkaloids under pressure in the presence of a dilute mineral acid at the temperature of the steam-bath for four hours at least. The benzoic acid resulting from the hydrolysis of the cocain can then be removed by ether and determined by titration. From the results obtained the amount of cocain may be calculated. If it is desired to determine both alkaloids, the residue given by the ether extract from ammoniacal solution should be weighed after drying. Then the mixed alkaloids may be subjected to the acid treatment above mentioned and the cocain determined from the benzoic acid. The difference will be the amount of quinin. • In order to determine the amount of cocain in pharmaceutical prepa- rations, caution must be observed in order that the alkaloid does not become decomposed during the manipulation. If the product is a liquid a weighed or measured quantity should be taken. If alcohol is present evaporate (in neutral solution if possible) until it is driven off. Then dilute the solution, render slightly acid with dilute sulphuric acid 2 per cent and filter if necessary into a separators funnel. Now shake out once or twice with ether, and if caffein is present make four extractions with chloroform. Then add ammonia until the solution is alkaline and shake out three times with petroleum or sulphuric ether. Combine the ether extracts, wash once with distilled water, and then filter the ether solution into a tared dish, carefully washing the filter paper and funnel. Dry at a low temperature and weigh. Then titrate the residue "with N/50 standard acid and alkali. If the residue is a mixture of coca alkaloids and it is desired to specif} r the actual amount of cocain the residue after weighing above should be treated according to Garsed's method. If the analyst is working with pills or tablets, these products should be carefully ground, and a weighed portion throughly extracted with 136 ALKALOIDAL DRUGS alcohol. The alcoholic solution is then evaporated and the residue taken up with dilute sulphuric acid, filtered if necessary, into a separatory funnel and the above procedure followed. When working with an ointment or other product containing grease, place a weighed amount in an Erlenmeyer flask and add ether. Add water and sufficient ammonia to render the solution alkaline. Rotate the flask for fifteen or twenty minutes and then transfer the mixture to a separatory funnel, using caution to prevent any loss. Run off the aque- ous solution into another separatory funnel and shake it out twice more with ether. Combine all the ether extracts, shake out three times with 2 per cent sulphuric acid, collecting acid washings in a fresh separatory funnel. Make alkaline with ammonia, shake out three times with petro- leum or sulphuric ether, filter into tared dish and weigh. COCA LEAF A systematic examination of the coca leaf has shown the presence of a small quantity of material volatile with steam to which the odor and flavor are partly due; from 2-5 per cent of wax; a little saponifiable fat; chlorophyll, from 5-10 per cent of a complex resin which contains a sub- stance contributing to the odor of the drug; from 8-15 per cent of a tannin- like substance; an appreciable quantity of ecgonin; the salts of a phos- phorus acid and unidentified organic acids amounting to about 10-20 per cent; complex carbohydrate-like substances; 8-10 per cent of proteins, cellulose, and allied substances. The nitrogenous material in coca leaf is quite considerable, and a por- tion of it only is represented by the alkaloids and ecgonin. The volatile material contains a little methyl salicylate. The tannin-like substance appears to be characteristic of coca. It is difficult to obtain in a pure and unaltered condition, owing to its sus- ceptibility to the action of reagents and heat. When first obtained it is readily soluble in alcohol and water, but it is easily converted to a form analogous to ellagic acid, which is insoluble in water. Its properties have been described, but as some authors have tested the soluble and others the insoluble form, the literature is confusing. Up to the present time the most important communication on cocatannic acid was made by C. J. H. Warden, 1 who worked with Indian-grown leaves. He describes a yel- low amorphous body, almost insoluble in water, which he claims has the formula C17H22O10. Investigation has since shown that the substance described was an anhydride or some transformation product of the tannin, and that probably it contained a small quantity of the tannin, which was the portion that Warden found soluble in water. 1 Pharm. Journ. and Trans., 3d series, 1887-8, 985. ALKALOIDS DERIVED FROM PYRROLIDIX 137 The separation of the tannin-like substance presents some difficulty, owing to the fact that it is readily decomposed or polymerized on heating and in contact with acids, and furthermore it is very hygroscopic. It can be partially removed from an acid aqueous liquid by means of ethyl acetate, and it is best removed from the leaves by first making a thorough extraction with anhydrous ether to dissolve coloring matter, fats, and waxes, and then percolating with 95 per cent alcohol. The alcohol dis- solves the tannin and resinous constituents, and on concentrating, render- ing anhydrous with sodium sulphate and precipitating by pouring into a large volume of chloroform, the tannin is obtained as a yellowish-brown precipitate, which can be filtered off and dried in vacuo over sulphuric acid. As first obtained, this yellowish substance will be completely soluble in water, but on standing the insoluble form gradually develops. An aqueous solution gives a deep olive-green color with ferric chloride, and the same color and an olive-green precipitate with ferric acetate. It gives a yellow precipitate with bromin water, and a white precipitate with silver nitrate, the latter turning gray on standing, leaving the supernat- ant liquid colorless. With gelatin no precipitate is obtained, even in the presence of sodium chloride, but on adding sulphuric acid in the presence of gelatin a white precipitate is thrown out. Cinchonin sulphate produces a slight but definite precipitate. Potassium ferricyanide and ammonia give a deep brownish-yellow color with a reddish cast. Lead acetate gives an orange or reddish-yellow precipitate. Lime water produces a yellow color, but no precipitate. Xo observable reaction is obtained with starch, antipyrin, barium chloride, magnesia mixture, ammonium molybdate, alum, or borax. Reduction occurs with permanganate and to a slight extent with Fehling's solution. Attempts to determine the character of the tannin have as yet yielded no information on which definite conclusions can be based. SYNTHETIC ANESTHETICS The advance of synthetic chemistry has resulted in the evolution of a number of artificial anesthetics, some of winch have assumed consider- able importance, and as they are often substituted for cocain they will be considered at this point. Most of these substances have well-defined characteristics, they are offered in the pure state or in mixtures from which the}' can be removed by simple means, so that then identification should present no difficult}', and it is not likely that the analyst will encounter more than one individual at a time. Beta eucam, holocain, eupthalmin, novocain, the orthoforms, stovain, cliloretone, acoin, alypin, and anesthesin are being employed to a con- siderable extent. 138 ALKALOIDAL DRUGS Most of them are basic in character, dissolving readily in acids and removable from alkaline solutions by immiscible solvents. These anesthetics fall into several different groups, the members of each group resembling each other to a greater or less extent. Thus the eucains and eupthalmin are derivatives of gamma-oxymethyl piperidin; holocain and acoin may be considered derivatives of anilin antipyretics; the orthoforms, anesthesin and subcutin, are derivatives of benzoic acid; the derivatives of glycocollamido carbonic acid are repre- sented by nirvanin; the derivatives of guaicol include brenzcain, guai- sanol, and guaiacyl; alypin, novocain, and stovain from a fairly well- defined group; and chloretone is trichlor tertiary butyl alcohol. THE EUCAINS Alpha Eucain The hydrochloride of benzoyl-n-methyl-tetramethyl-gammaoxy-piperi- dinecarboxylicmethyl ester. It has almost entirely been displaced by beta eucain. The free base is precipitated from its aqueous solutions by ammonia, alkali, and alkali carbonates; it forms a pasty mass which quickly becomes crystalline. If 5 mils of a 1 per cent solution of alpha eucain is treated with 3 drops 5 per cent chromic acid a beautiful yellow precipitate appears immedi- ately. If 5 mils of a 1 per cent solution is treated with 30 mils 10 per cent potassium iodid solution, a milkiness appears and after a short time color- less plates of eucain hydrogeniodid form and separate. Neither of these two reactions is given by cocain. Beta Eucain C 5 H 7 N(CH3)3(C6H 5 COO)HCl The hydrochloride of benzoyl-vinyl-diaceton-alkamin, or 2, 6, 6-trime- thyl-4-benzoyl-piperidin. The salt forms a crystalline powder soluble 1-25 in water at 15° C, more soluble in warm water. It melts at 268° C. The free base is precipitated by ammonia, alkalies, and alkali carbon- ates, and is liquid at the ordinary room temperature A solution of the salt gives precipitates with Mayer's reagent, iodin in potassium iodide, phosphomolybdic acid, phosphotungstic acid, potas- sium chromate, potassium bismuth iodide and picric acid. No precipi- tate occurs with mercuric chloride unless the solution is concentrated, and the precipitate is soluble in excess of the reagent. With chromic acid a precipitate is given in concentrated solution, it is amorphous and soon agglomerates and dissolves in strong hydrochloric acid. When a ALKALOIDS DERIVED FROM PYRROLIDIN 139 1 per cent solution is treated with chlorine water a dense white turbidity occurs, differing from cocain which gives no precipitate. A crystalline precipitate is thrown down by platinic chloride, which has a characteristic form under the microscope. The precipitate with gold chloride is amorphous. When its acid solution is treated with ammonia a white precipitate is formed which is readily soluble in petroleum ether. Parsons 1 has studied the reactions of the eucains with special refer- ence to distinguishing them from cocain. Potassium iodide (1 : 10) gives, in even moderately dilute solutions of a-eucam hydrochloride, a white silky and glistening precipitate. This precipitate has much the same appearance as the one obtained when stan- nous chloride is added to a cold dilute solution of mercuric chlorid. /3-eucain and cocain give no reaction. " Ammonia, even in dilute solution, precipitates the bases a- or /3- eucain or cocain, but a-eucain is almost insoluble in excess. In 1 per cent solution the white precipitate is at once thrown down, and in the case of /3-eucain or cocain dissolves immediately on addition of about their own volume of strong ammonia, a-eucain, so precipitated, can be diluted at least ten times with strong ammonia without solution. In stronger solutions the difference still exists, but is not so easily recognized. A 3 per cent solution of /3-eucain or cocain requires about five times its own volume of ammonia to be dissolved, and stronger solutions much in pro- portion to the per cent present. In other words, a strong solution of ammonia will dissolve about \ of 1 per cent of the bases /3-eucain or cocain, while it will dissolve but a very small fraction of a per cent of a-eucain. In dilute solutions this is a very characteristic reaction for a-eucain and strong solutions are, of course, very easily rendered dilute for the test. Potassium dichromate, in strong solution, added drop by drop to a 0.5 per cent solution of a-eucain, begins to throw down a fine lemon- yellow precipitate after addition of 1 or 2 drops. The precipitate is then much increased by 1 or 2 drops of strong hydrochloric acid, and is then quite soluble, dissolving only after several times diluting the volume of the solution. With stronger solutions the precipitation takes place at once, the first drop giving a more and more permanent precipitate as the solution grows stronger. The precipitate is notably insoluble in either water or hydrochloric acid. More dilute solutions will show no precipi- tate or only after addition of hydrochloric acid. Cocain, 1 per cent, solu- tion, is not precipitated by potassium dichromate, but the addition of 1 or 2 drops of concentrated hydrochloric acid throws down a yellow pre- cipitate easily soluble in very slight excess of hydrochloric acid on dilu- 1 American Journal of Pharmacy, 1902, p. 198, Jour. Amer. Chem. Soc, 1907, p. 885. 140 ALKALOIDAL DRUGS tion of the solution with water. Weaker solutions do not precipitate, while stronger solutions precipitate at once. The precipitate, however, is easily soluble as before. /3-eucain acts like cocain. The precipitate in all cases is lemon-yellow. The a-eucain precipitate is quite crystalline. All three may throw down a small amount of a yellow colloidal precipitate which sticks to the side of the test-tube and dissolves but slowly, although this in nowise interferes with the test, and does not take place if reagents are added slowly. While this test depends upon the very much greater insolubility of the a-eucain salt, the non-precipitation in dilute solutions of a certain strength until after the addition of hydrochloric acid is quite characteristic for all. The correct strength is about 0.5 per cent solu- tion of a-eucain and about 1 per cent for /3-eucain and cocain. In the case of cocain and /3-eucain, the test may be conveniently applied by pre- cipitating a stronger solution than 1 per cent with potassium dichromate solution, diluting carefully with water until precipitate just dissolves. On addition of a drop of concentrated hydrochloric acid the precipitate will at once reform. This cannot be done with a-eucain, for precipitate once formed it is difficult to get it to dissolve at all. Chromic acid (1 : 20) acts similarly to the dichromate. If a small amount of cocain hydrochloride be rubbed up with dry mer- curous chloride (calomel) and then moistened with alcohol, it rapidly turns to a grayish black, a-eucain hydrochloride becomes slowly a dark gray. 0-eucain hydrochloride is not affected. Platinic chloride throws down slowly a yellow crystalline precipitate from a 1 per cent solution of cocain hydrochloride, which is insoluble in hydrochloric acid, a- and /3-eucain hydrochloride in 1 per cent solution are not altered. In stronger solutions all three hydrochlorides are immedi- ately precipitated by platinic chloride, but the cocain precipitate is not soluble in hydrochloric acid, while the precipitates by either eucain are at once dissolved. Cocain solutions almost always cause mydriasis; /3-eucain does not dilate the pupil. The lactate of /3-eucain is a white non-hygroscopic powder melting at 152-155° C. and readily soluble in water and alcohol. The base is pre- cipitated by ammonia and alkalies and responds to the usual character- istic reactions. If 1 gram of /5-eucain lactate is warmed with a few drops of dilute sul- phuric acid and 1 mil of potassium bichromate (1 : 10) the odor of acetalde- hyde is evolved. Eupthalmin Hydrochloride The hydrochloride cf phenyl-glycolyl-n-Methyl-beta-viny!-diaceton» alkamin. ALKALOIDS DERIVED FROM PYRROLIDIN 141 It is the mandelic acid derivative of beta eucain, and possesses marked mydriatic properties. It is not an anesthetic. The salt forms a colorless crystalline powder. Its solution gives pre- cipitates with Mayer's reagent and with iodine in potassium iodide, phos- phomolybdic and phosphotungstic acids. No precipitate occurs with potassium chromate, nor with platinic chloride or chlorine water. When evaporated with nitric acid a yellow residue is left which on treatment with alcoholic potash gives off an odor of benzaldehyde and red oily drops appear. On treating with a solution of molybdic acid in sulphuric acid no color appears at first, but on standing the outer rim becomes blue. Holocain Hydrochloride Holocain. Para-diethoxy-ethenyl-diphenylamidin. CH3C- (NC 6 H40C2H5)NHC 6 H40C2H5 The base is a condensation product of para-phenetidin and acetphen- etidin and forms white crystals melting 121°; insoluble in water. The hydrochloride is soluble in water and alcohol. An acid solution of holocain gives a white precipitate with ammonia which is slightly soluble in petroleum ether but readily soluble in ether. Precipitates are produced by the ordinary alkaloidal reagents. An aqueous solution acidified with hydrochloric acid gives a white precipitate and with mercuric chloride, and with calcium hypochlorite a violet pre- cipitate is obtained, soluble in ether, and imparting to it a red color. When evaporated with nitric acid the base leaves a yellow residue which turns red on the addition of alcoholic potash and gives off a dis- agreeable odor. Acoin Di-para-anisyl-monophenetyl-guanidin-hydrochloride. (CH 3 OC6H 4 NH)2CNCoH 4 OC2H5 +HC1 Acoin is a white crystalline powder — melting-point 176°, soluble in water. Its solutions are precipitated by the ordinary alkaloidal reagents and with bromine water a dirty-yellow curdy precipitate forms which turns to purple on adding ammonia dissolved in chloroform. Immediate reduction takes place with permanganate. The base is somewhat soluble in petroleum ether, and readily soluble in ether. It gives a deep red color with nitric acid and on treating the evaporated product with alcoholic potash an agreeable odor is given off. 142 ALKALOIDAL DRUGS - The Orthoforms Orthoform. — Para-amido-meta-oxybenzoic-methyl-ester. C 6 H3(COOCH3)NH 2 OH 1-4-3 It is a white, odorless, tasteless, crystalline powder; slightly soluble in water, readily soluble in alcohol, and melting 118-120° C. Its solution in acetic acid gives a green color with PbCb. Orthoform " New ".— Meta-amido-para-oxybenzoic-methyl-ester, C 6 H3(COOCH3)NH 2 OH, 1-3-4. Fine white powder, difficultly soluble in water, readily soluble in 5 to 6 parts of alcohol, soluble in ether 1-50, and alkalies. It occurs in two modifications, sometimes crystallizing out of chloro- form in quadratic plates melting at 110-112° C. As a general thing, how- ever, it crystallizes in shining needles melting at 142°. The lower melt- ing modification is transformed to the higher on fusion. Its solutions are neutral. A cold aqueous solution is colored red by ferric chloride, and on heating the red is changed to green. On boiling the aqueous solution, orthoform is decomposed into methyl alcohol and paraoxybenzoic acid. If 0.1 gram is dissolved in 2 mils of water with help of a little dilute sulphuric acid, and a few drops of sodium nitrite solution added, the solu- tion becomes yellowish red and a yellow precipitate comes down which becomes intensely red in contact with the air. With concentrated nitric acid a blue color changing to red occurs. No odor develops on the subsequent addition of alcoholic potash. The other orthoform gives a green color with nitric acid. It gives precipitates with phospho-molybdic and phosphotungstic acids. With bromine water a yellowish green precipitate is obtained differing from most of the other synthetic anesthetics which give a white or a yellowish precipitate. On subsequently adding ammonia the green pre- cipitate gives way to a dark-red solution. It does not give precipitates with either Mayer's or Wagner's reagents. It is practically insoluble in petroleum ether, very slightly soluble in chloroform, more readily in ether. The Orthoforms combine with chloral to form tasteless products of great hypnotic action. They are difficultly soluble in water but readily so in alcohol and ether and on warming with mineral acids are broken up, chloral being liberated. ALKALOIDS DERIVED FROM PYRROLIDIN 143 Anaesthesin Ethyl ester of paramido benzoic acid. C6H4NH2COOC2H5 It forms a white odorless, tasteless powder, melting 89-91° C. It is sparingly soluble in cold water, readily soluble in hot water and in organic solvents, except petroleum ether, in which it dissolves but sparingly. It dissolves readily in fixed oils and fats. It is removed by solvents from acid solution. 0.1 gram anesthesin treated with 100 mils of water and a little hydro- chloric acid followed by a few drops of sodium nitrite solution and an equal quantity of beta-naphthol solution results in the production of an intense cherry red color changing to orange with acids. On boiling with alkalies it is decomposed into paramido-benzoic acid and ethyl alcohol. It gives precipitates with the ordinary alkaloidal reagents, except Mayer's reagent and tannic acid. No precipitate is given with potassium chromate until the solution is acidified, when a brown deposit takes place with reduction. Immediate reduction occurs with potassium perman- ganate. A dark greenish-black residue is left on evaporation with nitric acid and no odor is given off with alcoholic potash. Propaesin Propylester of paramido benzoic acid. CGH4NH2COOC3H7 This substance occurs as a white bulky crystalline powder, neutral to litmus and having a melting temperature 74-76°. It is slightly soluble in water, and with difficulty in dilute sulphuric acid, unless the liquid is warmed, but it is readily soluble in alcohol, chloroform, and ether. An acid solution of propaesin does not give a precipitate with Mayer's reagent but other usual alkaloidal reagents, Wagner's, phosphomolybdic acid, phosphotungstic acid give immediate precipitates. With potassium chromate no reaction occurs, but after adding an equal volume of con- centrated hydrochloric acid, the mixture darkens and a dirty brown pre- cipitate comes out. The same reaction occurs in the case of 5 per cent chromic acid and hydrochloric acid. Potassium permanganate, when in dilute solution, is at first decolorized when added to an acid solution of propaesin; but as soon as an excess is present the permanganate is reduced. Bromin water gives a white precipitate and no change occurs when ammonia is subsequently added. An aqueous solution of its hydrochlo- ride gives precipitates with platinic chloride and with palladium chloride. 144 ALKALOIDAL DRUGS No characteristic color reactions occur with oxidizing agents, nor with mineral acids. Ammonium vanadate gives a purple color soon chang- ing to brown and gradually fading into gray, the best results apparently occurring when the propaesin is in considerable excess. When treated with nitric acid and evaporated over the steam-bath, the residue gives no characteristic odor when alcoholic potash is added. Propaesin is removed from its acid solutions by ether and by chloro- form, and from its alkaline solutions petroleum ether will separate it readily, though this solvent removes it but slightly from acid solutions. When heated with a solution of potassium hydroxide it melts and forms an oily layer. If this mixture is boiled, propyl alcohol is evolved which may be recognized by its odor, and the alkaline liquid will contain par- amido benzoic acid. The latter may be separated by neutralizing with mineral acid. Subcutin Para-phenolsulphonic acid-ethyl ester of para-amidobenzoic acid. CeH^COOCs^NHsSOsHCeHiOH The paraphenol sulphonic acid derivative of anesthesin. It is a white crystalline powder melting-point 195.6°. This product is not readily soluble in cold water, but on warming the liquid it dissolves readily, the odor of ethyl benzoate being very marked. The aqueous solu- tion obtained either in the cold or on warming is acid to litmus. It is readily soluble in ether, but does not dissolve to any great extent in chloro- form and petroleum. It is completely removed from a solution acidulated with sulphuric acid by ether and partly by petroleum ether. From ammoniacal solu- tions it is much less readily given up to solvents. An acid solution gives no precipitate with Mayer's reagent, but it reacts at once with iodine solution, the precipitate soon separating out in oily drops. Precipitates are given by picric acid, palladium chloride, phosphotungstic and phosphomolybdic acids and bromin water. Tan- nic acid gives no precipitate. Chromic acid solution produces a turbidity which is not changed on the addition of hydrochloric acid, and on standing a brown precipitate gradually settles. Potassium chromate gives no pre- cipitate but on adding hydrochloric acid a deep red to brown color appears and a brown precipitate is found. Immediate reduction occurs with potas- sium permanganate. Ferric chloride solution in small amount produces a brownish purple but the color changes to a yellowish on adding more of the reagent. This reaction is not given by anesthesin. Formaldehyde sulphuric acid acting directly on subcutin gives no color at first, but a salmon shade soon develops, which gradually darkens to red then becomes ALKALOIDS DERIVED FROM PYRROLIDIN 145 brownish red and finally brown. Ammonium vanadate produces immedi- ately a beautiful green changing at once to blue and disappearing in a moment. Neither of these reactions is given by anesthesia. With sul- phuric acid and bichromate a green color appears at once. On evapor- rating to dryness with nitric acid a brownish-yellow residue is left. Alco- holic potash becomes blood red when added to this product and an agree- able odor differing somewhat from ethyl-benzoate is given off. Cycloform. Isobutyl paramidobenzoate C 6 H4(NH2)COOCH 2 CH(CH3)CH3 Cycloform is a white crystalline substance, melting 65°, slightly soluble in water, but dissolving readily in alcohol, ether, and benzol. When heated with concentrated sodium hydroxide it evolves isobutyl alcohol, recog- nized by its odor. Nirvanin The hydrochloride of diethyl glycocoll-p-amido-o-oxybenzoic acid- methyl ester. HC1(C 2 H 5 )2N CH 2 CONHC 6 H3(OH)COOCH3 It forms white prisms melting at 185° C, soluble in water and alcohol. The base is precipitated by sodium hydrate or ammonia as a white solid, soluble, in excess, but in the case of ammonia a precipitate reappears on warming. Its solution gives precipitates with all the ordinary alkaloidal reagents, and a violet color with ferric chloride. On evaporating with nitric acid a red-colored residue is left which gives no characteristic odor on the addition of alcoholic potash. Alypin The hydrochloride of benzoyl-tetramethyl-diamino-ethyl isopropyl alcohol. (CH3)2NCH2C(C2H 5 ) (C 6 H 5 00) (CH 2 N(CH 3 ) 2 )HC1 Alypin is a white crystalline powder melting 169°. It forms a neutral solution in water which is not rendered turbid by sodium bicarbonate. Its solutions give precipitates with Mayer's and Wagner's reagents, with phosphomolybdic and phosphotungstic acids and with bromin water, but no precipitate occurs with potassium chromate. Potassium bichromate produces a yellow crystalline precipitate soluble in hydrochloric acid. Potassium permanganate produces a violet crystalline precipitate which turns brown on standing. 146 ALKALOIDAL DRUGS On the addition of alcoholic potash to a residue obtained by the evapo- ration of alypin with nitric acid, a disagreeable odor is given off. The free base is a colorless, strongly alkaline oil which is somewhat solu- ble in water. When warmed with sulphuric acid at the temperature of the water- bath, and then diluted with a little water, the odor of ethyl benzoate is evolved. Stovain Ethyl-dimethyl-amino-pentanol-benzoyl-hydrochloride. C 6 H5COO(CH3)CC2H5CH2N(CH3) 2 HCl Stovain forms small glassy plates, melting 175° C, soluble in water, alcohol, and acetic ether, but almost insoluble in ether. The free base is precipitated by alkalies, and may be removed from solution by immiscible solvents, petroleum ether dissolving it readily. It is not precipitated by potassium iodide, but is thrown down by all the other alkaloidal reagents. It is precipitated by sodium bicarbonate and in this respect and in its action with potassium iodide it differs from alypin. The residue obtained on evaporation with nitric acid gives off an odor of ethyl benzoate and isonitrile when treated with alcoholic potash. 0.1 gram of stovain treated with 5 mils sulphuric acid and heated for five minutes at 100° C. gives off the odor of ethyl benzoate on adding 5 mils water. Novocain The hydrochloride of para-amino-benzoyl-diethyl-amino ethanol. C 6 H4NH2(l)COOC2H4N(C2H 5 )2(4)HCl The hydrochloride is a crystalline salt soluble in water 1-1 and in alcohol 1-30. Melting-point 150-155°. Caustic alkalies and alkali carbonates precipitate the base as an oily mass which crystallizes w T hen cool. Sodium bicarbonate does not pre- cipitate the base. From ether the base crystallizes in the anhydrous state, melting at 58-60°, while from alcohol it crystallizes with 2H2O, melt- ing at 51°. It gives precipitates with alkaloidai reagenxs and is soluble in sulphuric and hydrochloric acids without color. 0.1 gram of novocain in 5 mils water treated with 2 drops hydro- chloric acid and 2 drops sodium nitrite solution, gives a scarlet red pre- cipitate when added to a solution of beta naphthol. On evaporating with nitric acid a yellowish red residue is left which ALKALOIDS DERIVED FROM PYRROLIDIN 147 on treatment with alcoholic potash becomes red and gives off the odor of isonitrile. Potassium chromate gives no precipitate. On adding hydrochloric acid reduction to a green color occurs which becomes red on standing. Novocain when mixed with mercurous chloride and moistened with alcohol turns dark similarly to cocain. If 0.5 gram of novocain in 2 mils water be treated with potassium bichromate solution drop by drop a precipitate is formed which dissolves on shaking. Chloretone Trichlor-tertiary-butyl-alcohol. (CH3) 2 C0HCC1 3 Chloretone occurs in snow-white crystals having a camphoraceous odor and taste. It is volatile with steam. It is soluble in chloroform, acetone, alcohol, ether, petroleum ether, glacial acetic acid, glycerin, fixed and volatile oils, also in warm water to the extent of 1 per cent, but on cool- ing a portion crystallizes out, the cold saturated solution containing 0.8 per cent. It possesses a peculiar property of sliding and rotating about on the surface of water. When applied to the tongue it causes first a slight peppery sensation, and then a numbness, the latter, however, being much less pronounced than that caused by cocain and unaccompanied by the slippery feeling. Chloretone of the formula (CHs)2COHCCl3 has a melting-point of 97° C. It forms solid solutions with water, these products having melting- points down to 75°, depending on the amount of water present, and it is in some of these latter forms that it occurs on the market. Its solution in acid does not give precipitates with the ordinary alka- loidal reagents. It is soluble with decomposition in strong sulphuric acid. With cold dilute potassium hydrate solution alpha-chlorisobutyric acid results and with concentrated potash, acetone, chloroform, and methyl acrylic acid. It is soluble in dilute ammonia, from which solution it may be removed by means of immiscible solvents. Deniges 1 describes the following qualitative reactions for chloretone and also gives a method for its quantitative determination: If 5 mils of a 5 per cent alcoholic solution of chloretone be boiled with 1-2 mils of solution of sodium hydroxide and allowed to cool, the clear solution produced becomes turbid on addition of mercuric sulphate; or, if instead of mercuric sulphate a few drops of fresh sodium nitro- J Rep. de Pharm., 1905, No. 11. 148 ALKALOIDAL DRUGS prusside are added, followed by acetic acid in slight excess, the well-known carmine color of Legal's acetone reaction is developed. Ammoniacal silver nitrate is decomposed by solution of chloretone in the cold; Fehling's solution is reduced by it on boiling. The quantitative determination by titration is effected by adding to 10 mils of a 1 per cent solution of chlore- tone, in diluted alcohol, 1-2 mils of solution of sodium hydroxide, free from chlorine, and 10 mils of alcohol, and heating the mixture to boiling. After cooling, 1-2 mils of nitric acid (1.39) are added, the liquid is adjusted with water to 100 mils and the sodium chloride formed is titrated in the usual manner with silver nitrate, using potassium chromate as indicator and calcium carbonate to render the liquid milky. One mol. of chlore- tone forms 3 mols. of sodium chloride. Chloretone should always be looked for in remedies designed to relieve seasickness. Guaiasanol. " Gujasanol " Diethylglycocoll guaiacol hydrochloride. C 6 H4(OCH3)OCOCH 2 N(C2H5)2HCl Gujasanol forms white prismatic crystals, melting 183-184° C, readily soluble in water, and the odor of guaiacol is apparent. Mayer's reagent gives a yellowish white precipitate and Wagner's throws out a brown precipitate which soon becomes oily and sticks to the sides of the container. It gives a white precipitate with ammonia which is readily soluble in petroleum ether and remains a colorless oily liquid on evaporating the solvent. Brenzcain Guaiacol benzyl ester. Pyrocatechin methyl benzyl ester. C6H4OCH3OCH2C6H5 Brenzcain forms colorless crystals melting 62°, spluble in alcohol, ether, and oils, but insoluble in water. On warming with hydrochloric acid guaiacol results and with potassium permanganate and sulphuric acid benzaldehyde is formed. Guaiacyl Calcium ortho guaiacol sulphonate. (C 6 H3(OH)(OCH 3 )S03)2Ca Gaiacyl is a grayish-brown powder readily soluble in water and alcohol. Its aqueous solution is violet red. CHAPTER VI ALKALOIDS DERIVED FROM QUINOLIN THE CINCHONA ALKALOIDS AND THEIR DERIVATIVES Cinchona bark and certain of the alkaloids contained therein, have an extended and important use in medicine. The drug itself, depending on the variety, may contain a number of different bases, and while the list is extensive numerically, the actual number with which the drug analyst will be concerned is small, being limited, except in rare instances, to four or perhaps five individuals, quinin, quinidin, cinchonin, cinchoni- din, and cuprein. Pictet mentions twenty-one alkaloids in his list; Chick, in the new edition of Allen, gives thirty-one and later mentions homo- quinin, which is described by Pictet in his original list, so the number may be left at thirty-two. Pictet divides the bases into six main groups accord- ing to their composition and according to the nature of the decomposition products which are produced by the action of mineral acids. Each of the first three groups contains a subgroup which differs from the main group only in possessing a slightly greater amount of hydrogen. Chick classi- fies the alkaloids in five groups as follows: 1. Cinchonin Class. Paricin, Ci 6 HisON2 Cinchotin or Hydrocinchonin Cinchamidin or Hydrocinchonidin > C19H24ON2 . Cinchonamin Cinchonin Cinchonidin Homocinchonidin Cinchonicin Paytin Paytamin 2. Quinamin Class. C19H22ON2 C 2 iH 2 40N 2 Quinamin . M ^ . . \ C19H24O2JN2 Conqumamm Javanin Cuprein, C19H22O2N2 149 C22H2604N2 150 ALKALOIDAL DRUGS 3. Quinin Class. Hydroquiiiin I r „ n M Quinin Quinidin > C20H24N2O2 Quinicin J 4. Cusconin Class. Chairamin Conchairamin Chairamidin Conchairamidin Concusconin Aricin Cusconin Cusconidin 5. Anhydro bases. Dicinchonicin Diquinicin Homoquinin In addition to these bases there have been reported a number of acid and neutral bodies including quinic, quinovic, caffeic, oxalic, and certain tannic acids, quinovine, quinia red, quinovic red, cinchocerotine, cinchol, cupreol, cholesterol, etc. CINCHONA BARKS The drugs containing these alkaloids are obtained from several trees belonging to the genera Cinchona and Remijia (family of the Rubiaceae). Many species of Cinchona have been described, but those yielding bark of any practical importance are limited. Of the varieties of commercial importance may be mentioned pale, crown or loxa bark from Cinchona officinalis; yellow Peruvian or Calisaya bark from C. calisaya and hybrids; red bark from C. rubra and C. succirubra and its hybrids, and containing a high percentage of cinchonidin; pitayo bark from C. Patayensis; Colum- bian or Carthagina bark from C. lanceolata, C. lancifolia, C. cordifolia, etc.; Ledger bark from C. Ledgeriana, very rich in quinin; and cuprea bark from Remijia pedunculata. The value of a bark depends on its alka- loidal content and this is extremely variable, barks having as high a con- tent as 15 per cent have been reported and from tins it runs down to a fraction of a per cent. Under the present system of cultivation the trees are not destroyed when the bark is gathered, a part only is removed, the remainder being left intact and the stem is then covered with moss under ch new bark forms rapidly. Quinin, cinchonin, and cinchonidin are ALKALOIDS DERIVED FROM QUINOLIN 151 the bases most frequently found, quinidin is less common and is never in large amount Cinchona and its alkaloids probably enter into a greater number of combinations and have a wider field of application than any other drugs used in medicine. Their properties are tonic, febrifugal, and antiperiodic, and hence they are recommended in malarial troubles and in convalescence. The classes of pharmaceuticals containing them include a great variety of pills, tablets, elixirs, wines, syrups, capsules, and bitters. First taking up cinchona extract we find that this product is used in a plain elixir of calisaya; in combination with bismuth and ammonium citrate, with pyrophosphate, with strychnin and pepsin, either altogether or with one or more; with beef extract and iron oxy chloride in the beef, iron, and wine products ; with malt extract ; and in various alcoholic prod- ucts known as bitters such as Dubonnet, Quinquina, Ferro China Bisleri, and Quinin whisky types. Quinin sulphate occurs in pill and tablet formula? and in elixirs and bitter tonics combined with iron pyrophosphate and strychnin sulphate. Among the pills and tablets may be mentioned combinations of quinin sulphate with strychnin, reduced iron, and arsenous acid used in malarial conditions in which will be found at times aloes, Podophyllum resin and Gelsemium extract; iron and quinin citrate; iron, quinin, and strychnin citrate; quinin sulphate, arsenous acid, strychnin, aconite, and morphin for neuralgia; phosphorus, iron, either reduced or as ferrous carbonate, and quinin, with and without strychnin and sometimes with Digitalis and ipecac; quinin, arsenous acid, gentian, and atropin sulphate; quinin sulphate and Capsicum or oleoresin black pepper; iron, quinin, and zinc valerianates, sometimes with gold and sodium chloride and sumbul root; Warburg tincture containing quinin sulphate, rhubarb, angelica seed, elecampane, saffron, fennel, gentian, zedoary root, cubeb, myrrh, white agaric, camphor, with or without aloes; bronchitis tablets of belladonna, ipecac, opium and quinin sulphate; coryza tablets of camphor, quinin, morphin, and atropin sulphate; or of similar composition with ammonium chloride and no atropin; rhinitis tablets of camphor, belladonna, and quinin sulphate; acetanilid and quinin sulphate; acetanilid, caffein, sodium bicarbonate, sodium bromide, and quinin sulphate; ergot, Digitalis, and quinin sulphate; hypophosphites compound containing the hypophos- phites of quinin, calcium, iron, sodium, potassium, manganese, and strych- nin, sometimes with guaiacol; the same bases are also presented as phos- phates; rheumatic tablets composed of quinin sulphate, extracts of Colchicum, colocynth, Hyoscyamus, opium, and mercury; cold tablets com- posed of quinin hydrobromide, aloin, Capsicum, calomel, aconite, ipecac, and opium, sometimes with cascara; inspissated oxgall, pancreatin, colo- cynth, Nux Vomica, Taraxacum and quinin sulphate; and quinin sulphate Ib2 ALKALOIDAL DRUGS or bisulphate alone in tablets and capsules of various strengths. Quinin and urea hydrochlorate are used in hypodermatic tablets. The elixir formulae often include pepsin and bismuth and ammonium citrate and the phosphate syrups will contain the phosphates of the alkaline earth and alkali bases. Quinidin will be found substituted for quinin and it is well to look for the former in all products which especially claim to be free from quinin. Cinchonidin sulphate is combined with iron, arsenic, and strychnin in tablets and sometimes replaces quinin in the other formulas mentioned. It has been sold in an aphrodisiac compound mixed with Coca, phosphorus, Nux Vomica and bromides. It will be found in tonic pills with Xantho- oxylum, dogwood and Capsicum, and is also marketed alone as is also cinchonidin salicylate. Cinchonin sulphate has the same remedial properties as quinin sulphate and may be met with at any time, though its use is much limited compared to quinin. Cinchonin This alkaloid differs from quinin in lacking a methoxyl group, the con- stitutional formula accredited to it at present being . ,\ H2C CH2 CH — CH=CH2 1 1 1 ch 2 — COHCH2CH2 H I \ C C X N- /\ /X HC C CH I II I HC C CH Yh X n/ It is easily crystallized and melts from 250-265°, depending on its purity, and may be distilled unchanged in a current of hydrogen, ammonia, or in vacuo. It is somewhat soluble in boiling water, but almost insoluble in cold water, somewhat soluble in chloroform, benzol, amyl alcohol, and alcohol, and difficultly soluble in ether, especially when the solution and solvent are cold. It is a fairly strong diacid and bitertiary base, and both the alkaloid and its salts are dextrorotatory. Cinchonin yields several isomers when acted upon by different chemical reagents. Among these may be mentioned cinchonidin, its stereoisomer, ALKALOIDS DERIVED FROM QUINOLIN 153 which also occurs naturally, and cinchonicin, obtained by heating the alkaloid with very dilute sulphuric acid to 130° C. The double bond in the side chain facilitates the addition of chlorine and bromine, giving in the cold, addition products. The dichloride and dibromide are crystalline, somewhat unstable, and behave as diacid bases. It also gives monobenzoyl, and monoacetyl derivatives due to the hydro- xyl group. The acid solutions of cinchonin are not fluorescent and the alkaloid does not give the thalleoquin test, thereby differing from quinin; it gives no well-defined characteristic color tests, but is precipitated by all of the ordinary alkaloidal precipitants including Mayer's and Wagner's reagents, phosphomolybdic and phosphotungstic acids, tannin, bromin water, gold chloride, platinic chloride, mercuric chloride, picric acid, potassium bis- muthic iodide, and sodium carbonate; with potassium ferrocyanide it gives a precipitate soluble in excess; it is not precipitated by potassium iodide. It differs from its isomer cinchonidin, by not precipitating with Rochelle salts. Cinchonin picrate melts 193-194° C. Cinchonin forms a well-defined sulphate, containing two molecules of water, which become anhydrous at 100° C. This salt is much more readily soluble in water than is quinin sulphate, the saturated solution being about 2 per cent. The anhydrous salt is soluble in 60 parts of cold and in 22 parts of boiling chloroform which distinguishes it from the sulphates of cinchonidin and quinin. Cinchonin hydrochloride contains two molecules of water and is readily soluble in water and alcohol, and somewhat in ether and chloroform. Cinchonin iodosulphate is used as an antiseptic and is sometimes sold under the name " Antiseptol." Ordinary commercial cinchonin contains considerable hydrocinchonin (cinchotin) often as much as 20 per cent, which renders the salts con- siderably more soluble than if chemically pure. Thus 1 part of pure cin- chonin sulphate is soluble in 72 parts of water at 12° C, while the ordinary commercial salt requires but 64 parts, 1 part of pure hydrocinchonin dis- solves in 37 parts of water. Cinchonin is readily converted into isomeric substances. On heating with acetic acid it gives rise to cinchotoxin, a highly poisonous base. Pure cinchotoxin, when heated, first softens and then melts at 58-59° C. It is readily soluble in alcohol, acetone, chloroform, and benzene. In hot petroleum spirit it is less soluble, and separates on cooling in oily drops, which crystallize after some time. In contact with water it gradually becomes fluid, and a small portion passes into solution. This solution is precipitated and rendered turbid by addition of an excess of alkali. Cinchotoxin yields a series of crystalline salts, and forms a hydrozone 154 ALKALOIDAL DRUGS and several nitroso derivatives. The methyl derivative of cinchotoxin appears to be identical in all respects, chemical and physical — excepting some trifling differences in crystalline form, which require further investi- gation — with methyl-cinchonin. This similarity extends to their respec- tive derivatives. On the other hand, cinchotoxin itself is absolutely indis- tinguishable — again excepting very slight disparities in the form of the respective crystals — from cinchonicin. The study of this compound and its derivatives went a long way to establish the constitution of cinchonin. Cinchonin subjected to the action of sulphuric and hydrochloric acids under various conditions has yielded no less than 10 isomerides of the base, C19H22N2O, namely a and /3-isocinchonin, apoisocinchonin, apocinchonin, isoapocinchonin, diapocinchonin, dicinchonin, homocinchonin, pseudo- cinchonin, and cinchonicin. The experiments described show how easily one base may be converted into another, and that such a change may actually occur during the process of the extraction of a base from the plant, or during the purification. Cinchotenin Cinchotenin is obtained by the oxidation of cinchonin with potassium permanganate with the formation of formic acid. The following equation represents the change: C19H22N2O+O3 = C18H20N2O3+H • COOH The reaction is general for the cinchona alkaloids, and has been investi- gated in the cases of cinchonidin, quinin, and quinidin. • Cinchonidin Cinchonidin, the stereoisomer of cinchonin, accompanies quinin in all the cinchona barks, and in the extraction of the alkaloids it separates chiefly with quinidin. It is especially characteristic of the bark of C. succirubra. It crystallizes from alcohol in prisms melting 202-203°, very sightly soluble in water, somewhat soluble in ether and readily soluble in alcohol, chloroform, and amyl alcohol. Both the alkaloid and its salts are laevorotatory. Cinchonidin gives precipitates with all of the usual alkaloidal reagents and is distinguished from cinchonin by yielding insoluble compounds with potassium iodide and with Rochelle salt. The precipitate obtained with potassium chr ornate is much more soluble than that given with cinchonin. Its acid solution is not fluorescent and it gives no thalleoquin test. The " Herapathite " test described under quinin yields microscopic needles without metallic luster. The picrate darkens at 200° and melts at 208- 209° with decomposition. ALKALOIDS DERIVED FROM QUINOLIN 155 y Cinchonidin forms several well-defined salts, of which the sulphate is probably the one most universally met with in chemical work. The sul- phate crystallizes with varying amounts of water, depending on the con- centration and nature of the solvent; hot concentrated aqueous solutions yield a compound with three molecules of water, this being the salt official in the U. S. Pharmacopoeia. The crystals lose their water when heated to 100° C. The anhydrous sulphate is almost insoluble in absolute chloro- form, being similar to anhydrous quinin sulphate in this respect, and dif- fering markedly from the sulphates of cinchonin and quinidin which go into solution readily. In all of its reactions affecting its structure cinchonidin acts the same as cinchonin, most of their transformation and decomposition products being identical, Cinchotin This alkaloid, also called hydrocinchonin, contains two more hydrogen atoms than cinchonin and is found in crude cinchonin especially from the bark of Remejia purdieana. It may be isolated by treatment with perman- ganate which destroys the cinchonin more rapidly than the cinchotin is oxidized. It is dextrorotatory, melts at 286° (268° Mulliken), sparingly soluble in ether and forms addition products with hydrochloric and hydri- odic acids. It forms a compound with methyl iodide which separates from methyl alcohol in pale yellow crystals melting 234-235°. Cinchamidin This alkaloid, also called hydrocinchonidin, is isomeric with cinchotin, melts at 230°, is lsevorotatorj^ and resembles the latter in its general prop- erties. It dissolves with difficulty in ether and is almost insoluble in chloroform even when hot. Its solutions in dilute mineral acids are fluores- cent. Cinchonamin Cinchonamin, isomeric with cinchotin and cinchamin, is obtained from the bark of Remejia purdieana. It is dextrorotatory and melts 184-185° according to Pictet, though Chick gives 194°. It is readily soluble in the ordinary organic solvents except petroleum ether and is attacked by permanganate. It is seen commercially in the form of yellowish-white crystals and forms well-defined salts of which the nitrate is especially characteristic, being but slightly soluble in water and alcohol, and insolu- ble in dilute nitric acid. The compound is formed by dissolving the base in water containing a small quantity of hydrochloric acid, and adding a few drops of nitric acid. 156 ALKALOIDAL DRUGS Cinchonamin does not give the thalleoquin test. With vanadium sulphuric acid (MandehVs reagent) it gives a bluish-violet color, changing to reddish violet and finally bluish green. With Froehde's reagent it gives a green tint turning yellowish green. Quinin This alkaloid is by far the most important of the cinchona group and is one of the most widely used of remedial agents. The analyst of drug products will frequently be called upon to identify it, to distinguish it from other bases of this group, and to determine it in mixtures with other alkaloids. It is not as easy of identification as strychnin, with which it is often mixed as its color reactions are less positive and those that it does possess are also common to other members of its own immediate family; but it is comparatively stable, and its solutions can be treated with reagents which will break up some of the more delicate alkaloids such as aconitin, atropin, and cocain, and by this means the latter if present may be removed, and quinin subsequently separated and purified. Quinin differs constitutionally from cinchonin and cinchonidin by pos- sessing an — OCH3 group and from our present state of knowledge its formula may be written as follows : H / H2C CH2 CH — CHC=H2 I ! I CH 2 COH CH 2 CH 2 C C X N/ /\ /\ CH3OC C CH I II I HC C CH CH iN Commercial quinin is apt to retain traces of cinchonin, quinidin, hydro- quinin, and cinchonidin. It is laevorotatory while its stereoisomer quinidin is dextro. Quinin alkaloid, when precipitated out of solution, crystallizes as a white flaky or micro-crystalline powder; when obtained by evaporat- ing an ethereal solution, it is a colorless, hard, varnish-like mass, and if in large amount with a crystalline appearance in places. It is odorless and has an intensely bitter taste. When freshly crystallized it contains three molecules of water, two of which are lost on heating to 100° and the third at 125° C. The anhydrous alkaloid melts 171-172° C. while the ALKALOIDS DERIVED FROM QUINOLIN 157 crystalline body with three H 2 fuses at 57°. The anhydrous body is slightly soluble in cold water but somewhat more readily when heated, it is fairly soluble in benzol and glycerin and readily in ether, and alcohol. The dry alkaloid is but slightly soluble in petroleum ether, but when freshly precipitated it is taken up by this solvent to a considerable extent the same as is strychnin. It is very slightly soluble in 20 per cent potassium hydroxide and about as soluble in dilute ammonia as it is in water. Its aqueous solution is alkaline to litmus. Quinin dissolves in sulphuric, acetic, and tartaric acids with a strong bluish fluorescence, discernible at great dilution and destroyed by the halogen acids. Quinidin, hydroquinin, hydroquinidin, and diquinicin give fluorescent solutions but quinamin, cinchonin, cinchonidin, cusconin, cuprein, and quinicin do not. This test will probably be the first indi- cation of the presence of quinin that the analyst will have in working with an unknown mixture, and will be noted early in the systematic scheme of separation. The thalleoquin test is a valuable confirmatory test for quinin. It is a test which is extremely delicate if carefully applied, but unless one is familiar with its vagaries it will often prove disappointing. Of all the well-known tests in alkaloidal chemistry this reaction will cause the analyst more uncertainty than any others. When there is a fair amount of the sample present it ought to be obtained without difficult}^, but if there is only a minute quantity available the result will more than likely be neg- ative. The directions in the Pharmacopoeia are as follows: 1 mil of an aqueous solution of the alkaloid 1-100 containing just sufficient sulphuric acid for solution is treated with 2 mils bromine water and 1 mil dilute ammonia water which will produce a green color. La Wall 1 has recently published a procedure by means of which he claims to be able to detect 1 : 200,000 of quinin by this test. According to the author 100 mils of a solution of the sulphate of the alkaloid to be tested at a dilution of 1 : 100,000 or 1 : 200,000 are poured into a Nessler tube, 5-10 drops of potassium bromate solution (0.5 gram potassium bro- mate, 10 mils hydrobromic acid 10 per cent and 90 mils water) added, the contents well mixed and then treated with 10 drops stronger ammonia water, which will produce a green tint in presence of quinin or other cin- chona alkaloid giving the thalleoquin test. A modification of the thal- leoquin test known as the erythroquin test and valuable as confirmatory evidence, consists in following the bromin water with a few drops of potassium ferro- or ferricyanide, and subsequently with ammonia, when a red coloration is produced instead of the green ; on shaking with chloro- form the coloring matter will dissolve and appears to better advantage especially in very dilute solutions. 1 Amer. J. Pharm., 1912, 84, 484. 158 ALKALOIDAL DRUGS Buchbinder's directions for conducting this test are as follows: Have ready a test-tube (No. 1) containing 1 mil of chloroform and 3 mils of a saturated solution of potassium ferrocyanide. In another test-tube (No. 2) pour 5 drops of bromine water. Working as rapidly as possible, add to test-tube No. 2, 1 or 2 mils of the solution to be tested; immediately pour the contents of test-tube No. 2 into test-tube No. 1 and shake thoroughly. Add a little concentrated ammonia and shake again. A pink to red coloration will appear in the chloroform layer if quinin is present. If a precipitate forms on adding the solution to the bromin water, the test may possibly fail. In that case, repeat with a more dilute solution. The important point to be observed is' the immediate removal of free bro- min by the introduction of the ferrocyanide solution. Buchbinder claims that the test is sensitive to 0.02 mg. of quinin. The thalleoquin test is also given by quinidin, cuprein, hydroquinin, hydroquinidin, and diquinicin, but not by quinamin, cinchonin, nor cin- chonidin. Pilocarpin, cocain, atropin, codein, and strychnin do not inter- fere with the reaction but morphin does, as well as antipyrin and caffein, in certain proportions. Caffein can of course be removed by shaking it out of an acid solution and morphin may be eliminated if the quinin is separated by ether, in fact the quinin should be as pure as possible before applying this test. When an alcoholic solution of iodin is added to an acid solution of quinin sulphate, a precipitate of the black or bronze iridescent iodo-sulp- phate is produced known as Herapathite. The directions for this test in the U. S. Pharmacopoeia are as follows: 0.7 gram of quinin are dis- solved in 15 mils of acetic acid, 6 mils alcohol and 0.5 mil sulphuric acid added and the solution heated to boiling, 7 mils of saturated solution of iodine in alcohol are added and the mixture allowed to cool when the Herapathite will gradually separate. It may be filtered off, washed, and recrystallized from hot alcohol. Quinidin, cinchonin, and cinchonidin also gives the iodosulphate, but that of quinin is much more insoluble in alcohol, and is soluble in water with difficulty. 0.2 gram of quinin dissolved in 1 mil of dilute sulphuric acid, diluted with water to 20 mils, the acid neutralized with ammonia, treated with 1 drop of hydrogen peroxide and 1 drop of copper sulphate 10 per cent and boiled, yields an intense red color which slowly changes to blue and finally to green. Quinidin also gives tins test. 0.2 gram of quinin dissolved in 2 mils of concentrated sulphuric acid and treated with 0.5 mil hydrogen peroxide gives a deep yellow color gradually fading to light yellow which persists for a considerable time. Quinin gives a well-defined precipitate with potassium chromate sepa- rating from a solution of 1-200; quinidin is also precipitated by this reagent as a fairly insoluble precipitate, but the chromates of cinchonin ALKALOIDS DERIVED FROM QUINOLIN 159 and cinchonidin are much more soluble. The use of this compound has been proposed for the quantitative estimation of quinin, but its value is questionable and its use even for qualitatively distinguishing quinin from the other bases is not satisfactory. Potassium iodide does not give a precipitate with quinin. This will distinguish quinin from quinidin and cinchonidin but not from cinchonin. Potassium ferrocyanide gives a reddish-brown color, but no precipitate with dilute solutions of quinin; with quinidin a white flocculent precipi- tate is formed; with cinchonin and cinchonidin a white precipitate is thrown down soluble in excess. Mercuric chloride does not precipitate dilute solutions of quinin until a considerable excess has been added while quidinin, cinchonin, and cin- chonidin give immediate precipitates. The ordinary alkaloidal reagents, Mayer's reagent, Wagner's reagent, potassium bismuthic iodide, phosphomolybdic and phosphotungstic acids, gold and platinic chlorides, and picric acid all give precipitates with quinin. With phosphotungstic acid a pink fluorescence is also noticeable. Quinin picrate melts 125-126° C. This salt should always be made and identified when the identity of quinin is in question. Salts of Quinin Quinin forms a number of crystallizable salts, several of which are official, and these and many others are used medicinally. There is also a series of acid salts, usually much more soluble than the normal com- pounds, and on this account much preferred for certain purposes. The most important salt is the sulphate, (C2oH 2 402N 2 )2H2S04 • +7H2O which is perhaps the most extensive^ employed alkaloidal salt in the realm of medicine, rivaling morphin sulphate-, cocain hydrochloride and strychnin sulphate, and possibly exceeded by the two former only on account of their vast illegitimate use. The commercial salt is seldom free from small quantities of allied bases. Cinchonidin is sometimes added in amounts of about 1 per cent in order to produce the fluffy appearance so much desired. The standard allows for minute quantities of these alka- loids and tests are included in the pharmacopoeia for their detection if present in excessive amounts and as the drug analyst may be called upon to pass upon the purity of this body some detailed points about the vari- ous tests will be of interest. This salt occurs in white lustrous or shining, fragile, needle-like crys- tals, very compressible and becoming dark if exposed continually to the light. When chemically pure the appearance is modified, the needles being less bulky and the salt is known as the " heavy sulphate." It is but sparingly soluble in cold water, requiring over 700 parts of the solvent to effect solution ; in hot water it dissolves much more readily and on cool- 160 ALKALOIDAL DRUGS ing the crystals separate. In alcohol its solubility is about 1-65 cold and 1-3 boiling, and it dissolves with ease in a mixture of chloroform — abso- lute alcohol 2-1. It is sparingly soluble in chloroform and practically insoluble in absolute ether and petroleum ether. It is always slightly alkaline to litmus even when crystallized out of acid solutions. The commercial salt always contains a little cinchonidin and hydro- quinin and may also contain cinchonin, quinidin, and amorphous bases, and to detect the presence of undue quantities of these other alkaloids various tests have been proposed. The test which has been most exten- sively adopted for this purpose in the different pharmacopoeias is the so- called ammonia test originally proposed by Kerner. It depends upon the fact that, while quinin sulphate is less soluble in water than the sulphates of the accompanying bases, quinin itself when freshly precipitated by ammonia is much more soluble in the latter than the other free bases. The procedure consists in treating 5 mils of an aqueous solution of the salt, saturated at 15° C, with 10 per cent ammonia water and noting the amount which will yield a clear solution. The limit varies, thus our own standard and the Italian is 7 mils, the French 5, the Netherlands 4.5 and the German 4. The results are only empirical as it is difficult to dissolve out cinchonidin sulphate from crystals of quinin sulphate, and cinchonidin sulphate forms a double salt with quinin sulphate in crystallizing. Tutin ] has made an exhaustive study of this test working from the pure salt which he prepared by repeated crystallization and manipulation of the alkaloid through the d-camphorsulphonate and the d-bromcamphorsul- phonate. He shows that the minimum amount of 10 per cent ammonia which will yield a clear solution at 15° C, with 5 mils of a solution of pure quinin sulphate saturated at 15° C. is 4.4 mils. He states that it is impos- sible to meet the German standard and that the French and Netherlands standards are more stringent than is desirable. It is evident then that our standard is the fairest where the manufacturer is concerned, and other things being equal, is safe for the consumer. Tutin belives that a mini- mum of 6 mils is a reasonable requirement, and leans towards the manipu- lation of the French Pharmacopoeia, by which 1 gram of the salt is dis- solved by boiling with 30 mils of water, cooled to 15° C, allowed to stand | hour and then 5 mils of the clear liquid treated with the ammonia. Tutin proves also that the basicity of the salt has the same effect as an impurity, and hence commercial salts which frequently contain a little free alkaloid, may appear to be far less pure than is actually the case. Finally alkaline sulphates if present will decrease the solubility of the quinin sulphate to such an extent that an impure product may appear purer than one which is strictly pure. The presence of inorganic salts may be ascertained by evaporating the aqueous solution to dryness and examining the residue for 1 Amer. J. Pharm., 1912, 84, 484. ALKALOIDS DERIVED FROM QUINOLIN 161 alkali bases and ammonia. Tutin concludes that this test is valueless as a means of ascertaining the purity of any salt of quinin, other than the normal sulphate, but in the case of this salt it is the only means of detect- ing hydroquinin without actually isolating that alkaloid. The next scheme to be considered in the examination for impurities will be the test for the separate alkaloids as elaborated in the British Pharmacopoeia. Test for Cinchonidin and Cinchonin. — Dissolve 4 grams of the quinin sulphate in 120 mils of boiling water. Cool the solution slowly to 50° with frequent stirring. Separate, by filtration, the purified quinin sul- phate which has crystallized out. Concentrate the nitrate by evapor- ation until it is reduced to 10 mils or less; transfer to a small stoppered flask and when cool, shake with 10 mils ether and half that amount of solution of ammonia. Set aside in a cool place for not less than twenty- four hours. Collect the crystals which consist of cinchonidin and cin- chonin combined with quinin on a tared filter, wash with a little ether, dry at 100° and weigh. Those should not amount to more than 0.12 gram. If this test is performed with ordinary ether an admixture of 7 per cent cinchonidin will escape detection, but if absolute ether is used 3 per cent of this alkaloid can be detected. Test for Quinidin. — Dissolve 1 gram of the quinin sulphate in 30 mils of boiling water, cool, and filter. To the solution add solution of potas- sium iodide and a little 90 per cent alcohol to prevent the precipitation of amorphous hydriodides. Collect any separated quinidin hydriodide wash with a little water, dry, and weigh. The weight represents about an equal weight of crystallized quinidin sulphate. Test for Cuprein. — Shake the recrystallized quinin sulphate obtained in testing the original quinin sulphate for cinchonidin and cinchonin with 25 mils of ether and 6 mils solution of ammonia, and to this ethereal solu- tion separated, add the ethereal liquid and washings also obtained in testing the original sulphate for the two alkaloids just mentioned. Shake this ethereal liquid with 6 mils of 10 per cent sodium hydroxide, adding water if any solid matter should separate. Remove the ethereal solu- tion, wash the aqueous solution with more ether and remove the ethereal washings. Add diluted sulphuric to the aqueous liquid heated to boil- ing until exactly neutral. When cold collect any crystallized sulphate of cuprein on a tared filter, dry and wash Test for Cinchonin and Amorphous Alkaloids. — Dissolve 1 gram of quinin sulphate in 30 mils of boiling water. Add 1 gram sodium potas- sium tartrate. Allow to cool with frequent shaking and filter. The solution when evaporated to small bulk should give little or no precipi- tate with solution of ammonia. Another type of test useful for detecting the presence of cinchonin 162 ALKALOIDAL DRUGS and quinidin has been proposed by Hesse and depends on the difference in their solubliities in chloroform. The quinin sulphate is dried at 100° C. and 1 gram agitated with 15 mils of alcohol-free chloroform, the solvent is filtered and 10 mils evaporated; which should not leave a residue of more than .035 gram. If the residue is crystalline and less than the above weight it may be tested for cinchonin and quinidin by warming it with 5 mils of water, adding 0.5 gram of sodium potassium tartrate, cooling, filtering, and treating the filtrate with an equal volume of ammonia water. If quinidin or cinchonin are present a precipitate will be formed. Cin- chonidin sulphate if present will swell up into bulky needles when treated with chlorofrom, but it does not dissolve, and the solvent may be separ- rated by pressure. If a solution of quinin sulphate is treated with an excess of potassium chromate and allowed to stand several hours, the quinin is almost entirely precipitated. On filtering and adding sodium hydroxide to the filtrate the solution will remain clear if the quinin is pure, but will become tur- bid in the presence of 1-2 per cent of allied alkaloids. The examination of quinin sulphate for amorphous alkaloids has been studied by DeVrij, who recommends adding ammonia to an acid solu- tion of the salt and then shaking out with ether in order to obtain the free alkaloids. After evaporating the solvent the residue is treated with N/10 oxalic acid in sufficient amount to convert the alkaloids into neu- tral oxalates, the liquid is evaporated over the steam-bath and the resi- due dried. The neutral oxalates are then dissolved in chloroform and the solution filtered and treated with a few drops of water when crystals of quinin oxalate will appear in the solvent. In the case of a pure sample the water will remain clear and uncolored, but if amorphous alkaloid is present the water will be colored yellow. A number of methods have been proposed for determining the purity of quinin sulphate by reference to its rotatory power, but there are so many conditions which impair the accuracy of any observations of this property that the writer has decided to omit them. The determination of the amount of alkaloid in a sample of quinin sulphate is readily effected by dissolving a weighed quantity in water slightly acidulated with sulphuric acid, adding a slight excess of ammonia and shaking out three times with ether. The combined ethereal solu- tions are washed with water and the solvent solution filtered into a tared dish, the ether evaporated and the residue brought to a constant weight at 100° C. If desired the gravimetric estimation may be checked titri- metrically and for this purpose attention is called to Elvove's procedure ;* about 0.2 gram of the alkaloidal residue is dissolved in an excess of dilute hydrochloric acid 4 per cent, the liquid completely evaporated, the sur- i Hyg. Lab. U. S. P. H. & M. H. Service Bui. 54 ALKALOIDS DERIVED FROM QUIXOLIN 163 face film being broken up from time to time with a glass rod, the residue allowed to remain in the water-bath for three hours, then dissolved in 10-20 mils of water, 3 drops phenolphthalein added, and titrated with standard sodium hydroxide until the solution develops a faint pink color. At this point one more drop of the indicator is added and if the solution at once assumes a very deep pink color, standard acid is added until the color remaining is only light pink, the alkali equivalent of the acid just added being deducted from the total alkali added first. Two molecules of sodium rrydroxide are equivalent to one molecule of quinin. The method is applicable to quinidin, cinchonin, and cinchonidin. Iron and Quinin Citrate The Pharmacopoeia formerly recognized two products under this title, one readily soluble and the other slowly soluble, and both containing, 11.5 per cent quinin and 13.5 per cent metallic iron. The ninth revision, however, has deleted the less readily soluble compound. These bodies are really mixtures of iron citrate and quinin citrate containing more or less ammonium citrate. The more readily soluble of the two occurs in thin transparent scales of a greenish-golden-yellow color and the other in reddish-brown scales. They are both partially soluble in alcohol. The iron does not respond to the ordinary qualitative tests, but if the quinin is precipitated by ammonia and the filtrate acidulated with hydro- chloric acid the Prussian blue reaction will be given with potassium fer- rocyanide. The official assay's for quinin and iron are as follows: Dissolve about 1 gram of Iron and Quinin Citrate, accurately weighed, in 20 mils of distilled water in a separator, add 5 mils of ammonia water and 10 mils of chloroform, and shake the separator for one minute. Allow the liquids to separate, draw off the chloroform layer through a small filter moistened with chloroform, into a tared dish, and shake the resid- uary liquid a second and a third time with portions of 10 mils each of chloroform, passing the chloroform through the filter each time and finally washing the filter with 5 mils of chlorofrom. Evaporate the combined chloroform solutions, redissolve the residue in 3 mils of alcohol, again evaporate and then dry the residue to constant weight at 100 c C. This residue corresponds to not less than 11.5 per cent of the amount of Iron and Quinin Citrate taken for the assay and conforms to the identity tests under Quinin. Assay for Iron. — Heat the aqueous liquid, from which the quinin has been removed in the manner just described, on a water-bath, until the odors of chloroform and of ammonia have disappeared, allow to cool, and dilute with distilled water to a volume of 25 mils. Transfer the liquid to a glass-stoppered bottle, add 15 mils of hydrochloric acid and 3 grams of potassium iodide, and, after securely closing the bottle, allow the mix- 164 ALKALOIDAL DRUGS ture to stand for thirty minutes at 40° C. Then cool and titrate with sodium thiosulphate, using starch as indicator. It shows not less than 13 per cent of Fe. Each mil of N/10 sodium thiosulphate used corresponds to 0.005584 gram of Fe. Each gram of Iron and Quinin Citrate corresponds to not less than 23.3 mils of N/10 sodium thiosulphate. Quinin and Urea Hydrochloride C 2 oH2 4 N 2 02 • HCI+CH4N2O • HC1+5H 2 0. This salt in aqueous solution is used to a limited extent for hypodermic injections and exerts an anesthetic action similar to that of cocain. It occurs in white crystals which are very soluble in water. QUINIDIN Quinidin is the stereoisomer of quinin. It rotates the plane of polarized light to the right, melts 168-171.5°, the latter figure being obtained with the anhydrous alkaloid. It crystallizes from alcohol and ether with water of crystallization and may be rendered anhydrous by heating to 120°. It is readily soluble in ether and alcohol, somewhat soluble in chloroform and benzol, and slightly soluble in water, It resembles quinin in its reactions, but differs from quinin in giving a very sparingly soluble precipitate with potassium iodide. It also gives a permanent bulky precipitate when its solution is treated with chlorin water, potassium ferricyanide, and ammonia. Quinidin picrate melts 137-138° C. Quinidin is marketed in the form of the sulphate which contains two molecules of water. This salt is soluble in 20 parts of chloro- form. It may be examined for other alkaloids by dissolving 0.5 gram in 10 mils water and adding .5 gram neutral potassium iodide, stirring, cooling, and filtering after half an hour from the precipitated hydriodide; the filtrate is then treated with 1-2 drops of ammonia water and if a pre- cipitate is thrown down the presence of other alkaloids is indicated. The commercial salt usually contains traces of hydroquinin and hydro- quinidin. 0.2 gram quinidin treated with 2 mils concentrated sulphuric acid and 0.5 mil hydrogen peroxide gives a yellow color turning to a deep orange and gradually fading to colorless. HYDROQUININ AND HYDRO QUINIDIN The two alkaloids differ constitutionally from quinin and quinidin by containing two more hydrogen atoms, and occur with them in the com- mercial salts. They are stable to permanganate and may be separated ALKALOIDS DERIVED FROM QUINOLIN 165 by treating the mixture with this reagent which destroys quinin and quin- idin. Hydroquinin is laevorotatory and in the anhydrous state melts 172°. Hydroquinidin is dextrorotatory and melts 166-167°. They both give fluorescent solutions with acids and respond to the thalleoquin tests. QUINAMIN AND CONQUINAMIN These two isomeric bodies occur in a number of different species of Cinchona and are probably present in small amounts in commercial Cin- chona alkaloids. They are both dextro, the latter more strongly, and are soluble in the ordinary organic solvents. Quinamin melts 172° and conquinamin 121-123°. Quinamin hydrochloride reduces gold chloride solution. Mulliken describes the following reaction of quinamin. If a solu- tion of the salt strongly acidified with sulphuric acid is smeared over white paper and held over a watch glass containing sulphuric acid and potas- sium chlorate, the lines become olive green in color and on exposure to air turn blue. CUPREIN Cuprein occurs in the bark of Remijia pedunculata and in other species of Remijia. It differs from most of the other alkaloids of this family in uniting with alkalies and some of the less basic elements to form definite soluble salts, this property being due to the presence in its molecule of an hydroxyl group having a phenolic character. Its alcoholic solution gives a reddish-brown color with ferric chloride. It is sparingly soluble in ether and chloroform, but when precipitated from its acid solution by ammonia can be removed from the mixture by these solvents. Fixed alkalies dissolve the precipitated alkaloid, and ether cannot remove it from this solution. Cuprein melts 198° after drying at 125° C, is laevorotatory, gives the thalleoquin test, but its acid solutions do not fluoresce. It forms stable crystalline compounds with the cinchona bases, one of which, homoquinin, has been carefully studied. The latter is obtained when molecular pro- portions of quinin and cuprein are dissolved in dilute acid, precipitated with ammonia and shaken out with ether, which leaves the double body on evaporation. Its salts differ from those of either of its two components. Homoquinin may be separated into its constituents by treating an acid solution with excess of fixed alkali and shaking out the quinin with ether, the cuprein remaining in solution. Cuprein forms two classes of salts the normal being but slightly sol- uble in water. The relationship of cuprein to quinin is the same as that of phenol to its methyl ether. The transformation of cuprein into quinin is effected / 166 ALKALOIDAL DRUGS by treating a solution of cuprein in methyl alcohol with sodium and then with methyl iodide, the temperature, starting from zero, being gradually raised during several hours. Under these conditions quinin itself is not formed, but quinin mono- and dimethyl iodides. When operating in a closed vessel with an excess of methyl iodides only the latter body is produced. Methyl-cuprein-dimethyl iodide agrees in all its properties with quinin-dimethyl iodide, as is shown by the following figures: Quinin dimethyl iodide Synthetical Natural Melting-point (with partial decomposition) 167-168° C. —150.8 41.34 167-168° C. Rotatory (a) D Percentage of iodine —151.6 41.77 If the methyl iodide be replaced by methyl chloride, free quinin is formed. A mixture of one molecule of cuprein, one atom of sodium and one molecule of methyl chloride dissolved in methyl alcohol, is heated to 100° C. in a closed tube. The product of the reaction is evaporated to dryness, washed with a dilute soda solution in order to remove any unal- tered cuprein, and finally extracted after conversion into sulphate of quinin, the product resembles the natural article in all respects, ALKALOIDS OF THE CUSCONIN CLASS This group is found in Cusco bark and probably in other species of Remiiia. Chick gives them all the same formula, C22H26N2O4, but Pictet gives one more carbon atom to aricin, cusconin, and concusconin. Pictet's summary of their characteristics is as follows: Chairamin occurs in needles or prisms, which in the hydrous con- dition melt at 140°, in the anhydrous at 233°. It is dextrorotatory. Chairamidin is amorphous and dextrorotatory and in the anhydrous condition melts at 126-128°. Conchairamin is a very weak base, dextrorotatory, melting in the anhydrous condition at 120°. Conchairamidin occurs in laevorotatory needles melting in the anhy- drous condition at 114-115°. Aricin crystallizes from alcohol in prisms melting at 188°. It is lsevo- rotatory in neutral solution, inactive in hydrochloric acid. Cusconin crystallizes in prisms melting at 110° and is laevorotatory. Concusconin is a dextro base melting at 206-208°. Cuscamin and cuscamidin have been mentioned, but a description of their properties is lacking. ALKALOIDS DERIVED FROM QUINOLIN 167 QUINICIN AND CINCHONICIN Quinicin and cinchonicin are amorphous bases resulting respectively when quinin and cinchonin are heated under certain conditions. Quinicin is dextrorotatory, gives the thalleoquin reaction, is readily soluble in alco- hol and ether, and forms a number of crystalline salts. It is not pre- cipitated by Rochelle salt, but gives insoluble precipitate with potassium thiocyanate, and a white precipitate with hypochlorites. Cinchonicin resembles the above base in most of its properties but does not give the .thalleoquin test. Quinicin melts 60° and cinchonicin 58-59° C. DIQUINICIN AND DICINCHONICIN These two bases, also amorphous, make up the greater part of quin- oidin. The former may be considered an anhydride of quinin or quinidin and the latter as a double molecule of cinchonin or cinchonidin, though this has been disputed. Diquinicin gives the thalleoquin test and its acid solutions are fluorescent, dicinchonicin does not answer these tests. DeVrij has worked with the amorphous bases and distinguishes them by the behavior of their neutral oxalates rendered anhydrous at 100° C. Quinicin oxalate is almost insoluble in cold chloroform, and though it dis- solves in the hot liquid it is deposited again on cooling. Cinchonicin oxalate is readily soluble in cold chloroform and on adding a few drops of water the solution solidifies. The oxalates of the natural amorphous bases dissolve easily in chloroform and the solution does not solidify on adding water. Quinoidin is the name given to a brownish-black resinous-appearing mixture of amorphous cinchona alkaloids which has a somewhat limited use in manufacturing pharmacy. The alkaloids composing it are those left in solution after the crystalline alkaloids have been removed. It is soluble in dilute acids, alcohol, and chloroform. Several of its salts, including the borate, citrate, hydrochloride, sulphate, and tannate are commercial articles. EXAMINATION OF CINCHONA BASES FOR IDENTIFICATION Though these alkaloids are of common occurrence in medicinal prep- arations, the individuals are among the most unsatisfactory of chem- ical bodies to identify. They follow one another closely in their solubil- ities, and it is next to impossible to effect a complete isolation of any one by ordinary analytical reactions. We state that cinchonin and cinchon- idin do not give fluorescent solutions with acids, and yet there is probably no commercial salt of these alkaloids which will not give a fluorescent, solution. It is well known that these same alkaloids do not give the 168 ALKALOIDAL DRUGS thalleoquin test, but unless one is fortunate in his manipulation, he will often fail to get this reaction with quinin and quinidin, and when work- ing with small quantities perhaps be unable to obtain it at all. Any alkaloidal residue obtained from a preparation containing an extract of cinchona will give a fluorescent solution with dilute sulphuric acid, and will more than likely contain quinin, cinchonin, cinchonidin, and perhaps quinidin in varying proportions. In fact in many instances the worker can report the presence of cinchona alkaloids, and that is about as far as he can go. Any method of separation of the main alkaloids requires a sample which, in quantity, is almost prohibitive unless it happens to be a " pure " salt, and is of no value for the relatively small residues which one ordinarily obtains. If the residue in question is transparent, colorless, and hard like a var- nish with perhaps here and there the appearance of a crystalline form, it probably consists entirely of quinin. A good thalleoquin test will indi- cate quinin or quinidin. If a neutral solution gives a copious precipitate with potassium iodide and the filtrate yields but a small quantity of alka- loid after treatment with alkali and shaking out with ether, the substance is chiefly quinidin. Cinchonidin will give a curdy precipitate under similar conditions while that obtained with quinidin will be granular if the orig- inal material is pure, but of course cinchonidin does not respond to the thalleoquin test. Quinin and quinidin when dissolved in concentrated sulphuric acid and treated with 0.5 mil hydrogen peroxide give deep-yellow solutions, becoming orange in the case of quinidin and then gradually fading to yellow, the quinin solution holding its color over an extended period. When cinchonin or cinchonidin are treated under like conditions they give light-yellow solutions which soon fade. The iodosulphates of the cinchona base differ considerably in their solubilities and appearances; quinin iodosulphate is black and iridescent and but slightly soluble in water or dilute alcohol, quinidin iodosulphate is reddish brown and much more soluble, so that it often takes consider- able time to precipitate; the cinchonidin compound is slightly less sol- uble and the cinchonin compound more soluble than that of quinidin. Potassium ferrocyanide gives a white flocculent precipitate with quini- din, a reddish-brown color with quinin, and a white precipitate soluble in excess with cinchonin and cinchonidin. The directions of rotation of polarized light is to the right with quini- din and cinchonidin and to the left with quinin and cinchonin, but this property is of little value as a means of identification unless the sample is comparatively large. It will be noted from the above paragraphs that the tests for cinchonin and cinchonidin are much less positive than those for quinin and quinidin. ALKALOIDS DERIVED FROM QUINOLIN 169 If one has sufficient residue it should be carefully purified, heated to 125°, allowed to stand in a desiccator and its melting-point taken. Quinin melts at 171-172°, quinidin 168-171.5°, cinchonin 250-265°, and cinchon- idin 202-203°. In all cases the picrate should be prepared and its melt- ing-point determined. With the above notes in mind the examination of an alkaloidal resi- due, suspected of being composed of one or more members of the Cin- chona group, may take the following course. If the sample under con- sideration contains an extract of any of the Cinchonas or Remijias, a solu- tion of the alkaloids in dilute sulphuric acid will almost invariably have a bluish fluorescence and the alkaloidal residue obtained therefrom will contain several different alkaloids in varying proportions. If there is sufficient quantity for preliminary tests, small portions of the residue should be treated separately with bichromate and sulphuric acid, form- aldehyde-sulphuric acid, nitric acid and evaporated and the residue treated with a few drops of alcoholic potash in order to insure the absence of some of the main groups of alkaloids. The next step should be the determi- nation of the melting-point as described in the preceding paragraph. Then the test with sulphuric acid and peroxide should be tried, followed by the thalleoquin, herapathite, the potassium iodide and the ferrocyanide tests and the melting-point of the picrate determined and with the data obtained the identity of the individual can be very closely established. The vari- ous other properties of the individual can then be tested and checked with the descriptive data. In order to effect a separation of the main alkaloids when they occur together, Chick, in the new edition of Allen, describes DeVrij's scheme, which was also used in the former edition. It will be described here in brief, as it is a valuable method, not only for separating the alkaloids themselves, but as an aid in establishing the identity of an individual. The sample, which should not amount to less than 2 grams, in a state of fine division, is treated in a small Erlenmeyer flask with ten times its weight of absolute ether and well shaken, the flask stoppered and allowed to stand for twelve hours. It is then filtered into a tared dish, and the residue washed with a small quantity of ether, and the filtrate evaporated to dryness and weighed. This residue consists of quinin, quinamin, amor- phous alkaloids, and traces of quinidin and cinchonidin, the portion insoluble in ether being composed of cinchonin, cinchonidin, and quinidin. The residue containing the quinin is then dissolved in 10 parts of 50 per cent alcohol acidified with 1/20 of sulphuric acid and treated with an alcoholic solution of iodin as long as a precipitate is obtained, avoiding an excess of the reagent. If much quinin is present a black precipitate of herapathite is immediately produced but if the quantity is small some time is required for its appearance, and in this case only a small quantity 170 ALKALOIDAL DRUGS of iodin should be added and the solution well stirred and allowed to stand twelve hours. The precipitate is then filtered off, washed with strong alcohol, decomposed with sulphurous acid and the quinin liberated with ammonia and extracted with ether. The alcoholic filtrate and wash- ings are then rendered colorless with sulphurous acid and carefully neu- tralized with sodium hydroxide, the alcohol evaporated, the residue made alkaline and shaken out with chloroform. After evaporating the solvent the amorphous alkaloids will dissolve in a limited amount of ether, leav- ing most of the quinidin and cinchonidin behind. The bases which were insoluble in ether are then dissolved in dilute sulphuric acid, the solution exactly neutralized with sodium hydroxide, an excess of saturated solution of Rochelle salt added, cooled to 15° C. and allowed to stand for one hour. If cinchonidin is present, crystalline streaks of the tartrate form, the solution is filtered off and washed with 5 per cent solution of Rochelle salt. The filtrate is concentrated to its original volume, a drop of acetic acid is added and an excess of a saturated solution of potassium iodide. The mixture i& allowed to stand for two hours at 15° C. with frequent stirring, and if quinidin is present, a pre- cipitate of the hydriodide is formed which is filtered, washed with cold water, and the alkaloid recovered by treatment with ammonia and agi- tation with chloroform. The filtrate and washings from the hydriodide precipitate is then made alkaline with sodium hydroxide and the cin- chonin extracted with chloroform. As illustrative of the peculiarities of this group it may happen that when working with the mixed alkaloids an ethereal solution will yield a quantity of a molecular combination, for instance, of quinin and quinidin. When these crystals are dissolved in sufficient sulphuric acid to form the neutral salt, quinin sulphate will crystallize and the mother liquor will contain quinidin sulphate. The crystalline compound above mentioned will be but slightly soluble in ether, though it is more soluble in ethereal solution of quinin and such a solution frequently exhibits supersaturation, remaining clear for some time and then suddenly giving a cloud of crys- tals. Quantitative Estimation. — The quantitative estimation of the indi- viduals of this group presents little difficulty; the alkaloids are compar- atively stable, they will stand considerable manipulation, and it is only when they occur together with some strong base like strychnin that their separation becomes involved. In order to determine quinin or the allied bases in tablet triturates or plain compressed tablets of the sulphate or bisulphate, the sample amounting to 10 or 25 tablets should be introduced into a 250-mil sepa- rator of the Squibb type, moistened with water, shaken until disinte- grated and then made alkaline with ammonia. About 25 mils of ether ALKALOIDS DERIVED FROM QUINOLIN 171 °> II o 'o P CO p3 > jo S -t5 I &H R ft o CO m CD S ta '51 © o o o a >> 1 o CO .s > CD cd o ft fl o s CI o O II +3 03 bC CD Pi £ pq 2 ■2 £ 2 £ -2 © ft o3 o3 +?, •$ © s « J a a ft cd cd ^ ^ ^ P2 ,c ^3 ,G O C CM CO I rC CD -2 o £ ft -° ~ £ « OS ° r< £ oo wi CO I CO 00 CM ^_ '-+3 O '55 Ph 9 •* 03 ^ o O 2 £ ft « fl1 1=" CD s £ ■p cj -o ■5 o 3 -s-g 13 ft ^ "3 © kT -+3 © ^ 1 ft '© B ft o <5 CD » ® ,n J p p 1) ."^ ft ft ^ ? sS >H >i ^ Q £ '3 eg .»? aj cd o S fe P ft ^ fe •> CD l lt| >^ o ^ CD CD o3 o3 ft ^ bfi ^ .s o .±3 CD &.&■§• O O CD ft ft » ffl ffl ? •+3 +3 O p3 pS ^ 13 P o3 pq CD c3 -t-3 ft So ft ^ o S 3 s .52 CD CD - CD CD > 1-3 -*J O ft ft S s ° ^ Ph o g ^ ^ 13 ^ >H ^ ^ >H d a 3 o if ft o bC ^_ C o3 lo- ll ?.2 H Ph '3 ^ o3 o o «8 fe fl 2 O C -P3 Th O O -g p=J p=! ft ft ■Tj 03 03 2 O O OpU3 O Ph Ph •rt CD CD J J 3 2 Ph PQ 172 ALKALOIDAL DRUGS are added and the separator shaken, the aqueous mixture drawn off into another separator and the operation repeated twice, which is sufficient to remove all of the alkaloid. The ethereal solution may then be con- centrated to about 50 mils and shaken out three times with 15 mil portions of dilute sulphuric acid, the quinin liberated from the acid with ammonia and shaken out three times with 25-mil portions of ether, the combined ether shake-outs washed with water, filtered into a tared dish, evaporated, and the residue weighed. This residue is sufficiently pure to render a titration unnecessary. With pills and coated tablets the disintegration will probably be slower, but the general plan described above should be followed, though to avoid emulsification the first extraction may be accomplished with Prolius mix- ture. If Prolius is used the solvent should be evaporated and the residue dissolved in dilute acid as the removal of an alkaloid from Prolius solu- tion by acid is unsatisfactory. Quinin sulphate in capsules is usually mixed with milk sugar. The contents of the capsules should be poured into a separator and treated as under tablet triturates. When a liquid preparation is under examination and it has been found that cinchona bases are the only alkaloidal constituents, a quantity amount- ing to 25 or 50 mils should be washed into a separator, treated with excess of ammonia and shaken out with ether or Prolius, depending on its behavior, and the alkaloids purified in the usual way. Some liquid prepa- ations contain but small quantities of the alkaloids, and for products of this type, which include various bitters and quinin whiskies, a generous sample amounting from 100-500 mils should be concentrated to about 50 mils, then made alkaline and the determination continued. Where quinin has been identified in tablets which also contain resin- ous drugs, the sample should be thoroughly ground up in a mortar and extracted four or five times with alcohol, the alcoholic solution evaporated in the presence of a little acidified water, and when the alcohol has been driven off sufficiently to precipitate the resins, the liquid is filtered into a separator and the dish and filter washed three times with 15-mil portions of hot dilute acid. From this point the determination may follow the regular scheme. Quinin will often be found in combination with the belladonna alka- loids and with strychnin and less often with the opium and ipecac alka- loids. The manipulation of a product in which the belladonna alkaloids have been found must be carried out with care as these bodies are readily decomposed. In order to obtain the total alkaloidal content the pill or tablet should be ground up in a mortar and extracted with alcohol, the solvent cautiously evaporated until the liquid is in small bulk, treated with dilute sulphuric acid and filtered into a separator. Ammonia is then ALKALOIDS DERIVED FROM QUINOLIN 173 added in excess and the alkaloids shaken out with chloroform, the latter is filtered into a tared dish, evaporated, the residue dried in a vacuum desic- cator and weighed as total mixed alkaloids. The quinin may then be estimated by the same procedure recommended for separating cocain aid strychnin described in detail under Nux Vomica alkaloids, page 52, the belladonna alkaloids being thereby destroyed and the quinin being recovered. If the analyst is working with a quinin morphin mixture the prelim- inary procedure will be similar to that already detailed, and then the quinin may be obtained alone by shaking it out with ether from a solu- tion made slightly alkaline with fixed alkali and the morphin obtained subsequently after acidulating, rendering ammoniacal and shaking out five times with chloroform-alcohol 2-1. QUININ FROM STRYCHNIN No very satisfactory method has yet been evolved for accurately and completely separating quinin and strychnin. This important mixture is quite common. It has been proposed to remove the strychnin as the ferrocyanide, but the precipitate invariably carries down with it a portion of quinin. Another procedure involves precipitating the quinin as oxa- late, but it has been found impossible to wash out the stiychnin without dissolving some of the quinin and it is impossible to separate the latter by means of a solvent when it occurs in a drug mixture with stiychnin. The methods in use for the separation and determination of quinin and strychnin in admixture are described under the Nux Vomica Alkaloids. The following titration method was devised by Buchbinder for mix- tures of quinin and strychnin, and the author believes that the same pro- cedure might be used for mixtures of quinin with such other alkaloids as give a neutral (to methyl red) hydrochloride and are not effected by treatment with acids. Dissolve the isolated alkaloid in alcohol; add a few drops of concen- trated hydrochloric acid and evaporate to apparent dryness on the water- bath. Dry in an oven at 110° until there is no reddening of a wetted piece of blue litmus paper held over it for a minute while in the oven. Dissolve in a little water and titrate with N/50 alkali. There is formed the dihydrochloride of quinin which is acid toward methyl red, the monohydrochloride being neutral. Difficulty is experi- enced in the recognition of the end-point, and this uncertainty is even more pronounced with the chloride than with the sulphate. However, with the aid of blanks, and after experience even without their aid, an accurate determination can be made. One mil of N/50 acid or alkali =6.49 mg. anhydrous quinin =7.57 mg. quinin-f-3H 2 = 8.73 mg. quinin sulphate +7H 2 0. 174 ALKALOIDAL DRUGS Nishi l suggested a method for determining quinin by precipitating it as the citrate out of ethereal solution by means of an ethereal solution of citric acid, and Cockburn and Black 2 worked with it and considered it very accurate. The precipitated citrate after standing twenty-four hours is filtered onto asbestos, washed with ether and weighed. SEPARATION OF THE CINCHONA BASES Leger 3 has worked on the determination of quinin in mixtures with other cinchona alkaloids and proposed a method which he considers very accurate for mixtures of the sulphates of quinin, cinchonidin, and cin- chonin. The total alkaloids in the form of basic sulphates are treated with a boiling mixture of 5 mils of water and 75 mils of a solution of quinin sulphate saturated in the cold until completely dissolved and then set aside for twenty-four hours. In this way the sulphates of quinin and cinchonidin are separated and the sulphates of the other bases remain in the mother liquor. The crystalline sulphates are then filtered onto a Gooch, washed with saturated quinin sulphate and finally with 2 mils water, then dried spontaneously in the air, then at 30° C. and weighed. 0.7 gram is then brought into solution in 40 mils of a boiling saturated solution of the tartrates of quinin and cinchonin, 2 mils of a sodium-potas- sium tartrate 35 per cent are added, and after twenty-four hours the pre- cipitate of double tartrates is collected on two counterpoised filters, washed first with saturated solution of cinchonidin and quinin tartrate, and then with 5 mils of water. The filters are drained and pressed between bibulous paper, the contents withdrawn and the filters and tartrates dried separately in the air and weighed. The index of rotation is then deter- mined according to Ondemann's formulae, 215.8XzXl31.3(100-:r) = 100Xam, in which am = the observed rotation of the mixed tartrates. Hence x= — , in which 215.8 is the rotatory index of quinin tartrate .215 . o — lo .o and 131.3 that of cinchonidin tartrate. The quantity of quinin tartrate T. Q. in the mixed tartrates T.M. will be therefore = T.M. (100 am -13 130) ^'~ 100(215.8-131.3) ' and the corresponding amount of quinin Q will be: 324 X T.M. (100am- 13130) * 408X100(215.8-131.3) ' 324 being the molecular weight of quinin and 408 that of its tartrate. 1 Analyst, 1909, 34, 443. 2 Analyst, 1911, 36, 396. 3 J. Pharm. Chim., 1904, 19, 427. ALKALOIDS DERIVED FROM QUINOLIN 175 QUININ DERIVATIVES Aristochin. Diquinin carbonic ester. Aristoquin CO(C20H 2 3N 2 O2)2 Aristochin occurs as a white, tasteless powder melting at \189°/ C, insoluble in water, sparingly soluble in alcohol and ether, and somewhat soluble in warm alcohol and chloroform. It combines with one and two molecules of hydrochloric acid to form soluble salts. Acids gradually decompose it with liberation of quinin. It is prepared by treating quinin dissolved in pyridin or chloroform with carbonyl chloride, or by heating together quinin and phenol carbonate in the proportion of 2-1. Chinaphenin Phenetidin quinin carbonic acid ester. CCKNHC6H4OC2H5) (C 2 oH 2 3N 2 02) This derivative is prepared by the action of quinin on p-ethoxyphenyl carbonic acid chloride. It is a white, odorless, tasteless powder, difficultly soluble in water, but readily soluble in alcohol, ether, chloroform, and benzol, and dissolving in acids to form salts. It is decomposed by acids with liberation of quinin. It gives the thalleoquin test and a yellow iodo- sulphate. Euquinin. Quinin Ethyl Carbonate. Euchinin C2H5OCOOC20H23N2O Alkyl esters of the cinchona alkaloid carbonic acids are prepared by heating the alkaloids with an alphyl ester of an alkylcarbonic acid. Thus, the ethyl ester of quinin carbonic acid is obtained by heating quinin with phenylethyl carbonate, dissolving the product in benzene, removing phenol by dilute ammonia, extracting the ethyl ester by a dilute acid, and precipitating by alkali. The product, C2H5O • CO • OC20H23N2O, forms white needles, which melt at 95° C, sparingly soluble in water but readily soluble in alcohol, ether, and chloroform. It is slightly alkaline in reaction and forms bitter salts with acids. Its solution in dilute sul- phuric acid is strongly fluorescent, it gives the thalleoquin test, but not the herapathite reaction. On warming with sodium hydroxide and iodine, iodoform is produced. Euquinin is practically tasteless and forms a tasteless tannate. Saloquinin Quinin Salicylic ester. Salochinin. Salicylquinin. When quinin is heated with phenyl salicylate (salol) in an oil-bath 176 ALKALOIDAL DRUGS at 170-190° C, phenol distills and the quinin ester of salicylic acid remains. The product is dissolved in chloroform and shaken with 1 per cent acetic acid in order to remove unchanged quinin. OH • C 6 H4 • CO • OC6H5+C20H24N2O2 = C 6 H 5 • OH+OH • C 6 H4 • CO • OC2oH 23 N 2 0. The compound is a white crystalline, odorless and tasteless powder melting at 140° C, soluble in chloroform, hot alcohol, and benzene, little soluble in ether and cold alcohol. Ferric chloride colors the alcoholic solution reddish-brown. The corresponding cinchonidin compound melts at 65-70° C, its acid sulphate forms white needles which melt at 165° C. Its acid solutions are precipitated by alkalies and the usual alkaloidal reagents. Saloquinin salicylate is prepared by the addition of salicylic acid to a hot alcoholic solution of saloquinin. It is a white tasteless powder melting 182-183° C, sparingly soluble in water, soluble in benzol, chloro- form, and hot alcohol. Acid quinin dibromsalicylate, C 2 oH24N 2 022(C 6 H2Br20H • COOH) , known as Bromoquinol, occurs as yellowish crystals melting 197-198° C. and soluble with difficulty in water, alcohol, and ether. Quinin phytin This product is obtained by neutralizing anhydroxymethylene-diphos- phoric acid (phytin) with quinin and evaporating in vacuo. / H / \)— PO(OH) 2 O C20H24N2O2 \ /O— PO(OH) 2 CH< It is a yellowish crystalline powder, bitter, soluble in water with fluores- ence, insoluble in alcohol, ether, benzol, and chloroform. It is an anti- pyretic. Quinin Lygosinate CO(CH : CH.C 6 H4-C 2 oH24N202)2 Quinin lygosinate is prepared by the reaction of quinin hydrochloride with sodium lygosinate and is a quinin compound of dioxy-dibenzal-ace- tone. It is a bright orange-red amorphous powder, with a faint odor and bitter taste, melting at 114° C, slightly soluble in water, readily in alcohol, chloroform, and benzol, and decomposed by acids and alkalies. ALKALOIDS DERIVED FROM QUINOLIN 177 It dyes cotton a bright yellow. On warming, the odor of benzaldehyde is developed. It may be separated into its constituents by shaking with alkali, removing the liberated quinin with ether, and on acidifying the lygosin separates as a yellow oil. It is employed as a styptic and bactericide, and applied as a dusting powder, on gauze, and in glycerin suspension. Guaiaquin. — Quinin Guaiacolbisulphonate, C6H4O2CH3HSO3C20H24N2O2, is a yellow, bitter powder soluble in water, alcohol and dilute acids. Guaiaquinol. — Quinin Dihydrobromoguaiacolate, C20H24N2O2 • 2HBr • C6H4OHOCH3, occurs as yellow hygroscopic crystals, readily soluble in water. Quinaphthol. — Quinin betanaphthol monosulphonate, C2oH 2 4N20 2 (OHCioH 6 S0 3 H) 2 , is a yellow crystalline powder, melting 185-186° C, soluble in alcohol and hot water. Quinin Eosolate (CgH7S30i2)(C2oH24N202), is the neutral salt of tri- sulphoacetyl guaiacol, a yellow, bitter amorphous powder, soluble in alco- hol and slightly in water. Quinin Ethyl Sulphate or Sulphoninate C20H24N2O2C2H5SO4, occurs in white crystals readily soluble in water. J. Hesse has recently prepared a new compound of phenol with quinin bisulphate. If carbolic acid be added in equivalent proportion to a hot aqueous solution of quinin bisulphate, on cooling at first an oily mass separates out, above which delicate white needles are gradually formed, of the composition C20H24N2O2SO3C6H6O+3H2O. This com- pound is very unstable. If it be dissolved in hot water, on cooling the first named normal salt crystallizes out. Quite in accordance with this is the behavior of the acid quinin resorcinol sulphate, the acid quinin quinol sulphate, the acid quinin pyrogallol sulphate, and the acid cin- chonidin pyrogallol sulphate. The author further prepared and de- scribes the normal quinin orcinol sulphate, quinin catechol sulphate, cin- chonidin quinol sulphate, as well as the quinin resorcinol, quinin catechol, and quinin pyrogallol hydrochlorides. They are beautifully crystallized compounds and some of them excellent febrifuges. - YOHIMBE, QUEBRACHO, PSEUD OCINCHONA AFRICANA, ANGOSTURA, ALSTONIA, GEISSOSPERMUM The barks of several trees belonging to the Rubiacese, Apocynacea* and Rutacese are credited with febrifugal, tonic, and aphrodisiac proper- 178 ALKALOIDAL DRUGS ties. The drugs contain alkaloids possessing properties which in some instances are quite similar to each other, but as yet they have not been classified chemically. To avoid confusion, the data have been assembled under one heading, and placed next to Cinchona. Some of the drugs resemble Cinchona in appearance, and the alkaloids derived therefrom have similar physiological properties, though their chemical reactions are often more like those of the Nux Vomica bases. The botanical identity of the plants from which the drugs are derived is not conclusive in every case, neither is the identity of the bases, as cer- tain of the latter bear a close relation to each other and are perhaps iso- meric or even identical. These drugs are employed as bitter tonics, nerve tonics, and aphro- disiacs, and will be found in small amounts in alcoholic liquids recom- mended for recuperative and restorative purposes, often in combination with Turnera aphrodisiaca (Damiana). ALKALOIDS OF YOHIMBE BARK The bark of the Yohimbe or Yumbehoa tree, Corynanthe Yohimbe (Rubiacese), contains yohimbin and other bases as yet unstudied. The especial microscopic characteristic of yohimbe bark is the struc- ture of the secondary bark, which contains numerous yellowish-white bast fibers, regularly arranged, distinguishing yumbehoa bark from cin- chona bark, otherwise similar. The powdered bark (fine and moder- ately fine only are considered) is characterised by (1) the numerous pore- free bast fibers, with complete absence of stone cells, (2) the presence of greatly thickened porous and almost pigment-free cork cells, (3) the brown- walled, almost starch-free parenchyma, together with reddish-brown lumps of coloring matter. Cinchona barks are distinguished by the appearance of their bast fibers; cinnamon bark by the color, presence of stone cells, and high starch content. Yohimbin This alkaloid, which seems to be the chief base of the Yohimbe group, has been the subject of considerable research, though as yet its constitu- tion is undetermined. Its formula has not been definitely settled, but it appears to be either C22H28N2O3 or C21H26N2O3. The latter value is the same as that determined for corynanthin, the alkaloid of Pseudocin- chona africana, and quebrachin. The latest researches indicate that corynanthin is isomeric with yohimbin and dextro-quebrachin. When yohimbin is heated two hours with alcoholic potash, a methyl group is split off and the potassium salt of an acid remains in solution, which crystallizes from water in glassy prisms. This body is called nor- yohimbin or yohimboaic acid and forms salts with both bases and acids. ALKALOIDS DERIVED FROM QUINOLIN 179 Yohimbin is not simply a methyl ester of yohimboaic acid, esterification with different alcohols shows that two alkyl groups are taken up and one molecule of water is split off. Corynanthin is also a methyl derivative, and on saponification yieids an acid having the same composition as yohimboaic acid. Yohimbin crystallizes in the dark from absolute alcohol in anhydrous white needles melting at 247-248°. It is dextrorotatory, readily soluble in alcohol, ether, and chloroform, slightly in petroleum ether, benzol, and water. Its salts with hydrochloric and nitric acids are used in medicine, the latter being but sparingly soluble in water. Yohimbin residues give two reactions which deserve special consider- ation on account of their resemblance to those of stiychnin, and which might lead to confusion and possibly erroneous conclusions if the analyst has but a small quantity of material at his disposal. On adding sulphuric acid to a residue, a yellow color is obtained, which on adding potassium bichromate becomes purple, changing to blue, red, and finally green; if the quantity is considerable the first color is indigo-blue, changing rapidly to olive-green. Nitric acid gives a yellow solution, which becomes orange on evaporation; this residue treated with alcoholic potash yields a pur- ple color momentarily, then chocolate and on warming almost black; as the last portions of alcohol evaporate there is an odor of orange-flower. Yohimbin residues do not have the intense bitter taste that is character- istic of strychnin, and they are readily distinguished by the microscopic forms of the salts formed with gold chloride and other reagents used in the identification of stiychnin. A solution of yohimbin in concentrated sulphuric acid gives an intense orange with calcium hypochlorite. Formaldehyde-sulphuric gives a dark brown color. Yohimbin gives precipitates with most of the alkaloid precipitants, most of the compounds are amorphous, including those with gold and pla- tinic chloride. Chromic acid precipitates a mass of fine yellow crystals sol- uble in ammonia. Picric acid throws down yellow microscopic crystals which soon agglomerate and stick to the sides of the container. An alcoholic solution gives a white precipitate with bromine water. The precipitate obtained with mercuric chloride is crystalline and dissolves in water when the solution is diluted. Nessler's reagent gives a white amorphous pre- cipitate and reduction takes place with ammoniacal silver nitrate. Yohimbin hydrochloride is an anesthetic, but there is no likelihood of confusing it with cocain hydrochloride, after precipitating the alkaloid and subjecting it to the proper tests for identification. The alkaloidal residue from yohimbe bark probably contains one or more bases in addition to yohimbin. 180 ALKALOIDAL DRUGS QUEBRACHO ALKALOIDS The bark of Aspidosperma Quebracho-bianco (Apocynacese) contains aspidospermin, aspidospermatin, aspidosamin, quebrachin, hydro-que- brachin, and quebrachamin. The drug is not of common occurrence in medicine, though the extract is used extensively in tanning, and the composition and properties of the bases have been subjected to but little research. Quebrachin probably occurs in the racemic, lsevo, and dextro forms, the latter being apparently identical with yohimbin. The reactions of the bases may be summarized as follows: Aspidospermin with sulphuric acid and lead peroxide gives a brown color changing to purple-red. When boiled with perchloric acid an intense red color results, the reaction probably depending on the presence in the acid of impurities having oxidizing power. Platinic chloride gives a blue precipitate which becomes violet on boiling with excess of the reagent. Potassium chromate produces a yellow precipitate which turns green on exposure to air. Hydro-quebrachin gives a yellow color with sulphuric acid, and the same reaction with perchloric acid as aspidospermin. The chloroplatinate is yellow and dissolves in boiling hydrochloric acid with a brown red color, depositing a blue precipitate on standing. Quebrachin gives a bluish solution with sulphuric acid, turning blue and brown with bichromate. With perchloric acid the color is yellow. Quebrachamin gives a violet color with sulphuric acid and bichromate and a yellow to yellowish-red with perchloric acid. Aspidospermatin gives with perchloric acid the same color as aspi- dospermin, but the precipitate with platinic chloride is yellow. Aspidosamin gives a brown color with sulphuric acid, turning blue with bichromate, and a fuchsin red color with perchloric acid. ALKALOID FROM PSEUD O CINCHONA AFRICANA Chevalier in 1897 called attention to a bark used for febrifugal pur- poses by the natives on the Ivory Coast. Its botanical identity was unknown, but from its resemblance to Cinchona he gave it the name Pseu- docinchona africana. Further study showed that it contained at least two alkaloids, one of which was crystalline and is probably isomeric with yohimbin, and the other amorphous. The former has been called cory- nanthin. On demethylation it yields an acid-like body apparently iden- tical with yohimboaic acid, and in other respects it bears a close relation- ship to yohimbin. It crystallizes from absolute alcohol in colorless hex- agonal plates, and from 60 per cent alcohol in elongated spangles with water of crystallization. It melts 241-242°, has [a] D -125° at 23° with the composition C21H26N2O3, which makes it isomeric with dextro-quebrachin. ALKALOIDS DERIVED FROM QUINOLIN 181 It is insoluble in petroleum ether, water and alkalies, but dissolves with greater or less facility in the organic solvents. It gives a blue color with sulphuric acid and bichromate, but its color tests have not been thoroughly studied. The characteristics of the bark from which it is derived have not been authentically reported. THE ANGOSTURA ALKALOIDS The bark of Cusparia officinalis, syn. C. trifoliata contains several alka- loids which have been studied by Troger and others. The isolated bases have never been employed for medicinal purposes, but an extract of the bark has a limited use as a tonic and febrifuge and will be found occasion- ally as an ingredient of bitters and restoratives. Troger x mentions five bases occurring in the drug: galipoidin, melt- ing 231°; cusparidin, melting 79°; galipidin, melting 111°; galipin, melt- ing 115°; and cusparin, melting 89-90°. He concludes that galipin and galipidin are dihydro compounds of cusparin and cusparidin respectively. In a previous article 2 he describes cusparein, melting 55-56°, and angos- turin, melting 231-233°. Later 3 he says that, besides certain oily bases, the extract of angostura bark contains only cusparin, galipin, and galipidin. Galipin was separated from cusparin by the difference in the solubility of the oxalates, that of galipin being readily soluble in water and crystalliz- ing only at considerable concentration, cusparin oxalate being soluble only in a considerable excess of boiling water. Galipin on oxidation with permanganate yields veratric and methoxy- quinolincarboxylic acids. The alkaloidal residue when dissolved in sulphuric acid and treated with a crystal of permanganate gives a reaction resembling that of strychnin. ALKALOIDS OF THE ALSTONIA BARKS Alstonia constricta (Apocynacese) of Queensland and New South Wales and A. scholaris, known as Dita bark of the Philippines, have been used in dysentery and intermittent fevers. The bases of the former, alstonin, melting about 195°, and porphyrin, melting 97°, show a blue fluorescence in acid solution and might be mis- taken for quinin. Hesse examined the Dita bark and found three bases, ditamin, echi- tamin, and echitenin. The second is a strong base and resembles ammonia in its chemical characters. Hesse considers the compound given by echi- tamin with one molecule of water as the hydroxide of a strong basic radicle, 1 Arch. Pharra., 240, 174. 2 Apoth. Zeit., 25, 957, 969, 977, 988. 3 Arch. Pharm., 250, 494. 182 ALKALOIDAL DRUGS echitammonium. The solutions are so strongly basic that they precipitate the hydroxides of copper, iron, aluminum, and lead, and decompose sodium and potassium chlorides, liberating the corresponding hydroxides. ALKALOIDS OF GEISSOSPERMUM The following bases have been isolated from the bark of Geissosper- mum vellosi (Apocynaceae), pereirin, melting 124°, geissospermin, and vellosin. The melting-point of geissospermin has been reported as 160° and as 189°, consequently the chemistry of this group is somewhat con- fusing. Under the name Pao-pereira this bark is used in Brazil as a febrifuge. With the possible exception of yohimbin, the known reactions of the bases described under this group of drugs are, from an analytical stand- point, very meager and unsatisfactory, and capable of misinterpretation. In forensic w x ork the advantage is all on the side of the chemist who is working for the party that knows the ingredients of the mixture in. ques- tion, and he can of course plan his tests and interpret his reactions accord- ingly. With the chemist who takes the product as an unknown mixture the problem is entirely different, and as these preparations usually con- tain but a meager quantity of the drug, by the time he has come to dif- ferentiate between the several possible bases, he will find that his material is exhausted. To the analyst who finds himself in this position a few words of caution are necessary; the first is not to confuse those bases with strychnin and the second is to refrain from stating positively the source of the alkaloids found unless he has worked with knowm specimens side by side with the sample under investigation and is prepared to meet all possible criticisms from his adversaries. It is a simple matter to iden- tify strychnin, as it yields several well-defined crystalline salts with alka- loidal precipitations, all of which can be easily identified under the micro- scope, w T hile the precipitates given by the bases herein described are mostly amorphous. If strychnin occurs with these bases it is more than possible that the analyst will miss the latter and come in for a round of undeserved criticism and sarcasm from the opposition when the case is summarized. CHAPTER VII ALKALOIDS DERIVED FROM ISOQUINOLIN THE OPIUM ALKALOIDS AND THEIR DERIVATIVES Morphin, C17H19NO3 Codein, C18H21NO3 Pseudomorphin, (Ci7HisN03)2 Thebain, C19H21NO3 Papaverin, C20H21NO4 Codamin, C20H25NO4 Laudanin, C20H25NO4 Laudanidin, C20H25NO4 Laudanosin, C21H27NO4 Tritopin, (C 2 iH 2 7N0 3 )20 Meconidin, C21H23NO4 Lanthopin, C23H25NO4 Protopin, C20H19NO5 Cryptopin, C2iHi 3 N05 Papaveramin, C21H21NO5 Narcotin, C22H23NO7 Gnoscopin, C22H23NO7 stereoisomer Oxynarcotin, C22H23NO8 Hydrocotarnin, C12H15NO3 Xanthalin, C20H19NO5 The average relative proportions of some of these bases in the drug are approximately as follows: Per Cent Morphin 9 Narcotin 5 Papaverin 0.8 Thebain 0.4 Codein 0.3 Narcein 0.2 Cryptopin . 08 Laudanosin . Per Cent Pseudomorphin. . . .0.02 Laudanin 0.01 Lanthopin 0.006 Protopin 0.003 Codamin 0.002 Tritopin 0.0015 ...0.0008 OPIUM The opium used in the manufacture of morphin and its accompany- ing alkaloids and for pharmaceutical preparations comes almost exclu- sively from Turkey and Asia Minor. It is the exuded juice of the black poppy (Papaver somniferum), which is gathered in a partially dry, gummy mass and sent into the trade in cakes of from 1 to 4 lbs. These cakes are usually wrapped with poppy or dock leaves and packed in cases with layers of dock capsules. The customs officials become very expert in the sam- pling of opium by the eye alone, and can tell by simply cutting into a cake whether it contains excessive moisture or extraneous substances, and is 183 184 ALKALOIDAL DRUGS of high or low grade. It is regarded as inferior if it is blackish in color, has a weak or empyreumatic odor, a sweet or slightly nauseous and bitter taste, a soft, viscid, or greasy consistency, a dull fracture, or an irregular appearance from the admixture of foreign substances. In the case of good opium, the lumps are usually hard on the outside, but still soft within, the internal color being light brown, and the interior containing but few, if any, dock capsules. On cutting open and tearing apart the lump, numerous minute shiny tears will sometimes be observed. The odor is pleasant and characteristic. Opium is adulterated with chunks of lead, stones, bullets, sand, clay, and other weight-producing substances, sugar, starch, tragacanth, fruit pulp, extract of licorice, poppy, and other plants and vegetable substances of a resinous or saccharin nature; and if it has been kept under damp conditions it will have become moldy. The composition of good opium is about as follows: Per Cent Moisture 8-30 averaging 20 Ash 4-8 Gum and soluble substances other than alkaloids. 40-60 Morphin 6-15 Narcotin 4-8 Other alkaloids 0.5-2 Meconic acid 3-8 Resins 5-10 Fat 1- 4 and it should yield 55-60 per cent of extractive matter to cold water based on the dry product. Smoking opium is no longer imported legitimately, but it is probably illegally made in this country, and smuggled in to a limited extent. The product is an aqueous extract of opium evaporated down to the con- sistency of a thick molasses, and is similar in every way to the old U. S. P. extract of opium. Smoking opium from China averages about 6.5 per cent morphin, while that made from Smyrna gum runs from 16 to 18 per cent. The sampling of opium requires considerable care, as the determi- nation of the value or condition of the entire lot or case is often dependent on the assay. Squibb recommends that every fifth lump should be taken, except the very small ones, and then every tenth lump of these be sepa- rated, a cone-shaped piece cut from each, the apex of the cone being near the center of the lump. A narrow strip is then cut from the side of each cone, the strips collected together in a cone, and this sample used for the determination of the moisture and morphin. The methods of assaying opium for its morphin content are described in the chapter on Drug Assays. ALKALOIDS DERIVED FROM ISOQUINOLIN 185 Kerbosch 1 has made an interesting investigation of the occurrence and distribution of certain of the alkaloids in the poppy plant. The seeds con- tain traces of narcotin and an amorphous alkaloid and three days after germination notable quantities of narcotin are present, soon followed respectively by codein, morphia, papaverin, and thebain. The flowering plant up to the time of ripening contains narcotin, papaverin, codein, and morphin in all its organs with the exception of the hairs. The latex varies in composition in different parts of the plant. Morphin, codein, meconidin, codamin, laudanin, laudanidin, laudano- sin, protopin, and cryptopin are all strong bases and narcotic or tetanic in their action, the others are weak bases and have little or no poisonous activity. They are present in the drug in acid combination to a large extent, the acid radicles being chiefly meconic and sulphuric. The drug analyst will seldom be concerned with the identification or determination of the entire list. Morphin, codein, thebain, narcotin, narcein, and papa- verin are the only individuals with which familiarity is necessaiy, and in addition to these bases meconic acid is of moment, as its identification is an important factor in establishing the presence of opium in a preparation. The recognition of this group is easy, either alone or in mixtures. In medicinal preparations one will find that morphin, opium extract, and codein, and in addition to these some of the derivatives, heroin, apo- morphin, and dionin, are used to a considerable extent. They are all use- ful for diminishing pain and inhibiting secretions except that of the skin, and are generally narcotic and will be found in cough mixtures, lozenges, and soothing syrups, diarrhea mixtures, neuralgia remedies, anodynes, coryza mixtures, consumption remedies, habit cures, and in a variety of imported foreign drug products, notably Chinese remedies. Several prod- ucts having a household reputation contain these bases, among which may be mentioned Dover's powder, paregoric, laudanum, sun cholera mixture, brown mixture, white pine cough syrup, and chlorodyne. Considering the products separately, opium will be found alone in laudanum or tincture of opium, fluid opium, wine of opium, and some elixirs of a similar nature having different trade-marked names, " cures " recommended for the opium habit, and in pills. It occurs in combi- nation with camphor, oil of anise, and glycerin in paregoric, or camphor- ated tincture of opium,- this combination being in some respects similar to the well-known proprietary " Bateman's Pectoral Drops," which also has been made up to include catechu. It is a constituent of ammoniated tincture of opium, similar to paregoric except that camphor is replaced by dilute ammonia. Black drop is essentially an acetic acid solution of the constituents of opium. It is combined with potassium carbonate, oil of sassafras, and molasses in a type of mixtures resembling Godfrey's 1 Arch. Pharm., 1910, 248-336. 186 ALKALOIDAL DRUGS Cordial; with magnesium carbonate, anise, nutmeg, peppermint, and castor oil in products of the Dalby's Carminative type; and in tinctures combined with ipecac. Opium in powdered form is mixed with powdered ipecac in the well-known Dover's powders, and with pepper, ginger, and caraway in compound opium powder. The different pill and tablet com- binations in which opium occurs are numerous, -some of the more common being with ipecac and mercury mass; asafetida and ammonium carbon- ate; calomel, camphor, and lead acetate, or in place of the latter tannin or hyoscyamus; guaiac and mercuric chloride; mercurous iodide, lead acetate, phosphorus, Digitalis with and without quinin or ipecac; ipecac, quinin and belladonna; licorice, benzoic acid, camphor, tartar emetic and anise in brown mixture; calomel and ipecac; copper sulphate, ipecac, and squills; potassium iodide, potassium arsenite, Lobelia, and belladonna in asthmatic remedies; bismuth subnitrate and carbolic acid; quinin, ammonium chloride, camphor, belladonna, and aconite; Krameria, bis- muth subnitrate, and licorice; Hyoscyamus, Hamamelis, tannin, thymol, helonias, salicylic acid, boric acid, alum, and eucalyptol in leucorrhea mix- tures; white pine, wild cherry, squill, senega, ipecac, Sanguinaria, potas- sium nitrate, and methyl salicylate; capsicum, rhubarb, camphor, and oil peppermint in sun cholera mixture; terpin hydrate, guaiac, wild cherry, and belladonna; aloin, Capsicum, aconite, quinin, ipecac, and calomel in cold remedies; and quinin, ammonium chloride, camphor, belladonna and aconite. This list does not by any means cover the field of combinations, new formulas are constantly being introduced, but it will show in a general way the type of mixtures on the market, and the class of substances with which opium is combined. Opium should be looked for also in supposi- tories, in admixture with tannin, menthol, camphor, and boric acid, and in ointments recommended as local applications for croup and pneumonia where it occurs with quinin, camphor, phenol, and turpentine. Morphin in the form of sulphate, hydrochloride, nitrate, meconate, tartrate, phthalate, and valerianate, occurs alone in pills and tablets and will sometimes be found in snuff powders and as a remedy for the mor- phin habit. It also occurs as the oleate. Morphin sulphate and atropin sulphate in various proportions are combined in hydopermic tablets to a large extent; and it is used in conjunction with cocain in dental tablets, and to a limited amount with strychnin. It is also present in place of opium in some of the mixtures mentioned above ; chlorodyne mixture con- tains morphin hydrochloride, nitroglycerin, Cannabis, Hyoscyamus, Cap- sicum and peppermint; morphin bromide compound contains morphin and scopolamin (" hyoscin ") hydrobromates with monobromated cam- phor; uterine astringent and antiseptic tablets consist of alum, zinc sul- phate, tannin, boric acid, morphin sulphate and extract Hydrastis; medi- cated lozenges contain ipecac and morphin sometimes with other ingredi- ALKALOIDS DERIVED FROM ISOQUINOLIN 187 ents; white pine compound, a liquid cough remedy contains morphin acetate, sassafras, Sanguinaria, spikenard, wild cherry, white pine bark and balsam of poplar buds and sometimes chloroform and tar are used; morphin sulphate will be found in combination with laxative drugs in liquid preparations sold as cures for the morphin habit. Codein has a much more restricted use than opium or morphin, but the combinations in which it does occur are sold to a large extent. It occurs alone in pills and tablets and in hypodermic tablets, especially as the phosphate and is often combined with acetanilid, caffein, bromides and sodium salicylate; with antipyrin, spartein, strophanthus and caffein; and with colchicin and sodium salicylate. In the liquid form it is mixed with acetanilid, caffein, and bromides, and often replaces morphin in cough mixtures of the white-pine type. It is said to have been used to some extent in confectionery sold for throat troubles. Heroin is employed as a substitute for morphin in cough mixtures and is also mixed with terpin hydrate in elixirs, and sold alone in tablet tritu- rates and hypodermic tablets. Apomorphin is employed chiefly in the form of hypodermic tablets. The other alkaloids of opium or their derivatives are either used by themselves or have no commercial use other than in their extract form. Morphin CH 3 H H 2 | C C N HC C CH CH 2 I II I I HOC C C CH 2 V V \/ C C CH I I I O C CH 2 H C /\ H OH Morphin crystallizes out of alcohol in prisms containing one molecule of water. It is lsevorotatory, slightly soluble in water, ether, chloroform, and benzol, but readily soluble in alcohol, alcohol-chloroform mixture, amyl alcohol, acids, and alkalies. Its water of hydration is given off at 100° and the alkaloid melts at 254° C. when heated rapidly. When heated slowly it begins to melt at 247° with decomposition. Morphin with its water of hydration melts at about 230° C. 188 ALKALOIDAL DRUGS It is a strong tertiary base and also a monatomic phenol, dissolving in alkalies to form salts with one atom of the metal which are decomposed by carbon dioxide or ammonia. This property of forming salts with alka- lies is used to good advantage in separating morphin from other alkaloids. It forms diacetyl and dibenzoyl derivatives. On strong oxidation with dilute nitric acid it gives a dibasic acid, C10H9NO9, and this on further treatment with fuming nitric acid is converted into picric acid. On methyl- ation it is changed to codein, the group being introduced on the phenolic hydroxyl. Thebain may be considered as oxymethyl codein and the rela- tionship of these three bodies may be represented as follows : r— oh r — 0CH3 f — OCH3 C15H14ON — CHOH C15H14ON —CHOH C15H14ON ' — COCH3H II I — CH [— CH 2 I— CH 2 Morphin Codein Thebain When fused with potassium hydroxide morphin gives protocatechuic acid. Acids, alkalies, and zinc chloride remove a molecule of water and convert it into apomorphin, which is soluble in ether and chloroform. Morphin is readily oxidized even by gold and silver salts, and iodic acid. On oxidation by weak oxidizing agents, pseudomorphin is formed according to the reaction, 2Ci 7 Hi 9 N0 3 +0 = (Ci 7 Hi 8 N03)2+H 2 It is precipitated by the usual alkaloidal precipitants, but not by potas- sium chromate or ferrocyanide, and gives some interesting color tests both in aqueous solution and as a dry residue. A neutral aqueous solution gives a deep blue-green color with ferric chloride, changed to green with excess of the reagent and disappearing on the addition of acids or alcohol or on heating. Pseudomorphin gives a blue color and codamin a dark green. An aqueous solution reduces iodic acid with liberation of iodin, which will dissolve in carbon bisulphate or chloroform with a violet color. Mor- phin will reduce potassium ferricyanide, being itself oxidized to pseudo- morphin, and if an aqueous solution slightly acidified is added to a solution of potassium ferricyanide and ferric chloride a blue precipitate or color- ation will be produced due to the formation of Prussian blue. Iodic acid followed by ammonia gives a mahogany color which is a positive test, while the simple reduction is not necessarily characteristic of morphin. Iodic acid is reduced by extractive matter from animal tis- sues, some medicinal drugs and inorganic compounds. The iodic acid ammonia test, however, is distinctive according to Peterson and Haines; ALKALOIDS DERIVED FROM ISOQUINOLIN 189 they report its application to numerous extracts from putrefied animal matter of various kinds, and in no case was a fallacious indication obtained. The iodic acid test may be applied directly to a dry residue on a smooth porcelain surface. A drop of the reagent is added to a small quantity of the suspected residue and after standing ten minutes, any iodin is washed off by floating over it a drop or two of chloroform, repeating until the spot is colorless. When dry a drop or two of 10 per cent ammonia water is added, when a mahogany color indicates morphin. The decanted chloro- form is then evaporated and tested with a little starch paste, which will turn blue if free iodin is present. Strong nitric acid added to solid morphin turns it a deep red or orange- red color, the crystals dissolving to an orange-red solution, gradually fading on standing. A drop of stannous chloride added to the red solution pro- duces no change, differing from the brucin nitric acid color which thereby is changed to purple. Strong sulphuric acid gives only a faint pink color with morphin when both substances are pure, and the color soon fades. If a solution in concentrated sulphuric acid is warmed to 100° C. and then treated with concentrated nitric acid, a chlorate, chlorin water or sodium hypochlorite, a blue or purplish color is obtained, passing to deep red and gradually fading. This is known as Husemann's test and is very delicate. Chloral or bromal added to a solution of morphin in strong sulphuric acid, produce a deep purple color and Froehde's reagent a deep purple fading to slate. Ammonium persulphate in sulphuric acid gives pale orange. If morphin is treated with a little sugar, moistened with a drop of water and made into a paste and a drop of sulphuric acid is allowed to flow alongside the mixture, an intense purple color will develop at the point of contact, changing to violet and green to yellow With bichromate and sulphuric acid a greenish color is produced and with vanadium-sulphuric acid, colors from yellow, passing to violet brown and slate are obtained. A dilute solution of morphin treated with 1 mil each of 3 per cent hydrogen peroxide and dilute ammonia, followed by 1 drop of copper sul- phate solution 1-4 per cent gives a color varying from rose to red. Deniges recommends this reaction in testing for morphin directly. Apomorphin and oxymorphin react in a similar manner in syrups, but codein, thebain, papaverin, narcein, and narcotin give negative results. Solutions of morphin give characteristic crystalline precipitates with iodin solution, palladous chloride, picrolonic acid and other reagents and a microscopical examination of the forms of these compounds is one of the most valuable means of identifying the base and distinguishing it from its allies. 190 ALKALOIDAL DRUGS If morphin is dissolved in hydrochloric acid, a little sulphuric acid added and the mixture evaporated on an oil-bath at a temperature of 100-120° a purple color appears on the edges, and after the volatile acid is all evaporated a red color remains. On dissolving again in hydro- chloric acid and neutralizing with sodium bicarbonate a violet color is obtained. If hydriodic acid is added the color changes to green and on shaking with ether, the solvent becomes purple. When morphin is mixed with hydrastin and treated with a little con- centrated sulphuric acid, a faint pink color is given which soon fades, and then very gradually a reddish purple shade develops, which after some time changes to green. If a crystal of bichromate is added as soon as the mixed alkaloids have dissolved in the acid, a slate color appears, chang- ing to indigo blue and then to a deep purple which is quite permanent for some time and then gradually passes to brown. This test has become known as the Lloyd reaction, and might under some circumstances be mistaken for a strychnin test. However, neither morphin nor hydrastin give a purple color when evaporated with nitric acid and treated with alcoholic potash, which happens with strychnin. It is stated that the veratrum alkaloids when mixed with hydrastin and treated with sulphuric acid will give a violet color. Morphin is not removed from acid aqueous solution by solvents, and from alkaline liquids is extracted only by amyl alcohol or an alcohol- chloroform mixture. If the solution is made alkaline with ammonia under ordinary conditions minute amounts will be taken up by ether and chloroform, but in the presence of sodium or potassium hydroxide it is insoluble, and may thus be separated from most of the other alkaloids. It has been shown that an acid solution of morphin containing a little alcohol, saturated with sodium chloride and rendered alkaline with a slight excess of ammonia, will give up its morphin by shaking six to ten times with chloroform. It is well known that alkaloids in the freshly precipi- tated, or so called " nascent " condition, are far more readily soluble than when they have been allowed to crystallize. Morphin when dissolved in chloroform may be removed from this solvent by solutions of the caustic alkalies. Alkyl derivatives of morphin are easily produced by dissolving the base in alcohol and heating for two hours under a reflux condenser in the presence of the alkyl sulphate of potassium or sodium. Carbonic esters may be prepared by dissolving morphin in alcohol, adding alcoholic alkali and a slight excess of the alkyl chloro-carbonate. The reaction takes place at once with rise of temperature. The mixture is then neutralized with sulphuric acid, the alcohol distilled off, the resi- due dissolved in water and the ester of morphin carbonic acid liberated by alkali, and dissolved out in benzol. ALKALOIDS DERIVED FROM ISOQUINOLIN 191 Of the salts of morphin the acetate, hydrochloride and sulphate will be encountered most frequently. Morphin acetate contains three mole- cules of water and occurs as a white or yellowish powder, very soluble in water and partially decomposed on boiling or evaporating. Morphin hydrochloride contains three molecules of water which are lost at 100° C. The crystalline salt is in white needles or minute cubes. The sulphate containing five molecules of water is probably the compound which has the widest use. It crystallizes in bundles of silky needles, and as found on the market is usually in small cubes. It loses 3H2O at 100° and the remainder at 110°. Tin's is the form used to a large extent in making hypodermic tablets; for sale in J-ounce vials to those addicted to the habit; for mixing with sugar and other inert substances in snuffs; and for cough mixtures, and various pill and tablet formulas. It has been observed that commercial morphin sulphate sometimes contains an appreciable quantity of codein. This is due to imperfect methods of manufacture and is not an intentional adulteration. There are many other salts of morphin on the market but their use is comparatively limited. Morphinmethylbromide This product, known also as morphosan, closely resembles morphin in some of its properties. It forms white needle-shaped crystals, readily soluble in water, slightly in alcohol, and almost insoluble in ether and chloroform. It becomes anhydrous at 100-110°, and melts with decom- position at 264-265°. Its solutions give a blue color with ferric chloride and a blue precipitate with ferric chloride and potassium ferricj^anide. It dissolves in sulphuric acid with a yellow color, and in Froehde's reagent with a violet color soon changing to dark green. Nitric acid produces a blood-red color, and formaldehyde sulphuric a red-violet changing to blackish green. Its solution is not precipitated by ammonia and it gives a test for bromine on decomposing with nitric acid in presence of silver nitrate. Codein. C 17 H 18 (CH3)N03 Codein or methyl morphin occurs in white prismatic crystals. It crystallizes from water with one molecule of the solvent and melts under boiling water to an oily liquid. Anhydrous codein melts at 155°. It is fairly soluble in water, especially when hot, and also in ammoniacal solu- tions, the latter property distinguishing it from morphin and useful in separating it from that base. It is readily soluble in alcohol, chloroform, benzol, ether, and amyl alcohol. It is practically insoluble in petroleum 192 ALKALOIDAL DRUGS ether and only slightly soluble in fixed alkalies. Its solutions are alka- line in reaction and lsevorotatory. With dehydrating agents, codein either forms condensation products, or loses a molecule of water and is converted to apocodein, C18H19NO2. Codein resembles morphin in some of its color reactions, but is sharply distinguished from it in others, and in its solubility in the ordinary organic solvents. With sulphuric acid no color is produced but if a trace of arsen- ate, dilute nitric acid, or ferric chloride is present, a blue color is produced. With nitric acid a yellow color is obtained, the crystals assuming an orange color until dissolved. Formaldehyde-sulphuric acid gives a deep purple color so closely resembling the shade obtained with morphin that it can- not be used as a distinguishing test. Froehde's reagent produces no change at first, but a blue color gradually appears. Vanadium-sulphuric acid gives a green, and then gradually a blue color. Sulphuric acid con- taining ammonium selenite gives a green color; ammonium persulphate in sulphuric acid, orange. Pure codein does not reduce iodic acid; its solution does not give a blue color with a solution of ferric chloride, nor a blue precipitate with the latter and potassium ferricyanide. When dissolved in concentrated sulphuric acid and treated with a drop of 10 per cent sugar solution, a violet-red color appears which changes rapidly to deep red on heating over a water-bath. Codein picrate, prepared by precipitation from hydrochloric acid solu- tion and recrystallized from 10 per cent acetic acid, melts 195.5-196° C. Codein may be prepared synthetically from morphin, and may be considered a methyl derivative. Pseudomorphin Pseudomorphin sometimes occurs in opium, and may be prepared by the mild oxidation of morphin. In composition it may be considered as a product resulting from the condensation of two molecules of morphin with the loss of two atoms of hydrogen. It crystallizes in leaflets con- taining 3H2O, which decompose without melting. It is soluble in alkalies and ammonia, but insoluble in water, acids, alcohol, or ether. It is a non-poisonous weak base. It contains four hydroxyl groups and gives a tetra-acetyl derivative. Pseudomorphin will be of little concern to the drug analyst unless he becomes involved in a toxicological case where there is a question of its formation in the body as a condensation product of morphin. Its color reactions have been only imperfectly described. Hesse states that it gives a green color changing gradually to brown with sulphuric acid and sugar, and a blue to green with sulphuric acid containing a trace of iron. m ALKALOIDS DERIVED FROM ISOQUINOLIN 193 Papaverin H H c c H 3 CO— C C CH ! II I H3CO— C C N c c H I CH I C •\ HC CH I I HC C— OCH3 C I OCH3 The so-called papaverin group of the opium alkaloids includes most of the bases other than those previously described. They are all related to each other constitutionally and their structural groupings have, in some instances, been definitely established. Papaverin, narcotin, and narcein are the three most important and are the individuals with which the drug analyst may at times become concerned. They are all derivatives of isoquinolin, and their basic character is weak, standing thus in sharp contrast to morphin, codein, and thebain. Papaverin crystallizes in prisms or needles, melting 146-147°. It is inactive to polarized light. It is insoluble in water and alkalies, but dis- solves readily in hot alcohol, chloroform, benzol, and hot petroleum ether, and is somewhat soluble in ether. It is easily removed from an acidulated solution by chloroform and partially by ether. Narcotin is also removed from an acid solution by chloroform, and may be separated from papaverin by dissolving in oxalic acid and concentrating until the sparingly soluble acid oxalate of papaverin crystallizes out. Papaverin forms a very insolu- ble benzoate. This base gives with strong acids and oxidizing agents some well- marked color tests which are distinct from the colors given by narcotin and narcein, though it may be stated at this point that variations in color given by the latter may be due to the impurities present of which papaver- amin and cryptopin are of especial moment. It dissolves in concentrated sulphuric acid to a colorless solution, becoming violet on heating. Froehde's reagent gives a purple, gradually changing to blue; sulphuric 194 ALKALOIDAL DRUGS acid and bichromate purple, turning brown and then changing back to purple; formaldehyde-sulphuric acid purple changing to crimson; and ammonium vanadate in sulphuric acid purple, blue, green and finally deep blue. It dissolves in nitric acid to a yellow solution. Narcotin gives a purple color with formaldehyde-sulphuric acid which turns to slate and soon fades, but gives no purple tint with any of the other reagents above mentioned. Narcein gives no purple color with any of them. Ammo- nium persulphate in sulphuric gives yellow with papaverin. On mixing papaverin ferricyanide with formaldehyde-sulphuric acid, a light-blue color is produced, soon changing to violet and finally green, the color then fading to brownish yellow. A similar change of colors results when papaverin and potassium ferricyanide are mixed in the dry state, and treated with formaldehyde-sulphuric acid. Warren *, who first reported this reaction, subjected a number of alkaloids to this test and found that, with the exception of an uncertain base from San- guinaria, none gave a reaction like papaverin. However, if selenious acid be used as the oxidizing agent, the initial color produced by the Sangui- naria base is an intense purple, while papaverin when thus treated gives a fugitive greenish blue which becomes deep blue. Warren found that a mixture of potassium permanganate and papaverin treated with for- maldehyde-sulphuric acid gave a green color, almost instantly changing to blue, then deepening into an intense violet-blue which after some time becomes bluish green, then green and finally dirty brown. Mullikin states that the pure base prepared from the oxalate which has been repeatedly crystallized gives no color reactions with concen- trated sulphuric acid, Froehde's, Mandelin's or Erdmann's reagents, and that with formaldehyde-sulphuric acid, the color is a faint pink chang- ing to brown. He claims that the color reactions given by commercial papaverin are due to the presence of cryptopin. Papaverin gives precipitates with several of the alkaloidal precipi- tating agents, but in dilute solutions none with phospho-molybdic acid, and is not thrown down by potassium-cadmium iodide. An alcoholic solution of iodin added to an alcoholic solution of papaverin gives a crys- talline precipitate on standing; this precipitate is decomposed by alkalies and ammonia. It forms a very sparingly soluble ferricyanide and acid oxalate. The picrate melts 179-181°, and the picrolonate 220° C. When oxidized with permanganate, papaverin yields a large number of well-defined compounds, among them being a body to which the name of papaveraldin has been given. Its composition is C20H19NO5, melting at 210°, and it differs from papaverin in possessing one more oxygen and two less hydrogen atoms. It is apparently identical with xanthalin. It reacts with hydroxylamin and phenylhydrazine, and when fused with 1 J. Amer. Chem. Soc, 27, 1915, 2402. ALKALOIDS DERIVED FROM ISOQUINOLIN 195 alkalies is decomposed into veratric acid and dimethoxyisoquinolin. Another product of oxidation is papaveric acid, C16H13NO7, melting 233°. It is a dibasic acid containing a ketone group and on fusion with alkalies is converted to protocatechuic acid. Veratric and protocatechuic acids are among the final products of the direct fusion of papaverin with caustic alkalies. Hesse 1 has called attention to the fact that some of the samples of papaverin which he obtained had a percentage of carbon slightly above the normal even though he subjected them to repeated purification. The composition corresponded to C21H21NO4, and the alkaloid appeared to be more soluble in cold alcohol than was pure papaverin. Hesse has given the substance the name pseudopapaverin and believes that in some sea- sons it predominates while in others the normal form is obtained only. The complete synthesis of papaverin has been accomplished by Pictet and Gams. Papaveramin This alkaloid crystallizes in prisms melting at 128-129°; sightly soluble in water, alkalies, ether, and benzol, readily soluble in alcohol and chloro- form. It is of interest especially as an impurity of papaverin, which it follows very closely in its solubilities and other properties, and is probably the constituent of crude papaverin which causes violet-blue color with con- centrated sulphuric acid. Xanthalin This base is identical with papaveraldin, a product of the oxidation of papaverin with permanganate. It has been isolated from opium, though it is possible that it is formed from papaverin during the process of extraction. It is a crystalline powder, melting 2 08°, insoluble in water and alkalies, slightly soluble in alcohol and readily soluble in chloroform. Its salts have a yellow color. Laudain, Laudanidin, Laudanosin, Tritopin and Codamin These alkaloids are all closely related and are strong poisonous bases. The composition of laudanosin has been established as dextro-n-methyl- tetrahydropapaverin, laudanin is n-methyl-trimethylpaperverolin, and laudanidin is probably its lsevo modification. 1 Laudanin crystallizes from alcohol or chloroform in prisms, inactive to polarized light, melting at 166°, readily soluble in alcohol and ether. It contains a phenolic hydroxyl and a neutral solution of its salts gives a green color with ferric chloride. With pure sulphuric acid it gives a J. prakt. Chem., 1903, 68, 190. 196 ALKALOIDAL DRUGS faint pink tint, deepening if a trace of iron is present and turning to violet on heating. Nitric acid produces an orange-red color. Laudanin is not removed by chloroform from its solution in alkali hydroxides, but on adding ammonia the base is precipitated and may then be extracted. It forms a sparingly soluble hydriodide. When treated with methyl iodide in alkaline methyl alcohol, laudanin gives laudanin-methyl chloride and laudanin-methyl ester which is identical with z-laudanosin obtained from papaverin. Laudanidin closely resembles the former alkaloid, but is lsevorotatory and melts 177°. It may be separated from laudanin by means of its hydro- chloride, which is readily soluble in water; the hydrochloride of laudanin separates out from hydrochloric acid solution, especially if sodium chlo- ride is present to accelerate the precipitation. Its salts other than the hydrochloride closely resemble those of laudanin. Laudanosin crystallizes in needles, melting at 89°, soluble in alcohol, ether, chloroform, and benzol, and insoluble in water and alkalies. It is dextrorotatory. It gives no color with ferric chloride, and with sul- phuric acid alone and with oxidizing agents the reactions are similar to those given by laudanin. It gives a sparingly soluble hydriodide which serves as a very satisfactory means of separation. iV-methyl-tetra-hydro- papaverin, prepared synthetically, is identical in its chemical properties with laudanosin. It is a racemic body and may be separated into its constituents by quinic acid, the ^-compound being much less soluble in alcohol; the d-body is identical with natural laudanosin. Tritopin crystallizes in prisms from alcohol or in plates from ether, melting 182°. It is easily soluble in alkalies but is reprecipitated on add- ing excess of the reagent. It dissolves readily in chloroform and slightly in ether. Its color reactions with sulphuric acid are similar to those of laudanin. Codamin Codamin is a strong base, melting 121-126°, readily soluble in the ordi- nary solvents and alkalies and somewhat soluble in water. It gives a deep- green color with nitric acid and a greenish blue with sulphuric acid con- taining a trace of ferric chloride. Both laudanin and laudanidin are isomeric with codamin. Meconidin Meconidin is a strong base which occurs as a brownish-yellow amor- phous mass becoming liquid at about 58°. It is insoluble in water, but dissolves readily in alkalies and in the ordinary organic solvents. It is not removed from its solution in caustic alkalies by ether, but is shaken out of ammoniacal solutions with readiness. ALKALOIDS DERIVED FROM ISOQUINOLIN 197 Lanthopin Lanthopin is another of the minor alkaloids of opium and a weak base, soluble in alkalies, chloroform, ether, benzol, and alcohol, melting about 200°. It gives a colorless solution with sulphuric acid, darkening on warming, and an orange-red solution with nitric acid. It gives no color reaction with ferric chloride. Thebain Thebain is a very poisonous, strong, tertiary base, which, as we have already observed, is closely related structurally to morphin and codein. It contains no hydroxy 1 group, and is unaffected by acetyl chloride or phosphorus pentachloride. It crystallizes from alcohol in leaflets, melt- ing at 193 °, and is readily soluble in alcohol, ether, chloroform, and ben- zol, almost insoluble in water and alkalies, and insoluble in petroleum ether. In the regular scheme of analysis it will occur in the fraction obtained by shaking out the ammoniacal solution with ether. When heated to 130° it sublimes in caffein-like needles. Narcotin, narcein, and papa- verin do not sublime. Thebain differs markedly from codein and morphin in its color react- ions, giving a yellow with nitric acid and a red or reddish brown with sulphuric acid, Froehde's reagent, ammonium vanadate, and formalde- hyde-sulphuric acid. It is precipitated from an aqueous solution of opium by sodium salicylate, which forms a veiy sparingly soluble thebain salicylate. Dilute acids convert thebain into an amorphous base, thebanin, C18H19NO3, which is sparingly soluble in hot alcohol, and insoluble in the other ordinary organic solvents. The picrate, prepared as described under codein, melts 189-191° C. Protopin This is one of the minor alkaloids of opium, though it occurs in greater amounts in other drugs. It is of special interest from the fact that it is one of the few opium alkaloids that is not confined to that drug alone, but is quite widely distributed, being found in the root of Sanguinaria canadensis, Adlumia cirrhosa, Stylophorum diphyllum, Macleya cordata, and several species of Chelidonium and Corydalis. It is a strong nar- cotic base, crystallizing in needles from ether and chloroform, melting 202° (207° Mullikin), insoluble in water and fixed alkalies, slightly solu- ble in alcohol, ether, and benzol, but dissolving in ammonia and readily in chloroform. It gives a yellow to red color with sulphuric acid, and a deep violet with sulphuric acid containing iron oxide. It gives no color with ferric chloride. Mullikin states that the color with concentrated sulphuric acid is blue-violet changing to muddy violet with a green mar- 198 ALKALOIDAL DRUGS gin. Erdmann's reagent gives, according to the same authority, yellow, blue-violet, blue, green and yellow. It forms an amorphous aurochloride melting 198° C. Protopin appears to be identical with fumarin and macleyin. Cryptopin Cryptopin crystallizes from alcohol or ether in prisms, melting 213- 218°. It is insoluble in water, alkalies, and ammonia, slightly so in ether, alcohol, and benzol, but dissolves readily in chloroform. It is a strong base and possesses hypnotic and mydriatic properties. With sulphuric acid it gives a violet color, changing to green and yellow, and if the acid contains iron oxide the color is deep violet. It occurs as an impurity in papaverin and is probably responsible for some of the color reactions attributed to its host. Erdmann's reagent gives a violet pink, changing to gray and yellow; Froehde's reagent, violet changing to blue-green, green and after some time yellow; formaldehyde-sulphuric acid, violet changing to brown. Salts of cryptopin, when dissolved in water, usually produce a gelatin- ous mass on cooling, and on standing the mass becomes crystalline. The picrate melts 215°. Cryptopin is closely related to protopin. It contains two methoxyl groups. Narcotin OCH3 I c •\ HC C-OCHs I II HC CCO \/ c I HC— I CH3OC CH •\/\ /O— C C N-CH 3 H 2 C<( I I I x O— C C CH 2 c c H H 2 Narcotin occurs in opium in varying amounts averaging about 5 per cent, and is one of the bases of this group, which may often prove of interest to the drug analyst. It is a weak base and probably exists in ALKALOIDS DERIVED FROM ISOQUINOLIN 199 the free state in the drug, from which it may be removed by simple extrac- tion with ether. De-narcotized opium is a well-known article of commerce. Narcotin resembles papaverin and narcein by being extracted from acid solutions by chloroform; with papaverin it may be separated from nar- cein by precipitation with sodium acetate, and subsequently separated from papaverin by precipitating the latter with potassium ferricyanide. It crystallizes from alcohol or ether in prisms melting 176°, insoluble in cold water and cold alkalies, slightly soluble in hot water and petroleum ether, somewhat soluble in alcohol and ether and readily soluble in chloro- form and benzol. Its neutral solutions are lsevorotatory and its acid solu- tions dextro. Narcotin is precipitated by the general alkaloidal reagents. A solu- tion of the alkaloid in dilute hydrochloric acid gives a yellow T precipitate with bromin which dissolves on boiling. If bromin water is gradually added and boiled a rose color is produced and destroyed by excess of bro- min. A solution of the alkaloid in very dilute hydrochloric acid gives a white precipitate with potassium thiocyanate. If narcotin is heated with water at 140° or with sulphuric acid or barium hydroxide, it adds a molecule of water and is decomposed into opianic acid and hydrocotarnine. The opianic acid can then be recognized by the colorations produced with phenolic bodies. The test may be per- formed according to Labat 1 by dissolving .1 gram of the alkaloid in 0.5 mil of 10 per cent sulphuric acid and gently heating, after the addition of 2 mils of a 2 per cent solution of potassium permanganate, until the pink color has disappeared. The liquid is then diluted with alcohol until the opianic acid is approximately 1 per cent, and the solution used for the tests. On mixing 0.1 mil of this solution with 2 mils of concentrated sulphuric acid and 0.1 mil of the phenolic solution the following reactions are obtained: with 5 per cent alcoholic solution of gallic acid, a blue color- ation rapidly appears changing to greenish brown; with a 5 per cent alco- holic solution of guaiacol or pyrocatechol gooseberry-red, changing to an intense blue when heated on the water-bath; with a-naphthol a goose- berry-red and with /3-naphthol a wine red. Hydrastin will, of course, give the same reactions as it also is converted to opianic acid under similar conditions. If 0.1 mil of an alcoholic solution of narcotin (1-100) is added to 2 mils of concentrated sulphuric acid, 0.1 mil of 5 per cent solution of gallic acid added and the tube heated in a water-bath, an intense emerald-green color is obtained, changing to bright blue. This reaction is also given by hydrastin and hydrastinin. Zinc and hydrochloric acid, or sodium amalgam, reduce narcotin to meconin and hydrocotarnin. 1 Bull. Soc. Chim., 1909, IV, 5, 743. 200 ALKALOIDAL DRUGS Narcotin dissolves in sulphuric acid, yielding a pale-yellow solution, pink on the edges, and a red color gradually develops. Nitric acid or sodium hypochlorite added to its solution in sulphuric acid produce a red or carmine, and ferric chloride a cherry red. It gives a deep yellow with concentrated nitric acid, a deep green with Froehde's reagent; a brick-red with vanadium-sulphuric acid; and a purple to slate, soon fad- ing, with formaldehyde -sulphuric acid. Ammonium persulphate in sul- phuric acid gives orange red. Narcotin salts are not very stable, and water is usually sufficient to effect their decomposition. The hydrochloride and sulphate give clear solutions even when considerably diluted, but on adding sodium acetate to a solution of the hydrochloride the base is precipitated. The picrate melts 141° C. Narcotin is converted to narcein by digesting for ten hours with excess of methyl iodide, removing the excess of the latter on the water-bath, dissolving the residue in alcohol and treating with chlorin water. A light-yellow precipitate is first formed, which soon dissolves; with excess of chlorin the precipitate is darker, and after standing a few hours becomes crystalline. The filtrate on evaporation yields a brownish gum, becom- ing crystalline narcotin methylchloride, which gives narcein by neutraliz- ing with sodium hydroxide and passing a current of steam. Gnoscopin This alkaloid has been shown by Perkin and Robinson x to be racemic narcotin. It may be prepared from narcotin by heating with acetic acid to 130°, or by boiling cotarnin and meconin with potassium carbonate in alcohol. It melts at 228-233°, is insoluble in water and alkalies, slightly soluble in alcohol, and readily soluble in chloroform and benzol. It dis- solves in sulphuric acid to a yellow solution, becoming red on the addition of nitric acid, the color being permanent. The picrate melts 200° C. Oxynarcotin This is a feeble base which occurs in crude narcotin. It is slightly / soluble in alcohol and hot water and insoluble in the ordinary alkaloidal solvents. Hydrocotarnin This alkaloid was found in opium by Hesse. It is formed by the decom- position of narcotin and crystallizes in prisms containing one-half mole- cule of water, melting at 55°. It is insoluble in water and alkalies but dissolves in organic solvents. It may be distilled with little decompo- 1 Proc. Chem. Soc, 1910, 26, 46, 131. ALKALOIDS DERIVED FROM ISOQUINOLIN 201 sition at about 100° C. It is a tertiary base and a derivative of methyl- tetrahydroquinolin. By the action of sulphuric acid it forms a conden- sation product, hydro dicotarnin, C24H28N2O6. Hydrocotarnin dissolves in concentrated sulphuric acid with a yellow color, changing to carmine, blue-violet, and violet on warming. Narcein OCH3 6 HC COCH3 I II HC C-COOH V c I CH30 9° C CH 2 /\/ ,CH 3 /O-C C N< H 2 C< | II IXJHa x OC C CH 2 c c H H 2 Narcein has apparently the weakest basic properties of the opium alkaloids and has distinct acid properties. It contains a carboxyl and a carbonyl group, forms definite compounds with potassium and sodium hydroxide and reacts with hydroxylamine and phenyl hydrazine. Narcein crystallizes from water or alcohol in prismatic needles con- taining 3 molecules of water, optically inactive, melting 170-171°. The water is all driven off on heating to 100° and the anhydrous base melts at 145°. As prepared commercially it is separated with difficulty from the acid radicle, even when precipitated in presence of free ammonia, and hence its melting-point is variable. It is slightly soluble in cold water and chloroform, readily soluble in hot water, alkalies, and alcohol, and insoluble in ether, benzol, and petroleum ether. It is partly removed from a cold acidulated solution by chloroform, but the extraction is not complete and it is carried along in the aqueous liquid through the shake- outs in alkaline solution until it is finally found in the alcohol-chloroform fraction with morphin. Narcein gives no precipitate with Mayer's reagent, mercuric chloride, or potassium ferrocyanide ; it is precipitated by gold and platinic chlo- rides, picric acid, tannin and by potassium bichromate on standing. With 202 ALKALOIDAL DRUGS iodin a brown precipitate is obtained, and on removing the excess of iodin by ammonia, the precipitate is found to be blue. Weak iodin solutions color narcein a dark blue; on dissolving in boiling water a color- less solution results from which violet or blue crystals separate on cooling. If iodin is strewn on a cold saturated solution of narcein, fine needle- like gray crystals form around the iodin. The picrate melts 127-128.5° and the platinochloride begins to darken at 190° and melts 198-199° C. Narcein forms crystalline salts with caustic alkalies by heating the base at 60-70° with a 33 per cent solution of the alkali. The alkaloid is regenerated when the salts are treated with acids or carbon dioxide. The color reactions of narcein are not especially characteristic; with sulphuric acid it gives a brown color, becoming yellow, green, and finally blue; Froehde's reagent gives greenish brown, vanadium sulphuric acid reddish brown; formaldehyde-sulphuric acid, brown, greenish on edges; nitric acid a fading yellow. When treated with sulphuric acid contain- ing a trace of tannin a green color is produced, the same reaction being given by narcotin and hydrastin. When warmed with sulphuric acid containing a trace of resorcinol, a crimson to cherry-red color is produced, becoming blood-red on cooling and gradually fading to orange. Ammon- ium persulphate in sulphuric acid gives violet changing to blood-red and yellow. A solution of narcein in very dilute hydrochloric acid gives a precipi- tate of white hair-like crystals becoming blue on standing, with a few drops of potassium-zinc iodide solution. 0.01 gram narcein in 5 mils of very dilute hydrochloric acid gives an orange-red coloration with 1 mil of chlorine water, followed by an excess of ammonia. Thebain under similar conditions gives a reddish-brown color. Ethyl narcein hydrochloride is known as narcyl, and occurs in pris- matic needles soluble in water and alcohol. Apomorphin This body was mentioned under the description of morphin as being one of its alteration products, differing from the parent substance by the elements of one molecule of w T ater, and being the characteristic substance produced in performing Pellagri's test. It occurs on the market as the crystalline hydrochloride and is generally employed as an emetic, expector- ant, or hypnotic in the form of syrups and hypodermatic tablets. It is a substance which is very prone to decompose and furthermore often con- tains impurities. It is seldom administered with other drugs. The base itself, when freshly precipitated, is white and amorphous, but it soon turns green on exposure to light and air. It is readily soluble ALKALOIDS DERIVED FROM ISOQUINOLIN 203 in alcohol, ether, chloroform, and benzol; the solutions taking various shades of green, magenta, or violet. In the regular scheme of analysis, apomorphin will first make itself apparent when ammonia is added to the acid solution preparatory to shaking out with petroleum ether; at this juncture a green color appears, becoming more or less deep and intense, depending on the quantity of the base present; on shaking out with ether the solvent will acquire a magenta shade, due to the removal of some of the oxidation products. The same reaction will be obtained on shaking with either chloroform or benzol, the shades often varying from magenta to violet or purple. These reactions are about all that is necessary to diagnose the pres- ence of apomorphin. Pilocarpin gives oxidation products which dis- solve in volatile solvents with bluish shades, but these oxidation products require for their production the assistance of some agent stronger than atmospheric oxygen, and hence are not formed in the ordinary procedure of analysis. The color reactions given by apomorphin residues with the oxidizing agents used in the detection of the opium alkaloids are as follows : nitric acid gives at first a violet color soon changing to mahogany brown and later to orange; Froehde's reagent gives a deep blue, fading to slaty violet; vanadium-sulphuric acid a deep blue; formaldehyde-sulphuric acid a purple with a greenish-blue cast underneath, finally deep blue- black; bichromate and sulphuric acid deep green. Apomorphin solutions, even when extremely dilute, give a green color- ation when rendered faintly alkaline with potassium bicarbonaate. If a dilute solution is made alkaline with sodium hydroxide, a few drops of chloroform added and the mixture shaken, the chloroform will settle out with a blue color and the aqueous layer will be violet. With ferric chloride a rose-red color is obtained changing to violet and black. With a dilute solution of ferrous sulphate the solution becomes blue and then black, returning to blue on adding alcohol. Iodic acid gives the same color- ation as is obtained with a solution of morphin. The hydrochloride occurs in the amorphous state and in minute crys- tals, the latter form being the purest. The crystals should be kept tightly corked and away from the light and a freshly made solution should be colorless or with but a slight green color. Some commercial hydrochlo- rides have been found to contain varying amounts of beta-chloromor- phide which may be detected by dissolving 0.1 gram in 10 mils of water, adding 5 mils of saturated sodium-carbonate solution, shaking with ether, washing the ether with 3 portions of water, and then evaporating the ether. The ether residue is then treated with 5 mils of concentrated nitric acid and .02 gram silver nitrate, and after standing a short time is heated on the steam-bath, water being added from time to time to keep \ 204 ALKALOIDAL DRUGS up the volume. If any appreciable amount of silver chloride is seen, the presence of the impurity is indicated. If potassium ferricyanide is added to a dilute solution of apomorphin followed by benzol and shaking, the solvent will be colored an amethyst violet changing to violet red on shaking with sodium hydroxide. The free base precipitated from hydrochloric acid solution by sodium bicarbonate, melts 160-170° with decomposition. The melting-point constant is not very reliable, because of the difficulty of obtaining a pure product free from oxidation products. Apomorphin methyl bromide, C17H17NO2 • CHsBr, known as eupor- phin, occurs in the form of colorless needles or scales, melting 180° C, and readily soluble in water and alcohol. It is used for the same pur- poses as apomorphin and its solutions seem to be more stable. Apocodein Apocodein, which is prepared from codein in an analogous way to apomorphin from morphin, is probably an indefinite mixture of basic derivatives of codein and morphin. It has a limited use as the hydro- chloride, which is a yellowish to greenish-gray hygroscopic powder. The base gives a blood-red color with nitric acid; with Froehde's reagent a blue changing to brown and green to a purplish olive; with formalde- hyde-sulphuric acid a brown to brownish purple, then black. Eucodein Codein methyl bromide occurs in colorless crystals, melting at 261°, readily soluble in water and slightly in alcohol. It is soluble in sulphuric acid with evolution of hydrobromic acid, gives a brown-violet to blackish- green color with formaldehyde-sulphuric acid, and a brown to dirty green with Froehde's reagent. Heroin, Diacetyl morphin, C21H23NO5 Heroin is probably the most widely used artificial derivative of mor- phin and is readily prepared from its parent base by heating with acetyl chloride or acetic anhydride. The diacetyl morphin is liberated by a mild alkali and extracted in the cold and may be crystallized out of alcohol. The free base melts 171-172°, is almost insoluble in water and petroleum ether, somewhat soluble in alcohol and ether, and readily soluble in chloro- form and benzol. When heated in solution it is prone to decompose and in analytical work the manipulations must be done in the presence of ice. This factor must be considered in quantitative work when one is working with a product in which a stated amount of heroin has been declared. If a smaller quantity than that declared is found, it must not ALKALOIDS DERIVED FROM ISOQUINOLIN 205 be considered conclusive that the proper quantity was not originally present, but a further examination must be made for morphin. It differs from morphin in being completely and easily removed from alkaline solutions by chloroform and in giving a pale-yellow color grad- ally turning green with nitric acid. It gives a brilliant crimson-purple color, soon fading, with Froehde's reagent, a permanent crimson-purple with formaldehyde-sulphuric acid; and a pale violet soon fading with vanadium-sulphuric acid. With hexametlrylene tetramine in sulphuric acid a golden-yellow color is obtained, changing to saffron and finally to blue. On heating with sulphuric acid and alcohol, ethyl acetate is formed, which becomes apparent by its odor. Its neutral solutions do not liberate iodin from iodic acid, nor give a blue color with ferric chloride. It is precipitated by the ordinary alka- loidal reagents. The picrate, recrystallized from 50 per cent alcohol, melts 200-205° C. Heroin is a cough sedative and antispasmodic, and is used in remedies for consumption, asthma, bronchitis, and similar ailments. The hydro- chloride is a white crystalline powder readily soluble in water and alcohol. Ethyl morphin, Ci 7 His(C 2 H 3 )N0 3 Ethyl morphin, the base of Dionin, which is its hydrochloride, is closely related to codein and resembles the latter in its properties. It is liberated from its acid solution by alkalies and may be completely removed from alkaline solution by ether and chloroform, but it is insolu- ble in petroleum ether. When heated to 110-115° it decomposes with- out melting. It gives a yellow color with nitric acid; a green to deep green and eventually a blue color with Froehde's reagent differing to some extent from codein in the first phase of this reaction ; purple with formal- dehyde-sulphuric acid; and green with vanadium-sulphuric acid. It is less soluble in ammonia than codein, a 10 per cent solution of the hydro- chloride of the latter gives a precipitate on the addition of a few drops of ammonia soluble on the addition of 1 mil excess, while with a 10 per cent solution of dionin, the separated base does not go into solution until 5 mils of ammonia are added, and soon separates again on standing. The hydrochloride, which is the form in which it is always found commercially, is a white crystalline powder, readily soluble in water and alcohol. A solution of the substance in water when added to ferric chlo- ride containing a trace of potassium ferricyanide develops a blue-green color. 206 ALKALOIDAL DRUGS Benzyl Morphin, C 17 Hi 8 N0 2 OC 6 H 5 CH2 Benzyl morphin is the base of Peronin, the commercial name of its hydrochloride. It is liberated from its acid solutions by alkalies and under these conditions may be shaken out partly by petroleum ether and readily by ether. The residue gives a yellow color with nitric acid, a brown, violet, brownish green to slate with Froehde's reagent; an olive brown with vanadium-sulphuric acid; and a crimson, with a purplish shade gradually appearing with formaldehyde-sulphuric acid. Meconic Acid O c /\ HC COH II II COOH— C C— COOH \y o From an analytical standpoint, meconic acid is the most important of the non-basic constituents of opium for its identity serves to substanti- ate the presence of the drug. In the ordinary scheme of qualitative analysis, the acid will appear in the ether shake-out from acid solution and will be indicated by the deep-red color it gives when its aqueous solution is treated with ferric chloride. The deep-red color is not dis- pelled on warming with hydrochloric acid nor changed by gold chloride, it is, however, bleached by stannous chloride and restored by potassium nitrite. It may be purified by precipitating in aqueous solution with lead acetate, washing the precipitate, subjecting the latter to a stream of hydrogen sulphide in the presence of water and after filtering from the lead sulphide the pure acid may be shaken out with ether. Meconic acid crystallizes in micaceous scales or rhombic prisms with 3 molecules of water. It loses its water of crystallization at 100° and at 120° is converted to comenic acid, C6H4O5, with loss of CO2, and on further heating yields pyromeconic acid with a further loss of CO2. /OH /OH /OH C 5 H0 2 ^-COOH C 5 H0 2 f-H C 5 H0 2 ^-H \COOH \COOH NB Meconic Acid Comenic Acid Pyromeconic Acid Comenic acid is insoluble in cold water and absolute alcohol and spar- ingly soluble in boiling water. Both this acid and pyromeconic acid give red colorations with ferric chloride. Meconic acid is -fairly soluble in cold and readily in hot water, and is rendered less soluble by the presence of hydrochloric acid. It is readily ALKALOIDS DERIVED FROM ISOQUINOLIN 207 soluble in alcohol and ether, and insoluble in chloroform. The solid acid gives a characteristic purple to deep blue color, gradually fading, with vanadium sulphuric acid. The microscopic appearance of its crystals from aqueous solution and of the precipitates with barium chloride, cal- cium chloride and potassium ferrocyanide are characteristic. Meconin is often an impurity in the meconic acid extraction from opium and may be separated and identified by shaking the solution with benzol or chloroform which removes the meconin leaving the meconic acid in solution. On evaporating the solvent the meconin residue may be treated with concentrated sulphuric acid which will give a pale yellow color gradually changing to pale violet on standing. On adding a frag- ment of potassium nitrate to a solution of meconin in concentrated sul- phuric acid, a yellow coloration is obtained, rapidly changing to scarlet. Meconin is a neutral substance, somewhat soluble in boiling water, and ether, and dissolving readily in alcohol, chloroform, and benzol. It crystallizes in prisms which melt under water at 77°. The crystals melt in the air at 102-103°. It is a reduction product of opianic acid and is produced when narcotin is treated with zinc and hydrochloric acid. Its formula is CH 2 — O K l -CO I— OCH3 OCH3 Qualitative and Quantitative Determination of the Opium Bases and Their Derivatives. — The alkaloids of this group are not difficult to detect and in the regular scheme of separation will appear in the several frac- tions where their identity will be indicated and from that point can be substantiated by applying the various reactions described for the specific individuals. As we have indicated in the preceding paragraphs, the num- ber of individuals of interest from an analytical standpoint is limited to morphin, codein, narcotin, papaverin, thebain, narcein, and meconic acid among the naturally occurring substances; and to heroin, ethylmorphin, and apomorphin in the artificial group. In quantitative work the analyst will seldom be called upon to determine other than morphin, codein, heroin, and ethylmorphin. Morphin is, in one way, about the easiest alkaloid to separate from other bases as it is not removed from its solu- tion in caustic alkalies by immiscible solvents, and from ammoniacal solutions with difficulty only with chloroform, and not with ether. In qualitative work, an alcoholic extract of the dry sample or of an 208 ALKALOIDAL DRUGS evaporated liquid product should be concentrated to drive off the alcohol and then taken up with water and dilute sulphuric acid and subjected to the shaking-out scheme with immiscible solvents. Petroleum ether will remove nothing of interest of this group; ether will take out meconic acid, meconin, a little narcotin, and narcyl; chloroform will extract nar- cotin, papaverin, narcyl, and some of the narcein. The solution should then be rendered slightly alkaline with dilute potassium or sodium hydrox- ide and any green color noted which will at once indicate apomorphin; petroleum ether will take out some of the peronin if this substance is present; ether will remove apomorphin partly (both solvent and alkaline solution becoming colored, due to oxidation products), codein, ethyl- morphin, thebain, apocodein, and laudanosin will be completely extracted, heroin, papaverin, and laudanin in part; following this shake-out chloro- form will remove the rest of the apomorphin, heroin, laudanin, protopin, and a further quantity of papaverin if this has not been entirely removed in the previous fractions; morphin and narcein may then be shaken out by adding a little ammonium chloride and shaking out with chloroform- alcohol 2-1. After evaporating the solvents in the separate fractions, portions of each residue should be examined in the following order: the ether frac- tion from acid solution will give evidence of meconic acid by the ferric chloride and vanadium-sulphuric acid test and this body can be separated from meconin and the latter detected as described under meconic acid; narcotin will be indicated by the tests with Froehde's reagent, vanadium- sulphuric acid, and formaldehyde-sulphuric acid. The chloroform resi- due from acid solution will give indication of narcein, narcotin, and papav- erin by the color tests with sulphuric acid, Froehde's reagent, vanadium- sulphuric acid, formaldehyde-sulphuric acid, and nitric acid. In the petroleum ether residue from the alkaline solution peronin will be indi- cated by the tests with formaldehyde-sulphuric acid and Froehde's reagent. In the next residue, ether from alkaline solution, the greatest variety may occur; nitric acid will give green with heroin, yellow with codein, and violet to deep brown and finally orange with apomorphin; formaldehyde- sulphuric acid will give shades of reddish purple and violet with codein, heroin, ethylmorphin, peronin, papaverin, apomorphin, and apocodein and red-brown with thebain; Froehde's reagent will give blue with codein, green to blue with ethylmorphin, purple to blue with papaverin, crimson purple with heroin, blue to violet fading to brownish green and finally slate with peronin, and red-brown with thebain. The chloroform frac- tion in the main serves to substantiate the results obtained with the ether fraction and in the chloroform-alcohol fraction morphin will be indicated by its reactions with nitric acid, Froehde's reagent, and formaldehyde- sulphuric acid : narcein with sulphuric acid alone gives a deep-brown color ALKALOIDS DERIVED FROM ISOQUINOLIN 209 at the moment of solution, this changes to yellow, then green, and finally blue. If one finds meconic acid, morphin and some of its associated alkaloids, he may feel reasonably certain that he is dealing with a product contain- ing opium. Kerbosch 1 describes a method of separating the opium alkaloids from each other. The mixed bases are extracted with a mixture of chloro- form-alcohol 4-1 containing a trace of ammonia, the solvent evaporated and the residue dissolved in N/10 hydrochloric acid, narcotin is then parti- ally precipitated by sodium acetate; sulphuric acid is added and papaverin thrown out by caesium cadmium iodide, the crystals being identified microscopically; narcein is then precipitated by sodium acetate and iden- tified by the blue coloration imparted with iodin; thebain is also precipi- tated in presence of sodium acetate. The solution is then thoroughly shaken out with chloroform, ammonia added, the codein removed by benzol and morphin by chloroform-ether mixture, both being identified by the characteristic forms of their csesium-cadmium-iodide compounds. Plugge has also given a scheme for separating the opium alkaloids which deserves consideration. A solution of the free alkaloids is treated with sodium acetate which precipitates the Earcotin and papaverin. The filtrate is set aside and the precipitate dissolved in the least quantity of hy- drochloric acid and diluted with water to a f-per cent solution, from which the papaverin is precipitated by potassium ferricyanide, and after filter- ing and adding ammonia, the narcotin is shaken out with chloroform. The filtrate from the sodium acetate precipitation is concentrated and the narcein will crystallize out; it is filtered, concentrated sodium salicy- late added and allowed to stand twenty-four hours for the thebain salicy- late to crystallize. It is then filtered, acidulated with hydrochloric acid, and the excess of salicylic acid and any traces of thebain and narcein removed with chloroform. The solution is then concentrated, potassium sulphocyanide added, which precipitates the codein, it is filtered, ammonia added, any residual codein removed by ether, then acidified, heated to 60° C, ammonia added, and the morphin shaken out with chloroform- alcohol mixture. When it is necessary to look for these alkaloids in lozenges or medica^ ments containing large quantities of gum, the sample should be dissolved in water, employing as small a quantity as possible, a little acid added and the solution poured into about ten times its volume of alcohol. This will precipitate the gum which soon coagulates and settles to the bottom or collects on the sides of the container. The solution contains the alka- loids and it may be filtered, neutralized and the alcohol evaporated, the rest of the separation being conducted as usual. 1 Arch. Pharm., 248, 1910, 536. 210 ALKALOID AL DRUGS Opium alkaloids may be detected without difficulty when they occur in mixtures containing at the same time the bases of ipecac, Hyoscyamus, and cinchona, though the reverse is not accomplished with the same facility for the brilliant color tests of the opium bases obscure the reac- tions of the other substances. Atropin is readily identified when it occurs with morphin alone, for it is removed from alkaline solution by ether, leaving the morphin still in solution. The same condition prevails if strychnin, cocain, hydrastin, or Sanguinaria bases are present, they are all removed from an alkaline (caustic) solution by immiscible solvents, leaving the morphin. On sub- sequently adding ammonium chloride and shaking out with chloroform- alcohol mixture the morphin will be extracted. Acetanilid mixtures give up their acetanilid to chloroform in acid solution and caffein may be separated in like manner. Codein may be identified when in mixtures with acetanilid or caffein by first shaking out these two substances from acid solution with chloro- form. Colchicin may also be removed under the same conditions. Anti- pyrin cannot be satisfactorily separated from codein, but it may be identi- fied when present, for it is partly removed from acid solution while codein is not, and codein gives certain reactions to which antipyrin does not respond, Apomorphin, heroin, ethylmorphin, and benzylmorphin will probably seldom if ever be found in admixtures with other bases. Much attention has been given to the determination of morphin in opium products and many methods for accomplishing this purpose have appeared during the last ten years. Probably the greatest advance in evolving accurate, simple, and rapid methods has been attained at the Bureau of Chemistry of the U. S. Department of Agriculture and in 1909 Eaton * published his method for the estimation of morphin in opium, paregoric, laudanum, and cough mixtures. The writer has tried the method on many occasions and has found it most easy of application and accurate in its results, but like many other procedures in alkaloidal anal- ysis it should not be attempted by a novice until he has familiarized him- self with all its details. Following this work Buchbinder made an exhaust- ive study along the Eaton line of research and has communicated to me a modification of Eaton's method which bids fair to settle the many difficulties which have attended this important subject. Eaton's method for the determination of morphin in opium was given in full on page 57. The adaptation of this procedure to opium prepa- rations is given at this point. i Bur. Chem. U. S. Dept. Agri. Bull. 137, p. 188. ALKALOIDS DERIVED FROM ISOQUINOLIN 211 ESTIMATION OF MORPHIN IN PAREGORIC Evaporate 100 mils on the water-bath to a volume not exceeding 15 mils. Transfer to a separatory funnel, using no more than 2 or 3 mils of water at a time for the rinsings and no more than 15 mils in all. Shake out twice with 25 mils of ether, collect the ether and wash with 5 mils of water. Reject the ether and add the wash water to the main aqueous por- tion. To the latter add 30 mils of lime water, mix thoroughly, filter into a separatory funnel (No. 1), and wash with several small portions of lime water, using no more than 20 mils in all. Proceed as in the method given for opium, beginning with the fourth sentence: " Shake out seven times with washed chloroform," etc. ESTIMATION OF MORPHIN IN SYRUP PREPARATIONS Take a convenient volume to yield between 30 and 75 milligrams of morphin. Make acid, then ammoniacal, and extract to complete exhaus- tion with a mixture of chloroform and alcohol, using large proportions of alcohol than that given above, if necessary to clear emulsions. In all cases do not consider the morphin exhausted until an actual test with 5 mils of the last shake-out, carried out as indicated above in the method for opium (Mayer's reagent), shows it to be free from alkaloid. Do not test before at least seven shake-outs (not including the last shake-out on a portion of which the test is to be carried out) have been made. Evapo- rate (on the water-bath) the combined chloroform-alcohol to dryness. Take up in 30 mils of lime water, filter into a separatoiy funnel, rinse, and wash several times with small portions of lime water, using about 20 mils in all. Proceed as in the method for opium, beginning with the fourth sen- tence: " Shake out seven times with washed chloroform," etc. Mr. Buchbinder's method for the determination of morphin as com- municated to me is quoted herewith in full. POWDERED OPIUM Reagents : Sodium hydroxide, 10 per cent. Common salt. Alkaline salt solution, made by saturating a 2 to 2J per cent sodium hydroxide solution with common salt and filtering. Barium chloride, a saturated solution. Concentrated hydrochloric acid. Concentrated ammonia. Alcohol. Chloroform. Methyl red (.2 per cent alcoholic solution), or Cochineal. (IT. S. P.) 212 ALKALOIDAL DRUGS Digest 2 grams of powdered opium in 50 mils of water in a loosely stoppered Erlenmeyer for twenty minutes at a temperature between 90 to 100° C. While still hot add 20 mils of 10 per cent sodium hydroxide, and rotate gently. Allow to cool somewhat, stopper the Erlenmeyer and shake, not too violently, during ten minutes. Transfer the contents of the Erlenmeyer into a 200-mil graduated flask containing 18 to 20 grams of powdered common salt. Stopper and shake gently until the salt is dissolved. Rinse the Erlenmeyer and the stopper with several portions of alkaline salt solution, adding the rinsings to the graduated flask, and dilute with the same solution to a total volume of about 175 mils. Rotate so as to mix. Add 15 mils of a saturated solution of barium chloride. Reduce the froth by the addition of a little alcohol and make up to volume with alkaline salt solution. Stopper, shake thoroughly, then filter through a large, dry, fluted paper, if not clear, refilter. By means of a pipette remove 100 mils of the filtrate, corresponding to half the weight of the sample taken and introduce into a separatory funnel No. 1. Add concentrated hydrochloric acid in portions — towards the end not over J mil at a time — until acid to litmus; then add 4 mils in excess. Add concentrated ammonia in portions, — towards the end not over 4 drops at a time — until alkaline; then add 1 mil in excess. Add 10 mils of alcohol and shake out six times with chloroform, 30, 20, 20, 15, 15, and 15 mils respectively, filtering each successive shake-out through a piece of cotton wetted with chloroform and wedged in the neck of a small funnel, into a separatory funnel No. 2. Discard the liquid in separa- tory funnel No. 1. To funnel No. 2 add 15 mils of alkaline salt solution, shake, then with- draw the chloroform layer into a separatory funnel No. 3. To funnel No. 3 add 5 mils of alkaline salt solution, shake, withdraw the chloroform layer into a beaker and add the alkaline salt layer to funnel No. 2. Return the chloroform to funnel No. 3, shake with a fresh portion of 5 mils alka- line salt solution, reject the chloroform layer and keep the alkaline salt layer for later use. Shake out the alkaline salt solution in funnel No. 2 twice with 25 mils of chloroform each time, collecting the chloroform in a separa- tory funnel No. 3. Shake funnel No. 3. Reject the chloroform layer and add the alkaline salt layer to the main alkaline salt solution in funnel No. 2. To funnel No. 2 add concentrated hydrochloric acid carefully, reach- ing acidity within 2 or 3 drops; then add 1 mil in excess. Add concen- trated ammonia carefully, reaching alkalinity within 1 or 2 drops; then add 5 drops in excess. Add 3 mils of water and 4 mils of alcohol. Shake out five times with chloroform, 30, 10, 10, 5, and 5 mils respectively, filtering each successive shake-out through cotton wetted with chloro- form into a beaker. ALKALOIDS DERIVED FROM ISOQUINOLIN 213 Evaporate the chloroform on the water-bath to dryness. Add 10 to 20 mils of neutral alcohol and heat to dissolve. Add 3 drops of methyl red or 5 drops of cochineal. Add N/50 sulphuric acid until about 2 to 5 mils in excess. At this stage look out for any undissolved specks; heat again if necessaiy. If cochineal is used the alcohol should be almost entirely evaporated . If methyl red is used either evaporate the alcohol or else add water until a pure red tint is obtained. Titrate back with N/50 or N/100 sodium or potassium hydroxid which has been ascertained to be sufficiently free from carbonates to give a sharp end point with the indicator used. One mil of N/50 acid corresponds to 6 mgms. of crystallized morphin. If more than 150 mgms. are indicated, repeat the analysis with a smaller quantity of the sample. GUM OPIUM Weigh out about 2 grams of gum opium in a beaker. Add 50 mils of water, cover with a watch glass and digest at a temperature between 90 to 100° until thoroughly disintegrated. Use a glass rod to mash particles. Transfer to an Erlenmeyer and while still hot add several portions of 10 per cent sodium hydroxide, using those same portions first to rinse the beaker, using in all about 20 mils. Allow to cool somewhat, stopper the Erlenmeyer and shake not too violently during ten minutes. Trans- fer the contents of the Erlenmeyer into a 200-mil graduated flask con- taining 18 to 20 grams of powdered common salt. Stopper and shake gently until the salt is dissolved. Rinse the Erlenmeyer and the stopper and also the beaker in which the digestion of the opium was made, with several portions of alkaline salt solution, adding the rinsings to the gradu- ated flask, and dilute with the same solution to about 175 mils. Proceed as directed for opium, beginning with the seventh sentence in the first paragraph: " Rotate so as to mix." LAUDANUM Into a beaker to which has been added 40 mils of water and 20 mils of 10 per cent sodium hydroxide, introduce from a pipette or a burette 20 mils of laudanum. Stir with a glass rod, then transfer into a 200-mil graduated flask containing 18 to 20 grams of powdered common salt. Stopper and shake gently until the salt is dissolved. Rinse the beaker with several portions of alkaline salt solution, adding the rinsings to the graduated flask, and dilute with the same solution to a volume of about 175 mils. v Proceed as directed for powdered opium, beginning with the seventh sentence in the first paragraph: " Rotate so as to mix." 214 ALKALOIDAL DRUGS PAREGORIC Evaporate 200 mils of the sample to a volume of 50 or 60 mils. Trans- fer to a separatory funnel, rinsing the vessel in which the evaporation was made with several small portions of water, adding the rinsings to the separatory funnel. Shake out three times, 20 mils each time, with ether, collecting the ether in another separatory funnel. Wash the ether with 5 mils of water. Reject the ether and add the wash water to the main aqueous layer. Withdraw the latter into a beaker, rinse the funnel with several small portions of water, adding the rinsings to the beaker. Heat the beaker on the water-bath until all the ether is expelled. Add 20 mils of 10 per cent sodium hydroxid. Rotate so as to mix. Transfer into a 200-mil graduated flask containing 1 gram of powdered common salt for every 3 mils of the solution. Add 15 mils of water. Stopper the flask and shake gently until the salt is dissolved. Rinse the beaker with several portions of alkaline salt solution, adding the rinsings to the graduated flask, and dilute with the same solution to about 175 mils. Proceed as directed for powdered opium, beginning the seventh sentence in the first paragraph; " Rotate so as to mix." THE DETERMINATION OF MORPHIN IN TABLET TRITURATES. DIRECT EXTRACTION METHOD, H. E. BUCHBINDER Reagents : Sodium chloride — finely powdered. Ammonium chloride. 95 per cent alcohol. Cone, ammonia — 25 to 28 per cent. Chloroform. Neutral 95 per cent alcohol for dissolving the alkaloidal residue; 10 mils diluted with 20 mils of water to which has been added 3 drops of methyl red, should not require more then one drop of N/50 alkali to turn yellow. Methyl Red — a 0.2 per cent alcoholic solution. Standard N/50 sulphuric acid. Standard N/50 or N/100 NaOH or KOH which is sufficiently free from carbonates to give a sharp end point with three drops of methyl red when used to titrate 5 mils of N/50 acid diluted with 20 mils of water. Sample 600 mg. Take a weighed amount of the powdered sample to yield not more than 140 mgms. of " crystallized " morphin. Brush into a 50-mil beaker. Fill a 50-mil measuring cylinder up to the 50 mark with water. Add 30 mils of the water in the cylinder to the beaker. Stir with a glass rod, ALKALOIDS DERIVED FROM ISOQUINOLIN 215 breaking up any lumpy particles, until the powder is dissolved as com- pletely as possible (there may be left a small amount of insoluble material). Transfer to a separatory funnel containing 14 to 14§ grams of finely pow- dered sodium chloride and 1 gram (weigh within 100 mgms.) of ammo- nium chloride. Use the remaining 20 mils of water in the cylinder, in several small portions, to rinse the beaker, draining completely both the cylinder and the beaker. Stopper the funnel and shake till the salt has dissolved. Add 10 mils of 95 per cent alcohol. From a burette or a pipette add 0.5 mil of concentrated ammonia. Immediately after the addition of the ammonia add 30 mils of chloro- form containing 5 per cent alcohol, stopper, and shake gently for one minute. When the layers have separated and there is no emulsion, draw off the chloroform, filtering through a small filter paper wetted with chloro- form, or through a small plug of cotton carefully wedged in the neck of a funnel and wetted with chloroform, into a beaker or flask. Repeat this process five more times with 15, 15, 10, 10, and 10 mils of chloroform respectively. In case of even slight emulsions the extraction of the alka- loid should be performed as follows. Draw off the chloroform layer together with the emulsified part into a second separatory funnel, and shake gently. In most cases the emulsion will dissappear or be greatly reduced. Draw off the chloroform, filtering into the beaker or flask. Treat the next shake-out in the same manner by drawing off both the chloroform and any emulsified part into the second separatory funnel, shaking and filtering. Repeat this process with each successive shake- out. In the case of emulsions not amenable to this treatment, the method as outlined cannot be used without suitable modifications. Evaporate or distill off the chloroform on the water-bath. Dissolve the residue by warming with about 10 mils of neutral alcohol, add 3 drops of methyl red, run in standard N/50 sulphuric acid until the indicator has turned red, then add a few mils in excess. Heat on the water-bath to insure the complete solution of the alkaloid. After cooling, titrate back with N/50 or N/100 alkali. One mil of N/50 acid corresponds to 6.00 mgms. of morphin IH2O (" crystallized "), and to 7.53 mgms. of morphin sulphate 5H 2 0. DETERMINATION OF SMALL QUANTITIES OF MORPHIN Small quantities of morphin present in opium in Chinese pills may be estimated very closely by converting it to heroin and weighing as such according to a procedure communicated to the author by Dr. H. A. Seil. The pills are exhausted with dilute acetic acid and if much gum is pres- ent the solution is poured into a considerable excess of alcohol and allowed to stand until the gum coagulates, after which it is filtered and the alcohol evaporated. The concentrated solution is transferred to a flask, 1-2 grams 216 ALKALOIDAL DRUGS anhydrous sodium acetate added, boiled with an excess of acetic anhydride, cooled, and transferred to a separator with water and in 'the presence of cracked ice. The acid solution is shaken two or three times with chloro- form, separating the solvent and washing it with water, returning the latter to the acid mixture, and then the acid is neutralized with sodium bicarbonate, a slight excess being added. The heroin is then shaken out with ether and weighed after evaporating the solvent. COLORIMETRIC ESTIMATION OF MORPHIN AND CODEIN The estimation of small amounts of morphin or codein may be effected by the following colorimetric method of Carlinfanti, 1 a Wolff colorimeter being employed. The alkaloid is first isolated from the bulk of the sample by proper solvents, brought into solution with hydrochloric acid, and made up to a definite volume. In the case of morphin 1 to 5 mils are evaporated to dryness and cooled. The residue is dissolved in 5 mils of concentrated sulphuric acid, and the liquid introduced into a tube holding about 50 mils, fitted with a ground stopper; the dish is washed twice with 3 mils of concentrated acid, the washings added to the tube, which is then closed and immersed for fifteen minutes in a boiling water-bath. To the cooled tube is added 10 mils of a mixture of 100 mils of concen- trated sulphuric acid and two drops of nitric acid (sp. gr. 1.4); on shak- ing, the characteristic blood-red color appears. The solution is then intro- duced into the cylinder of the colorimeter. An aliquot of a 0.5 per cent solution of morphin hydrochloride (1 mil or more) is evaporated and the residue treated in the same way. The solutions in the tube are then matched by the addition of small quantities of concentrated sulphuric acid. In the case of codein the solutions of the sample and the standard are evaporated to about 1 mil by evaporation on a water-bath at 70-75°; 15 to 20 mils of monohydrated sulphuric acid are added cautiously so that the mixture is not heated. The liquid is then introduced into a 50-mil flask, the dish washed with 3 portions of monohydrated sulphuric acid, 5 mils each, and treated with 10 mils of a solution of monohydrated sulphuric acid 100 mils and 10 per cent ferric chloride 2 mils. After being shaken, the flasks are immersed for fifteen minutes in a water-bath at 80° C, the cooled solutions, which have assumed blue colorations, being introduced into cylinders of the colorimeter as before. ESTIMATION OF CODEIN IN OPIUM Dr. Caspari 2 has devised the following method for the estimation of codein in opium. Fifty grams of the sample are macerated with 500 1 Boll. Chim. Farm., 1915, 54, 321. 2 Pharm. Review, 1904, 348. ALKALOIDS DERIVED FROM ISOQUINOLIN 217 mils of water for twelve hours with frequent agitation, filtered, and washed until the filtrate measures 750 mils, the residue is returned to the flask and shaken for fifteen minutes with 250 mils water, filtered and washed until this second filtrate measures 850 mils. The two filtrates are then combined, evaporated to 250 mils, treated with 5 grams barium acetate to precipitate the meconic acid and part of the resin, diluted to 700 mils, filtered, concentrated, and again precipitated with barium acetate. After filtering and washing the filtrate, a slight excess of 10 per cent sodium hydroxide is added which precipitates thebain, papaverin, and narcotin, leaving the codein, morphin, and narcein in solution; the mixture is fil- tered and washed after standing a short time. Concentrated hydro- chloric acid is then added to neutralize the alkali, followed by an excess of 2 per cent ammonia water, and the flask allowed to stand for several hours and then filtered from the precipitated morphin, which is washed and the filtrate concentrated and the treatment repeated to remove addi- tional morphin. The filtrate is rendered slightly acid with hydrochloric acid and concentrated to 75 mils, ammonia added in excess and the codein extracted with benzol. The solvent is then evaporated and the codein either weighed or titrated. A. E. Andrews * claims that the morphin carries down some of the codein in the above method and recommends the following procedure. Twelve grams of dry opium are exhausted with successive small quan- tities of water and the filtered solution adjusted to 100 mils; 20 mils of 20 per cent lead-acetate solution added and after standing overnight, filtered rapidly on a Buchner filter; 100 mils of the filtrate, represent- ing 10 grams opium, are subjected to a stream of hydrogen sulphide to remove the lead, filtered, the lead sulphide washed and the washings concentrated before adding to the main filtrate, from which the hydrogen sulphide is expelled by a current of air. The solution which should amount to no more than 130 mils is well shaken with 20 mils of a 20 per cent solu- tion sodium salicylate and filtered from the resinous precipitate; a few crystals of thebain salicylate are added, the liquid stirred to facilitate the separation of any thebain as salicylate, and after standing overnight filtered through the same filter and the treatment repeated until no further separation occurs. The filter is then washed, the filtrate concentrated to 10-15 mils and while still warm, transferred to a separator, the rinsings being placed in a second separator. The solution is shaken three times with ether, the solvent each tune being used for extracting the rinsings, and the aqueous solutions are then united and treated with 10 mils of 20 per cent sodium hydroxide and extracted four times with ether. The ether extracts are washed separately with two portions of water, united, dried with anhydrous sodium sulphate and distilled until only a few mils 1 Analyst, 1911,489. 218 . ALKALOIDAL DRUGS are left when the codein crystallizes out. The alkaloid is dried in vacuo weighed and titrated. CODEIN AND MORPHIN IN ADMIXTURE WITH CAFFEIN, ACETANILID, ACETPHENETIDIN AND QUININ Dr. W. 0. Emery 1 gives details of a method for the determination of codein, caffein, and acetphenetidin in pills and tablets of the cold and headache mixture type. Weigh out about 0.3500 gram of powdered material (if in pill or tablet form at least ten of these should be reduced to powder), transfer to a separatoiy funnel by means of 10 mils very dilute sulphuric acid (or suf- ficient to render the solution decidedly acid after neutralization of any carbonate that may be present), extract by means of vigorous shaking with 50 mils of chloroform. After clearing, draw off the solvent, allow- ing it to run through a small (5.5 cm.) filter into 200-mil Erlenmeyer. Distill off about 50 mils chloroform, using a small Bunsen flame. Extract a second and third time with the same amoimt of solvent as first used. Allow the chloroform from each extraction to run into the Erlenmeyer, then distill off all but about 10 mils. Now add 10 mils dilute sulphuric acid (1 volume concentrated acid to 5 of water) and heat on steam-bath until the chloroform has disappeared and only about 5 mils of the acid liquid remains, then treat as directed under caffein, page 837. Render the acid liquid in separator containing the codein sulphate neutral by the addition of solid sodium bicarbonate, wash out filter used in the preceding oper- ation to clarify the chloioform, once with water, allowing latter to run into the separator, then re-extract three separate times with 50 mils chloroform. Collect solvent as above directed in a second 200-mil Erlen- meyer, distilling off most of the liquid by the aid of gentle heat. Trans- fer residual chloroform to a small beaker or evaporating dish, using suf- ficient fresh chloroform for this purpose, heat gently over steam-bath to dryness, cool, and weigh as anhydrous codein. CAFFEIN, ACETANILID, QUININ SULPHATE AND MORPHIN SULPHATE IN MIXTURES. (W. O. EMERY.) 2 Preparation of Sample and Solutions. — Transfer a separatory funnel an amount (containing not less than one-fourth grain of morphin) of the powdered sample equal to, or a multiple of, a unit dose, add 20 mils of water and 10 drops of dilute sulphuric acid, then extract with three 50-mil portions of alcohol-free chloroform, wash each portion in a second separa- tory funnel with 5 mils of water and add the combined washings to the alkaloidal solution in the first separatory funnel. Filter the chloroform 1 U. S. Dept. Agri. Bu. Chem. Bull., 152, 239. 2 J. Assn. Off. Agri. Chem., Vol. 1, page 360. ALKALOIDS DERIVED FROM ISOQUINOLIN 219 extracts through a small, dry filter into a 200-mil Erlenmeyer flask and distill by gentle heat to about 10 mils. • Caffein and Acetanilid. — The caffein and acetanilid will be present in the chloroform solution, while the quinin and morphin will be found in the acid liquid. If it is desired to separate and determine the caffein and acetanilid the analyst is referred to the methods described on pages 837. Quinin Sulphate. — Add to the solution of quinin and morphin sul- phates, 4-5 mils sodium hydroxide solution (1 to 10) and extract with four 40-mil portions of chloroform, wash each portion with 5 mils of water and pass the clear solvent through a small, dry filter into a 200-mil Erlen- meyer flask. Remove the solvent by gentle distillation and titrate the residual quinin with N/50 hydrochloric acid as follows: Dissolve the amorphous alkaloid in 5 mils of neutral alcohol and titrate with N/50 hydrochloric acid to a faint red, using 2 drops of methyl red as an indicator. Heat on steam-bath until most of the alcohol has been expelled, adding, if necessary, sufficient acid to maintain the acid reac- tion. From the total number of mils of acid employed in the titration calculate the quinin sulphate. 1 mil N/50 HC1 = 8.73 mg. quinin sulphate. Morphin Sulphate. — Wash the filter, employed above, with 5 mils of water and add to the aqueous alkaline solution of the alkaloid. Now add 0.5 gram of ammonium chloride (or an amount slightly in excess of that required to free the morphin as well as convert all sodium hydroxide to sodium chloride) and, to the resulting ammoniacal solution, add 45 mils of chloroform and 5 mils of alcohol, then extract in the usual way, washing the solvent in a second separatory funnel with 5 mils of water. After clear- ing, pass the chloroform through a small, dry filter into a 200-mil Erlen- meyer flask. Repeat the extraction with three 40-mil portions of chloro- form, washing and filtering as before, finally collecting all the solvent in an Erlenmeyer flask and distilling to about 10 mils. Transfer with chloroform to a small, tared beaker, evaporate to apparent dryness, add 0.5 mil each of water and neutral alcohol, start crystallization by stirring with a glass rod and finally evaporate to dryness. Cool and allow to stand until the weight becomes constant. Check the weight of morphin, thus determined, by titration with N/50 sulphuric acid, using a drop of methyl red as an indicator. Dissolve the alkaloid in 1-2 mils of warm, neutral alcohol, then add the standard acid to a faint red. Evaporate most of the alcohol on a steam-bath, adding, if necessary, sufficient acid to maintain the acid reaction. From the volume of acid used calculate the morphin sulphate. One mil of N/50 sulphuric acid is equivalent to 7.58 mg. of morphin sulphate. 220 ALKALOIDAL DRUGS Note. — If the mixture contains acetphenetidin (phenacetin) in place of acetanilid, proceed as outlined above, except that the separation of caffein and acetphenetidin is conducted as directed on page 857. SEPARATION OF HEROIN AND MORPHIN. (J. M. DORAN) * The sample used should not contain over .2 gram of either heroin or morphin: if tablets dissolve in water slightly acidulated with hydro- chloric acid; if solid, treat with water acidified with dilute hydrochloric acid and filter; if an alcoholic solution, make slightly acid with dilute hydrochloric acid and evaporate off the alcohol before proceeding. Transfer the solution of the salts of the alkaloids to a separator, add a slight excess of ammonia, agitate with three separate additions of 25 mils each of carbon tetrachloride, passing each fraction of solvent through a 7-cm. dry filter into a tared dish. Evaporate on a steam-bath to dry- ness, heat at 100° for ten minutes, cool, and weigh as heroin. The weight may be checked by titration. Doran recommends N/25 acid and the results may be calculated to the salt by the following factors: 1 mil N/25 H2S04 = 0.01622 gram heroin hydrochloride or diacetyl morphin hydrochloride. 1 mil N/25 H2SC>4 = 0.1694 gram of the monohydrated salt, which is the commercial article, and account should be taken of this condition in reporting on sample where the question of the amount present is of moment. For the determination of the morphin remaining as a free base in the ammoniacal solution the separations recommended above may be used to advantage. SEPARATION OF CODEIN, HEROIN, AND MORPHIN. (DORAN) If these three alkaloids occur in the same formula, the codein and heroin can be removed by carbon tetrachloride and weighed. The mor- phin can be determined in the ammoniacal solution as usual. Another portion of the solution of the sample may then be treated with 10 mils of N/2 NaOH, which completely hydrolyzes the heroin to morphin with the use of heat. The codein may then be extracted from the alkaline solution by carbon tetrachloride and weighed, the alkaline liquor containing the other alkaloids is acidified, then made alkaline with ammonia and the total morphin determined. GENERAL REMARKS ON THE ESTIMATION OF OPIUM ALKALOIDS The separation of morphin from complex mixtures cannot be accom- plished with the same ease as is the case, with quinin, strychnin, cocain, 1 J. Ajner. Pharrn. Assn., 1916, 163. ALKALOIDS DERIVED FROM ISOQUINOLIN 221 and others which dissolve readily in immiscible solvents. We have observed the comparative facility with which these alkaloids can be removed from mixtures in the crude condition, and their final separation and purification brought about with certainty. From most mixtures morphin can be separated and its determination accomplished with cer- tainty, but the manipulations are not always simple. Opium and ipecac alkaloids are very often combined in medicinal products, but the complete separation of the two groups is still a matter of research. Emetin can be separated from cephaelin and of course mor- phin by shaking out with ether from a solution made alkaline with caustic alkali, but on subsequent extraction after rendering ammoniacal the cephaelin will come out with morphin. It is probable that the ipecac alkaloids will be practically all removed by making the solution alkaline with ammonia and shaking out with ether and subsequently removing the morphin with chloroform-alcohol. The mydriatic alkaloids, strychnin, aconitin, cocain, quinin, hydrastin, and sanguinarin can all be separated from morphin by shaking out with ether and chloroform from a solution made slightly alkaline with caustic alkali. When the sample consists of a pill or tablet of complex composition, the ground substance is extracted with alcohol, filtered, evaporated cau- tiously, the residue taken up with dilute acid and after adding alkali the alkaloids present are removed with ether or chloroform, and the morphin shaken out with chloroform and alcohol by either Eaton's or Buchbinder's procedure. Of- course if the product contains opium, the other alkaloids will be contaminated with the opium bases other than morphin, and if it is a question of determining the other alkaloids also the problem under these conditions will become more or less involved. Morphin pills can be dissolved in acidulated water, filtered from any insoluble material, and the morphin shaken out directly and purified. Tablets of morphin and atropin can be dissolved in acidulated water, the atropin shaken out with chloroform after rendering alkaline, and then after ammonia has been added the morphin can be removed by chloro- form and alcohol. Medicated lozenges should be dissolved in a small amount of water and the mixture, with any undissolved material, poured into an excess of alcohol about ten times the volume of the aqueous solution. After the gum has coagulated, the alcoholic solution is filtered off, the alcohol evaporated and the morphin separated from any accompanying alkaloids by the procedures mentioned above. Opium suppositories or opium ointments should be treated with petro- leum ether until the fats are all dissolved and the ether solution decanted through a filter, the residue washed with fresh petroleum ether and treated with acidulated water. The morphin can then be determined as in the 222 ALKALOIDAL DRUGS opium assay. Qulnin sulphate has been found combined with opium in some pneumonia and croup remedies of the ointment class, and the quinin can be readily determined after the oils and fats are dissolved out with petroleum ether, by treating the residue with acidulated water, adding caustic alkali and shaking out with ether. On acidulating, adding ammonia and shaking out with chloroform-alcohol the morphin can be recovered. Morphin can be determined in liquids of the chlorodyne type by evaporating a measured quantity of the sample until the solvent and volatile ingredients have been driven off, dissolving the residue in acidu- lated water, removing the coloring matter and acid constituents by shak- ing the acid solution with ether and then separating the morphin as usual. Liquid preparations in general may be assayed for morphin according to Eaton's or Buchbinder's procedures with little preliminary manipu- lation, though if other drugs are of a resinous nature the solvent holding them in solution should be expelled and the residue then taken up with acidulated water and filtered from the resin. Codein can be removed from alkaline solution without any difficulty with ether or chloroform, and it seldom occurs with other alkaloids except, of course, when it is present in opium. It is sometimes combined with antipyrin, and no satisfactory separation has been as yet evolved. Heroin can be separated from its solutions by first shaking out the cold acid solution to remove neutral substances, and then freeing the heroin with sodium bicarbonate and extracting it with ether. The pre- cautions to be observed in working with this substance have already been noted. THE IPECAC ALKALOIDS Emetin, CsoIMOCHs^ (NH)N. CephaBlin, C25H 2 7(OCH 3 )3(OH)(NH)N. Psychotrin, C 2 5H26(OCH 3 )3(OH)N 2 . The roots of several species of. Ipecac contain the three alkaloids above mentioned. Hesse x reports in addition to the above, hydroipecamin, isomeric with cephselin, and ipecamin, isomeric with psychotrin. He attributes slightly different formulas than those above which were determined by Carr and Pyman 2 and confirmed by Karrer. 3 The United States Pharmacopoeia recognizes two ipecacs, at least they are regarded by some authorities as distinct species, while in other quar- 1 Annalen, 1914, 405. 2 Chem. Soc. Trans., 1914, 105, 1591. 3 Ber., 1916, 49, 2057. ALKALOIDS DERIVED FROM ISOQUINOLIN 223 ters they are considered to be simply variations of the same species. They are designated Cephselis ipecacuanha, known commercially as Rio, Brazilian, or Para ipecac, and C. acuminata, known as Carthagena ipecac. Rio ipecac is dark brown in color and closely annulated with thick- ened incomplete rings exhibiting transverse fissures with vertical sides; the bark is thick and light brown, easily separable from the yellowish white wood. Carthagena ipecac is usually thicker than Rio and is of a grayish-brown color, with fewer annulations which are occasionally trans- versely fissured with circular scars of bark; the bark is dark brown, smooth, and horny, the wood light brown. Both varieties have dark brown stems, wrinkled longitudinally. It is generally reported that C. acuminata contains more cephaelin in proportion to the emetin than is the case in C. ipecacuanha. Indian- grown root resembles Brazilian root more closely than Carthagena. The official roots contain from 1.75 per cent to about 3 per cent of total alkaloids. There is also present a plant acid called ipecacuanhic acid, which is claimed to be a glucoside of the saponin class, and which is supposed to be the active constituent of the product known commercially as de-emeiinized ipecac. This product is really a " de-alkaloid ed " ipecac, but it often contains considerable quantities of alkaloids. Finne- more and Braithwaite x have studied a substance which they claim is identical with ipecacuanhic acid and which they call ipecacuanhin. It appears to be a glucoside containing a catechol complex and yields on hydrolysis with emulsin a sugar producing an osazone, melting 207°. It is soluble in ether, petroleum ether, and hot water, but only sparingly soluble in chloroform. When given intravenously it had no physiological action on rabbits. Various plants have been offered for sale for ipecac, some being species of Cephaelis, and others belonging to other genera. There are also a number of wild or false ipecacs, some of which have obtained more or less recognition in medicine: Undulated ipecac from Richardsonia scabia. Striated ipecac from Cephselis emetica. American ipecac, Porteranthus gillenia stipulatus. Indian Physic, P. trifoliatus; roots resemble P. gillenia but are not annulate. Goanese ipecac, Naregamia alata. East Indian Root, Cryptocorye spiralis. White ipecac, Hybanthus ipecacuanha (Violacese). White ipecac (Poaya blanca) Polygala angulata. Anchieta salutaris. Viola odorata. 1 Pharm. J., 89, 136, 176. 224 ALKALOIDAL DRUGS Triosteum perfoliatum. Heteropteris pauciflora. The roots of several of the Euphorbiacese are used as emetics. Ipecac spurge — Euphorbia ipecacuanha. Purging or Emetic root — E. corallata syn. Tythymalopsis corallata. Examination of samples of recent (1916-17) importations of ipecac has disclosed that Heteropteris pauciflora, Ipecacuanha fibrosa, and an Ionidium species have been substituted for true Cephselis. Ipecac is noted for its emetic and expectorant properties, it is used in small quantities as a tonic and often occurs in remedies recommended for dysentery, dyspepsia, and pyorrhoea. Ipecac will be found in a number of combinations used in medicine, and the mixed alkaloids, under the name of " emetin," will be encountered occasionally as the sole active com- ponent of a pill or tablet. One of the best known products containing ipecac is Dover Powder, which consists of equal parts of powdered ipecac and powdered opium with sugar of milk. This mixture is sold as a powder, alone and in pills and tablets, and mercury mass; mercury with chalk, calomel, or quinin sulphate will sometimes be found as additional ingredi- ents; combinations of ipecac and calomel; and ipecac and squill with ammonium salts are of common occurrence. Aloin, belladonna, strychnin, and ipecac is a mixture widely used, and some special laxatives include this combination with the addition of rhubarb, colocynth, and Podophyllum. Other mixtures include ipecac with strychnin, pepper, gentian, cloves, Capsicum, and sodium bicarbonate; with colocynth and mercury mass; with Conium; with morphin, potassium nitrate, and camphor; with mer- cury mass and Gelsemium; with Podophyllum and camphor; with acet- phenetidin, quinin, aconite, and opium; with phosphoius, opium, and Digitalis sometimes with the addition of quinin; with strychnin, arsenous acid, reduced iron, quinin, or cinchonidin; with bismuth subnitrate and calomel; with nickel bromide, codein, Kthium carbonate, and anise in anodynes for infants; with ammonium chloride, opium, licorice, and belladonna in cough mixtures; with opium, lead acetate, and camphor; with aconite, morphin, and tartar-emetic in fever compounds; with pepsin, Capsicum and Nux Vomica, gentian and sodium bicarbonate in anti- dyspeptic mixtures; with senega, tolu, cubeb, ammonium chloride, lic- orice, and Hyoscyamus in bronchial tablets; with Sanguinaria, morphin, atropin, aconite, tar, and tartar-emetic in cough mixtures; and with white- pine bark, wild cherry, squill, senega, Sanguinaria, opium, and potas- sium nitrate for the same purpose; with cerium oxalate for nausea. Loz- enges of ipecac, and ipecac with morphin and antimony are well known. Ipecac is combined with senega in a mixed fluid extract of the two drugs; with cimicifuga, senega, wild cherry, and licorice in a liquid com- ai ALKALOIDS DERIVED FROM ISOQUINOLIN 225 pound; and ipecac is dispensed in the form of wine and syrup both with and without opium. Syrup of morphin compound contains ipecac, senega, rhubarb, morphin, and oil of sassafras; and syrup of Irish moss (syrupus chondri compositus) contains Irish moss, ipecac, squill, senega, and opium. Emetin Emetin is an amorphous alkaloid, nearly colorless when pure, but becoming darker on exposure to light. It is strongly alkaline and com- pletely neutralizes acids. It melts about 70° C, is optically inactive. is slightly soluble in water and petroleum ether, and dissolves readily in alcohol, ether, chloroform, and benzol. It forms well-defined salts. The sulphate, acetate, and oxalate are amorphous and readily soluble in water. The hydrochloride is crystal- line and also dissolves in water. The hydrobromide and hydriodide are sparingly soluble and separate on adding a soluble bromide or iodide to a solution of emetin hydrochloride. The nitrate is also sparingly solu- ble and may be obtained as a resinous mass on adding potassium nitrate to a solution of the hydrochloride. When warmed on the water-bath with benzoic anhydride, emetin yields \benzoyl emetin, which crystallizes from absolute alcohol in white needlesTrneKmg iSS^TSG C. The cooled melt should be dissolved in ether, the derivatives shaken out with dilute sulphuric acid, the acid solution treated with ammonia and shaken with ether. On evaporation, the benzoyl-emetin will be left and can be crystallized out of absolute alcohol. Emetin hydrochloride boiled with ferric chloride, gives rubremetin hydrochloride, a scarlet substance, soluble in chloroform, melting, when air-dried, at 127-128° with decomposition, Cephaelin This alkaloid, when freshly precipitated, is colorless but soon turns yellow. It is optically inactive. It melts at various temperatures, depend- ing on the manner in which it is deposited. An alcoholic or ethereal solu- tion on evaporation leaves the base as a transparent varnish. It may be obtained crystalline from an ethereal solution in a closed vessel. It is much more soluble in petroleum ether than emetin, and differs from that alkaloid by dissolving readily in alkali hydroxides. Cephaelin on methylation with sodium methyl sulphate and sodium amyloxide yields emetin, the OH group being methylated. With methyl sulphate and sodium methoxide the imino group is methylated principally, forming N-methyl cephaelin, melting 194-195° C. 226 ALKALOIDAL DRUGS Psychotrin Psycho trin occurs in small amount in ipecac. It crystallizes in yel- low prisms, melting 138°, readily soluble in alcohol, chloroform, and alka- lies, but only sparingly soluble in ether, thus differing from emetin and cephselin. Its solution in ammonia shows a blue fluorescence. These alkaloids are always so intimately associated with each other that their analytical reactions will be discussed under one heading and not under the separate alkaloids. The mixed alkaloids give an orange or lemon-yellow color when treated with a solution of calcium hypochlorite, followed by a drop of acetic acid. They are precipitated from acid solution by the usual alkaloidal pre- cipitants and yield various colors with sulphuric acid and oxidizing agents, but none of them are especially characteristic. Sulphuric acid produces a pale yellow becoming brown on warming. Allen and Scott-Smith 1 have given details of a careful study of the color tests with special reference to the similarity of certain reactions with those given by the opium bases. The authors have established that the alkaloids give with ferric chlo- ride a blue color, later changing to green, while the opium alkaloids, pro- duce a blue-green color from the very beginning. Froehde's reagent gives with the ipecac alkaloids a purple-bluish- violet color, resembling the known reactions of the opium alkaloids but not such a pure color as afforded by morphin. Iodic acid and starch frequently, but not always, give with the ipecac alkaloids the same blue color as with the opium alkaloids. Likewise both groups of alkaloids reduce in a similar manner the mixture of ferric chlo- ride and potassium ferricyanide with the production of a blue color. The individual ipecac alkaloids exhibit different modifications and the reactions in part are not so sharp. Psychotrin appears to be the chief cause of the chief reaction with ferric chloride and iodic acid, but the possibility is not excluded that this reaction is produced by a new ipecac alkaloid, for if one treats the ipecac extract with lead acetate and decomposes the lead precipitate in the usual manner, a substance may be obtained with amyl alcohol from acid solutions, which at once reduces iodic acid, and mix- ture of ferric chloride and potassium ferricyanide. If the acid solution which has been extracted with amyl alcohol is made alkaline with sodium bicarbonate and again treated with amyl alcohol a residue is obtained which turns blue-green with ferric chloride, dirty purple red with Froehde's reagent, and blue with iron chloride and potassium ferricyanide. The ipecac alkaloids may to a certainty be distinguished from those of opium by the use of Froehde's reagent and hydrochloric acid. 1 Pharm. Post, 1903, 348. ALKALOIDS DERIVED FROM ISOQUINOLIN 227 Emetin gives with Froehde's reagent a dirty-green color which turns grass-green on the addition of hydrochloric acid. Cephselin turns purple- red upon addition of hydrochloric acid and immediately changes to Prus- sian blue. Psychotrin gives with Froehde's reagent a dull-purple color which is turned dull-green by hydrochloric acid. The ipecac alkaloids collectively (total alkaloids) turn purple-bluish to violet with Froehde's reagent and after addition of hydrochloric acid (analogous to psychotrin) give an intense blue. Opium alkaloids with Froehde's reagent give a characteristic purple color which, however, is caused to disappear by hydrochloric acid. Lowin 1 states that emetin and cephselin can be distinguished by the following tests: with Millon's reagent a 1-50 solution of emetin remains colorless in the cold, but turns yellowish on heating; a solution of cephselin turns violet in the cold and on heating becomes finally dark brown, while color changes are obtained very distinctly with a 1-1000 and are just visible with a 1-5000 solution. With mercuric acetate a 1-50 solution of emetin remains unchanged in the cold, and becomes somewhat yellowish and turbid on heating; a cephselin solution is colorless in the cold, but becomes violet and later dark grayish brown on heating, a 1-5000 solu- tion of the alkaloid giving a distinctly visible reaction. The microscopic examination of crystallized psychotrin furnishes valu- able evidence in the detection of ipecac alkaloids. A chloroformic solution of the alkaloid is shaken with a little dilute acid, and the acid solution concentrated and transferred to a watch-glass or microscopic slide fur- nished with a cell. A watch-glass or beaker is then moistened on the inside with ammonia and inverted over the acid solution. The ammoniacal vapors are absorbed by the liquid and the alkaloid is liberated, separating in characteristic crystals. Psychotrin forms very minute crystals which appear to belong to the regular system, many of them appear to be octa- hedra and are very similar to microscopic crystals of arsenous oxide, while others closely resemble granules of rice starch. In order to separate emetin and cephselin, a solution of the alkaloids in hydrochloric acid is treated with a slight excess of dilute potassium hydroxide and shaken with ether. The ether solution, after separating, is shaken with dilute alkali, and the latter, after washing with ether, is added to the original aqeous solution, which should now contain all of the cephselin, the emetin being in the ether, and may be obtained on evapo- ration. To recover the cephselin, the alkaline solution is treated with a slight excess of hydrochloric acid, then made ammoniacal and the alka- loid removed by a mixture of ether-chloroform (1-6). A conclusive identification of these alkaloids when they are present in small quantities is not very satisfactory. It can often be stated with 1 Chem. Zeit., 1903, 27, Rep. 25. 228 ALKAL01DAL DRUGS assurance that the residue under examination does not contain alkaloids giving sharply defined tests, though the reactions obtained may indicate erne tin and cephselin. Again it is not always easy to detect these bases when other alkaloids are present. If ipecac alkaloids are suspected it is a good rule to use as much of the sample as can be spared so that a suf- ficient quantity can be obtained for preparing the identification tests. The similarity between certain of the tests of these alkaloids and those of opium has already been noted, but any doubt as to the presence of the latter may be set at rest by treating a portion of the residue with form- aldehyde-sulphuric acid, which gives the characteristic purple with opium bases. The tests given by the Nux Vomica and belladonna alkaloids are not obscured by the presence of the ipecac bases. In case it becomes necessary to determine the presence of ipecac bases in a complex mixture of alkaloids, the best plan is to separate the cephselin by taking advantage of its solubility in alkali hydroxides by a procedure similar to that described above for separating emetin and cephselin. After recovering the latter and establishing its identity, the presence of ipecac in the sample may be asserted. ALKALOIDS FROM HYDRASTIS CANADENSIS, BERBERIS AQUIFOLIUM AND OTHER SPECIES OF BERBERIS, AND ALLIED ALKALOIDS Hydrastin, C2iH 2 iN0 6 . Hydrastinin, C11H13NO3. Berberin, C20H17NO4. Canadin, C20H21NO4 (Z-tetrahy droberberin) . Nandinin, C19H19NO4. Oxyacanthin, C19H21NO3 or C18H19NO3. Berbamin, C18H19NO3. Jeteorrhizin, C20H19NO5. Columbamin, C21H21NO5. Palmatin, C 2 iH 2 iN0 6 . The most important alkaloid of this group is hydrastin, which occurs in the rhizome of Hydrastis canadensis (Ranunculacese), Golden Seal, in amounts varying from .5 to 3 per cent, and is accompanied by canadin and berberin. Berberin is widely distributed, being found in Hydrastis, the roots of Berberis aquifolium (Berberidacese) or Oregon grape, B. vul- garis, common barberry, B. nervosa, B. pinnata and others, Coptis tri- folia (Ranunculacese), gold thread, C. teeta, and probably many other botanical species. Oxyacanthin accompanies berberin in the Berberis m ALKALOIDS DERIVED FROM ISOQUINOLIN 229 genus, and berbamin is found in B. vulgaris. The last three alkaloids mentioned have been isolated from the root of Jeteorrhiza Calumba, Calumba root which was formerly supposed to contain berberin, and they were probably mistaken for this alkaloid. Hydrastis, owing to its high intrinsic value, is liable to adulteration, and samples of the ground drug should always be examined very care- fully under the microscope. It will be found mixed with some of the native root drugs, serpentaria, Cypripedium, senega, Collinsonia, Jeffersonia, Trillium, etc., and according to Lloyd the whole drug has been found wholly or in part substituted by Stylophorum diphyllum. Preparations containing Hydrastis, or the alkaloids lrydrastin and ber- berin, are used for a number of different purposes. Golden Seal has tonic properties, and is claimed to increase the intestinal secretions and pro- mote the flow of bile. It is used in gastric catarrh, dyspepsia, and for troubles affecting the mucous membranes of the mouth, throat, nose, and genito-urinary organs, and the alkaloids should be sought in medicines exploited for these purposes. Berberis is used as a tonic and blood puri- fier, in syphilis, scrofulous complaints, psoriasis, etc., and Coptis trifolia has long been known as a remedy for canker and various forms of ulcer- ated and sore mouth. The latter is often administered as a masticatory, and is combined with other drugs in gargles and bitter tonics. Of the combinations met with in practice may be mentioned pills and tablets containing the extract of Hydrastis with morphin and certain astringent substances as alum, zinc sulphate, tannic acid, guaiac, boric acid, etc., sold for astringent washes and uterine antiseptics; berberin and podophillin, and extract of Berberis aquifolium and Cascara sagrada; elixirs containing Berberis with Cascara and licorice; berberin and iron pyrophosphates; Hydrastis, rhubarb, and potassium bicarbonate; tonics containing Hydrastis, senna, iron, and aromatics; utero-ovarian seda- tives and anodynes containing Hydrastis, Viburnum prunifolium, and Piscidia piscipula (Jamaica Dogwood), this same mixture being sold also in tablet form. Hydrastin is sold in the form of tablet triturates, and the hydrochlo- rate has considerable use in eye remedies. Hydrastinin hydrochlorate, prepared synthetically from hydrastin, is used in menorrhagia and for arresting postpartum hemorrhage. The term " Hydrastin " is also applied to a concentrated resinous extract obtained from the root. Calumba root is a mild, non-astringent tonic, and as it contains no tannin may be combined with iron, hence it majr be suspected in iron tonics. In tablet form it is offered combined with Nux Vomica, Cinchona, gentian, phosphorus, and chamomile. In liquid form it is used with ginger, senna, and other tonics, aromatics, and mild cathartics. 230 ALKALOIDAL DRUGS Hydrastin OCH3 I c •\ HC COCH3 ) II HC CCO V c I HC O I HC CH / O— C C NCH 3 I II I 0— C C CH 2 C C H H 2 Hydrastin, the white alkaloid of the Golden seal root, occurs in nature partly in the free state and partly combined. It crystallizes from alcohol in prisms, melting at 132° C, insoluble in petroleum ether, very slightly soluble in water, but dissolving in chloroform, benzol, ether, and alcohol, chloroform being by far the best solvent. It is a weak base, insoluble in alkalies, and may be completely removed by chloroform from solutions acidified with hydrochloric acid, resembling narcotin in this respect, to which it is closely related constitutionally. Its solutions in solvents are strongly dextrorotatory, and its acid solution is lsevorotatory. It is pre- cipitated by most of the ordinary alkaloidal precipitants, potassium bichro- mate and picric acid, but does not give precipitates with bromine water nor potassium iodide as is the case with berberin. The picrate, recrys- tallized from boiling alcohol, forms lustrous yellow needles, melting 165- 170° C. The precipitate formed with bichromate becomes bright red or pink- ish violet when touched with concentrated sulphuric acid, differing in this respect from the colors given by strychnin or gelsemin under similar conditions. Hydrastin yields protocatechuic and formic acids when fused with potassium hydroxide. On treatment with oxidizing agents opianic acid and hydrastinin are formed, according to the equation: C21H21NO6+H2O = CioHioOo+CuHisNOs Sulphuric acid when pure gives no color with hydrastin, but in the presence of potassium bichromate a brown color, changing to pinkish ALKALOIDS DERIVED FROM ISOQUINOLIN 231 violet, is produced; neither manganese dioxide nor hydrogen dioxide give any color. A solution of hydrastin in dilute sulphuric acid gives a yellow precipitate with bichromate, the precipitate when freed from liquid and touched with sulphuric acid gives a pink-violet color, soon fading. Ammonium vanadate reagent produces a pink coloration, soon chang- ing to bright red and then gradually to~ brick red, entirely different from that produced with strychnin. Froehde's reagent, freshly prepared, gives no reaction when first added, but on standing a deep-green color gradually develops. Sulphuric acid containing formaldehyde causes no color, in marked contrast to narcotin, whrch gives a purple. With nitric acid a yel- low shade is produced, but there is nothing characteristic about it. A solution of hydrastin in dilute sulphuric acid develops an intense blue fluorescence when a drop or two of N/10 permanganate is added. The fluorescent substance is not removed by ether or chloroform, differ- ing thereby from esculin. Labat 1 makes use of the formation of opianic acid for detecting hydras- tin. The alkaloid is oxidized in acid solution with permanganate and then alcohol added, the concentration being adjusted in order to obtain a 1 per cent solution of opianic acid. 2-mil portions of concentrated sul- phuric acid are treated with 0.1 mil of the alcoholic solution and then tested with certain phenols; 0.1 mil gallic acid produces a blue color, fading to brown on warming; guaiacol, red changing to blue; a-naph- thol, a gooseberiy red; /3-naphthol, a wine red; codein, violet to blue; /3-methylnaphthol, violet soon fading. The same reactions are observed with narcotin and hydrastin. Hydrastin forms condensation products with acetone and certain other ketones. The salts of hydrastin which occur on the market are the hydrochlo- ride and sulphate. The hydrochloride is readily formed when a solution of the alkaloid in absolute ether is brought in contact with In^drogen chloride gas. Both salts dissolve readily in water. The hydrobromide and hydriodide also occur, but have little or no use in medicine. The hydriodide is the least soluble of the four. Hydrastinin H / H c c=o H 2 a O— C C NHCHs I II I O— C C CH 2 c c H H 2 i Bull. Soc Chim., 1909, 5, 743. 232 ALKALOIDAL DRUGS Hydrastinin in the form of its hydrochloride has a limited use in medi- cine and is an artificial alkaloid, produced, together with opianic acid, on oxidizing hydrastin. The crystalline hydrochloride is formed by pass- ing dry hydrogen chloride through a chloroform solution of the base. Hydrastinin crystallizes in needles, melting 116-117°, slightly soluble in water and dissolving readily in the ordinary organic solvents, includ- ing petroleum ether. It is inactive. Its solution in water is alkaline and exhibits fluorescence and its alcoholic solution is fluorescent. It com- bines with hydroxylamine and forms benzoyl and acetyl derivatives. A solution of the hydrochloride when treated with a few drops of Nessler's reagent gives a precipitate which blackens instantly. Morphin, apomorphin, and picrotoxin also reduce Nessler's reagent and are, accord- ing to Jorissen, the only other principles which give a reaction similar to hydrastinin. It also reduces Tollen's reagent. The color reactions given by hydrastinin with concentrated sulphuric acid, ammonium vanadate, and Froehde's reagent are the same as those given by hydrastin. Its solution in dilute sulphuric acid, when treated with a drop or two of permanganate, shows fluorescence on dilution. Hydrastin on benzoylation with benzoic anhydride or benzoyl chloride yields a benzoylated compound melting 98-99° when crystallized from dilute alcohol. When warmed with acetic anhydride in benzole solution it yields an acetyl derivative, melting 105°. Berberin H H 2 C C /O— C C CH 2 H 2 C< | || | x O— C C NOH C C CH H || | CH C \^\ C C-OCHs I I! CH C-OCHs V c H When pure, berberin is a yellow alkaloid, the melting-point of which has not been definitely determined. It usually contains varying amounts of water which, according to some authorities, is entirely driven off at 100° C. Most of its salts are less soluble in water than the free alkaloid, ALKALOIDS DERIVED FROM ISOQUINOLIN 233 thus the hydrochloride requires 500 parts of water to keep it in solution, and is nearly insoluble in dilute hydrochloric acid. It has a bitter taste, is a weak base somewhat soluble in cold water, alcohol, and amyl alcohol, and readily soluble on warming, slightly soluble in chloroform and benzole, and insoluble in ether and petroleum ether. Chloroform and benzole will remove it from both acid and alkaline solu- tions to a limited extent, but it is best removed from solutions by a mix- ture of alcohol and choloroform. It is readily separated from oxyacan- thin and hydrastin through its insolubility in ether. Berberin forms crystalline derivatives with acetone and chloroform, from which the free base may be liberated by wanning in alcoholic solu- tion. Berberin is precipitated by nearly all of the ordinary alkaloidal pre- cipitants, Mayer's and Wagner's reagents, potassium iodide and chromate, picric acid, platinic chloride, gold chloride, bromin water, and hydro- chloric and sulphuric acids if not too dilute. Concentrated sulphuric acid dissolves berberin to an orange-yellow solution, which becomes olive green on warming, and on adding bichromate a violet shade changing to brownish green takes place. Under some conditions, depending on the purity of the residue, a black color will be observed on adding the oxidizing agent, soon changing to chocolate brown and then violet. Froehde's reagent produces a greenish brown to dark brown or violet. Nitric acid dissolves berberin to a dark reddish-brown liquid, which on dilution with water gives a yellow precipitate partially soluble in ammonia. When a solution of berberin strongly acidified with hydrochloric or sul- phuric acids is treated with a small quantity of chlorine water, cautiously added from a pipette and allowed to rest on the surface of the liquid to be tested, a zone of bright red is formed at the junction of the two liquids. A fragment of sodium nitrate stirred into a solution of berberin in con- centrated sulphuric acid gives a violet streak, Canadin, Z-tetrahydroberberin This alkaloid, in the laevo form, is present in small amount in Hydras- tis root; it melts 132.5-137° and is soluble in the ordinary organic sol- vents with the exception of petroleum ether, which dissolves it sparingly. It is insoluble in water. An alcoholic solution of iodine converts it into berberin. Tetrahydroberberin occurs in three forms, the dextro modification melting at 139-140°. The racemic form splits into its constituents by precipitating with ortho-bromcamphorsulphuric acid. Hlascwitz and Gilm obtained tetrahydroberberin, melting 167°, by reducing berberin with zinc and sulphuric acid. 234 ALKALOIDAL DRUGS Canadin liberates iodine from iodic acid and gives Prussian blue with potassium ferricyanide and ferric chloride. Its color reactions are not especially characteristic; sulphuric acid dissolves it to a yellow solution, gradually turning red, and nitric acid gives a yellow solution. Ammo- nium vanadate gives an olive-green color turning to dark black-brown. Oxyacanthin Oxyacanthin accompanies berberin in several species of Berberis and is readily separated from berberin by its solubility in ether. When thrown out of an acid solution with ammonia it is obtained in an amorphous form melting 138-150°. It may be crystallized out of alcohol or ether in the form of needles melting at about 210°. It is dextrorotatory and soluble in organic solvents, sparingly in petroleum ether, and partly removed from its acid solution by chloroform. The form in which it ordinarily occurs is known as the alpha modification, and as such, is soluble in sodium hydroxide with great difficulty; on treatment with potassium or barium hydroxide it is converted into the beta form which is readily soluble in potassium hydroxide, and cannot be removed from such a solution with ether. Ammonium chloride precipitates the beta modification from its solution in potassium hydroxide and this precipitate on drying goes over to the alpha form. Oxyacanthin liberates iodine from iodic acid, from potassium iodide in dilute sulphuric acid, and gives Prussian blue with ferric chloride and potassium ferricyanide. With Froehde's reagent it gives a violet color turning blue or green and gradually fading to yellow. Ammonium van- adate gives a dirty violet. Berbamin This alkaloid occurs with oxyacanthin and berberin in Berberis and may be separated from the former by petroleum ether in which it is insol- uble. The free base melts 197-210° according to Rudel. Its color and reducing reactions are similar to those of oxyacanthin. Nandinin Eykman reported this base as occurring in the root of Nandina domes- tica, but its properties and composition have apparently never been pub- lished. When these alkaloids of Calumba are extracted from liquid mixtures the residue is easily mistaken for berberin, the color reactions are some- what similar and the precipitates obtained and general character of the mixture suggest this alkaloid. For this reason the absence of calumba bitter, " calumbin " should be established unless one is certain that he ■■ ALKALOIDS DERIVED FROM ISOQUINOLIN 235 is dealing with a berberin-bearing drug instead of calumba. The three alkaloids from calumba all form yellow salts. Columbin This substance is a neutral princip^ and is intense^ bitter. Inves- tigation has demonstrated that it is a chemical individual, probably of lactone constitution, possessing two hydroxyl groups and melting at 182° C. Its formula is given as C28H 3 o09 : 3 It gives a diacetyl deriva- tive, melting at 218° and crystallizing iff white needles. Pure columbin is slightly soluble in cold water, alcohol, and ether, but goes into solution more readily on warming. It may be removed from an acid aqueous solution by shaking out with ether, and the residue left on evaporation purified by crystallizing the columbin out of alcohol or ether, decolor- izing if necessary by shaking witrTdry animal charcoal and filtering. Columbin gives an orange color changing to red on treatment with concentrated sulphuric acid, the solution throwing out brown flocks on dilution with water. Boiling alkalies and lime water convert columbin to columbic acid, melting 228°, slightly soluble in ether and water and readily soluble in alcohol. Columbin is not precipitated by the usual organic precipitants, and may be removed from an acid solution by ether after precipitating the alkaloids by Mayer's reagent. In this group the analyst will be concerned chiefly with the separation and identification of berberin, hydrastin, and hydrastinin ; and occasion- ally to identify columbin, and to differentiate between the columba alka- loids and those from Berberis. The other alkaloids mentioned are not used commercially. Berberin or hydrastin, when alone, are easy of identi- fication. Mixtures containing Hydrastis nearly always give indications of the presence of this drug through the fluorescence imparted to the ether shake-outs. In order to remove the alkaloids from the rest of the drug, and the other ingredients in the medicine, the sample or an evaporated residue of a liquid portion should be triturated four or five times with successive portions of 95 per cent alcohol in an evaporating dish, the united alcoholic extractions evaporated over the steam-bath, and the residue dissolved in dilute acid and subjected to the regular scheme of alkaloidal separation. Hydrastin may be completely separated from berberin by shaking out with absolute ether from a slightly alkaline solution, and berberin may be subsequently removed by alcohol-chloroform mixture. As obtained in this way, hydrastin will be contaminated with canadin, which may be separated from hydrastin by dissolving the residue in dilute acid, render- ing alkaline and shaking out with petroleum ether, in which hydrastin is almost insoluble. If the drug product under investigation contains 236 ALKALOIDAL DRUGS Berberis, the ether will remove oxyacanthin and berbamin. Berberin may also be removed from a residue of mixed alkaloids by dissolving in alcohol, diluting with water and precipitating with 10 per cent potassium iodide. It will often happen that some of the oxymethylanthroquinone drugs will be present in mixtures with Hydrastis or Berberis, and the resi- dues obtained therefrom will be contaminated with substances which will alter the color tests. These bodies may be eliminated by shaking the ethereal solutions of the alkaloids with dilute ammonia; or the alkaloids may be precipitated from an acid solution by Mayer's reagent, the pre- cipitate filtered, washed, dissolved in alcohol, and the alkaloids again liberated by alkali and removed by suitable solvents after diluting the solution with water. Quantitative Estimations. — For the estimation of hydrastin in pills or tablets containing Hydrastis extract, the sample should be ground and triturated in a mortar with 95 per cent alcohol, the alcoholic extract filtered into an evaporating dish, the procedure repeated three times, and the filter finally washed with a fresh portion of alcohol. About 10 mils of water are then added to the contents of the dish and the alcohol evapo- rated over the steam-bath. The residue is then treated with water and dilute sulphuric acid, filtered into a separator; ammonia added in slight excess and the hydrastin removed by shaking out four times with absolute ether. The ethereal extract is shaken out with dilute hydrochloric acid, the acid solution rendered alkaline with ammonia, and the hydrastin removed by shaking out four times with ether. The ether extract is then washed once with water, filtered into a tared dish, the solvent evaporated and the residue weighed as hydrastin. If the sample is a liquid it should be evaporated over the steam-bath until the alcohol and water are expelled, the residue treated with alcohol and the determination finished as above. Berberin may be determined, when it occurs in mixtures with hydras- tin, by precipitating the acid solution with potassium iodide which removes the berberin. The hydrastin may then be determined in the filtrate and the berberin converted into the acetone compound and the estimation completed according to Gordin's 1 method. The procedure is as follows: the precipitated hydriodide is washed with a 2 per cent solution of potas- sium iodide and then washed into a flask; after heating to 60-70°, acetone is added to the extent of one-third the volume of the water, and the mix- ture shaken for ten minutes; 5 mils of sodium hydroxide 10 per cent are added and the liquid shaken until the hydriodide has disappeared; the mixture is then diluted with three times its volume of water and allowed to stand overnight. The berberin-acetone is filtered off onto a Gooch crucible, dried first in a vacuum and then at 105° and weighed, 1 gram 1 Arch. Pharm., 1901, 239, 638. ■i ALKALOIDS DERIVED FROM ISOQUINOLIN 237 of the compound corresponds to 0.853 gram of berberin. To correct for the berberin-acetone compound dissolved in the mother liquor 0.0000273 gram is added per mil. In the event of the products containing berberin alone, or with oxyacan- thin and berbamin, the preliminary treatment of the sample will follow the procedure described above and the oxyacanthin and berbamin removed by shaking out with ether after rendering alkaline; the solution is then acidulated, the berberin precipitated with potassium iodide and the deter- mination completed by forming the acetone compound. Berberin may be determined titrimetrically by precipitating the hydro- chlorate with potassium-naphthalin thiosulphonate, and titrating the excess of thiosulphonate with N/100 iodine. 1 The thiosulphonate is added in excess to the solution of the alkaloid, the precipitate is filtered off, and the filtrate and washings titrated with the iodine. Each mil of the N/100 thiosulphonate solution corresponds to .003351 gram of berberin. Hydrastin is readily separated from morphin on account of its solu- bility in ether. In mixtures containing both alkaloids, after the pre- liminary treatment, a slight excess of fixed alkali is added and the hydras- tin removed by shaking out with ether; a little ammonium chloride is added and the morphin shaken out with chloroform-alcohol 2-1. ALKALOIDS OF THE CORYDALIS GROUP The Corydalis genus, Papaveraceae, embraces about 100 species, several of which have been employed in medicine. In our Materia Medica the term relates to the Turkey or Squirrel-corn, Bicuculla canadensis syn. Corydalis canadensis. The plant is small, resembling the common Dutch- man's Breeches (B. cucullaria) a closely related species, and has a yellow blossom and finely slashed leaves. It grows in moist, rich woods. The tubers, which constitute the drug, are small, roundish, with a slight peculiar smell, and a bitterish somewhat pungent and persistent taste. The drug is a tonic, diuretic, and slightly alterative, and in these par- ticulars resembles gentian, calumba, and other simple bitters. It has been employed in syphlitic, scrofulous, and cutaneous troubles, generally in the form of a liquid extract and with other drugs. It will be found in elixirs and syrups containing potassium iodide, Stillingia sylvatica, Xan- thoxylum americanum, and Iris versicolor; or with Stillingia, Iris, Chi- maphila umbellata (Pipsissewa or Prince's pine), Sambucus canadensis, Xanthoxylum berries, and coriander. The alkaloids of B. canadensis have not been carefully studied and hence we are uncertain whether or not they are the same as occur in Corydalis cava. Kraemer reports that they resemble the alkaloids of B. cucullaria, and that corydalin is one of them. 1 Arch. Pharm., 1900, 238, 6. 238 ALKALOIDAL DRUGS C. cava has been the source of practically all the material used in researches on these bases. The bulk of the work has been done by Gadamer, Ziegenbein, Dobbie and Lauder, and Makoshe and it will be given a brief summary here. Gadamer divides the alkaloids into three large groups and one of these is subdivided. I. Weak bases giving yellow berberin-like derivatives with alcoholic iodine Corydalin, C22H27NO4 m. 134-5° Cu H* ' Corybulbin. . (fad: .?}%/f/ m. 238-9° Isocorybulbin C21H25NO3 m. 179-80° II. Medium bases, not acted upon by alcoholic iodine. Corycavin, C23H23NO6 m. 216-17° Corycavamin, C21H21NO5 m. 149° III. Strong bases. 1. Bulbocapnin, Ci7Hi3N(OCH 3 )(02CH 2 )OH m. 199° Corydin, Ci 7 Hi3N(OCH 3 )3(OH) 2 m. 103-5° Corytuberin, Ci 7 Hi3N(OCH3) 3 OH m. 240° 2. Dicentrin. Glaucin. All of the above bases are removed from alkaline solution with ether except corytuberin, which is subsequently removed by chloroform. It is somewhat conflicting to place glaucin in a group of strong bases when it has been described among the Sanguinaria and Chelidonium alka- loids as a weak base, which can be removed from acid solution by chloro- form, but the author assumes no responsibility for Gadamer's grouping. Gadamer also reports protopin in the leaves of C. cava, and Heyl * reports its presence in the tubers of C. solida. Corydalin crystallizes from alcohol in prisms insoluble in alkalies, but somewhat soluble in water, and readily in organic solvents. When treated with iodine in alcoholic solution it is oxidized to dehydrocorydalin which closely resembles berberin. On reducing this substance, two isomeric inactive corydalins are formed, one melting 158-9° and the other 135°. To identify corydalin, Mulliken recommends the preparation of the nitrate, which melts with considerable ebullition from 193-200° C. The alkaloid is treated with dilute nitric acid (1-20) and well macerated. The liquid is carefully decanted, the residue dried on a porous tile, dissolved in a small quantity of boiling water, filtered hot, and the nitrate allowed to crystallize by spontaneous evaporation. 1 Apoth. Zeit., 1910, 25, 36. ALKALOIDS DERIVED FROM ISOQUINOLIN 239 Corybulbin may be separated from corydalin by dissolving the bases in hydrochloric acid, adding excess of sodium hydroxide which precipitates corydalin only, and after removing the latter, corybulbin is precipitated by carbon dioxide; or it may be separated by treating crude corydalin with hot alcohol until most of the corydalin is dissolved, and then boiling with a large quantity of alcohol, from which the corybulbin separates as a fine crystalline powder. It is nearly insoluble in water and ether, soluble with difficulty in alcohol and readily in chloroform. It can be converted into corydalin by treatment with equivalent quantities of methyl iodide and potassium hydroxide in methyl alcohol. It reacts with iodine to produce lemon yellow needles. The color reactions of some of the bases of this group are reported as follows: Reagent Corydalin Dehydro- corydalin Bulbocapnin Corycavin Corybulbin Sulphuric acid After some time red and violet Orange gradually violet-red violet. Dirty green- brown violet Nitric acid Yellow YeUow Reddish to brown Red Yellow Erdmann's reagent Yellow- green-vio- let Yellow- green- violet Blue-blu- ish violet Dirty green Yellow Froehde's reagent Yellow-pale green-blue Yellow- blue Dark blue Dark Green Red-brown green Sulpho-vanadic acid Yellow- green-blue Yellow- green-blue Bright olive-blue Dark green Brown- green The possibility of confusing an alkaloidal residue from Corydalis with one from Chelidonium must be emphasized. GELSEMIUM AND ITS ALKALOIDS Gelsemin, C20H22N2O2. Gelseminin. Semperviren. The rhizome of yellow jasmine or jessamine, Gelsemium sempervirens (Loganiacese) , official in the Pharmacopoeia, contains the first two alka- loids above mentioned, and possibly the third. In addition to the basic constituents, the drug contains about 4 per 240 ALKALOIDAL DRUGS cent of resin, emodin monomethyl ether, ipuranol, scopoletin, the mono- methyl ether of aesculetin, both free and in the form of a glucoside, and some sugar. Gelsemium is antipyretic and antizymotic and induces paralysis of sen- sibility and motility. It is used in neuralgic conditions, for ague, malaria, and sometimes for treating the morphin and liquor habits. Morphin, alcohol, and to some extent atropin are physiologically antagonistic. The drug is offered in the form of its fluid, solid and powdered extracts, as a concentration " gelsemperin "; and the alkaloid gelsemin is employed in the form of the hydrochloride. Gelsemium is combined with the Cinchona alkaloids and Capsicum in ague pills; with arsenic and ferrous sulphate and sometimes with strych- nin and Podophyllum in malaria and periodic pills; with mercury and ipecac for desentery. In tablet form it occurs combined with acetanilid, caffein, and sodium bicarbonate; with acetanilid, camphor monobromate, sodium salicylate, and Hyoscyamus for migraine. It is combined with codein, acetanilid, caffein and bromides in elixirs, and also with coca. Gelsemin hydrochloride is sometimes administered in the form of hypo- dermic tablets. Some confusion exists as to the nomenclature of the Gelsemium bases and Merck's description of gelseminin really applies to gelsemin as it is known to English writers. Gelsemin This alkaloid crystallizes in white glistening prisms, melting 178°, readily soluble in ether, chloroform, and alcohol, and sparingly soluble in water. Its solutions are dextrorotatory. Its constitution has not been determined and it is only within recent years that Moore obtained a product sufficiently pure to establish its composition as C20H22N2O2. It is a strong base and is precipitated by the usual alkaloidal reagents. Mulliken gives the composition of this alkaloid as C22H26O3N2, with a melting-point of 160° when dried in a desiccator, ancL_172° when dried at the temperature of boiling xylol or toluol. When pure it dissolves in concentrated sulphuric acid without color; and on the addition of an oxidizing agent, an intense red or purplish-red color develops, passing gradually to blue or bluish green and finally to blue or green. As gelsemin is nearly always contaminated with more or less gelseminin, the color obtained with sulphuric acid alone is reddish or brown gradually changing to pink, and on heating purple and choco- late colored tints appear. The colors obtained on adding oxidizing agents to a sulphuric acid solution of an impure gelsemin are red to purple, with purplish-red streaks following the course of the oxidizing agent, finally becoming blue-green. If cereso-ceric oxide is used, the red coloration is very intense. ALKALOIDS DERIVED FROM ISOQUINOLIN 241 A solution of gelsemin in concentrated nitric acid reddens on warming and finally becomes dark green. The pure alkaloid dissolves in nitric acid with little or no color, and on allowing the liquid to evaporate spon- taneously, a permanent bluish-green color results". Gelsemin gives characteristic crystalline precipitates with gold and platinum chlorides, and a well-defined crystalline hydrochloride which is readily soluble in water but difficultly so in alcohol. Its solubility in alcohol is made available in separating it from gelseminin, as the hydro- chloride of the latter dissolves readily in this solvent. Pure gelsemin appears to have a very slight toxic action and the effects of the commercial preparations are thought to be due to the gelseminin, which may be present in varying quantities. Gelseminin Gelseminin is the name given to an amorphous basic substance which is also obtained from gelsemium. It is apparently a mixture of two or more alkaloids. Neither gelseminin nor its salts have been crystallized. The base gives the usual precipitates with alkaloidal reagents and resembles gel- semin in its color reactions. Physiologically it is a strong poison and much more active than gelsemin. It also produces mydriasis and mix- tures of strychnin and gelseminin might on analysis be mistaken for mix- tures of strychnin and belladonna. Semperviren This alkaloid may be obtained, according to Sayre x and Stevenson, by dissolving a mixture of the crude alkaloids in chloroform and completely extracting with 1 per cent hydrochloric acid. On saturating with sodium nitrate, the nitrate of semperviren- is thrown out, and may be separated and crystallized from hot alcohol. The free base recovered from the salt crystallizes in reddish brown needles, soluble in chloroform and alcohol and almost insoluble in ether, benzol, and petroleum ether. Scopoletin, C 9 H 5 3 OCH3 Scopoletin is the principle of gelsemium which gives a blue fluores- cence with ammonia, and is a very useful substance in analytical work for establishing the presence of the drug. It is readily soluble in chloro- form from acid solutions, and on shaking the chloroform with dilute ammonia, the aqueous layer, on separation, will show a distinct blue fluorescence. 1 J. Amer. Pharm. Ass., 1915, 1458. 242 ALKALOIDAL DRUGS Scopoletin crystallizes from alcohol in long colorless needles, melting at 204° and subliming at 140-170°. It gives an acetyl derivative, melt- ing 177°. This substance has been called " gelseminic " acid and has also been mistaken for sesculin, the fluorescent substance from the horse-chestnut bark which does not sublime. Separation of the Alkaloids. — Stevenson and Sayre L in the reports of their researches on Gelsemium suggest a method for separating the alkaloids. The procedure in detail is as follows: the mixed alkaloids are dissolved in chloroform, which is shaken with several portions of 1 per cent hydrochloric acid, testing each portion with saturated sodium ni- trate, until a fraction is obtained which gives no precipitate with the reagent. The combined acid washings are treated with a sufficient quan- tity of the nitrate to remove the semperviren, and the nitrate is filtered off and washed with saturated sodium nitrate and then with a small quantity of distilled water. The filtered acid solution is preserved. The chloroform solution is then continously extracted with the 1 per cent acid until all of the alkaloids are removed, and this solution is com- bined with the filtered solution above mentioned. The acid solution is shaken with benzol and then with chloroform, several portions of each solvent being employed; after which it is rendered just neutral with sodium hydroxide, and evaporated to dryness at a low temperature. The residue is extracted with several small fractions of alcohol which dissolves the gelseminin hydrochloride and a portion of the gelsemin hydrochloride. The alcoholic solution is evaporated to a small volume and allowed to stand for some time when the major portion of the gelsemin hydrochloride will separate. After filtering the filtrate is mixed with sand, evaporated at a low temperature and extracted with acetone, which takes up the gelseminin hydrochloride. The free bases can be recovered from their salts by the usual methods of alkaloidal separation. Qualitative and Quantitative Testing. — The presence of Gelsemium as a drug either by itself or in a mixture is not difficult to establish; the scopoletin is readily detected, and following this, the identification of the bases makes the diagnosis complete. The alkaloids when alone may be identified without difficulty, the only substances for which they might be mistaken being strychnin and yohimbin, and they can be differentiated from these bases because a residue evaporated with nitric acid does not give a purple color with alcoholic potash. If, however, they occur con- jointly with the bases above mentioned their identity becomes a matter of considerable difficulty, and as has already been mentioned, a mixture of strychnin and the Gelsemium bases might be mistaken for one of strych- 1 J. Amer. Pharm. Ass., 1915, 4, 1458. Mm ALKALOIDS DERIVED FROM ISOQUINOLIN 243 nin and the belladonna alkaloids. The reason for this is due to the fact that strychnin gives a reaction similar to Vitali's test for atropin or hyos- cyamin, and the mixed Gelsemium bases produce mydriasis. To test for scopoletin and the alkaloids, the product under exami- nation, if a solid, should be extracted with alcohol, (if a liquid, the water should first be evaporated), the alcohol filtered off, evaporated, the residue taken up with dilute hydrochloric acid and filtered into a separator. The acid solution is then shaken out with chloroform, a portion of the solvent run into a test-tube and shaken with water containing a little ammonia; on separating the alkaline layer will show a bluish fluorescence if scopoletin is present. If it is desired to proceed further with the identity of scopo- letin the chloroformic solution should be washed with water, filtered, evapo- rated, and the residue crystallized out of alcohol, the product obtained subjected to sublimation at about 150° C, and the melting-point of the sublimate determined. The acid solution, after the removal of the scopoletin, is then rendered alkaline, extracted with ether, then with chloroform, and portions of the residue from each extraction tested with the several oxidizing mixtures, and the gold and platinum crystalline salts examined under the microscope to observe their characteristic forms in comparison with known specimens. In making a quantitative estimation of the amount of Gelsemium bases in a mixture, the preliminary manipulation is the same as the processes employed for identifying the alkaloids. After removing the scopoletin and other substances soluble in chloroform from an acid solution, the liquid is made alkaline and extracted with ether and chloroform, the sol- vents washed with water, run through a filter into a tared dish, evapo- rated and the residue weighed. If acetanilid and caffein have been found the acid solution must be thoroughly extracted with chloroform before rendering alkaline as these substances are both extracted from an alka- line solution. There are no satisfactoiy methods known at present for the separation of gelsemin and gelseminin from codein, strychnin, ipecac,' or cinchona alkaloids. ALKALOIDS OF THE CELANDINE AND BLOODROOT Chelidonin. Chelery thrin. Sanguinarin. a-Homochelidonin. /3-Homochelidonin. 7-Homochelidonin . Protopin. 244 ALKALOIDAL DRUGS These alkaloids occur in the two drug plants, Chelidonium majus, garden celandine or tetterwort, and Sanguinaria canadensis, bloodroot. They also occur in Stylophorum diphyllum, Bocconia frutescans, Boc- conia cordata, and Eschscholtzia Calif ornica, all of the above plants belonging to the Papaveracese. Some of them are found in Adlumia cirrhosa, Fumaria officinalis, and Glaucinum corniculatum. In addition to the above mentioned alkaloids Schlotterbeck reports the presence of other alkaloids, all of which have been summarized in the following table. It is of special interest in our work to observe that Chelidonium does not contain sanguinarin and that Sanguinaria is free from chelidonin. ALKALOIDS Drug Sanguin- arin Cheleryth- rin Protopin Chelido- nin alpha- Horn o- cheli- donin beta- Horn o- cheli- donin gamma- Homo- cheli- donin Sanguinaria Chelidonium Stylophorum Adlumia Eschscholtzia Bocconia Glaucinum ....... Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Present Drug Stylopin Diphyllin Adlumin Adlumi- din Berberin Ionidin Glaucin Sanguinaria Chelidonium Stylophorum Adlumia Present Present Present Present Present Present Eschscholtzia Bocconia Glaucinum Present Chelidonium majus is a perennial herb, 1 to 2 feet high, growing along fences, roadsides, and in waste places, and the entire plant is used as the drug. It was formerly official in the U. S. Pharmacopoeia. Chelidonium is a drastic purgative and is also somewhat diuretic, expectorant, and sudorific. It has been used for cancer and its juice is employed externally for corns and warts and to subdue traumatic inflam- mation. However, it is not a drug that is in general use and will seldom be encountered in analytical practice. Sanguinaria canadensis is a perennial herb, about 6 inches high, grow- ing in rich open woods. ALKALOIDS DERIVED FROM ISOQUINOLIN 245 Sanguinaria is used as a tonic, alterative, stimulant, emetic, and expec- torant, but is chiefly employed as a stimulant expectorant in bronchitis, croup, and asthma. The extract of the whole drug, a concentration representing the alkaloidal constituents, and alkaloidal sanguinarin in the free state and in the form of the nitrate and sulphate are all used in the compounding of galenical preparations. Extract of Sanguinaria is mixea with the extracts of Veronica virginica (leptandra), butternut, and Hyoscy- amus in liver pills; with extracts of Iris versicolor; Euonymus atropur- pureus (wahoo) and Podophyllum resin; with ammonium chloride and tartar emetic with and without opiates in croup mixtures and expecto- rants. Syrup Horehound compound usually contains the extracts of San- guinaria, Inula helenium (elecampane), Aralia racemosa (spikenard), Symphytum officinalis (comfrey), Prunus serotina (wild cherry), Mar- rubium vulgare (horehound), and Ceanothus Americanus (Jersey tea or red root). Fluid extract wild cherry compound used for making the syrup, contains Prunus serotina, Marrubium vulgare, Veratrum viride, Lactuca canadensis (wild lettuce), and Sanguinaria. Fluid extract Lobe- lia compound contains Lobelia inflata, Spathyema fetida (skunk cabbage), and Sanguinaria. White pine compound often consists of Sanguinaria and morphin acetate with Pinus strobus (white pine) bark, Prunus ser- otina, Aralia racemosa, sassafras, and balsam poplar buds. White-pine tablets may contain opium, potassium nitrate, camphor, methjd salicylate, Sanguinaria, ipecac, Polygala senega, squills, Primus serotina and Pinus strobus. Anodyne expectorants consist of about the same ingredients as white-pine syrup, and often contain chloroform in addition. San- guinaria with coltsfoot, Glycyrrhiza, and demulcents are combined in throat lozenges. The fluid extract of Sanguinaria is made with acetic acid as a men- struum, a point which should be borne in mind in case of a controversy over the presence or absence of extract of Sanguinaria in a liquid product. With the exception of Chelidonium and Sanguinaria, the other plants containing the alkaloids under consideration have seldom been used in the composition of medicines, but their possibilities are attractive and there is no reason why they should not appear in proprietary mixtures. Sanguinarin is generally regarded as the most important constituent from a medical point of view, though the percentage of chelerythrin in the drug is considerably greater. Sanguinarin, C20H15NO4 Sanguinarin crystallizes from chloroform with a melting-point of 212°. It is a white base, insoluble in alkalies, and gives intense red salts. It is probable that the molecule varies with the medium from which it crys- 246 ALKALOIDAL DRUGS tallizes and contains a portion of the solvent in its composition. It is but slightly soluble in petroleum ether, but dissolves readily in ether and chloroform. It gives precipitates with the usual alkaloidal precipitants and is indicated in the general scheme of alkaloidal analysis, when a resi- due, tested with Mayer's reagent, gives a red precipitate. It gives a red color w T ith sulphuric acid; an orange with nitric; an orange to scarlet with Erdmann's reagent; carmine to dirty brown with Froehde's; and dark green to violet brown with vanadium-sulphuric acid. The pure base dissolves in ether to a colorless solution and yields a bright- red precipitate of the hydrochloride when treated with hydrochloric acid gas. Its salts are commercial articles and are probably impure, containing a considerable proportion of the other bases. In the drug it is probable that the greater part of the alkaloid present is not in the form of a salt of the free base, but as a more stable compound whose salts are red in color and yield the base on hydrolysis. Chelerythrin, C0H17NO4 This alkaloid crystallizes from solvents with a molecule of the mother liquor from which it is freed only with difficulty. It separates from a mixture of alcohol and acetic ether in colorless crystals containing 1 mole- cule of alcohol, melting 203-204°; when crystallized from toluol it melts 257° and on drying at 100° it loses 10-11 per cent by weight giving off the odor of the solvent. It has a distinct pink tinge when viewed en masse. When dissolved in chloroform the solvent is fluorescent, but the fluorescence seems to dis- appear with increased purity. It gives bright-yellow salts with acids, and those with mineral acids are but sparingly soluble in excess of acid. It is freely soluble in chloroform but only sparingly in ether. With strong acids and Erdmann's reagent a deep-yellow color is obtained, with Froehde's reagent yellow to dirty green, and with vana- dium-sulphuric acid red to violet. A solution of chelerythrin in 95 per cent alcohol or in a mixture of alcohol and chloroform, when treated with carbon bisulphide containing iodine, gives a ruby red periodide, melting 225°. It forms a compound with gold chloride which separates from alcohol in brown needles, melting 233° with decomposition. Chelidonin, C20H19NO6 Chelidonin forms crystals containing 1 molecule of water, melting 135- 136°. The crystals when warmed or rubbed produce a cracking sound accompanied by the emission of light, visible in a darkened room. It is ALKALOIDS DERIVED FROM ISOQUINOLIN 247 dextrorotatory. Its hydrochloride is sparingly soluble and separates in crystals when hydrochloric acid is added to a solution of the sulphate. Gold chloride yields an orange-red precipitate which crystallizes violet- red from alcohol. The platinochloride is yellow, and melts 155°. The periodide is light red and black. When a solution of guaiacol in sulphuric acid is sprinkled with cheli- donin a carmine-red color is produced. Nitric acid added to a solution of the base in sulphuric acid gives a green color. Sulphuric acid alone produces a yellowish or orange color changing to violet; Erdmann's reagent gives a greenish yellow turning to violet; Froehde's reagent gives bluish green; vanadium-sulphuric acid gives green turning to blue green. It forms a benzoyl derivative which melts at 217°. Homochelidonin, C21H23NO5 /3-Homochelidonin crystallizes in clusters or rosettes of boat-shaped crystals, melting 159°. It gives a rose-pink color with sulphuric acid, intensified by vapors of nitric acid; a yellow color with nitric acid; a yellow to violet with Erdmann's reagent; Froehde's reagent produces a play of colors brown at first, then violet, blue, green and yellow; vanadium- sulphuric acid gives violet, greenish blue to brown. It is soluble in the ordinary organic solvents. When crystallized from acetic ether it melts 169° and corresponds to 7-Homochelidonin. The form seems to depend on the solvent from which it is crystallized. Both forms give a blood-red aurochloride which crystallizes from alcohol in warty crystals, melting 187°. The alpha-form of this alkaloid melts 182°. Schlotterbeck's * description of the new alkaloids of Stylophorum diphyllum and Adlumia fungosa may be summarized as follows: Stylopin, C19H19NO5, melting 202°, (o)d-315 12' in alcohol, is almost insoluble in hydrochloric acid and insoluble in dilute sulphuric acid, which serves as a means of separating it from chelidonin. It is soluble in glacial acetic acid, from which concentrated hydrochloric acid precipitates fine needles of the hydrochloride. The nitrate separates from aqueous solu- tions in clusters of needles which appear almost jelly-like en masse. Pre- cipitates are obtained with the usual alkaloidal reagents, including bro- min water, potassium iodide, picric acid, and bichromate. L~ Diphyllin, melting 216°, accompanies chelidonin and may be sepa- rated from it by fractional crystallization from ether. It gives the follow- ing color tests; nitric acid yellow, violet to carmine red, then dull green to reddish brown; Erdmann's reagent, yellowish green to bright green; Froehde's reagent, deep green, olive green to olive; Marquis' reagent, vio- let to wine red. 1 J. Amer. Chem. Soc, 1902, 1; Ibid., 1903, 596. 248 ALKALOIDAL DRUGS Adlumin, melting 188°, {ajD-r 39° 88 , gives an amorphous precipitate with gold chloride which may be crystallized out of water. It is not precipitated by platinic chloride. With sulphuric acid it gives a lemon- yellow color; with nitric acid lemon to orange; Erdmann's reagent, olive green, brown to red; Marquis' reagent, light yellow to lavender. Adlumidin, melting 234°, crystallizes in square plates usually yellow in color but white when pure. Sulphuric acid produces bright red, olive brown to pink; nitric acid orange to light yellow; Erdmann's reagent brick red, greenish to brown; Marquis' reagent, bright red. dark brown to purple. Schlotterbeck also reports an unnamed alkaloid from Adlumia, melting 176-177°, giving with sulphuric acid light yellow; Erdmann's reagent olive, brown to wine red; and no color with Marquis' reagent. GLAUCIN This alkaloid crystallizes from ether in pale yellow tablets, dextro- rotatory, melting 119-120°. It is a weak base and may be extracted from its acid solutions by chloroform. Its salts are fairly permanent and it is precipitated by the usual alkaloidal reagents. Recognition of Sanguinaria and Chelidonium. — The presence of san- guinarin may be suspected in the general scheme of alkaloidal analysis when the acid solution shows a pronounced red color. Aloes will often give a red color to a solution, but this drug has an unmistakable odor which is always prominent. If the red color disappears when the solu- tion is made alkaline and a white substance separates, insoluble in the alkaline liquid but dissolving in ether or chloroform, the worker may be reasonably sure of sanguinarin, and the evidence is further strengthened if a fluorescence is imparted to a chloroformic solution. The residue left on evaporating the solvent should be dissolved in absolute ether and treated with a stream of dry hydrochloric acid gas which will produce a precipitate of the bright red hydrochloride of sanguinarin. Chelerythrin follows sanguinarin closely in its solvent properties, and therefore a residue obtained in medicinal analysis will generally contain both alkaloids. This fact will modify the results obtained in performing color tests and unusual results must not be taken as negative indications. The color tests reported under the descriptions of the individual bases have been taken from the reports of the researches on the respective sub- stances, but they must not be considered as absolutely correct. The alkaloids of this group have not been subjected to the same degree of care- ful investigation as those of some of the other drugs and until further research has been performed much of the data must be taken with reserve. The separation of sanguinarin from chelerythrin has been effected by ■u ALKALOIDS DERIVED FROM ISOQUINOLIN 249 Kozniewski x who took advantage of tne difference in solubility of their sulphates, but such a procedure is of little use in our work owing to the limited amount of material available in any one sample. If the analyst is presented with a cough lozenge which presumably contains a large percentage of demulcent substances, and which he wishes to test for sanguinarin, the simplest procedure consists in grinding as many lozenges as can be spared and extracting them directly with ether. The ether solution will contain the bases with but little contaminating material and the pure alkaloids can then be extracted with dilute sul- phuric acid and recovered from the acid solution by adding ammonia and shaking out with ether or chloroform. The mixtures containing sanguinarin are of such a nature that the identity of the alkaloid is not difficult to determine. Kozniewski, Anz. Akad. Wiss. Krakan, 1910. Reihe, A. 235, J. Chem. Soc, Abst., 1910, 874. CHAPTER VIII ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS THE STRYCHNOS ALKALOIDS Strychnin, C21H22N2O2. */ Brucin, C23H26N2O4. Strychnicin. Tubocurarin, C19H21NO4. v^ Curin, C18H19NO3. ^ Curarin, C19H26N2O. Protocurin, C20H23NO3. Protocuridin, C19H21NO3. Protocurarin, C19H23NO2. Strychnin is found in the seed and pulp of Nux Vomica, Strychnos Nux Vomica (Loganiacese) , in the bark of the same plant " false Angostura bark," and in the seeds of Strychnos ignatia " St. Ignatius Beans." It also occurs in the root and wood of S. *columbrina L., snakewood tree; in the seeds and roots of S. tieute " deadly upas-tree," the root extract of which is employed in the preparation of a poison known as Upas Tieute or Upas Radja; and in the bark of S. malaccensis, known as Hoang-Nan. Brucin accompanies strychnin in all the above plants, but the seeds of S. rheedii contain brucin alone, and according to Bruhl S. ligustrina contains 2.26 per cent brucin, but no strychnin. Strychnicin is claimed by Boorsina to occur in the leaves of S. Nux Vomica. The other alkaloids are found in Curare, the dark resinous extract of several species of Strychnos, particularly of S. toxifera and S. castetuaca. The pulp in which the Nux Vomica seeds are imbedded contains when dry about 5 per cent of loganin, a crystalline glucoside. The extreme bitterness of the Strychnos bark, its twisted appearance, the impossibility of separating it into thin layers, and the blood-red color- ation produced on applying nitric acid to the internal coat are characters by which it is easy to distinguish it from the true Angostura bark. The Nux Vomica of commerce comes principally from India, Ceylon, Cochin-China, and Northern Australia. The Ceylon seeds contain from 250 ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 251 4.4 to 5.4 per cent of the mixed alkaloids, those from Bombay 3.2 per cent, from Cocriin-China 3 per cent, from Madras 2.75 per cent. The amount of strychnin is a little less than half. The alkaloids are com- bined with igasuric (" strychnic "j acid, which appears to be identical with chlorogenic acid. Preparations containing Nux Vomica or its alkaloids are used for general tonic purposes, and the principles often occur in remedies for neuralgia, impotence, neurasthenia, constipation, and cardiac troubles. Ignatia and Hoang-Nan containing the same constituents as Nux Vomica, are used for the same purposes though to a very hmited extent compared with Nux Vomica. Pills and tablets of Nux Vomica or of strychnin are many and varied as to their composition. The anti-constipation formulas employ aloes and strychnin, or aloin, belladonna, and strychnin, combined with one or more of the following: Cascara, ipecac, rhubarb, Podophyllum, Capsicum, Hyoscyamus, gentian, and jalap. Anti-malarial compounds contain strychnin with iron, quinin, arsenic, aloes, Hyoscyamus, Capsicum, or bismuth subnitrate. With ipecac, belladonna, colocynth, mercury, sodimn bicarbonate, often with pepsin and sometimes with iron and bismuth sub- nitrate it will be found in anti-dyspeptic mixtures. Carminatives con- tain strychnin with ipecac, gentian, and black pepper. With Cactus grandiflorus, spartein, digitalin, nitroglycerin, and strophanthin, it enters into the composition of heart tonics. Combinations of strychnin, irisin, Podophyllum, and Hyoscyamus are not uncommon. Iron, arsenic, and strychnin is a common formula, and this is often combined with quinin salts, with ipecac, aloes, gentian, cascara, creosote, and various hypophosphites, the different combinations being used as tonics. Neuralgics will contain strychnin, aconitin, quinin, and arsenic occasionally, with the addition of morphin, zinc phosphide, and Cannabis sativa. The so-called nerve tonics, aphrodisiacs, " restor- ers " and the like, contain strychnin in combination with phosphorus, cantharides, zinc salts, iron compounds, often with aloes, quinin, damiana, and gold and sodium chloride. Certain " sedatives " contain strychnin, valerianates or valerian, cocain, codein, arsenic, Cannabis sativa, and iron salts. Among the liquid products strychnin will be found in a number of combinations usually in the form of elixirs, the more important being general tonics, aphrodisiacs, heart tonics, and digestants. These will con- tain in addition to strychnin, various proportions of Cinchona alkaloids, iron salts, bismuth, and ammonium citrate, pepsin, aloin, Podophyllum, and belladonna; phosphorus and damiana; and Digitalis, Strophanthus, and nitro-glycerin. The " Hypophosphite " and " Phosphate " class of syrups nearly always contain strychnin combined with phosphates or hypo- 252 ALKALOIDAL DRUGS phosphites of potassium, sodium, magnesium, calcium, manganese, iron, quinin, and free phosphoric acid. Capsules of strychnin with cresote, codliver oil, atropin, and arsenous acid are used medicinally. Malt products often contain strychnin in combination with quinin. Preparations of ignatia are few, but it occurs in a pill and tablet formula used as an anti-neuralgic, where it is combined with opium, Hyoscyamus, belladonna, Conium, stramonium, aconite, and Cannabis sativa. It is also sold in liquid and tablet form combined with phosphorus, Cinchona, gentian, Calumba, and Nux Vomica. The curare alkaloids are used occasionally for anti-tetanics and nerve stimulants. Strychnin Strychnin occurs in the form of colorless, transparent, prismatic crys- tals or a white crystalline powder, anhydrous, odorless, permanent in the air, and having an intensely bitter taste. It is a tertiary, monacid base, extremely poisonous, and should be handled with caution. From the results of experiments conducted by Claus and Glassner x it would appear that the strychnin of commerce is not always of the same composition, in some instances corresponding to the formula C22H22N2O2 and in others to C21H22N2O2. It was apparent from this work that com- mercial strychnin probably contained homostrychnin, C22H24N2O2. The melting-point is variously given from 265° to 269°. It will dis- till without decomposition at a pressure of 5 mm. It is readily soluble in chloroform and hot alcohol and fairly soluble in benzol and amyl alcohol, much less in ether and with difficulty in water and petroleum ether. The latter solvent will, however, remove strychnin from a solution made alkaline with ammonia. Strychnin solutions are lsevogyrate and alkaline in reaction. Concentrated sulphuric acid, Erdmann's and Froehde's reagents, dis- solve strychnin without color. Its solution in nitric acid becomes yellow. It is readily soluble in dilute acids. On heating with concentrated sul- phuric acid, at 100°, a sulphonic acid of strychnin is produced which gives very insoluble precipitates with the alkali and alkaline earth metals and also with lead and copper. Solutions of strychnin are precipitated by ammonia and the alkalies, but not by sodium bicarbonate. Strychnin is not very soluble in solu- tions of the alkalies, but dissolves somewhat easily in ammonia. Strychnin forms a number of well-defined salts, some of which are readily soluble in water, while others are very insoluble. Most of the 1 Berichte, 14, 773. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 253 salts are soluble in alcohol but are insoluble in the other ordinary organic solvents. The hydrochloride, hydrobromide, nitrate, sulphate, acid sul- phate, and acetate, dissolve in water without great difficulty. The hydro- iodide is only sparingly soluble, while very insoluble and characteristic precipitates are obtained with potassium chromate, ferrocyanide and ferricyanide, mercuric chloride, sodium phospho-molybdate and phos- photungstate, potassium bismuth iodide, potassium-mercuric iodide, iodine, platinic and gold chlorides, tannic and picric acids; and the vary- ing solubilities of the isomeric salts have been of great value in the develop- ment of the chemistry of tartaric acid and other acids having stereoiso- meric modifications. It also forms a compound with sulphide of hydro- gen when treated in alcoholic solutions with this reagent or with alcoholic yellow ammonia sulphide. The precipitate obtained with potassium-bismuth iodide is one of the most insoluble combinations, closely followed by the chromate, ferrocy- anide, mercurochloride, phosphotungstate, phosphomolybdate, and mer- curoiodide. The reactions with ferrocyanide and chromate are of value in separating strychnin from brucin, and the ferrocyanide reaction has been employed quantitatively. The precipitate formed with a solution of iodine in alcohol resembles herepathite, the product of similar nature given with quinin. Strychnin is removed from an aqueous solution by animal charcoal. The color reactions of strychnin are extremely sensitive and important as a means of identifying the alkaloid. When dissolved in concentrated sulphuric acid and treated in the cold with an oxidizing agent a purple color develops, more or less fleeting, depending on the quantity of the alka- loid and the particular agent employed, and which finally becomes pale cherry-red. Potassium bichromate probably has been employed as an oxidizing agent to a greater extent than any other. Allen prefers man- ganese dioxide, and other substances, ammonium vanadate, cerosoceric oxide, potassium ferricyanide have been highly recommended. The play of colors depends on the quantity of material present. With sufficient of the alkaloid, the full change from blue to purple, purplish-red, cherry red, and finally yellow, will be noted, but when the amount is small a purple changing rapidly to yellow will be the only marked characteristic. When the quantity is very small it is advisable to dissolve the oxidizing agent in the acid before adding the latter to the residue under examination. This reaction, while very characteristic of strychnin, is unfortunately given in similar manner by other drug products which are extracted from alkaline solutions under the same conditions that strychnin would be with- drawn, and while in large amount there might be differences in the reac- tion sufficient to show wherein the product was not strychnin, there would always be a doubt, especially in forensic work, unless fully substantiated 254 ALKALOIDAL DRUGS by other tests, and when the quantity was small the difficulty of differ- entiating would be well nigh impossible. Some substances give colors with sulphuric acid alone, codliver oil being one which, when pure, produces a beautiful display of shades, from purple through crimson, to brown. Certain glucosides and other prin- ciples produce colors, but most of them are removed from acid solution by immiscible solvents. Anilin is stated to give with sulphuric acid and oxidizing agents a green color, changing to blue and eventually becoming black. Allen states that colocynth resin gives a very similar reaction to strychnin, but is removed by agitating the acidulated solution with benzol or ether. The writer found, however, that when working with an extract of colocynth, sufficient material remained in solution after previously shaking out the acid liquid with immiscible solvents, to appear later in the residues obtained by shaking out the alkaline solution and give a pur- ple tint with sulphuric acid and oxidizing agents. The reaction in this case, however, in no way resembled that obtained with strychnin, for a dirty color first appeared and after several minutes a purple shade was apparent in thin layers. It has been shown that residues obtained by shaking out alkaline solutions of the following drugs with immiscible solvents give a purple reaction with sulphuric acid and bichromate, namely, Gelsemium, Hy- drastis, opium, Sanguinaria, and yohimbe. The similarity in the reactions of strychnin and yohimbin is of interest, as the drug containing the latter alkaloid has of late been exploited as a remedial agent for the same pur- poses that strychnin has been used. It has been claimed to possess aphro- disiac properties and might be suspected in mixtures advertised for tonics and the like. When working with small quantities the reactions are so much alike that one could form no conclusion as to which alkaloid was present. In larger amount the yohimbin gives a purple, changing to reddish and then to olive green and in still larger amount the color is first an indigo blue. The reaction with ammonium vanadate, however, is so nearly identical with that given by strychnin that no distinction can be drawn with any safety. However, yohimbin forms very few salts which have any characteristic form under the microscope, while those given by strychnin are well defined and can be distinguished readily, and furthermore its physiological action is different. There is little danger of confusing strychnin with the principle of colocynth, which gives the purple color with sulphuric acid and bichromate, and as regards the alka- loids of Hydrastis, Gelsemium, and Sanguinaria, which act similarly, none gives the purple color with nitric acid and alcoholic potash subsequently described, and there are a number of distinctive characteristic reactions for these substances which are fully described under their respective headings. With ammonium vanadate, berberin gives a red, soon chang- ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 255 ing to plum-color, and gelseminin a magenta, changing to blue green. The purple color given by the opium alkaloids would hardly be mistaken for that given by strychnin, as it is very lasting. It was found on inves- tigation that narcein and papaverin were the two alkaloids giving the purple tint, no similar reaction being obtained with thebain, narcotin, codein, or morphin. Curarin gives virtually the same color reaction as strychnin, and a ptomain has been described giving a similar oxidation test. In small proportions brucin exercises no injurious influence on the oxidation test for strychnin, but when much is present it interferes in a marked manner. Hence it is safest to separate the strychnin first as chromate or ferrocyanide by precipitation and after filtering to examine the solution for brucin. Another method directs the solution of the substance in concentrated sulphuric acid, adding a trace of nitric acid or potassium nitrate and waiting until the red color changes to yellow, when a crystal of potassium bichromate will give the characteristic strychnin reaction. The writer has obtained good results by shaking out the alkaline solu- tion two or three times with petroleum ether and testing the residue left on evaporation of the solvent, for strychnin. Then on shaking out with chloroform the brucin will be removed and may be identified by testing the residue on evaporation. Strychnin when evaporated with concentrated nitric acid leaves a yellowish residue which becomes a beautiful purple on treatment with a few drops of alcoholic potash, the reaction being very similar to that given by atropin. In connection with this test, it is of interest to note that yohimbin gives the same reaction. When working with extract of Nux Vomica it was found that only the alkaloidal portion removed by petroleum ether would give the purple color on adding the alcoholic pot- ash, for the red color produced by the nitric acid on the brucin masked the purple tint given by the strychnin. Extracts from coca leaf and Colchicum have been found to give purple colorations when this test was applied. Buchbinder has developed a color reaction which is very character- istic and little affected by impurities. The reaction is based on a test first published by Malaquin and then studied. by Deniges. Zinc amalgam is prepared by treating granular zinc with a little concentrated hydro- chloric acid to clear the surface. The acid is poured off and the metal covered with 1 per cent solution of tartar emetic, shaking occasionally during one hour, 1 mil of saturated solution of mercuric chloride is added for every gram of zinc, followed by a few drops of concentrated hydro- chloric acid, and after one-half hour the solution is poured off, the zinc washed and dried. To the dry alkaloid or to 0.5 mil of an aqueous solu- tion, 0.5-1 gram of the zinc amalgam is added followed by 0.5 mil con- 256 ALKALOIDAL DRUGS centrated hydrochloric acid. After ten to twenty minutes the solution is poured from the zinc, a few drops of 0.02 per cent potassium ferrocy- anide solution added, when a color varying from pink to rose red is pro- duced. There are a number of other color reactions reported for strychnin, and their use subsequent to the others above mentioned are of value in differentiating stiychnin from those substances which give the oxidation tests. When treated with nitric acid and potassium chlorate after warming, an intense scarlet coloration is produced. This is changed to brown on adding ammonia, and on evaporation to diyness a dark green residue is left, soluble in water with a green color, changed to orange-brown by caustic potash and becoming green again on adding nitric acid. Zinc chloride gives a scarlet reaction with strychnin. A dry residue is moistened with a solution of 1 gram of melted zinc chloride in 30 mils of water and dried again. Brucin prevents the formation of the scarlet color, a dirty-yellow color developing. Veratrin will also give a red color and delphinin a red-brown. The appearance of the salts of strychnin under the microscope fur- nishes one of the most conclusive means for identifying this alkaloid. Gelseminin, which also gives an oxidation reaction similar to strychnin, has the same physiological action on the frog. Brucin Brucin is very similar to strychnin, and like the latter is a monacid, tertiary base. It contains two methoxyl groups, while strychnin con- tains none, the difference in the molecular weight of the two bodies cor- responding to the difference in their two methoxyl groups. On this account and from other data deduced from a study of the oxidation products, it appears that brucin is the dimethoxy-derivative of strychnin. Commercially it may be prepared by taking advantage of the insolu- bility of its oxalate in absolute alcohol, the oxalate of strychnin being dissolved; or the mixed alkaloids may be treated with cold absolute alco- hol or acetone which dissolves the brucin readily, leaving most of the strychnin behind. The commercial product has been claimed to consist of two homologous alkaloids. Brucin crystallizes from water with two or four molecules of water, ordinarily four, forming monoclinic prisms or shining leaflets, white, odor- less, and very bitter. From alcohol it is stated to crystallize with two molecules of water. The crystals melt in their water of crystallization when heated a little over 100° C. and the anhydrous base dried at 150° melts at 178° C. It is lsevorotatory. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 257 It is much more soluble in water and alcohol than strychnin, dissolves readily in chloroform and benzol, somewhat soluble in ether. Allen claims that it will dissolve in 120 parts of petroleum ether, while the writer has found that in shaking out an alkaline solution of the mixed bases some of the strychnin will be removed by the petroleum ether, leaving the brucin behind. This, however, may be due to the greater solubility of the brucin in water. It is much less poisonous than strychnin, the physiological activity of the latter having been variously estimated as being 10 to 38 greater than that of brucin. It is a weaker base than strychnin, but forms a number of well-defined salts. The hydrochloride, hydroiodide, nitrate, and sulphate are all soluble in water. The chromate and ferrocyanide are much more soluble than the corresponding strychnin compounds and are of value in effecting a separation of the two alkaloids. The ferricy- anide and hydrochloroplatinate are characteristic compounds showing well-developed forms under the microscope, and heavy precipitates are obtained with iodine-potassium iodide, potassium mercuric iodide, potas- sium bismuthous iodide, tannic and phosphomolybdic acids. When a solution of brucin in absolute alcohol is treated with alcoholic ammonium sulphide containing dissolved sulphur a product is formed having the composition (C22H2gN204)2H2Ss2H20, which may be obtained as orange- red crystals. Brucin is of value in separating racemic acids as it forms salts having different solubilities. Brucin does not resemble strychnin in its action with sulphuric acid and oxidizing agents. Pure sulphuric acid dissolves it without color, while the presence of a trace of nitric acid produces a reddish tint. On adding concentrated nitric acid in the cold to a brucin residue a scarlet or blood-red coloration is produced which on heating changes to yellowish red and finally to yellow. On adding a few drops of freshly pre- pared dilute stannous chloride solution, an intense violet color will appear, which changes again to yellow or red on heating, and again reappears on the addition of more stannous chloride. To perform this test success- fully the amount of nitric acid used should be small. Mauch claims to obtain excellent results by a modification of this test in which the brucin is dissolved in a 60 per cent aqueous solution of chloral hydrate. A small quantity of the mixture, about 0.5 mil, is placed in a test-tube and a few drops of nitric acid added and the whole shaken and poured carefully onto the surface of about 2 mils of concentrated sulphuric acid, when a yellowish-red or deep red zone, depending on the quantity of brucin present, will develop. As soon as the upper layer becomes yellow, stan- nous chloride is cautiously added by means of a pipette in order to form a top layer and on the dividing line an intense violet zone will form. The stannous chloride solution recommended consists of 1 part 258 ALKALOIDAL DRUGS stannous chloride in 9 parts hydrochloric acid having a specific gravity of 1.12. The orange color produced by adding nitric acid to morphin remains unchanged on the addition of stannous chloride. If the cold nitric acid be added to solid bmcin so as to develop the color, and the mixture then largely diluted with water, a body called kakotelin separates in yellow flocks. The filtered liquid, after neutral- ization by ammonia, gives a precipitate of calcium oxalate on treatment with calcium chloride. The precipitated kakotelin may be dissolved in dilute hydrochloric acid and crystallized therefrom in orange-red or yellow scales. Its composition is C2oH22(N02)2N205. Potassium bichromate throws down from solutions of brucin salts a yellow precipitate of brucin chromate which is insoluble in acetic acid, but soluble in nitric acid with a red color. Mercurous nitrate added to an aqueous solution of a brucin salt pro- duces no change, but on warming a carmine color appears. A residue obtained on evaporating a solution of brucin in concentrated nitric acid will change to grass green on the application of fumes of ammonia gas, and the green product dissolves in hydrogen peroxide with formation of a violet color. This test, however, is not delicate in the presence of strychnin. The red coloration produced by brucin in the presence of nitric acid is of value for the detection of nitric acid or nitrates in water. A drop of the water in question is treated with several drops of brucin solution in water (1-2000), several drops of hydrochloric acid then added and shaken after the addition of a few mils of sulphuric acid. In the presence of a nitrate a rose to a red color develops, quickly changing to yellow. Brucin forms a number of well-defined derivatives. On passing nitrogen trioxide into an alcoholic solution of the alkaloid, brucin nitrate at first separates, but again dissolves, forming a red solu- tion, from which dinitrobrucin, C23H24(NC>2)2N204, separates as a heavy, granular, blood-red precipitate. By washing with alcohol and ether, it is obtained as an amorphous, velvety vermilion-colored powder, easily soluble in water, sparingly soluble in alcohol, and insoluble in ether. Separation of Strychnin for Purposes of Identification. — If the sub- stance is a solid, extract with 95 per cent alcohol; if a liquid, first evapo- rate the water, and then extract with the alcohol. Evaporate the solu- tion until the alcohol has been driven off. Digest the residue with normal sulphuric acid and filter into a separator; add ammonia in excess and shake out three times with Prolius mixture. Filter the combined por- tions of the solvent and evaporate over the steam-bath. Dissolve the residue in normal sulphuric acid, pour the solution into a separator and shake out first with chloroform and then with low-boiling 40-50° petro- M ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 259 leum ether, discarding the solvents. Add excess of ammonia to the aque- ous solution and shake out three times with petroleum ether. Collect the solvent in another separator, wash with water, filter, and evaporate over the steam-bath. The petroleum-ether residue yields a strychnin of great purity, practically free from brucin. Quantitative Determination of Strychnin and Brucin. — If a medicinal agent contains no other alkaloid-bearing drug than Nux Vomica, nor any alkaloid except strychnin the determination of the amount present is attended with little trouble other than attention to details in the manipu- lation and possibly special treatments depending on the other ingredients. If the product contains but a small amount of solid material and no gum or emulsifying substances, the alkaloids may be removed by shaking out the ammoniacal solution with chloroform at least three times after first driving off any alcohol. If both strychnin and brucin are present the two may be separated and determined by the nitric acid process as described in the assay of Nux Vomica. This method is simpler and prob- ably more accurate than the ferrocyanide process recommended by earlier workers. If the residue left on evaporating the chloroform contains no brucin it should be dissolved again in dilute sulphuric acid, the solution shaken out with ether and chloroform, then rendered ammoniacal and the strych- nin removed by chloroform. The principal alkaloidal drugs which are used in combination with Nux Vomica include belladonna, coca, ipecac, Conium, and Stramonium, the two latter but seldom. The same drugs will be found in products containing strychnin alkaloid and in addition strychnin may be combined with quinin, morphin, aconitin, hyoscyamin, and spartein. The Nux Vomica alkaloids may be separated from the coca bases by dissolving the weighed residue of both in dilute hydrochloric acid and subjecting the mixture to the heat of the steam-bath for four hours in a digestion flask. The solution should then be shaken out with ether and chloroform, ammonia added in excess and the strychnin and brucin removed by chloroform. Strychnin and brucin may be separated from atropin by precipitating the former with platinic chloride. The precipitate should be washed with platinic chloride, and the strychnin and brucin subsequently recovered from the same. The atropin may be separated from the filtrate by adding ammonia, filtering, and shaking out with chloroform. The same prin- ciples may be employed in separating a mixture of the alkaloids of Nux Vomica, coca, and belladonna. Determination of Strychnin in Tablet Triturates. — Transfer a care- fully weighed amount, .3000 gram, of the powder to a 200-mil Squibb separator and moisten with 5 mils water. Add 1 mil stronger ammonia 260 ALKALOIDAL DRUGS water. Agitate with 25 mils chloroform and allow to stand until separa- tion is complete. Draw off the chloroform into a second separator and repeat the agitation twice more with 25-mil portions of the solvent. After combining all of the fractions, wash the combined chloroformic solutions by agitation with 10 mils of distilled water and allow to stand fifteen minutes. Introduce a pledget of absorbent cotton into the stem of the separator and run off the chloroform into a tared dish, but do not allow the wash water to enter the orifice of the stop-cock. Add 10 mils chloro- form and when the water has entirely risen to the surface, run off the chloroform into the tared beaker. Wash off the outer surface of the stem of the separator with a little chloroform and then evaporate over a steam water-bath, using a fan or blower and removing from the bath as the last portions evaporate to avoid decrepitation. Dry at 100° to a constant weight and weigh as strychnin. The weight of strychnin may be checked by dissolving the residue in neutral alcohol, adding an excess of N/10 sulphuric acid and titrating back with N/50 potassium hydroxide. Strychnin to Strychnin Sulphate 1.2815 according to U. S. P. One mil N/10 sulphuric acid is equivalent to 0.03342 gram of strych- nin and 0.04282 gram strychnin sulphate, crystalline (5H2O). In some cases, especially where the solvent dissolves substances from the tablet other than strychnin, it will be necessary to adopt the follow- ing modification of the above: The procedure is followed down to but not including the washing of the combined chloroform extract with water. Discard the alkaline solu- tion remaining in the first separator. Treat the combined chloroform extracts with 10 mils N/1 sulphuric acid and agitate. Allow to stand until separation is complete and collect the chloroform in a second sepa- rator. Repeat the extraction with N/1 sulphuric acid twice more, dis- card the chloroform and combine the acid fractions. Add stronger ammonia in excess, cool, and shake out with three successive portions of 25 mils each of chloroform, finally combining all fractions. Wash the combined chloroform solutions by agitation with 10 mils of distilled water and allow to stand fifteen minutes. Draw off the solvent through a pled- get of absorbent cotton into a tared dish and finish the determination precisely as described. It has been the experience of the author that, in conducting assays of strychnin, reliance should be placed on a gravimetric estimation, and not on one obtained volumetrically. Determination of Strychnin in Liquid Products. — The method herein described is applicable to elixirs of iron and strychnin, quinin and other alkaloids being absent. Take a 50-mil volumetric flask, fill to mark with sample and weigh. Pour into an evaporating dish, washing out the flask with water and evap- ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 261 orate off alcohol. Transfer to an 8-ounce Squibb separator. Add excess of ammonia. Agitate with 25 mils chloroform and allow to stand until sepa- ration is complete. Draw off the chloroform into a second separator and repeat the agitation twice more with 25-mil portions of the solvent. After combining all of the fractions, wash the combined chloroformic solutions by agitation with 10 mils of distilled water and allow to stand fifteen minutes. Introduce a pledget of absorbent cotton into the stem of the separator and run off the chloroform into a tared dish, but do not allow the wash water to enter the orifice of the stop-cock. Add 10 mils chloroform and when the water has entirely risen to the surface, run off the chloroform into the tared beaker. Wash off the outer surface of the stem of j the separator with a little chloroform and then evaporate over a steam water-bath, using a fan or blower and removing from the bath as the last portions evaporate to avoid decrepitation. Diy at 100° to a constant weight and weigh as strychnin. Calculations as above. Quantitative Estimation of Strychnin in Presence of Quinin (G. N. Watson 1 ). — Dissolve .05 to .1 gram of the mixed alkaloids (depend- ing on the amount of strychnin present) in 5 mils alcohol-hydrochloric acid mixture (9 parts alcohol 95 per cent and 1 part dilute hydrochloric acid), add 20 per cent solution of platinic chloride, drop by drop, while slightly agitating the mixture until the precipitation is complete. Add 5 mils more of the solvent, cover with a watch-glass, set aside for one hour filter onto a Gooch, wash with alcohol, dry at 100° C. for fifteen minutes, cool and weigh. If the proportion of quinin is large, it will be necessary to add from 5 to 15 mils more of the solvent before filtering. It will also be necessary to decompose the precipitate with sodium hydroxide, dis- solve out the strychnin with chloroform, evaporate, dissolve the residue in the alcohol-hydrochloric acid mixture, and repeat the precipitation with platinic chloride. The chlorplatinate of strychnin contains 62 per cent of alkaloid. The quinin can be determined in the filtrate and washings by adding alkali, agitating with ether, separating, evaporating the ether, and weigh- ing the residue. To make this separation applicable to elixirs containing strychnin and quinin, a measured quantity of the sample should be made alkaline with ammonia and the alkaloids removed by means of Prolius mixture. After separating and evaporating the solvent the residue is subjected to the above procedure. Separation and Determination of Strychnin and Quinin (H. E. Buchbinder). — This procedure is applicable for determining small quanti- ties of strychnin in the presence of comparatively large quantities of quinin 1 Journ. Amer. Pharm. Ass., 1915, 935. 262 ALKALOIDAL DRUGS and can be used for assaying the elixirs of iron, quinin, and strychnin of the National Formulary. Take 50 mils of the sample, carefully measured and weighed. Transfer to a separator, dilute with water, and render ammoniacal. Shake out six times with ether-chloroform mixture (3-1). The extracts are com- bined, and the bulk of the solvent dispelled, the remainder being collected in a tared beaker and the container used for evaporation, carefully washed free from all alkaloid with the ether-chloroform mixture. Expel the sol- vent and dry at 100-105°. Cool and weigh as combined alkaloids. Dissolve the residue in 10 mils of alcohol, add 4 mils N/2 hydrochloric acid or sufficient to render the solution red to methyl red, with 1 mil N acid in excess for every 20 mils of the aqueous solution as finally made up (see below). (The volume of the solution is to be regulated by the amount of quinin present.) Add 36 mils water. (If there is more than six grams of total alkaloid add about seven mils of water for every addi- tional gram of quinin.) Add 3 mils saturated solution potassium oxalate. (Use 1 mil for every gram or less of quinin and 1 mil for every 20 mils of aqueous solution.) Stir and when precipitate has settled, place on steam- bath and heat to boiling temperature. Add a little alcohol to take up the undissolved precipitate at the boiling-point. Remove from bath, allow to cool spontaneously, breaking up surface film from time to time. Allow to stand at least five hours. Filter with vacuum, preserving fil- trate, and collect crystals on a plug of cotton inserted in the stem of an ordinary funnel. Wash six or seven times with cold water. Concen- trate filtrate and washings until all of the alcohol has been removed. Cool. Should there be a second crop of crystals, heat to redissolve, add J to 1 mil N/1 hydrochloric acid and repeat above procedure. Adjust in a flask to a 5-7 per cent sulphuric acid solution at 50 mils, using water and dilute sulphuric acid. Add 4 mils potassium ferrocyan- ide solution 10 per cent, drop by drop, stirring constantly. Allow mix- ture to stand overnight. Filter and wash twice with 5-mil portions of 5 per cent sulphuric acid containing a few drops of potassium ferrocyanide. (Do not attempt to remove all of the precipitate from the flask.) Trans- fer precipitate on filter to 1 a small separator using a fine jet of water. To the flask add 5 mils strong ammonia and 15 mils chloroform. Agitate and pour into separator. Rinse and agitate flask twice more with 10- mil portions of chloroform, pouring each into separator. Agitate the sepa- rator, collect chloroform in another separator and repeat the extraction twice more. Combine all of the chloroform extracts, wash with water, filter into a tared beaker through a plug of absorbent cotton in the stem of the separator, wash out separator and cotton with a portion of chloro- form, evaporate solvent, dry at 100-105° and weigh. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 263 ALKALOIDS OF PEGANUM HARMALA Harmin, C13H12N2O. Harmalin, C13H14N2O. Harmalol, Ci 2 Hi 2 N 2 0. These alkaloids occur in the seeds of Peganum harmala (Zygophyl- lacese), an herbaceous plant growing in Southern Europe and parts of Asia. The seeds are called Harmal or Ispanol and in India are used as a genito-urinary stimulant, anthelmintic, and emmenagogue. They are also narcotic and are used for the same purposes as Cannabis sativa. These alkaloids or preparations containing the drug are not used to any great extent. Extract of P. harmala is used as a red dye. Harmin Harmin crystallizes from alcohol in needles, melting 256-257°, inactive, subliming unchanged and sparingly soluble in water, alcohol, and ether. Its salts are colorless and show an indigo-blue fluorescence in aqueous solution. It dissolves in concentrated sulphuric acid to a greenish fluores- cent solution. Harmin contains an OCH3 group which may be eliminated by HC1 or HI, yielding harmol, a phenol. The latter crystallizes in needles melt- ing 321°, Harmalin This alkaloid crystallizes from methyl alcohol in plates or needles, melting with decomposition 238°. It is optically inactive, almost insolu- ble in water, sparingly soluble in alcohol and ether, and may be precipi- tated from an alcoholic solution by ether. Its salts are yellow and in aqueous solution,. show a blue fluorescence, but the solution in concen- trated sulphuric acid does not fluoresce. When dissolved in cold pyridin and treated with acetyl chloride, har- malin forms an acetyl derivative which crystallizes from alcohol in needles melting 204-205° C. Harmalin contains an OCH3 group which is eliminated by HC1, yield- ing harmalol, a phenolic alkaloid, which crystallizes in red needles, melt- ing 212°. It is probable that the latter substance exists to a certain extent in the plant. Harmalol dissolves in water with considerable difficulty, yielding a yellowish solution with fluorescence. Acids or alkalies destroy the fluorescence, 264 ALKALOIDAL DRUGS, ALKALOIDS OF THE ACONITE GROUP Aconitin, C34H47NO11. f Japaconitin, C34H49NO11. Indaconitin, C34H47NO10. Pseudaconitin, C36H51NO12. Bikhaconitin, C36H51NO11. Jesaconitin, C40H51NO12. Lycaconitin, C27H34N2O6 • 2H2O. Myoctonin. ^-~ Lapaconitin, C34H48N2O8. Septentrionalin, C31H48N2O9. : Cynoctonin, C36H54N2O13. ^Atisin, C22H31NO2. Palmatisin. Most of the different species of Aconitum (family Ranunculacese) con- tain one or more characteristic alkaloids, some extremely poisonous, and others with feeble toxic properties, and from a close study of some of the more commonly known of these plants, it appears that each is characterized by a distinct alkaloid. The alkaloids occur in all parts of the plants and in some pharmacopoeias both the leaves and the root are official, though in ours, only the root is recognized. The plant designated in the U. S. Pharmacopoeia is A. napellus. The root is about 2-4 inches long and f to 1 inch in diameter at the widest portion, being tuberous and of irregu- lar conical form, brownish externally, white or light brown and starchy within. It is biennial and normally paired, one tuber of each pair when mature bearing a flowering stem, the other having a bud. The parent tubers may be distinguished by the scar of the stem, and the spongy or hollow condition of the root. The fresh leaves have a faint narcotic odor, and a bitterish herbaceous taste, afterwards acrid with a feeling of numb- ness and tingling on the inside of the lips, tongue, and* fauces which may last an hour or more. The dried leaves produce the same sensation. The root has a sweetish taste at first, but afterwards the same effect as the leaves. Of late years much "Japanese Aconite " has been coming into the markets of the United States. The species yielding this drug is A. fisheri. The drug usually consists of mother (with stem bases) and daughter tubers (with buds), which may be distinguished from those of the official aconite by their much smaller size and weight, less wrinkled, and not twisted appearance, more or less short conical shape, generally more mealy con- dition due to starch, and microscopically by the different arrangement of the fibro-vascular bundles, which is usually not so markedly star shaped. ALKALOIDS WHICH PROBABLY CONTAIN A PRYIDIN NUCLEUS 265 Adulteration of aconite with Imperatoria ostruthium, masterwort, is reported. Commercial aconitin may consist of a mixture of one or more alkaloids, depending on the drug from which the extraction was made. The whole question of aconite analysis has been the subject of considerable contro- versy, but Dunston and his collaborators have done a great service in sifting out the data and showing the source of the various aconitins. A. napellus contains aconitin. A. fischeri contains japaconitin. A. chasmanthum contains indaconitin. A. dinorrhizum contains pseudaconiton. A. spicatum contains bikhaconitin. A. japonic um contains jesaconitin. A. vulparia or A. lycoctonum contains lycaconitin and myoctonin. A. lycoconum or A. septentrionale contains lapaconitin and sep- tentrionalin. A. hetrophyllum contains atisin. A. palmatum contains palmatisin. In addition to these there are a number of aconites which contain bases as yet little studied. Aconitic acid is apparently a constant constituent of aconite and it is probable that the alkaloids are in part combined in the plant. The interest of the drug analyst will be chiefly confined to the chem- istry of A. napellus, though, as indicated above, the commercial alkaloids may consist of one or many individuals of the aconite group. These alkaloids are extremely poisonous, their employment as remedial agents is limited, and they will be encountered only rarely in the general run of drug work. Aconite is a cardiac and nervous sedative, and is used in fevers as a diaphoretic, in cardiac hypertrophy, colds, neuralgia, rheumatism, and gout. Its antidote is Digitalis. The alkaloid aconitin is dispensed in the form of pills and tablets, usually of small grainage, t^q down to 10 \ or less, and it is also used in ointments. Extracts of both root and leaves occur as such, and in pills alone. Neuralgic pills contain aconite combined with other strong drugs, including morphin, strychnin, arsenous acid, and quinin; one of the old-fashioned so-called " shot-gun " prescriptions contains aconite with Hyoscyamus, ignatia, opium, belladonna, Conium, stramonium, and Cannabis; fever mixtures contain aconite with morphin, tartar emetic, and ipecac; also with Bryonia and belladonna; cold mixtures consist of aconite, quinin, Capsicum, ipecac, and opium; aconite, quinin, ammonium chloride, camphor, opium, and belladonna; aconite, sanguinarin, mor- 266 ALKALOIDAL DRUGS phin, atropin, ipecac, tar, and tartar emetic for coughs; aconite, bella- donna, aloin, calomel, and quinin; aconite, camphor, opium, and potas- sium nitrate; aconite, morphin, atropin, and calomel; aconite, Bryonia, belladonna, and mercuric iodide for tonsillitis; aconite, Cimicifuga, bella- donna, and Colchicum for sciatica; aconite, quinin, opium, ipecac, and acetphenidin. Aconite is seldom dispensed in liquid preparations owing to the ease with which its active constituent is decomposed. In fact, when the drug is dispensed in pills and tablets it is never safe to depend on its potency unless chemically or physiologically tested, because the manipulation of pill-making is often rigorous enough to break down the highly sensitive aconitin. The chemical structure of the aconitins is still a subject of research, but it is known that they are all derivatives of bases, probably closely related, known as " aconins." Dr. Carr * in the new edition of Allen has summarized the situation as follows: Name Composition Formula OAc Aconitin Acetylbenzoylaconin C2iH 27 3 N— (OMe) 4 OBz OAc Japaconitin Acetylbenzoyljapoconin C 2 iH 29 3 N— (OMe) 4 OBz OAc Indaconitin Acetylbenzoylpseudaconin C21H27O2N— (OMe) 4 OBz OAc Pseudaconitin Acetylveratrylpseudaconin C 21 H 2 70 2 N— (OMe) 4 OCOC 6 H 3 (OMe) 2 OAc Bikhaconitin Acetylveratrylbikhaconin C 2 iH 27 ON— (OMe) 4 OCOC 6 H 3 (OMe) 2 OCOC 6 H 4 (OMe) Jesaconitin B enzoylanisy laconin C21H27ON— (OMe) 4 OBz The bases undergo hydrolysis with ease, yielding the acid components and the parent base. The hydrolysis occurs in stages and in the drug itself there will be found not only the specific aconitin, but its various degradation products. It is due to this latter fact that a chemical assay of an aconite preparation or drug has little value as an indication of the 1 Commercial Organic Analysis, Allen, Vol. 7, page 257. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 267 therapeutic efficiency. The degradation products are much less active than the alkaloids themselves. All of the above aconitins are extremely poisonous and if they are suspected, caution should always be observed in testing products physio- logically. Aconitin This alkaloid is the only crystalline base of A. napellus, but is seldom encountered in a state of chemical purity, being accompanied with the other aconin derivatives of the drug. It may be purified by recrystallizing one of its salts, separating the base, and crystallizing it from alcohol or a mix- ture of alcohol and ether. It is readily soluble in chloroform and benzol, somewhat less so in alcohol and ether, slightly soluble in hot water, and only sparingly in cold water and petroleum ether. It is dextrorotatory in alcohol and its salts are lsevorotatory. The purified base melts 197- 198°, but if heated slowly it begins to decompose at 182°, and it will give figures anywhere from this temperature up to 200°. It possesses (a) D = +110 in 3 per cent alcohol. Aconitin produces a tingling and numbing sensation of the tongue, which spreads to the lips and roof of the mouth and may last for hours. Extremely dilute solutions will produce this sensation and it is one of the best tests, though it must be performed with great caution and only in dilute solutions. To make the test the alkaloid should be dissolved in a little dilute acetic acid and the solution adjusted to 1-1000; then an aliquot of this solution may be diluted to 1-100000 with water and 25 mils taken into the mouth, rinsed well for half a minute between the tongue and cheeks after the manner of a mouth wash and then expelled. If at the expiration of ten to fifteen minutes no tingling sensation has appeared a slightly stronger solution, 1-90000, may be used and so on until the sensation is obtained. If the substance under examination is pure aconi- tin, the effect will be readily apparent at the dilution of 1-100000, and the author has tested samples which are potent in a dilution of over a million parts of water. On treating aconitin with nitric acid, evaporating and adding a few drops of alcoholic potash, the characteristic odor of ethyl benzoate is given off. No purple color is obtained on adding the alcoholic potash, but pseudoaconitin is stated to yield a purplish tint. A solution of great dilution when applied to the eye or upper eyelid causes contraction of the pupil, with a sense of heat and tingling. Aconitin gives no color reactions on which any reliance can be placed. It is precipitated by the general alkaloidal reagents and some of the insolu- ble salts form crystals having sharp melting-points and characteristic microscopic forms. The aurochloride is very insoluble and is precipitated 268 ALKALOIDAL DRUGS on adding gold chloride to a solution of aconitin in hydrochloric acid in presence of sodium chloride. This salt when washed and dried in vacuo, may be obtained in three modifications — from alcohol, aqueous alcohol, chloroform and ether, melting 135°, from absolute alcohol, melting 152°, and on recrystallizing the latter from a mixture of chloroform and ether, melting 176°. The precipitate obtained with potassium permanganate is crystalline and may be obtained from dilutions of 1-500; its crystalline form should be compared under the microscope with the crystals obtained with cocain. Hydrastin and papaverin in concentrated solution are said to give crystalline precipitates with permanganate. The periodide is very insoluble. Sparingly soluble precipitates are obtained with potassium iodide and ammonium sulphocyanide. Platinic chloride does not give a precipitate unless the solution is very concen- trated, mercuric chloride, potassium chromate, ferrocyanide, and ferricy- anide give precipitates only in fairly concentrated solutions. Aconitin is a strong base and forms well-defined salts with mineral acids. It is seldom used in the form of a salt, however, nearly always appearing in medicines as the straight alkaloid. It gives di- and tri- acetyl derivatives with acetyl chloride, but no derivatives with acetic anhydride. The hydrolysis of aconitin takes place in two stages, first to acetic acid and benzaconin (picraconitin, napellin, or benzoyl aconin), C34H47NO11+H2O = C32H45NO10+CH3COOH, and then benzaconin is further hydrolyzed to benzoic acid and aconin (C 3 2H45NOio+H20 = C25H4iN07+C6H5COOH). The latter is an amor- phous, hygroscopic alkaloid, soluble in water, chloroform, alcohol and sparingly in ether. Benzaconin is also present in the aconite root, and is readily soluble in alcohol, ether, and chloroform. It does not produce the characteristic tingling of aconitin and is much less toxic. Neutral solutions of aconin are lsevorotatory, the acid solution is dextro. It reduces Fehling's solution and ammoniacal silver nitrate. Japaconitin This alkaloid is obtained from a species of aconite indigenous in Japan, and formerly thought to be A. fisheri, but now considered a distinct species. Japaconitin melts 204-205° and resembles aconitin closely. Its rotation differs somewhat and its hydriodide melts 208-210°, while aconitin hydriodide melts 226°. Its aurochlorides melt 153° (spontane- ous evaporation from chloroform) and 231° (separation from alcohol). In its chemical tests it cannot be distinguished from aconitin. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 269 Indaconitin Indaconitin occurs in A. chasmanthum, a native plant of India. It melts at 202-203° and its rotatory power and that of its salts are some- what less than those of aconitin. It hydrolyzes in two stages, first to acetic acid and indbenzaconin, and then to benzoic acid and pseudaconin. Its chemical and physical behavior is similar to that of aconitin. Pseudaconitin Pseudaconitin differs from the previous bases in containing the vera- tryl group instead of the benzoyl, and yields veratric acid on hydrolysis with alcoholic potash. Its physiological action is more intense than the other aconite alkaloids. It melts 211-212°. The base is dextro- and its salts laevorotatory. The aurochloride forms yellow needles, melting 236-238°. The nitrate with 3 molecules of water is difficultly soluble and melts 185-186°. It gives a purple-red color when subjected to Vitali's test and a similar color when warmed with concentrated sulphuric acid. Veratric acid is soluble in alcohol and ether and only slightly soluble in water, and may be removed from an acidulated solution. It crystal- lizes in prisms containing one molecule of water and melts 178-180°. It is the dimethyl ether of protocatechuic acid. COOH ^NoCHg \/ OCHs Pseudaconin, the basic product of hydrolysis, crystallizes from alcohol, melting 94-95°. Bikhaconitin This alkaloid like the former contains a veratryl group in its mole- cule and yields veratric acid on hydrolysis. It crystallizes from ether in white button-shaped masses composed of concentric rings, differing from its related bases in this respect. It melts 118-123°. Jesaconitin This is an amorphous alkaloid from A. japonicum and contains no acetyl group. On hydrolysis it yields anisic and benzoic acids and aconin. Anisic acid is paramethoxybenzoic acid, readily soluble in ether, alcohol, and hot water, melting 184° C. Lycaconitin Lycaconitin and myoctonin are amorphous bases of A. vulparia. The former is soluble in ordinary organic solvents with the exception of petro- 270 ALKALOIDAL DRUGS leum ether, and only sparingly in water. It is precipitated by Mayers reagent, tannin, bromine water, and iodine, but not by platinic chloride, mercuric chloride, potassium iodide, nor phosphomolybdic acid. Its basic product of hydrolysis is lycaconin, melting 90-92°, soluble in alcohol, chloroform, ether, and benzol and giving a fluorescent solution in water. Myoctonin This base is but slightly soluble in ether, but in other respects closely resembles lycaconitin. It yields lycaconin on hydrolysis. It has a bitter taste but does not produce a tingling sensation. It is a strong poison, however, and is reported to resemble curare in its action. Lapaconitin, Septentrionalin and Cynoctonin These three alkaloids occur in A. lycoctonum, or according to some authorities in A. septentrionale. Lapaconitin melts 205°, septentrion- alin 129°, and cynoctonin 137°. The first mentioned gives fluorescent solutions but the others do not. Lapaconitin is bitter and a heart depres- sant, the others are local anesthetics. Atisin This alkaloid occurs in A. heterophyllum and is not toxic. The drug is employed as a bitter tonic. Atisin forms a colorless varnish melting 85°, readily soluble in water and organic solvents except petroleum ether. It is lsevorotatory and its salts dextro. With sulphuric acid it gives a yellow color gradually becoming red. It is not hydrolyzed by acids or alkalies but apparently forms a new base. Palmatisin Palmatisin occurs in A. palmatum and forms crystals from ether, melting 285°. It resembles atisin in its physiological properties. Aconitic Acid CH 2 — COOH I C— COOH II CH— COOH Aconitic acid, which appears to be a constant constituent of aconite root, is closely related to citric acid in composition. It forms colorless crystals, melting 186° C. (191° Mullikin), soluble in water, alcohol, and ether. Its aqueous solution gives no precipitate when boiled with excess of calcium hydroxide. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 271 M. Pt. and (a) D of final product of hydrolysis CO rt go ■3 co S^ 8 + < 2-, fc< ^ a oos So* 1+ . •a S el ScT "S oo o3 CO 1 + o •S d o co 8+g c3° 45 S3 5= mOS-9 "o O o .9-9 'So c oo 5co -O ^ pq S-o'3 — ■->. o o CO + ||| is 2 " c a - £ a- 9 .5 ° pjCSJ r CO F QCsi'5 3.2C — 1-3 .9 so CO o co r P0 - =§coJ H- 1 3 ill % T " H -9 J^ - o >.. = CO +3 _ X 03 CO Pi O | ►* & ' Oa Aos 3 CO 3+ -^ a o © o3 o3 > °o° ° CO^~> o COt-H IC CO 1-H CO O r^co CO CO CO CO CO CO CO CO J3 3 co "o N " 2"o + -i o *o co fi-s + 1 + -3 |-4 « 2 + -a + -3 o "O 2 o "O OS* 8 '1 £ S o 00 OS ri OS o CO o CO o CO CO O (N (M 1 CO o CO Jj! o CO LO o CO o OS CO o co : 00 CO >j C >i T3 .2*3.9 o fl c O O o *2'§ c cSoC .2g§ lla !"2 'S =3 .9 o ^ O d c u .2*5 -8 lis c2 « C — r. _Z " H - o*S.9 * c S '5 § 5 ^ 30 q d a q j-|H d d d '3 < < *-3 o3 t-3 '-3 '2 c o -o a *-5 'S c c O o m Ph "-3 "S 3 # o '■+3 "3 8 oS '2 o o b3 '2 o +3 o o >> .0 '-j3 "2 C a si 1 G c c o "2 O +3 C3 O ti >> 272 ALKALOIDAL DRUGS The problems which may confront the drug analyst in connection with the aconite alkaloids are as follows: the identification of "aconitin," the determination of the amount present in a mixture, the determination as to whether the amount of alkaloid originally present agrees with that claimed on the label (taking into account the ease with which aconitin decomposes), the question as to the identity of the drug used in compound- ing an extract of aconite and the actual identity of an aconitin. The word aconitin above is written in quotations in order to emphasize the fact that the identity of an aconitin does not necessarily require one to report the exact individual in question. The first three propositions are those requiring the chief consideration of the analyst, the others may occur in rare cases. Special attention must be called to the third proposition above mentioned; it often happens that a manufacturer acts in perfect good faith and makes up his formula in the proper proportions, but in the course of time, and due to the various hands through which a product must pass to the final consumer and the conditions under which it is kept, its potency becomes impaired and the blame is unjustly carried back to the original source. In the general scheme of medicinal analysis aconitin will appear when the solution has been made alkaline and shaken out with petroleum ether and with ether. These two fractions will carry a large proportion of the aconitin, the latter the greater proportion unless the quantity is extremely small. The first suggestion of aconitin will occur when a residue evapo- rated with nitric acid, is treated with alcoholic potash and the character- istic odor of ethyl benzoate is obtained. Cocain will give the same reac- tion, but if this is followed by a physiological test, conducted by rubbing a minute quantity of the residue on the tongue and lips, cocain produces numbness while aconitin will give the characteristic tingling. Follow- ing this a portion of the residue should be dissolved in a small quantity of dilute acid and portions of this solution treated with gold chloride and potassium permanganate, the characteristic forms of the crystals observed under the microscope in comparison with those produced with a known sample of aconitin, and the melting-point of the auxochloride determined. If there is sufficient quantity of the residue and it is not contaminated with other alkaloids it should be crystallized, dried in vacuo, and its melt- ing-point determined. When this test is applied the sulphuric acid should be heated to 160-170° before introducing the capillary tube containing the alkaloid, and the acid rapidly heated until the crystals melt. Unless the analyst is familiar with aconitin he should use great caution in performing the physiological test, and for safety the procedure recom- mended on page 267 ought to be observed. In order to determine the amount of aconitin in a fluid, solid extract, or tincture, the procedure recommended in the chapter on Drug Assays ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 273 can be used to advantage. The residue will be contaminated to a greater or less extent with other bases, and it may be desirable to dissolve the resi- due in dilute acetic acid, make up to a definite volume, and then use aliquots of this in a Squibb test, comparing the activity with that obtained with a sample of aconitin of known purity prepared by the worker him- self. By this means the quantity of pure aconitin in the original product can be calculated. From mixtures with other non-alkaloid-bearing drugs, aconitin may be separated by extraction from an ammoniacal solution with ether, purified by redissolving in acid, separating any acid or neutral principles by the usual solvents and then removing the aconitin with ether from alkaline solution. The therapeutic activity of a mixture, with respect to the aconitin present, can be obtained by performing a Squibb test on a solution of the original substance precisely as described by Taylor's method on page 27. This procedure is about the only one known for estimating aconitin in mixtures with the other alkaloids with which it is dis- pensed. No methods have been evolved for separating aconitin chemic- ally from other bases, and any which might be based on its products of hydrolysis are too uncertain to be considered. Of course the base may be easily separated from morphin by shaking it aut with ether from a solu- tion made slightly alkaline with caustic alkali. The fact that it is resist- ant to permanganate, while quinin, strychnin, and many other bases reduce this reagent, is a point which may be used to advantage in solving this problem and offers an attractive field for investigation. If the amount of aconitin found on analysis does not agree with that claimed, it must not be concluded that the proper quantity was not originally absent. The quantity of acid products of hydrolysis present as well as other basic substances must be determined and the sum total, properly interpreted, used as evidence to substantiate or refute the claim on the label. The identification of the species of aconitin used in the preparation of a medicine requires careful work. Standard preparations specify the use of A. napellus, and as physicians regulate their dosage on the assump- tion that the standard drug with which they are familiar, has been employed, and as it appears that the several " aconitins " vary in thera- peutic efficiency and possibly physiological activity, any variation in the specific drug employed may lead to disastrous results. Hence the drug analyst may be called upon to settle the question as to whether the drug in hand is A. napellus or some other species. The alkaloid must be sepa- rated and carefully purified, and after determining its melting-point and that of its aurochloride, it must be hydrolyzed and both the acid and basic products of hydrolysis identified beyond question. When this is done by referring to the table on page 271 the " aconitin " in hand will be apparent, and when this is determined the drug employed is known. 274 ALKALOIDAL DRUGS BASES OF CEVADILLA AND VERATRUM Cevadilla or Sabadilla seed and Veratrum root possess certain similar physiological properties, especially in relation to their action on the heart, and while there may be no similarity in the chemical composition of the bases, and neither drug possesses an alkaloid in common, unless it be veratridin or cevadin, it is advisable, to avoid confusion, to consider the drugs together. The term " veratrin " has been used for a long time in alkaloidal chemistry and has become so firmly established that, in the minds of many, it is attributed to an individual alkaloid. This is further complicated by the fact that the U. S. and other Pharmacopoeias recog- nize the term, with the amplification that it is "an alkaloid or .mixture of alkaloids," and then proceed to describe its properties, even to defining a specific melting-point. As a matter of fact the so-called " veratrin " is realty a mixture of the bases obtained from the seeds of Cevadilla, the proportions of which must necessarily vary from time to time. The chief component of " veratrin " is cevadin, an alkaloid which has not been found in the rhizome of Veratrum viride or V. album, and which is apparently different in composition from any of the bases occurring in the latter. Hence we see that the term " veratrin," which will prob- ably always persist, does not apply to alkaloids from the genus Veratrum, and account of this anomaly it is expedient to conjointly discuss the bases of these drugs. In this introduction attention must be called to an examination of the bases from Zygadenus intermedius conducted by Heyl 1 and his associ- ates, who extracted from the leaves of this plant, called locally Death Camas, a new base to which the name zygadenin has been given and which, in its chemical properties, resembles cevadin. It differs from the latter, however, in its ultimate composition, which is given as C39H63NO10, and in having (ci) D — 48.2°, while cevadin is inactive. Prof. Kraemer states that the bulbs of Z. venenosum contain veratral- bin, sabadin and sabadinin. CEVADILLA BASES Cevadin, C32H49NO9. Veratridin, Cs^sNOs. (?) Sabadin, C29H51NO8. (?) Sabadinin, C27H45NO8. (?) Sabadillin (Cevadillin) C^HssNOs. (?) The plant Schoenocaulon officinale (Lilacese), growing in Mexico and the West Indies, furnishes the seeds from which these bases are obtained, 1 J. Am. Chem. Soc, 1911, 206; 1913, 258. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 275 and the alkaloidal content varies from 1 to 3 per cent, with cevadin pre- dominating. Tiglic and veratric acid also exist in the drug, either in the free state or in combination. The seeds are not recognized in the U. S. Pharmacopoeia, but they find a place in the Swiss standard, and a method of assay is included therewith. American manufacturers apparently make little use of the drug and from all reports the seeds are used chiefly for preparing " veratrin." The ground seed is used as an ingredient for destroying vermin in the hair. The alkaloidal mixture " veratrin " is a drastic and irritant cathartic and has been employed in articular rheu- matism, ascites, as a cardiac sedative, and externally in superficial neural- gias, sciatica, and some forms of pruritus. It is a dangerous drug for indis- criminate use and will be rarely found in unknown mixtures. Cevadin Cevadin crystallizes from alcohol with 2 molecules of the solvent, which is removed with difficulty when heated to 100° C, but is readily removed with boiling water, and the anhydrous base melts 205-206°. It dissolves in all of the organic solvents except petroleum ether, and its solutions are inactive to polarized light. It is extremely poisonous and has the peculiar property of producing violent sneezing. It gives crystal- line salts with gold chloride, picric acid and mercuric chloride, and an amorphous precipitate with platinic chloride. It yields precipitates with the usual alkaloidal precipitants. The individual color reactions of this base have not been reported. All of the tests described in the literature refer to the mixed bases, and these reactions will be described subsequently. Cevadin is readily hydrolyzed by aqueous and alcoholic alkaline solu- tions. It is first transformed to angelic acid and a new base called cevin. Then angelic acid changes to the isomeric cevadic or tiglic acid, which is partly broken up into acetic and propionic acids, and the cevin forms non-basic resinous products. The products of hydrolysis may be obtained by boiling the base with alcoholic potash under a reflux con- denser, diluting, acidifying, and shaking out the acid products with ether, and then making alkaline and removing cevin by amy] alcohol. The ether solution of the acids is evaporated and the residue distilled, and as the fraction coming over at 180-190° is collected and cooled, it will yield crystals of tiglic acid, melting 64-65°. Tiglic acid is methyl crotonic acid, CH 3 CH=C(CH3)COOH. Cevin obtained on evaporating the amyl alcohol, melts 145° and dis- solves in alcohol and acids, but only sparingly in chloroform, and scarcely ALKALOIDAL DRUGS in ether. It is precipitated by caustic alkalies, but not by carbonates, and reduces Fehling's solution and ammoniacal silver nitrate. Veratridin This is an amorphous base, and its properties are not well known owing to the difficulty of obtaining it pure. It melts at 150° or 180° and forms a fairly insoluble nitrate and sulphate. On hydrolysis it yields veratric or dimethyl protocatechuic acid and a basic product, verin or veratroidin, which bears a close resemblance to cevin obtained from ceva- din. Veratric acid is one of the products of hydrolysis of pseudaconitin and has already beeen described. Sabadin Sabadin is a crystalline base, melting 238-240°. It is precipitated from its solutions by warming with sodium carbonate, and shaking with ether. On subsequent crystallization from alcohol it is only sparingly dissolved in ether. It is claimed to give no color with nitric acid, but dissolves in sulphuric acid with a yellow color and green fluorescence, which soon disappears, and a blood-red to violet shade develops. Sabadinin This base is separated in a similar manner to sabadin which it resembles in some of its properties and color tests thus far studied. It melts 160° and does not produce sneezing. Sabadillin Sabadillin has been reported as occurring in commercial veratrin. It yields tiglic acid on hydrolysis. The above descriptions of the bases show that, with the possible exception of cevadin, the chemistry of this group is still in its pioneer state. From an analytical standpoint we can only consider the alkaloids en masse, because as yet we know little or nothing of the solubilities of the sub- sidiary bases, and there is no scheme for separating them when they occur in the quantity usually available. There are several color tests attributed to the purified residue. Sul- phuric acid dissolves the bases to a yellow solution with a greenish fluores- cence, changing to blood-red and finally to purple. Hydrochloric acid gives a permanent blood-red, and nitric acid a yellow solution, often pink- ish at moment of solution. Sulphuric acid containing furfurol gives a dark-green color becoming violet on warming. ■^ ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 277 These tests, taken in conjunction with the physiological action of the alkaloids (intense sneezing), and the production of the characteristic acids on hydrolysis, furnish the necessary evidence for deciding as to the identity of the bases and the drug from which they are obtained. None of the cevadilla bases give reactions which might confuse them with the opium, Nux Vomica, coca, belladonna, and cinchona bases, for all of which there are certain well-defined tests. There is, however, some likelihood of mistaking a mixed residue from Veratrum viride or V. album for one from Cevadilla, as the former con- tains veratralbin, which resembles cevadin in its properties and gives rise to a series of color reactions similar to those above described. With the exception of veratralbin, most of the Veratrum bases when isolated are but sparingly soluble in ether. However, this property can- not be depended upon for making a separation from alkaline solutions with immiscible solvents, as jervin and probably the other bases are fairly soluble in ether when freshly precipitated. Protoveratrin and pro- toveratridin are but sparingly soluble in ether or chloroform, and portions may still be found in the alkaline solution after shaking out with these solvents. The solubility of the cevadilla bases is such that they are prac- tically all removed by ether from alkaline solution. THE VERATRUM ALKALOIDS Jervin, C26H37NO3. Rubijervin, C26H43NO2. Pseudojervin, C29H43NO7. Protoveratrin, C32H51NO11. Protoveratridin, C26H45NO8. Veratralbin, C^sH^NOs or C32H03NO9. The roots of Veratrum album from Southern Europe and of V. viride, Bunch flower family (Melanthiacese) , from the United States and prob- ably other related species contain these alkaloids. Wright reports ceva- din in the roots of V. viride and possibly veratridin. The two species mentioned are official in the U. S. Pharmacopoeia. V. viride, called the American hellebore, is a native perennial herb, 2 to 7 feet high growing in swamps, wet woods and meadows, closely associated with skunk cab- bage. It produces large bright-green leaves and is a very conspicuous plant in the meadows and swamps. Veratrum is employed medicinally in the form of its extract, but its use is limited and is attended with so much danger that it will seldom be encountered in practice. It is present in small dosage in liver pills mixed with jalap, aloes, gamboge, leptandra, Podophyllum resin, Capsicum, 278 ALKALOIDAL DRUGS croton oil, and calomel. It is a heart depressant and is used in certain aortic conditions. The percentage of total bases in V. viride seems to vary considerably running from .2 to over 1 per cent. In V. album, Wright found over 4 per cent of alkaloids with veratralbin predominating, though he reported but a trace in V. viride, cevadin, and jervin being the chief bases in the latter. Jervin Jervin crystallizes in white acicular prisms containing 2H2O, and on drying at 100° it melts 241°. It is readily soluble in chloroform, less so in alcohol and ether, and almost insoluble in benzol and petroleum ether. It is not hydrolyzed by boiling alcoholic potash. It is a strong base and forms well-defined salts, the acetate and phosphate being easily dis- solved in water, but the hydrochloride, nitrate, and sulphate are only sparingly soluble especially in the presence of the free acid. The less soluble salts may be^ prepared by treating a solution of the phosphate or acetate with the alkali salt of the acid. Jervin gives a yellow color with sulphuric acid, changing to brownish, greenish brown, and on longer standing to green, which finally disappears. Pseudojervin also gives the green shade, but the other Veratrum bases ultimately produce a reddish tint. Sulphuric acid and sugar produce a violet color, changing to blue. This reaction is not very satisfactory, however, as the mixture first becomes dark brown and after a time a vio- let tint appears along the edges and in thin layers, and then gradually turns blue. Froehde's reagent acts in the same manner as sulphuric acid alone. Nitric acid gives a pinkish tint, the solution soon turning orange and then slowly fades. Hydrochloric acid gives a light yellow color. Precipitates are obtained with the common alkaloidal reagents includ- ing tannic acid. Rubijervin Rubijervin crystallizes in acicular prisms containing one molecule of water, and on drying melts 234°. It is somewhat soluble in alcohol, hot chloroform, and benzol, and slightly soluble in ether and petroleum ether. Its salts are much more soluble than those of jervin. It gives a yellow solution with sulphuric acid, turning brownish, reddish brown, and finally purplish. If the brownish-red liquid is diluted with water, the color changes to crimson and passes through several violet and purple shades to deep blue. It is precipitated by the common alkaloidal precipi- tants with the exception of tannic acid and platinic chloride. ALKALOIDS WHICH PROBABLY CONTAIN A PYRIDIN NUCLEUS 279 Pseudojervin Pseudojervin crystallizes in hexagonal plates, melting 304°. It is readily soluble in chloroform, slightly soluble in alcohol and benzol, and practically insoluble in ether and petroleum ether. The sulphate is slightly soluble in cold but readily in hot water, and the hydrochloride is only sparingly soluble in water either hot or cold, but is dissolved in water containing a little free acid. With sulphuric acid it gives the same color tests as jervin, and is precipitated by the same reagents except platinic chloride. Veratralbin This alkaloid is amorphous and melts at 149°. Its salts are amor- phous. It dissolves easily in the ordinary organic solvents. Its color reactions are similar to those obtained with cevadin; sulphuric acid pro- duces a yellow color, changing to orange and blood-red with a greenish fluorescence; nitric acid a fleeting rose tint, the solution becoming pale yellow; dilute hydrochloric acid a rose color. It is precipitated by the common alkaloidal reagents. Protoveratrin This alkaloid, which seems to be the most active of the group, crystal- lizes in microscopic plates, melting 245-250°. It is sparingly soluble in the organic solvents. It gives a green color with sulphuric acid which passes through blue to violet. Hydrochloric and phosphoric acids give a dark cherry red and a butyric odor.- It is not precipitated by tannic acid, platinic chloride, or mercuric chloride, but is thrown down by the other common reagents. It is stated that protoveratrin may be separated from the other bases by treating an acetic acid solution with solid glacial phosphoric acid, fil- tering, and extracting the protoveratrin with ether after rendering am- moniacal. Protoveratridin This base crystallizes in plates melting at 265°. It is insoluble in ether, benzol, and petroleum ether and only to a slight extent in alcohol and chloroform. With sulphuric acid it gives a violet to cherry-red color and with hydrochloric acid a bright red color and a butyric odor. It is not precipitated by platinic chloride or potassium cadmium iodide. An alkaloidal residue consisting of the Veratrum bases will give indi- cations of its identity by evolving a butyric odor when treated with acids at the same time its color reactions are determined. The mixed bases 280 ALKALOIDAL DRUGS will give negative tests with the reagents employed for the other well- known alkaloids. Farr and Wright have evolved a method for separating jervin from its accompanying bases. The alkaloidal residue is dissolved in 2 per cent acetic acid, filtered, a few crystals of potassium nitrate added, shaken until dissolved and the solution allowed to stand. The crystals of jervin nitrate which deposit on standing are filtered, washed with a little water and then treated with chloroform and a little dilute ammonia. The jervin dissolves in the solvent and may be obtained by evaporating. If the analyst can obtain sufficient material, this test will furnish the best evi- dence of the presence of Veratrurn "in a medicinal preparation. CHAPTER IX ALKALOIDS WITH NO PYMDIN NUCLEUS AND THOSE OF UNKNOWN COMPOSITION COLCHICIN, C 16 H 9 (NHCOCH3)(OCH 3 ) 3 (COOCH3) The meadow saffron, Colchicum autumnale L. (Liliacese), contains the alkaloid colchicin and probably some of its degradation products. The parts of the plant used commercially are the bulbous root, called the corm, and the seed. The alkaloid is present in amounts varying from 0.2 — 0.5 per cent. Colchicum extract and the alkaloid colchicin have long been used for relieving gout and rheumatism, and should always be looked for in prepa- rations recommended for these ailments. Wine of colchicum is exten- sively employed in some localities, and one of the most widely advertised proprietaries is a globule containing colchicin dissolved in methyl salicylate. Colchicum extract is combined with Hyoscyamus, colocynth, and calomel, and also with aconite. Colchicin is often combined with salicylates in liquid form, also with potassium iodide, digitalin, Phytolacca, codein, quinin, and opium. Colchicin is the methyl ester of colchicein or acetotrimetbylcolchi- cinic acid, and on heating with mineral acids it is readily split up into methyl alcohol and colchicein. The latter, on heating with hydrochloric acid, lose* an acetyl group as acetic acid, and then three methyl groups as methyl chloride, leaving colchicinic acid, CioHiiN(OH) 3 (COOH). Col- chicein has the composition CisH^NHCOCHsXOCHsMCOOH). Colchicin is a weak base and one of the few yellow alkaloids, resembling berberin in this respect, but differing from it in being completely removed from its solutions even when acid, by chloroform. As usually obtained it is a resinous mass which melts with decomposition at about 140-145°. In its crystalline form it melts 120°. It is readily soluble in alcohol and water, and quite readily in chloroform and benzol, but is difficultly soluble in ether and practically insoluble in petroleum ether. Its aqueous solu- tion is lsevorotatory. Its solution in dilute acids gives precipitates with most of the alkaloidal reagents except platinic chloride. In aqueous solu- tion chlorine and bromin water give yellow precipitates which dissolve in ammonia with an orange color. 281 282 ALKALOIDAL DRUGS Colchicin dissolves in concentrated sulphuric acid to a yellow solution, and on adding a drop of nitric, the color changes to green, blue, violet, wine red, and finally green; addition of concentrated sodium hydroxide in slight excess then gives an orange red. It dissolves in nitric acid with a deep purple or bluish color. It gives a yellowish-green solution with ammonium vanadate; a green color soon fading with sulphuric acid and bichromate; and with formaldehyde sulphuric acid the crystals become reddish and the liquid yellow. An aqueous solution of colchicin heated on the steam-bath for one-half hour with 5 drops of 20 per cent hydro- chloric acid and subsequently treated with 3 to 5 drops of ferric chloride solution will develop a green color, and on cooling and shaking out with chloroform the latter will separate either yellowish or permanganate red, depending on the amount of colchicin present. If the colored liquids are too opaque, the mixture must be diluted with water. The red tint will not appear unless the amount of colchicin be over 2 milligrams. It combines with chloroform to form opaque needles with a mother- of-pearl luster. This substance loses chloroform when heated to 100° C. or when warmed with water It is now being marketed as a medicinal product. Colchicin also forms a crystalline compound with ether. A non-poisonous substance giving many of the reactions for colchicin has been found among the normal constituents of beer, being apparently derived from .hops. Putrefying cadavers yield substances which bear a close resemblance to colchicin, and might easily be mistaken for this alka- loid in toxicological w T ork. Colchicein, its first degradation product, forms shining needles with JH2O. The water may be driven off at 140-150° and the anhydrous substance then melts 160-170°. It is slightly soluble in cold water, readily soluble in alcohol and chloroform, and almost insoluble in ether and benzol. On account of the ease with which colchicin is hydrolyzed, it is probable that colchicein is present to a greater or less extent in most of the colchicin residues obtained in analytical work. It is soluble in alkalies and alkali carbonates, and with acids forms yellow solutions. Colchicin may be readily detected in the mixtures in which it is com- monly employed on account of its solubility in chloroform from a neutral or acid solution. It will seldom if ever be found combined with berberin, and if the latter is present, the greater part will remain in solution until the final shake-out with alcohol — chloroform according to the regular scheme. When colchicin occurs combined with Hyoscyamus, aconite, opium, codein, or quinin it will be completely separated from all of the other alkaloids except possibly narcotin, narcein, and papaverin, when the acid solution of the crude alkaloids is shaken out with chloroform. The presence of the above mentioned opium alkaloids in the residue will be at once apparent on adding formaldehyde-sulphuric acid. When col- ALKALOIDS WITH NO PYRIDIN NUCLEUS 283 chicin occurs mixed with salicylates, the salicylic acid will of course appear in the chloroform residue from an acid shake out; if the residue is then dissolved in chloroform and the solution shaken out with sodium hydroxide, the salicylic acid will be completely removed. In some cases before sub- jecting a colchicin residue to the color tests and other reactions for its identification, it will be advantageous to purify the alkaloid by precipi- tating, as the iodine compound as described under the assay of colchicum. The preliminary treatment of the samples in which it is desired to find colchicin, should follow the usual lines customarily employed when working with organic mixtures. An exception should be made, however, in the case of the globules of colchicin and methyl salicylate. The medica- ment should be washed out with petroleum ether, poured into a separatoiy funnel, and then shaken out with dilute hydrochloride acid to remove the colchicin. The alkaloid can be recovered from the acid by agitation with chloroform. Quantitative Methods. — The separation and determination of col- chicin in wine of Colchicum and in Colchicum preparations generally may be carried out according to the procedure described under the assay of colchicum. If the sample is a liquid, 25-50 mils should be taken as a sample, the bulk of the alcohol evaporated on the water-bath and the residual solution transferred to a separator with water and petroleum ether, then made slightly acid with hydrochloric acid and the colchicin extracted with chloroform and purified. After removing the crude col- chicin the acid aqueous liquid can be set aside and later treated with excess of ammonia and any atropin, aconitin, codein, quinin, or morphin determined by shaking out with the proper solvents. If salicylates are present the procedure must be modified by dissolving the crude colchicin in chloroform, transferring to a separator and shaking out two or three times with dilute sodium hydroxide to remove the salicylic acid. The alkaline liquid is then washed once with fresh chloroform, the latter added to the chloroform containing the colchicin, the whole filtered and evaporated. If the sample is a pill or tablet 10-20 units should be ground in a mor- tar and extracted four to five times with alcohol, the alcoholic solution filtered, 20 mils water added and after evaporating most of the alcohol, the assay continued as described above. ASSAY OF GLOBULES OF COLCHICIN AND METHYL SALICYLATE For assaying globules of colchicin and methyl salicylate, a dozen or more of the globules should be pierced and the contents poured into a weighing tube. A weighed quantity of the liquid is then transferred to a separator with petroleum ether, and the mixture shaken out with dilute 284 ALKALOIDAL DRUGS hydrochloric acid until the colchicin is entirely removed, four extractions in general being sufficient. The colchicin may then be recovered from the acid by shaking out with chloroform. It it is desired to determine the amount of methyl salicylate in the petroleum ether solution, after the acid treat- ment, it is transferred to a flask of about 200 mils capacity, 50-100 mils of alcoholic potash added, and the contents boiled under a reflux condenser until the methyl salicylate is entirely saponified. The alcohol is then evaporated, the solution poured into a separator, the salicylic acid set free by mineral acid and shaken out with ether from which solution it may be determined by titration with standard alkali, or by removing with sodium bicarbonate and precipitating with iodine, the details of which are described under salicylic acid, page 676. The factor for methyl salicy- late is 1.1014. THE XANTHIN BASES Xanthin, C5H4N4O2. Caffein, C 8 Hi N4O 2 . Theobromin, C 7 H 8 N 4 02. Theophyllin, C 7 H 8 N 4 02. Hypoxanthin, C5H4N4O. Guanin, C5H5N5O. Adenin, C5H5N5. These bases occur naturally in some or all of the following : tea, coffee, cocoa, Paraguay tea or mate, guarana, and cola. Tea leaves contain all except theobromin and guanin, the caffein com- prising from 2 to 2J per cent. Cocoa beans (Cacao seed) contain from 1 to 4 per cent of theobromin and a small amount of caffein-: Coffee leaves contain 1 to 3 per cent of caffein alone, and the beans from .5 to 2.5 per cent caffein alone. Paraguay tea contains from 1 to 2 per cent of caffein alone. Guarana contains as high as 5 per cent of caffein alone. Cola contains from 2 to 3 per cent of caffein and a little theobromin, about .02 per cent. The last four bases are found in the seeds, buds and roots of a large number of plants, and also occur widely distributed in the animal king- dom, having been observed in almost all the organisms of the higher animals and are probably decomposition products of nuclein. They are deriv- atives of purin, C5H4N4. Their constitutional characteristics have been developed by Fischer. Purin is also the mother substance of uric acid. This latter is a tri- oxypurin and from it purin may be prepared. ALKALOIDS WITH NO PYRIDIN NUCLEUS 285 The constitution of purin is seen by the following structural formulae: Derivatives of both forms are known. H N C— NH HC CH C— N \ N or H N C=N HC \ CH / C— NH w The most important member of this group is camein, and it will be found very extensively in medicinal preparations. Theobromin present in cocoa will also be met with to some extent, but the other bases will seldom be found except in meat products and preparations of this type. Xanthin / c \ HN C— NH \ CH OC C— N \ N / H 2-6 dioxypurin Xanthin occurs naturally in tea leaves, the juice of the beet, shoots of lupine and barley, and is not liable to be met with to any extent in drug analysis. It is usually present in meat products and it is in preparations of this type that it might be found. It separates from its aqueous solution as a white powder, and when heated it decomposes above 150° without melting, and evolves carbon dioxide, ammonia, and hydrocyanic acid. It is almost insoluble in cold water, and very little soluble in hot water; insoluble in alcohol and ether. It is a weak, monoacid base, has acid properties and unites with bases to form salts containing two equivalents of the metal. These salts are very unstable, being decomposed by carbon dioxide and water. Xanthin is soluble in caustic alkalies, but is precipitated by adding an acid or even passing carbon dioxide gas through the mixture. It is dissolved by warm ammonia, which distinguishes it from uric acid. Mercuric chloride pre- cipitates xanthin in very dilute solutions. Cupric acetate produces no precipitate in the cold, but on heating a flocculent apple-green precipitate 286 ALKALOIDAL DRUGS is produced. An ammoniacal solution of xanthin gives precipitates with zinc chloride, calcium chloride, and lead acetate. On treatment with potassium chlorate and concentrated hydrochloric acid it is oxidized to urea and alloxan, and on evaporating the solution to dryness and exposing to the fumes of ammonia a bright pink color develops. This is known as the murexide reaction. Xanthin dissolves in hot nitric acid without evolution of gas. On careful evaporation of the solution a yellow residue remains, which turns reddish yellow on addition of caustic potash or soda, and on subsequent heating becomes reddish violet. If ammonia be substituted for the fixed alkali, no violet coloration is obtained. This test distinguishes xanthin from uric acid, which gives the characteristic murexide reaction when similarly treated. If solid xanthin be sprinkled on a solution of caustic soda mixed with bleaching powder, each particle becomes surrounded with a dark ring or scum, which rapidly becomes brown and then disappears. Xanthin may be converted to theobromin by treating its lead salt with methyl iodide and heating to 100°. C 5 H 2 N402Pb+2CH3l = C 5 H2N40 2 (CH3)2+Pbl2 It may be converted to caffein by heating it in aqueous alkali with methyl iodide. C 5 H 4 N402+3CH3l+3KOH = C5HN402(CH 3 )3+3KI+3H20 In the general run of drug assaying it is doubtful if one would be called upon to make a quantitative estimation of xanthin bases other than caffein and theobromin, but in case it becomes necessary to determine these bodies, attention is directed to the following method: Xanthin Bases. (Schittenhelm's Method.) 1 — Dissolve from 3 to 5 grams of the extract in 100 mils of water, transfer to a large evaporating dish, and add 500 mils of a 1 per cent solution of sulphuric acid. Heat on the water-bath for four or five hours, finally evaporating to a volume of from 75 to 100 mils, neutralize with potassium hydroxide, using litmus paper as an indicator. Transfer to a beaker, add 15 mils of a 15 per cent solution of sodium bisulphate and from 15 to 20 mils of a 15 per cent solu- tion of copper sulphate, cover with a watch-glass, and let stand overnight. Filter and wash with dilute copper sulphate. Return the precipitate to the original beaker, add sodium sulphide, acidify with acetic acid and warm on the steam-bath. Filter hot and wash with hot water. Treat the filtrate with 10 mils of 10 per cent hydrochloric acid and evaporate it on the steam-bath to about 10 mils. Filter and wash, make ammoniacal 1 Bull. 90, U. S. Dept. of Agriculture, page 129. ALKALOIDS WITH NO PYRIDIN NUCLEUS 287 and add in slight excess a 3 per cent solution of ammoniacal silver nitrate. Let stand overnight, filter, wash out all ammonia carefully, and determine nitrogen in the precipitate. The result is the nitrogen of the xanthin Caffein O / C \ /CH 3 CH 3 N C— N<^ CH C— N^ \ N / CH 3 1-3-8 Tri Methyl Xanthin or 1-3-8 Tri Methyl — 2-6 Dioxypurin Caffein was discovered in the coffee berry in 1820, and it occurs in this plant in combination with citric and tannic acids. It occurs also in tea, guarana, Paraguay tea, cola nut, and the seeds of cacao. The base is present in the plants in the free state to some extent, but it also occurs combined with acids and probably also in the form of glucosides. This renders a simple, complete extraction of caffein from drug extracts dif- ficult if not impossible, and it becomes necessary to treat the products with acids or alkalies in order to effect hydrolysis or separation from the plant acids. In medicinal preparations, particularly of the headache mixture type, caffein will be found in the alkaloidal form. Guarana extract will be met with both in the liquid and solid form. Cola preparations are found quite extensively on the market, but extracts of coffee or tea will be met with only sparingly. Caffein and preparations of guarana and cola occur in products which are designed to cause stimulation and in tonics for the nervous system. Headache mixtures nearly always contain caffein, and it will be found in diuretic compounds and in some heart tonics. It is used to a large extent as an ingredient of popular beverages. Caffein and caffein-containing drugs will be found in products of the following types: Elixir celery compound, containing celery seed, coca, kola, and often Viburnum prunif olium ; elixir kola compound, containing celery seed, kola, and coca; kola wine and kola cordial; elixir celery and guarana; elixir acetanilid compound, containing acetanilid, caffein, sodium bromide, codein, and Gelsemium; elixir migraine, containing acetanilid, caffein, and sodium bromide; liquid headache mixtures contain caffein together with acetanilid, acetphenetidin, antipyrin, bromides, and often aromatic spirit of ammonia; pills are marketed containing extract of kola and 288 ALKALOIDAL DRUGS extract of guarana, but most of the caffein bearing-preparations of this kind contain the alkaloid caffein; cardiac pills containing caffein, Digitalis, glonoin and Strophanthus, and sometimes codein; compressed tablets for relieving headache contain caffein and acetanilid, and often acetphenetidin or antipyrin, or some combination of these substances with bromides and sodium bicarbonate; migrain tablets contain caffein and camphor monobromate; neuralgic tablets contain caffein with Hyos- cyamus and morphin. Caffein is a feeble base, but forms definite compounds with mineral acids, which, however, are easily broken up in aqueous solutions. It crystallizes in fleecy masses of long, flexible, white crystals, having a silky luster, odorless, with a bitter taste, and permanent in the air. Its reac- tion is neutral to litmus. It is soluble at 15° C. in 80 parts of water, 33 parts of alcohol, seven parts of chloroform, and about 550 parts of ether. It is readily soluble in boiling water, chloroform, alcohol, amyl alcohol, and benzol, less sol- uble in ether, and only slightly in carbon bisulphide and petroleum ether. It does not evaporate with the vapor of water, and undergoes no appreci- able change at 100° C. except that its water of crystallization, 1 molecule, is expelled. At 100° it volatilizes very gradually, and at a high temper- ature it sublimes unchanged. At 229° C. it melts to a colorless liquid. It readily undergoes decomposition when boiled with limewater, but decom- position is insignificant when boiled with magnesium oxide and water, and no change occurs with lead oxide. It may be oxidized by nitric acid or by hydrochloric acid and potas- sium chlorate, the products of oxidation including amalic acid, which on subsequent treatment with ammonia goes over to murexoin, which has a brilliant purplish-pink color. Uric acid and oxidizing agents give allo- xanthin, C8H 6 N408, and with ammonia this latter is converted into murex- ide, NH4C8H4N5O6. Theobromin and xanthin give a reaction similar to caffein. The purple coloration in case of caffein and theobromin is decolor- ized by caustic alkali, but that due to uric acid is changed to blue. An aqueous solution of caffein is not precipitated by potassium-mer- curic iodide test solution. This is also true of theobromin. A neutral aqueous solution is not precipitated by a solution of iodin and potassium iodide, but in, an acid solution, caffein is precipitated quantitatively. Its solution in water (1 to 200) gives an abundant precipitate on adding a satu- rated solution of mercuric chloride. More dilute solutions give less immedi- ate precipitate. Tannic acid gives a precipitate soluble in excess of the reagent. Potassium-bismuth iodide precipitates caffein from moderately dilute solutions after a time. Phosphomolybdic acid gives a yellow pre- cipitate, soluble in warm sodium acetate solution, and depositing free caffein on cooling. Platinic chloride and hydrochloric acid added to a ALKALOIDS WITH NO PYRIDIN NUCLEUS 289 concentrated solution gives an orange-red precipitate, soluble in 20 parts of cold and smaller amounts of warm water, crystallizing again on cooling. The solubility of caffein in water is increased by the presence of cer- tain substances, such as sodium bromide, sodium benzoate, sodium cin- namate, sodium salicylate, and antipyrin. Caffein may be completely removed from an acid aqueous solution by shaking out with chloroform. Caffein is removed from an aqueous solution by charcoal, but when dissolved in chloroform the solution may be shaken with charcoal with- out any absorption of the base. Lead sulphide will carry down caffein when precipitated from solutions clarified by lead acetate. Caffein may be separated from theobromin by treating the mixed alka- loids with cold benzol, in which theobromin is practically insoluble. QUANTITATIVE DETERMINATION OF CAFFEIN The methods for the determination of caffein in fluid extracts of guarana and kola have already been described. In all cases where caffein is present wholly or partly in the form of a drug extract caution must be observed that the caffein compounds are thoroughly broken up so that the alkaloid will be completely extracted. Many methods for the estimation of caffein in tea or coffee have been published and most of them are unsatisfactory and unreliable. The Association of Official Agricultural Chemists require the use of the modi- fied Stahlschmidt method in official work for determining the caffein in tea, and the Gorter method for coffee. Modified Stahlschmidt Method. — Weigh 3.125 grams of the finely powdered sample into a 500-mil flask, add 225 mils of water (this volume will shrink to about 200 mils by boiling), attach a reflux condenser and boil for two hours. Add 2 grams of dry basic lead acetate and boil ten minutes more. Cool, transfer to a 250-mil graduated flask, fill to the mark, filter through a dry filter, measure 200 mils of the filtrate into a 250-mil graduated flask and pass hydrogen sulphide through it to remove the excess of lead. Make the solution up to the mark and filter through a dry filter. Measure 200 mils of this filtrate into an evaporating dish and concentrate to about 40 mils. Wash the concentrated solution with as little water as possible into a small separatory funnel and shake out four times with chloroform, using 25, 20, 15, and 10 mils, respectively. If any emulsion forms, break it up with a stirring rod and run the separated portions of chloroform through a 5-c.m. filter paper into a small, tared Erlenmej^er flask. Evaporate off the chloroform on the steam-bath, or recover the chloroform by attaching the flask to a condenser and dis- tilling to a small volume. Dry the fine, white crystals of caffein to con- 290 ALKALOIDAL DRUGS stant weight at 75° C. Test the purity of this residue by determining nitrogen and multiplying by the factor 3.464. Gorter Method. — Moisten 11 grams of finely powdered coffee with 3 mils of water, allow to stand thirty minutes and extract with chloroform for three hours in a Soxhlet extractor. Evaporate the extract, treat the residue of fat and caffein with hot water, filter through a cotton plug and moistened filter paper and wash with hot water. Make up the filtrate and washings to 55 mils, pipette off 50 mils and extract four times with chloroform. Evaporate the chloroform extract in a tared flask, dry the caffein at 100° C, and weigh. Transfer the residue to a Kjeldahl flask with a small amount of hot water and determine nitrogen. To obtain the weight of caffein multiply the result by 3.464. From most of the alkaloids with which it may occur combined, caffein may be separated by taking advantage of the fact that it can be removed from acid solution by chloroform, the other bases being retained. This, however, is not the case when acetanilid, acetphenetidin, and antipyrin are present, and special methods of separation have been provided which will be found on pages 795, 837 and 857. In the case of liquid preparations containing caffein in the form of base, or when present in the form of kola, guarana, coffee or tea; or com- bined with alkaloids such as cocain, morphin, strychnin, and atropin; weigh or measure accurately the sample, transfer to a medium sized evapo- rating dish, add ammonia and digest for four hours and evaporate over steam-bath until no further diminution in volume takes place. Treat the residue with alcohol, warm, then cool and decant washings into another evaporating dish. Repeat the process four or five times if necessary should the residue contain much gummy material. Add water to the alcoholic solution, and then evaporate over steam-bath until all alcohol is driven off. Transfer to a separatory funnel, washing out dish with water and render the solution slightly ammoniacal. Shake out with four successive portions of chloroform using 15 to 20 mils each time. The chloroform now contains all the caffein and if any other base is present this is also dissolved, morphin of course to a very limited extent. Now shake out with three successive portions of 2 per cent sulphuric acid, which will remove all the bases except caffein and preserve the acid solution. Filter the chloroform solution into a tared dish, washing the funnel, filter paper, inside of funnel, and stem of funnel with chloroform and evapo- rate to dryness at 100°. If the residue of caffein is colored, or con tarns grease or has much odor it should be dissolved in dilute hydrochloric acid, transferred to a flask, and an excess of strong solution of iodine in potassium iodide added. Rotate the flask until the caffein iodin compound agglom- erates and let stand overnight. Filter, wash precipitate once with iodin solution, discarding washing and not attempting to remove the last por- ALKALOIDS WITH NO PYRIDIN NUCLEUS 291 tion of precipitate from flask in which precipitation was made. Pour a solution of sulphurous acid over filter or place a crystal of sodium sul- phite on the filter, add water and 1 to 2 mils of hydrochloric acid and run the liquid into the flask in which the original precipitation was made; wash filter paper with sufficient of the liquid to decompose the iodine compound and then place filter paper in flask and heat for ten to fifteen minutes over the steam-bath. Cool, filter into separatory funnel, wash out flask three times with water. Render ammoniacal and shake out three times with 15- to 20-mil portions of chloroform. Run chloroform through filter into a tared dish, using precautions of washing with chloro- form as above mentioned. Evaporate to constant weight at 100°. In some instances a dye stuff will stay with the caffein, but this may be removed by shaking the chloroform solution with a strong solution of sodium bisulphite. The other alkaloids having been separated by the above mentioned method by shaking out with acid can now be determined. The details and precaution to be observed are described under the particular alkaloid in question. Theobromin HN C— N< CH OC C— N^ 3-7 dimethyl 2 CHa -6 dioxypurin or 3-7 dimethylxanthin Theobromin occurs in cacao beans combined with malic acid. It also occurs in small amounts in kola nuts. Theobromin is a diuretic and a nerve stimulant and its compounds with benzoates, salicylates, etc., have a limited use in medicine. Urocitral is a mixture of molecular amounts of theobromin and sodium citrate; agurin of theobromin and sodium acetate ; uropherin B of theobromin and lithium benzoate; uropherin S of theobromin and lithium salicylate. Iodotheobromin consists of 40 per cent theobromin, 21.6 per cent sodium iodide and 38.4 per cent sodium salicylate. Chocolate is used in some preparations in order to make them palatable and the analyst will probably find theobromin here. Its presence or absence will also be valuable evidence in determining whether many of the so-called " chocolate-coated tablets " are actually covered with choco- late or only iron oxide encased in sugar. 292 ALKALOIDAL DRUGS Theobromin crystallizes in the anhydrous state and forms microscopic needles, melting 329-330° C. in a closed tube. When heated exposed to the air it sublimes without melting at 290-295° C. It is soluble in amyl alcohol, fairly soluble in chloroform, alcohol and water when hot, slightly soluble in benzol, ether, cold water, and alcohol, and insoluble in petroleum ether and carbon tetrachloride. It is soluble in acids and precipitated by alkalies, but soluble in excess of caustic alkali or ammonia. It is wholly extracted by chloroform from its solutions in caustic alkalies. It is a weak monoacid base, neutral, and its salts are decomposed by water. It does not combine with alkyl iodides. It possesses acid prop- erties and forms definite salts, the sodium and barium salts having been studied. Theobromin gives a white crystalline precipitate with mercuric chloride, sparingly soluble in water and alcohol. It forms with silver nitrate a definite and insoluble compound, C7HsN402AgN03, which is only sparingly soluble in water and may be dried unchanged at 100° C. With solution of sodium phosphotungstate it gives in acid solution a yellow precipitate. This may be mixed with sodium carbonate or mag- nesium oxide, dried, exhausted with chloroform and the theobromin recovered. When boiled with concentrated barium hydrate solution or alkalies it .yields no product similar to caffeidin. Theobromin gives with oxidizing agents and ammonia the same color reactions as caffein. If 0.05 gram theobromin is treated with 3 mils water and 6 mils sodium hydroxide solution, and to the mixture 1 mil ammonia and 1 mil 10 per cent silver nitrate added, solidification takes place on shaking, the mass will liquefy at 60° C, and on cooling a transparent jelly results which will withstand the action of light for a week or more. Caffein does not give this test, and theobromin may be separated from caffein by precipi- tating it as the silver nitrate compound. Estimation of Theobromin Method of Decker as Modified by Welman. — Boil 5 grams of powdered cacao seeds which have not been freed from fat, or 10 grams of chocolate, for an hour in a large Erlenmeyer flask under a reflux con- denser with 5 grams of magnesium oxide (calcined magnesia) and 300 mils of water. Let the flask stand upon a boiling water-bath until the sus- pended matter has settled and then pour the hot, supernatant liquid through an asbestos filter. Wash the residue in the flask twice with ALKALOIDS WITH NO PYRIDIN NUCLEUS 293 200-mil portions of boiling water. Pour the clear liquid through the same asbestos filter. It is advisable to use a water pump in filtering. Boil the residue again for an hour under a reflux condenser with 2 grams of magnesium oxide and 300 mils of water, decant, and filter. Mix all the filtrates with ignited sea sand and evaporate to dryness upon the water- bath. Reduce the residue in a hot mortar to as fine a powder as possible, extract three or four times in an Erlenmeyer flask for thirty minutes with 70-mil portions of chloroform and filter hot. Distill each portion of chloro- form upon the water-bath and use the solvent again. Pass a gentle stream of air through the flask, until there is no odor of chloroform. Dissolve the residue in 10 per cent ammonium hydroxide solution and filter. Evapo- rate the nitrate to dryness in a weighed platinum dish, dry the residue to constant weight and deduct the weight of ash from the weight of total alkaloids. Caffein and theobromin can be separated by cold benzene, theobromin being soluble only to the extent of 1 : 100,000, whereas caffein passes easily into solution. Method of Kunze. — Heat 10 grams of powered cacao-seeds twenty minutes with 150 mils of 5 per cent sulphuric acid. Filter while hot and add excess of sodium phosphomolybdate to the warm filtrate. Set aside for a day and wash the precipitate upon a filter with 5 per cent sulphuric acid. Decompose the moist precipitate, containing theobromin, in a large beaker with barium hydroxide. Precipitate excess of barium hydroxide by carbon dioxide, evaporate the mixture to dryness upon the water-bath and extract the well-dried residue under a reflux condenser with boiling chloroform. Evaporate the chloroform solution in a weighed flask and dry the residue to constant weight. This residue consists essentially of theobromin mixed with some caffein. This gives the weight of total alka- loids. To estimate theobromin, dissolve the residue in water containing ammonia, add excess of N/10 silver nitrate solution in known quantity and heat to boiling. This will precipitate the silver salt of theobromin (CyHyN-iCbAg- IIH2O) free from caffein. Determine excess of silver in an aliquot portion of the measured filtrate by titration with N/10 sulphocyanate solution. Caffein does not form a silver compound. To determine the corresponding quantity of theobromin, multiply the weight of silver in the precipitate by 1.66. Determination of Theobromin and Separation from Caffein. (Brun- ner and Lewis.) — The substance, such as coffee, kola, cocoa, or mate, is boiled for thirty minutes, with 500 mils of water, under a reflux con- denser. The solution is then precipitated with freshly prepared lead hydroxide, until colorless, heated again to boiling for fifteen minutes, and filtered. The residue is washed twice with 500 mils of water, the filtrate and washings being reduced, by evaporation, to a volume of 500 mils. Carbon dioxide is led through the boiling solution, the precipitated lead 294 ALKALOIDAL DRUGS carbonate is filtered off, and the filtrate evaporated on the water-bath, after adding some quartz sand. The residue obtained is extracted for eight hours with ether in a Soxhlet apparatus. After distilling off the ether, the residue is boiled out three times with 50 mils of water, and filtered, when cooled to 50° C. On evaporating and drying at 80° C, the two alkaloids are obtained as a white ash-free product. Separation. — The mixed alkaloids are dissolved in hot water, pre- cipitated with silver nitrate, the precipitate redissolved in 2 to 3 mils of ammonia, and the solution warmed to expel the latter, dust and a strong light avoided. After cooling to 30° C, the precipitated silver-theobromin is collected on a weighed filter, washed, and dried at 100° C. The sub- stance has the formula CyHyAg^CV The filtrate is treated with sodium chloride, filtered and evaporated on the water-bath. The caffein is extracted from the residue with ether, the latter is evaporated, and the alkaloid dried at 100° C,. and weighed. Theophyllin CH 3 — N / c \ oc I C— NH \ CH C— N CH 3 1-3 dimethyl 2-6 dioxypurin Theophyllin is an isomer of theobromin and occurs in tea leaves. It is also made synthetically and marketed under the name of Theocin. It is a powerful diuretic, and is also used in cardiac affections and dropsy. It crystallizes in plates, melting at 264-268° C, somewhat soluble in cold but readily in boiling water, soluble in chloroform, little soluble in alcohol, and insoluble in ether, It is a weak monoacid base and forms readily soluble potassium, sodium, and ammonium salts, and is not removed readily by solvents from alkaline solution. It forms a crystalline hydrochloride, nitrate, chloroplatinate, auro- chloride, and mer euro-chloride. When evaporated with chlorine water, theophyllin yields a scarlet residue which is changed to violet on addition of ammonia. ALKALOIDS WITH NO PYRIDIN NUCLEUS 295 The silver derivative, CyH^AgN^, is obtained as an amorphous pre- cipitate on adding silver nitrate to an aqueous solution of theophyllin. It crystallizes from hot ammonia, and dissolves readily in nitric acid. The methyl derivative, C7H7MeN4C>2, prepared by heating the last substance with methyl iodide and methyl alcohol, melts at 229°, and is identical with caffein. When a solution of theophyllin in sodium hydroxide is treated with a solution of 0.5 per cent sulphanilic acid and 5 per cent hydrochloric in water, followed by a few drops of 0.5 per cent solution of sodium nitrite, a red coloration is produced. Caffein and theobromin do not respond to this reaction. It gives a precipitate with tannic acid soluble in excess of the reagent. Theophorin is a mixture of molecular amounts of theophyllin and sodium formate. Hypoxanthin or Sarcin C-oxypurine This body differs from xanthin only in possessing one less oxygen atom. It occurs in both the animal and vegetable kingdoms and in the former is probably a decomposition product of nuclein. It is present in the seeds of the lupine, barley, mustard, black pepper, vetch, gourd, alfalfa, cloves, in wheat bran, potatoes, sugar-beets, and tea. It forms microscopic needles decomposing without melting at 150° C. Little soluble in water; scarcely soluble even in hot alcohol and insoluble in ether. It possesses both acid and basic properties and combines with one equivalent of an acid and two of a base. On oxidation with potassium chlorate and hydrochloric acid it gives alloxan and urea the same as xanthin. It forms crystallizable salts with acids and the microscopic appear- ance of the nitrate and hydrochloride are characteristic. The silver oxide compound, Ag20CoHoN40. is formed as a gelatinous precipitate on adding ammonio-nitrate of silver to an ammoniacal solu- tion of the base. It is insoluble in ammonia, unless used in great excess, and it dissolves with difficulty in boiling nitric acid; 1.10 sp. gr. On cooling a compound of the formula, CsHs^OAgNOs, separates in crystals having a characteristic form under the microscope. The character of silver nitrate compound permits the separation of hypoxanthin from other bases of the group. On treatment with hydrochloric acid and zinc it gives a ruby-red coloration on the addition of caustic soda in excess. Adenin gives a red color under similar conditions. 296 ALKALOIDAL DRUGS Guanin 2-amido 6-oxypurin Guanin occurs in the seeds of several leguminous plants, in those of the gourd, in the sugar-beet and in cane sugar. It crystallizes from ammonia in needles or small plates which are insoluble in water, alcohol, or ether. It is neutral and dissolves in both acids and alkalies to form salts in which it functionates on the one hand as a diacid base and on the other as a dibasic acid. It may be heated to 200° without change. Guanin is distinguished from xanthin and hypoxanthin by its insolu- bility in hot dilute ammonia. It gives a highly insoluble precipitate with picric acid. It gives precipitates with potassium bichromate and potassium ferri- cyanide, differing thereby from xanthin and hypoxanthin. Its hydrochloride and nitrate have characteristic forms when viewed under the microscope. Adenin 6-amidopurin Adenin occurs in the pancreas of the ox, in tea, and in sugar-beets. It is formed during the decomposition of nuclein by sulphuric acid. It crystallizes in long needles with one molecule of water. The anhy- / drous alkaloid melts without decomposition at 360-365° C. It is readily soluble in hot water, little soluble in cold water or alcohol, and insoluble in ether and chloroform. It is neutral and forms salts with one equivalent of an acid or a base. Adenin does not give the ordinary color reactions of the xanthin bases, but resembles hypoxanthin in giving a red color when treated with hydro- chloric acid and zinc and subsequently with an alkali. It gives precipitates with potassium ferrocyanide and ferricyanide after acidulating with acetic acid. With chromic acid it gives a crystalline compound, and with copper sulphate an amorphous grayish-blue pre- cipitate. Adenin is very completely precipitated by copper sulphate in presence of a reducing body and by using sodium thiosulphate and operating in cold solutions it may be separated from hypoxanthin. t!!arnin, C7H8N4O3, Vernin, CieB^oNgOg, Pseudoxanthin, C4H5N5O, Heteroxanthin, C6H6N4O2, andr^Baraxanthin, C7H8N4O2, are of no special interest to the drug chemist. With the exception of caffem, theobromin, and theophyllin, all of the xanthin bases are insoluble in ether and chloroform. They all give white precipitates with phospho-molybdic acid, mer- ALKALOIDS WITH NO PYRIDIN NUCLEUS 297 curie chloride, and ammoniacal lead acetate, and guanin and adenin are very perfectly precipitated by picric acid. A general reaction of the xanthin bases (including uric acid) is their precipitation from ammoniacal solutions by ammonio-nitrate of silver, as a gelatinous compound of the base with agentic oxide. The xanthin com- pound contains C5H4N402Ag20. The precipitates are usually insoluble in ammonia, unless concentrated and used in large excess, but to ensure complete precipitation excess should be avoided. On treating the pre- cipitates with dilute nitric acid of 1.10 sp. gr., they are converted into compounds of the bases with silver nitrate, xanthin forming CsH^^C^AgNOs. These compounds are well-defined crystallizable bodies insoluble in water, and, in the cases of Irypoxanthin, carnin, adenin, and episarkin, insoluble in nitric acid of the above strength, even on boiling; or, at any rate, crystallizing out rapidly on cooling. Guanin, carnin, adenin, and episarkin are stated by G. Salomon to behave similarly but, according to J. L. W. Thudichum, the silver nitrate compound of guanin dissolves tolerably easily in hot dilute nitric acid, and is only very gradu- ally deposited on cooling. The compounds of xanthin, heteroxanthin. and paraxanthin remain in solution after cooling, which difference of behavior permits of their separation from the bases previously mentioned. The bases are all completely reprecipitated as their silver-oxide compounds on neutralizing the nitric acid solution by ammonia. Heteroxanthin and paraxanthin may be separated from xanthin by taking advantage of the limited solubility of their sodium salts in caustic soda, and from each other by utilizing the sparing solubility of the hydrochloride of heteroxanthin. Mixtures of the bases with Fehling's solution and hydroxlyamin hydro- chloride added all give precipitates except caffein and theobromin. CHEMISTRY OF THE BOTANICAL INDIVIDUALS CONTAINING THE XANTHIN BASES Phytochemical studies of some of the caffein-bearing drugs have demonstrated that in the plant the caffein is combined with acidic or phenolic-like bodies. These combinations are termed tanoides by some authors. In coffee the combination is one of caffein with chlorogenic acid and potassium, and in kola and guarana the caffein is united respec- tively to kolatin and guaranatin. The caffein in these combinations can- not be obtained by extraction directly with chloroform, but only after treatment with an aqueous solution. Potassium-caffein chlorogenate can be obtained by percolating raw coffee with absolute alcohol. The first portion of the percolate is diluted with 96 per cent alcohol until a precipitation of shiny material is complete. 298 ALKALOIDAL DRUGS The clear liquid is then mixed with the remainder of the percolate, the alcohol recovered in vacuo and the residue evaporated to a syrup in the water-bath. The potassium-caffein chlorogenate is allowed to crystallize and the crude material recrystallized from 60 per cent alcohol. In order to obtain pure chlorogenic acid the substance is dissolved in water, enough sulphuric acid added to convert the potassium into sulphate, the liquid extracted with chloroform to remove the caffein, and then allowed to evaporate spontaneously until the chlorogenic acid crystallizes. The pure substance melts 206-207°, slightly soluble in water and ethyl acetate, readily in alcohol and acetone, practically insoluble in ether, chloroform, and carbon bisulphide. It gives a grass-green color with ferric-chloride, and a yellowish red with potassium hydroxide, darkening on exposure. KOLA Considerable work has been done on the constituents of this drug. Knebel first reported kolanin in 1892. * Hilger in 1892 and 1893 verified Knebel, the body being apparently a glucoside splitting up under the influ- ence of heat or ferments into glucose, caffein and tannin. Carl Schweitzer continued and verified this work in 1895. Schlotterbeck published a monograph on cola in 1894. A partial analysis of cola was made by Knox and Schlotterbeck in 1895. 2 A short historical summary of the above work is given by Knox and Prescott. 3 Knox and Prescott investi- gated the cafTein compound in cola and determined that it was a cola tan- nate of caffein instead of a glucoside. The question arose as to whether the tannin in this compound was identical with the free tannin in cola. Preliminary investigations seemed to show that there was a difference. They finally established the identity of the tannin combined with the caffein and the free tannin existing in cola nuts. They do not agree with Knebel' s claim that the tannin of the cola is an oxidation product of cola red. 4 Gorris isolated from fresh nuts .3 to .4 per cent of a new constituent which he calls kolatin. 5 After a critical review of the constituents Perrot and Gorris conclude that only three well-defined bodies have been isolated from the drug, namely, caffein, theobromin and kolatin. The last named has been obtained from fresh seeds in small white-colored crystals of the formula CsHgC^. It is slightly soluble in water and its solution has the property of dissolving caffein and theobromin, as solutions of sodium and salicylate do; under suitable conditions of high oxidation, it yields cola 1 Apoth. Zeit., 7, 112. 2 P. A. P. A., 1895, 334. 3 P. A. P. A., 1896, 136. * P. A. P. A., 1896, 136, 1897, 131 * Phar. Zeit., No. 11, 1906, 118; P. A. P., A. 1906, 770. ALKALOIDS WITH NO PYRIDIN NUCLEUS 299 red. Kolanin is only a mixture, probably mechanical, of cola red and caffein. It is not glucosidal and cannot be considered one of the con- stituents of the seeds. On drying the nuts kolatin disappears. 1 Gorris and Chevalier have studied the physiological activity of kolatin prepared from fresh cola nut and find that injected intravenously into warm-blooded animals it increases the energy of cardiac contractions and slightly raises the blood pressure. It is to a certain extent antagonistic to caffein both as regards the action on the muscles and on the central nervous system. Hence the powdered seeds sterilized before they were dried have a physio- logical action different from that of the dried seeds in which the kolatin no longer exists, it having been converted into cola red. 2 Konig gives the following analysis of cola nut: Per Cent H 2 11.23 Nitrogenous material 8 . 34 Caffein 2.09 Theobromin 0.023 Fat 0.52 Starch 42.72 Gums and sugar 18 . 94 Kola red 1.29 Cellular material 10 . 80 Ash 3.13 99.08 KOLATIN Kolatin-caffein has been isolated from the fresh sterilized kola nuts. In the dry state this body does not give up its caffein to chloroform, but if dissolved in warm water the caffein may be removed by chloroform, leaving the kolatin, which crystallizes on cooling. It may be purified by recrystallization out of ether. It forms white microscopic needles, melt- ing at 148°, slightly soluble in water, very soluble in ethyl and methyl alcohol, acetic acid, acetone, slightly soluble in ether and insoluble in chloroform and petroleum ether. It has no action on polarized light. With ferric chloride it gives a green color, becoming red with ammonia or sodium hydroxide and violet with sodium carbonate. It is not an acid, it does not neutralize bicarbonates. It reduces ammoniacal silver nitrate in cold, and Fehling's solution on heating, and is precipitated by lead acetate, potassium bichromate, and copper acetate. It is rapidly transformed to a red amorphous body by the action of light, heat, or an oxidizing ferment, and continually loses weight when dried in a vacuum over sulphuric acid or in an oven at 105°. 1 Pharm. Gorris, 1908, 31 and P. A. P. A., 1908, 228 ■ P. A. P. A., 1908, 414. 300 ALKALOIDAL DRUGS It has not been settled definitely whether the kola nut contains a com- pound of kolatin and caffein similar to the chlorogenate of caffein and potassium, or whether the kolatin compound is a complex glucoside. Kolatin is a body of the catechin group described as decomposing into phloroglucin and protocatechuic acid. Chlorogenic acid acts in similar manner. Kola nuts contain an oxydase which acts on kolatin during drying and produces a " red." The dried nuts, representing the commercial drug contain no kolatin, hence this body will not be found in galenical prepa- ration. ERGOT ALKALOIDS Ergot of rye is the sclerotium of Claviceps purpurea (Hypocreacese), a fungus having two distinct periods in its life history, an active and a resting stage. During the latter it forms a compact mycelium or sclero- tium, which replaces the flowers and the grains of rye. It is gathered by hand or by threshing. It deteriorates with age, particularly when powdered. The drug is produced in Russia, Spain, and Germany. Spanish ergot consists usually of large grains, having a fine appearance) but often not so active as that from other sources. It has a heavy odor which is increased when the powder is triturated with warm alkali hydroxide. Ergot has a specific action on the uterus and is an indispensable drug to the obstetrician. The extract is an important commodity, and many modifications are offered, usually under some copyrighted name suggest- ive of the derivation of the product, and claiming to be more or less free from the inert and irritating substances present in the drug. Sterilized aqueous decoctions of the active ingredients free from fat and other princi- ples are dispensed in sealed tubes for hypodermic use. In this form of package the potency of the drug is retained over a considerable period. Solid extract of ergot is a component of emmenagogue formulas which contain, in addition, some or all of the following drugs; extract of cotton root bark, black hellebore, savine, aloes, ferrous sulphate, and oil of penny- royal. It is also combined with Digitalis and quinin; with lupulin, atro- pin, Scutellaria, and zinc bromide; with gallic acid and hydrastin; with Cannabis sativa, etc. Liquid mixtures contain ergot with Caulophyllum, savine, and water pepper; and occasionally some of the drugs mentioned above. The chemical composition of ergot has been the subject of much study. In the aggregate the discovery of a large number of the constituents has been reported, and confusion has resulted owing to the numerous desig- nations given to the same body by different workers. It is tolerably certain that three bases at least are present — ergotinin, C35H39O5N5, the ALKALOIDS WITH NO PYRIDIN NUCLEUS 301 hydrate of which, ergotoxin, C35H41O6N5, has a powerful physiological action; tyramin or hydroxyphenylethylamin, OH • C6H4 • CH2CH • NH2, an important heart stimulant; and isoamylamin, (CHs^CHCHfeCB^NKfe. The drug also contains a coloring substance which is of great assistance to the analytical chemist for purposes of identification. Ergot contains about 30 per cent of fixed oil and fat. Ergotinin, C35H39O6N6 Ergotinin crystallizes in long needles which, when subjected to the temperature of a bath at 210° and further heated, sinter, darken, and melt up to 229°. It is soluble in alcohol, acetone, ethyl acetate, and chloro- form; moderately soluble in ether, benzole, and amyl alcohol, and nearly insoluble in petroieum ether. When boiled in dilute phosphoric acid ergotoxin phosphate is formed. Ergotinin is removed from alkaline solutions by ether. A solution of this alkaloid in sulphuric acid gives with ferric chloride an orange-red color, becoming deep red, with a blue to bluish green margin. A solu- tion in glacial acetic acid, to which ferric chloride is added and cautiously treated with sulphuric acid, will yield a violet zone at the point of contact. Ergotinin is probably the cornutin of some investigators. Ergotoxin, Hydro-Ergotinin, C35H41O6N5 Ergotoxin is a light white powder, which begins to soften at 155° and melts gradually at 162-164°. It is more soluble in organic solvents than ergotinin, though only slightly in ether, and more sensitive towards alka- loidal reagents. When boiled with acetic anhydride a molecule of water is split off and ergotinin results. Solutions of both ergotinin and ergo- toxin are fluorescent. Para-hydroxyphenylethylamin. Tyramin, OH • C 6 H 4 • CH 2 CH 2 NHj This base can be extracted from ergot extracts only with great dif- ficulty on account of its ready solubility in water. It may be removed by amyl alcohol from a concentrated solution made alkaline with sodium carbonate. When crystallized from alcohol it forms hexagonal leaflets, melting 161 \ It is soluble in 10 parts of boiling alcohol, somewhat less soluble in boiling water, and still less in boiling xylol. When treated with methyl iodide, a quaternary iodide is obtained which is identical with the methiodide of hordenin. Barger and Dale isolated an active principle from ergot, the relative abundance of which suggested that it was wholly or partly produced by micro-organisms. They isolated the base by means of Kutscher's 1 1 Z. Unters. Nahr. Genussm., 1905, 10, 528; 1906, 11, 582. 302 ALKALOIDAL DRUGS method and obtained the silver compound. The hydrochloride, picrate melting 220-230°, and picrolonate melting 250° were prepared, and the base gave Pauly's reaction with p-diazobenzenesulphonic acid. The investigators consider that the new base is /3-iminazolylethylamin. Ergot contains an undetermined substance which has been called ergoxanthein or ergot-yellow by Wengell, and which is of importance in identifying the drug. It may be separated by treating an evaporated alcoholic extract of the preparation with water, filtering, washing the undissolved material with water, and extracting the filtrate first with chloroform and then with ether, the latter removing the ergoxanthein. It is an orange-yellow substance soluble in alcohol, ether, benzol, ethyl acetate, amyl alcohol, acetone, and carbon bisulphide. A residue of the separated substance is practically insoluble in water and chloroform. It gives a dark-orange color with concentrated nitric acid. It is precipi- tated from alcoholic solution by basic lead acetate and phosphotungstic acid, but not by barium chloride. Its alcoholic solution becomes blood red when rendered strongly ammoniacal and gives a characteristic absorp- tion spectrum. This test is probably the same as tnat described by Schmidt, who designates as sclererythrin a pigment existing in the outer coat of the ergot. It is an amorphous red powder, subiimable, soluble in alcohol and glacial acetic acid, slightly in ether, and insoluble in water and petroleum ether. It dissolves in ammonia, alkali hydroxides, carbonates, and bicarbonates with a red or red-violet color. An ethereal solution colors sodium hydrox- ide a deep red and the colored solution shows characteristic absorption bands. Sclererythrin gives blue-violet precipitates with solutions of cal- cium hydroxide, barium hydroxide, and lead acetate. Iron chloride pro- duces a deep-green precipitate, and chlorine or bromine a lemon-yellow. In working with mixtures an evaporated alcoholic extract of the sample is treated with tartaric acid and digested with alcohol, the alcohol filtered, evaporated, and the residue treated with ether. The ether is filtered into a separator and shaken with 1 to 2 c.c. of cold saturated sodium bicarbonate solution, which becomes violet if sclererythrin is present. If the ether solution be shaken with ammonia, the alkaline liquid sepa- rated and precipitated with basic lead acetate, the precipitate will color a cold saturated borax solution a red-violet color. ALKALOIDS OF THE CALABAR BEAN Physostigmin, C15H21N3O2. Physovenin, C14H18N2O3. Eseramin. The drug yielding the above mentioned alkaloids is the ripe seed of Physostigma venenosum (Fabacese), commonly known as Calabar Bean. ALKALOIDS WITH NO PYRIDIN NUCLEUS 303 The plant is a tall creeper and the seed is contained in long pods, two or three kernels occurring in each. The fallen seeds are collected by the natives and used by the medicine men in their ordeal tests, from which these seeds have derived the name of " ordeal bean." The drug is official in the several pharmacopoeias, but it is probable that the seeds from other species of Physostigma are sometimes substi- tuted for P. venenosum in the preparation of medicinal products. The drug is rarely used in medicine, but physostigmin salicylate and sulphate are employed in tablet form and usually unaccompanied by other agents. An extract of the drug is sometimes combined with belladonna, colocynth, and Podophyllum. Physostigmin is dispensed with pilocarpin and is often used in veterinary practice for colic in horses. The alkaloid may be anticipated in remedies used in traumatic tetanus, strychnin poisoning, muscular rheumatism, spinal menengitis, torpid constipation, and chronic bronchitis. It is a powerful myotic. Physostigmin Physostigmin, also known as eserin, crystallizes from a mixture of benzol and petroleum ether in prisms melting 86-87°. It is dimorphous, the modification melting 105-106°. Both modifications are lsevorotatory to the same degree (— 60.3° in methyl alcohol, and three molecules of dex- trose. They also report a sitosterol-rf-glucoside, C33H36O6, melting 280.5°, sitosterol, C27H46O, melting 135-136°, (a) -27.3° in chloroform; stig- masterol, C30H50O; sarsapic acid, C4H20(COCH)2, melting 305°, palmitic, stearic, behenic, oleic, and linolic acids, and potassium nitrate. The total quantity of matter extracted bjr alcohol was equivalent to about 1.25 per cent of the weight of the root. They conclude by stating that commercial smilacin, the smilasaponin of V. Schulz, is a mixture of a small amount of sarsasaponin with indefinite amorphous products. 1 Chem. Soc. Trans., 1914, 105, 201. 328 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Quillaja. (Soap Bark) Quillaja saponaria is a large tree indigenous to Chile and Peru. The bark, which is removed in large pieces and deprived of its periderm or other layer, is the official drug. The bark of Q. paeppigii is sometimes substituted for the official drug. Soapbark is the principal source of the commercial saponin, but it finds a place in medicine as a substitute for Polygala senega. Quillaic acid, C19H30O10, is precipitated by neutral lead acetate. It may be separated from an aqueous extract of the bark, or from medicinal mixtures by precipitating as the lead compound, decomposing the latter by hydrogen sulphide in the presence of water which dissolves the quillaic acid, filtering, concentrating nearly to dryness, adding hot absolute alco- hol, and then chloroform to precipitate the coloring matter. On filter- ing and allowing to stand the glucoside separates. It is soluble in alcohol and water, but does not dissolve in ether. It gives a dark-red color with sulphuric acid. When purified by baryta or the acetyl method any toxic properties it may have had apparently disappear, but its chemical reac- tions are unchanged. This may be due to the fact that the crude material occludes some sapotoxin, though the latter is supposed to be soluble in presence of neutral lead acetate. Quillaja saponin is not precipitated by neutral lead acetate and will be found in the filtrate from the precipitation of quillaic acid. It is a toxic substance and differs from quillaic acid by giving a yellowish color with sulphuric acid, changing slowly to reddish. It is soluble in water and alcohol. Senega. Snakeroot The root of Polygala senega (Polygonacese) is a drug indigenous to the United States, and is a popular remedy for croup and diseases of the bronchial passages. It possesses expectorant and diuretic properties, and will therefore be found in preparations intended for chronic catarrh, croup, bronchitis, pneumonia, asthma, rheumatism, dropsy, and amenorrhea. An extract of the root is the form in which this drug is dispensed. It is usually combined with ipecac or squill in liquid mixture and to those will often be added Cimicifuga racemosa (Black cohosh), wild cherry, tartar emetic, and licorice. Other combinations will contain in addition to senega, white pine bark, wild cherry, squill, ipecac, Sanguinaria, opium, potassium nitrate, and methyl salicylate, tar, wild cherry, and verba santa; squill, aconite, Grindelia, guaiac, ammonium carbonate, and bromides; ammonium chloride, squill, and opium; and in some tablet combinations with Hyoscyamus, licorice, tolu, cubeb, ipecac, and ammonium chloride. Senega contains two saponins which are similar to those present in GLUCOSIDES 329 Quiliaja bark. Polygalic acid is precipitated by neutral lead acetate, and gives a ruby-red color with concentrated nitric acid, finally becoming yellow, and yellowish red; it gives a red to violet with concentrated sul- phuric acid. It is slightly soluble in chloroform and from an acid solution is removed to a slight extent by that solvent. Senegin is the sapotoxin and is analogous to the Quiliaja sapotoxin. It gives a yellow color with nitric acid. Methyl salicylate is present in the drug and apparently increases with age. Preparations of which senega is a component will often indicate the drug by the presence of this ester. Senega saponin, which consists probably of a mixture of polygalic acid and senegin, is used sparingly as a remedial agent. Saponaria officinalis. Soapwort While the root of this plant usually constitutes the drug, the entire herb is sometimes used in the form of a decoction. The root may be used as an alterative in the place of sarsaparilla. Its chief use is in venereal and cutaneous diseases, but it is also employed as a diuretic and diaphoretic. The mixed glucosides resemble the crude saponin obtained from Quiliaja. They produce sneezing and are soluble in water and hot alcohol, separating from the latter on cooling. Rosenthaler and Strom x in reporting an investigation of Soapwort saponin assign the plant to the Gypsophilse. As this genus is close to the Saponaria3 and both are in the Caryophyllacese family the results of this research may be inserted at this point. On heating the saponin with 3 per cent sulphuric acid till a portion of the liquid gave no precipitate on further heating, the precipitated pro-sapogenin melted 207° on crystal- lizing from alcohol, and gave a semicarbazone, melting 241°. The pro- sapogenin when heated under pressure with 2 per cent sulphuric acid gave C24H34O5, melting 267-268°, (a) D = +90.86° in alcohol at 18° C. This substance was insoluble in water, but dissolved in organic solvents. Its semicarbazone melted 259-260°, and on oxidation with alkaline perman- ganate it yielded assymetric dimethylsuccinic acid, melting 130-131°. The spikenard, Aralia racemosa, and wild sarsaparilla, Aralia nudi- caulis, are two drug plants which may be mentioned in connection with this group, though their chemistry has never been the subject of research. The rhizome of the spikenard furnishes the drug, and it is used as a gentle stimulant, diaphoretic, and alterative in chronic rheumatism, syphilis, and cutaneous affections. Certain well-known syrups and liquid mixtures contain the extract of spikenard with horehound, San- guinaria, wild cherry, comfrey, and Inula helenium (elecampane); also 1 Arch. Pharm., 1912, 250, 290. 330 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS with morphin, white pine bark, sassafras, wild cherry, Sanguinaria, and balsam poplar buds. Aralia nudicaulis is a gentle stimulant and diaphoretic and is some- times substituted for Sarsaparilla. A closely related plant, Ginseng, Panax quinquifolium, furnishes a drug which though employed to a slight extent only in this country, is exported to China in enormous quantities. The wild plants have become so scarce and the demand for the drug so enormous that properly managed ginseng plantations are sources of great revenue to the owners. Ginseng seems to possess the alterative and diaphoretic characteristics of other saponin-containing drugs. Caulophyllum thalictroides. Blue Cohosh The root of the blue cohosh (Berberidacese) is a valuable uterine tonic drug and is used to a considerable extent in so-called " Female Remedies," where it is usually combined with Helonias, Viburnum opulus, V. pruni- folium, Aletris, and Mitchella. These mixtures are prepared in the form of elixirs, cordials, wines, and tablets. A partially purified solid extract, is called caulophyllin. Emmenagogue compounds are composed of caulo- phyllin, ergot, savine, Polygonum punctatum (water pepper), and other drugs commonly used for the purpose. Power and Salway * have made an exhaustive study of the drug and their results are summarized as follows: An alcoholic extract of the ground material, when distilled in a current of steam, yielded a small amount of a pale yellow essential oil. From the alcoholic extract, the following definite compounds were isolated: (1) A crystalline alkaloid, Ci2Hi 6 ON 2 (m.p. 137°; (a) D — 221.6°), which has been identified as methylcyt isin ; the pier ate melts at 228°. (2) A crystal- line glucoside, caulosaponin, C54H88O17, 4H2O (m.p. 250-255°), which yields a deca-aceytl derivative, C54H7sOi7(CO • CH3)io, melting at 135-140° and on hydrolysis is resolved into caulosapogenin, C42H66O6 (m.p. 315°), and dextrose. Caulosapogenin yields a teTra-acetyl derivative, C42H62O6 (CO -0113)4, melting at 120°, and a diacetyl derivative, C42H640e(CO- CH3)2, melting at 160-162°, from which a c^stalline monosodio-deriva- tive, C42H630eNa(CO -0113)2, was prepared; it yielded, furthermore, a tetrabenzoyl derivative, C42H620e(CO • CeHs)^ melting at 288°, and a mono- methyl ether, C42H6505(0 • CH3), which melts at 235°. (3) A new crystal- line glucoside, caulophyllosaponin, C66H104O17 (m.p. 250-260°; (a)z>+ 32.3°), which yields a deca-acetyl derivative, C66H 9 40i7(CO-CH3)io, melting at 155-160°, and on hydrolysis is resolved into ^aulojJ ayllias&Ro- genin^. C56Hs809(m.p. 315°) and arabinose. Caulophyllosapogenin yields 1 Trans. Chem. Soc, Vol. 103, 1913, p. 191. GLUCOSIDES 331 a hexa-acetyl derivative, C56H 8 209(CO-CH 3 )2, melting at 160-162°, and a dimethyl ether, C56H 8 607(0-CH 3 )2, which melts at 240-242°, and has (a)z>+43.6°. (4) A phytosterol, C27H46O (m.p. 153°). (5) Citrullol, C2sH4602(OH)3. (6) A mixture of fatty acids, consisting of palmitic, stearic, cerotic, oleic, and linolic acids. The alcoholic extract also con- tained a quantity of sugar, which yielded d-phenylglucosazone (m.p. 210°), and comparatively small amount of resinous material. The above-mentioned methyl cytisin, C12H16ON2, represents the alka- loid previously obtained by J. U. Lloyd 1 and designated "caulophylline," but he did not succeed in crystallizing the base, and its composition was not determined. The compound designated by the present authors as caulosaponin, C54H88O17, 4H2O, is undoubtedly identical with a crystalline glucoside first obtained by J. U. Lloyd 2 and termed by him "Leontin," although the formula deduced from its analysis was not correct. Chamaelerium luteum. Starwort or False Unicorn This plant, also known as Helonias, belongs to the Melanthacese and is one of our indigenous drugs. It is often confused with Aletris farinosa, the star grass or true unicorn root. The two drugs are often gathered and mistaken for each other by collectors. Helonias bullata is a closely allied plant and belongs to a monotypic genus. The root possesses tonic and diuretic properties, and its extract is usually one of the constituents of the widely exploited remedies for troubles of the female reproductive organs. The Viburnum Compound type of preparations contain Chamaelirium, Aletris, Viburnum opulus, and pruni- folium, Mitchella repens (Squaw vine) and Caulophyllum thalictroides. Some of the mixtures will lack one or more of these drugs, but this is the general type. Tablets for leucorrhea, known as Helonias astringent, con- tain Chamselirium, Hyoscyamus, Opium, Hamamelis, tannic, salicylic and boric acids, alum, thymol, and eucalyptol. The root contains a saponin-like substance which, when separated, forms a powder of the appearance of acacia, readily soluble in water and hot alcohol but not in other organic solvents. The other constituents of the drug have not been described. Aletris farinosa. Star grass. True Unicorn-root Aletris farinosa (Liliaceae) may well be included at this point because of its confusion with the previous plant. Aletris occurs in uterine tonics of the type mentioned under Chamaeli- rium. The chemical constituents of the drug have never been studied. 1 Proc. Amer. Pharm. Assoc, 1893, 41, 115. 2 Drugs and Medicines of North America, Vol. II, 1887, p. 151. 332 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Its recognition in medicinal mixtures can be accomplished with certainty only by examining microscopically the insoluble portions, and noting any characteristic tissues, which of course must be compared with slides obtained from authentic specimens of Aletris. The presence of a saponin-containing drug is apparent by the frothing of the solution during the manipulation of the mixture while performing an analysis. If the preparation is a liquid, and an alcohol determination is in progress, the frothing and bubbling will often cause considerable inconvenience after the bulk of the alcohol has passed over, and may neces- sitate a redistillation of the distillate. In the systematic scheme of analysis there will be more or less saponin dissolved out by the alcohol and subsequently taken up by water. The presence of the saponin will seriously interfere with the extractions of alkaloids and other principles by immiscible solvents because of the emul- sion formed. This difficulty may be overcome either by shaking out with Prolius mixture or by adding basic lead acetate. Most of the saponin-like substances, with the exception of small amounts of polygalic and quillaic acids, will be left in the aqueous solu- tion after the extraction with immiscible solvents. If it is desired to separate these substances and subject them to characteristic tests, the above-mentioned solution, the original mixture, or an aqueous decoction obtained from the sample may be employed. The saponin is first extracted in a crude state and then purified. The solution is acidulated if alkaline, and then neutralized with magnesium carbonate and 20 grams or a pro- portionately less amount of ammonium sulphate are added and 10 mils of phenol (carbolic acid) ; after shaking, the phenol solution is separated and shaken with 50 mils of water and 100 mils of ether with the addition of alcohol if necessary to prevent emulsification; the aqueous layer is drawn off and allowed to dry in a desiccator. The residue is then washed with acetone or ether and after decanting the liquid, the residue is ready for testing. If dextrins are present they should be first removed by con- centrating the solution to 20 mils and adding 100-120 mils of 95 per cent alcohol; after standing thirty minutes the mixture is boiled on the water- bath, filtered, the alcohol evaporated and the residue made up to 100 mils and treated as above. Another procedure consists in treating the solution with lead sub- acetate and centrifuging, decomposing the precipitate with hydrogen sul- phide in the presence of water, filtering, evaporating, extracting the resi- due with ether, and then dissolving the residue in water, filtering, and evaporating. Of course, if the aqueous solution contained sulphuric or other strong asids or their salts, the neutralized mixture must first be treated with barium chloride to remove them, otherwise their presence GLUCOSIDES 333 would seriously interfere with the evaporation of the nitrate from the hydrogen sulphide treatment of the lead precipitate. The saponin residue can then be subjected to identity tests. It should be divided into fractions by dissolving in water and evaporating 3 to 4 mils for the tests with concentrated sulphuric acid, nitric acid and Froehde's reagent. Portions of the aqueous solution may be treated with the salts of the heavy metals, gold and mercuric chlorides, ammoniacal silver nitrate, ferric chloride, permanganate and potassium ferricyanide, which are reduced, and with alkaline copper. The hemolytic test is applied with a suspension of red-blood corpuscles prepared by washing sterile, defibrinated animal blood by centrifuging three times with physiological salt solution, and when the solution is clear removing 5 mils of the red corpulsces and diluting with 100 mils of the salt solution. A portion of the latter, well mixed, is treated with the saponin solution, which will cause hemolysis, recognized by the reddening of the solution due to the dissolved hemoglobin, and at the same time the cloudy suspension becomes clearer. A negative reaction does not necessarily mean the absence of a saponin-like body because the separation and puri- fication of these bodies appears to change their physiological action, and furthermore it appears that those of the saponin class possess in the nat- ural state the most pronounced action on the blood. The aqueous solution may be further tested by adding hydrochloric acid to a strength of 2.5 per cent and then heating on the steam-bath until the solution ceases to foam. The pro-saponins thus formed are shaken out with ethyl acetate, the solvent washed free of acid, filtered through charcoal and evaporated. The residue should give an orange to cherry- red color with concentrated sulphuric acid, which on standing changes to violet; and its solution in dilute soda should foam on shaking. No very reliable methods have as yet been evolved for estimating the saponins. The relations of the sapogenins to the sugars is not well under- stood, and any quantitative estimation would probably be based upon these products of hydrolysis. Korsakoff 1 describes a method for determin- ing saponins in plants which might be made applicable to liquid medicines and to decoctions prepared from solids. The plant is completely dried, pulverized finely and treated with 60 per cent alcohol. After filtration, the alcohol is distilled off and the residue evaporated with calcined mag- nesia, the magnesia cake is pulverized, exhausted with boiling 80 per cent alcohol, filtered, and the filtrate precipitated with ether. The precipitate is dissolved in dilute sulphuric acid and hydrolyzed by heating for one hour in an autocalve to 100°. The liberated sapongenin is washed with water until neutral, dissolved in absolute alcohol, the solution evaporated to dryness and the sapogenin weighed. From the weight, the correspond- iComptesrend., 1912, 155, 844. 334 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS ing weight of the saponin can be calculated provided the analyst knows the proportion of sugar and sapogenin in the original saponin. Carlifanti and Marzocchi x recommend the following method for determining saponin in emulsions: 100 mils of the emulsion are diluted with an equal volume of water and 400 mils of 95 per cent alcohol added gradually with agitation, the mixture being shaken frequently during two hours and allowed to stand twenty-four hours. The supernatant clear liquid is filtered through linen and the residual oil extracted with 60-65 per cent alcohol, and this extract also filtered and added to the first filtrate. The whole is neutralized with sodium carbonate and concentrated to 100 mils. A slight excess of phosphoric acid is added and saccharin and aromatic substances removed with ether. The residual aqueous liquid is treated with 20 grams of ammonium sulphate, and shaken out with several successive portions of 9 mils each of phenol. The phenol solu- tion is shaken with a mixture of 100 mils of ether, 30 mils of water and 5 mils of alcohol and after twenty-four hours the aqueous solution is sepa- rated, evaporated on the water-bath, the residual saponin washed with acetone, dried, and weighed. ARBUTIN Arbutin is a glucoside which occurs in the leaves of a number of dif- ferent species of plants. Certain evergreen plants whose leaves are official drugs contain arbutin and their medicinal value is probably depend- ent in part at least to its presence. UvaUrsi syn., Arctostaphylos Uva Ursi (Ericaceae), bearberry or upland cranberry, and Chimaphila umbel- lata (Pyrolacese), pipsissewa or princess pine, are the two official drugs characterized by arbutin, and Kalmia latifolia (Ericacese), mountain laurel, non-official, also contains the glucoside. Arbutin is present in the leaves of other plants of the same families. It occurs in Vaccinium Vitis Idsea ( Vacciniacese) , mountain cranberry or whortleberry, an ever- green shrub whose leaves might be mistaken for the Uva Ursi. UVA URSI This drug is astringent and tonic, especially in those diseases affect- ing the urinary organs, hence it may be expected in remedies designed to alleviate gleet, nephritis, catarrh of the bladder, incontinence of urine, etc. An extract of the drug is dispensed in popular form, and it is commonly combined with buchu, juniper berries, cubeb, and nitrous ether in the form of fluid extract buchu compound. It will be found in elixirs in the same combination, and with matico and Hydrangea. It is also present in some of the methylene-blue compounds, and potassium acetate or 1 Boll. Chim. Farm., 1911, 50 , 609. GLUCOSIDES 335 nitrate and Eupatorium may be added to the above-described combi- nations. PIPSISSEWA— CHIMAPHILA UMBELLATA Pipsissewa is an astringent, alterative, tonic, and diuretic drug, and is often substituted for Uva Ursi in remedies designed for the urinary tract. Its extract is used in chronic rheumatism and nephritis. It is combined with Stillingia in fluid extract stillingia compound, in which is also included Bikukulla canadensis, Iris, Sambucus, prickly ash berries, and coriander. Elixirs and syrups of this general composition will be encountered. Chimaphila maculata, the spotted wintergreen, is an evergeren plant which grows in the same localities as the above and is often erroneously called pipsissewa. KALMIA LATIFOLIA The extract of mountain laurel has a limited use as an antisyphilitic and sedative. It is somewhat astringent and is employed in obstinate diarrhea. ARBUTIN, C 12 H 16 7 Arbutin, to which the above drugs owe at least part of their thera- peutic value, is also administered as a pure substance for diuretic pur- poses and as an urinary antiseptic. Arbutin occurs in long, glistening, colorless needles, or as fine white crystalline, odorless powder having a bitter taste. It is soluble in 8 parts of water and 16 parts of alcohol, and somewhat soluble in ethyl acetate; very soluble in hot water and hot alcohol; insoluble in chloroform, ether, carbon disulphide. Its aqueous solution is neutral to litmus paper and is not precipitated by solutions of the metallic salts or by solutions of tannin. Its aqueous solution is colored blue by ferric chloride test solu- tion, and when boiled with ferric chloride the pungent odor of quinone is evolved. By boiling with diluted sulphuric acid or by treatment with emulsin, arbutin is converted into glucose and hydroquinone. When heated to 100° C. arbutin loses its water of hydration. At 195° C. the anhydrous glucoside melts. Arbutin probably is accompanied by methyl arbutin in the plant. When it is hydrolyzed both the hydroquinone and glucose reduce Fehling's solution. Methyl hydroquinone does not reduce Fehling's solution, but it does give a blue color with ferric chloride while methyl arbutin does not. Arbutin in aqueous solution gives a blue color when treated with a solution of 1 gram of sodium phosphomolybdate in 10 mils of concentrated 336 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS sulphuric acid and 20 mils water (Jungmann's reagent), followed by an equal volume of ammonia water. Methyl arbutin does not react with this reagent, but methyl hydroquinone does. When arbutin is submitted to the action of emulsin, the liquid after the second day becomes pink and gradually darker until it is yellowish- brown. Under the same conditions a solution of methyl arbutin, if pure, will remain colorless for a long time. If arbutin is treated in alcoholic solution with potassium hydroxide, a precipitate of the alkali with arbutin is obtained. The pure glucoside may be separated from this compound by filtering, washing with strong alcohol, boiling with glacial acetic acid under a reflux, neutralizing with calcium carbonate, distilling off any alcohol, and shaking out with ethyl acetate, from which on concentrating the arbutin will crystallize. In the general scheme of analysis of medicinal products, arbutin will be left in solution after the mixture has been subjected to extraction with the different immiscible solvents. If the solution is concentrated, acidified with hydrochloric acid, and refluxed, the arbutin will be converted to hydroquinone and glucose, and the former may then be shaken out with ether and identified. SALICIN AND BENZOYLSALICIN (POPULIN) Salicin occurs in the bark of the white and black willow, Salix alba and S. nigra (Salicacese) and populin in the bark of some of the genus Populus, three representatives of which are used medicinally. Salix fragilis, crack willow, furnishes considerable of the salicin of commerce. Salix alba is the European or white willow, a large tree, native of Europe, and introduced into this country. Its bark is used as a tonic, febrifuge, astringent, and antirheumatic, but has been largely superseded by its glucoside, salicin, which is now prepared in the pure condition and has the honor of being the only glucoside recognized in the U. S. Pharmacopoeia. Salix nigra, the black or swamp-willow, is native in this country and its bark possesses similar properties to that of S. alba. Its buds are also used medicinally and are claimed to exert a peculiar sedative influence on the sexual organs. The barks of Populus alba, white or silver-leaf poplar, and P. tremu- loides, quaking aspen, possess tonic, diuretic, and febrifugal properties. P. candicans, Balm of Gilead, is a large tree, the leaf buds and barks of which are used medicinally. Salicin is marketed alone in the form of pills and tablets of different strengths from 1 to 5 grains. It is also combined in various mixtures with zinc oxide, belladonna, hydrastin, and pepsin; and with caffein, acetphene- tidin, and ammonium salicylate. GLUCOSIDES 337 Salicin, C13H18O7, occurs as a crystalline silky powder or white, shin- ing, tabular crystals or scales, melting 198-201°. It dissolves readily in hot water and hot alcohol, less readily in the cold, and is insoluble in the ordinary organic solvents. It is ortho-hydroxy benzyl glucoside, CeH^OCeHnC^CH^OH, and on hydrolysis by emulsion yields one molecule of saligenin (o-hydroxybenzyl alcohol) and one of glucose. Salicin is not precipitated by lead acetate, basic lead acetate, tannin, or alkaloidal reagents. Its solution can therefore be clarified by lead, filtered, the lead removed by hydrogen sulphide, the solution neutralized and concentrated, and the glucoside recovered in part by crystallization provided it is present in fair amount. The pure glucoside is neutral in reaction, laevorotatory (a) D — 65° in aqueous solution. With concentrated sulphuric acid it gives a bright- red color which is destroyed by water with the deposition of a deep-red powder. When warmed with bichromate and sulphuric acid and then treated with water the odor of salicylic aldehyde is evolved. Froehde's reagent gives a purple color. Its aqueous solution is not colored by ferric chloride. When boiled with dilute mineral acids salicin is hydrolyzed to dextrose and saliretin, the latter separating as a white substance, removable from acid solution by ether and capable of being converted to picric acid by nitric acid. If the hydrolysis is performed with emulsin at a temperature of 37° C, saligenin and dextrose are produced, and the former may be removed by shaking out with ether. It gives an indigo-blue color with ferric chloride and its other properties are fully described on page 553. In the general scheme of analysis salicin will be left in the aqueous solu- tion after the extraction with immiscible solvents, and its presence may be detected by the hydrolyzing of the solution with emulsin or by crystal- lizing as described above. To estimate salicin in pills or tablets, a solution of the sample should be hydrolyzed by emulsin at 37° C. and the saligenin removed by ether, collected in a tared dish, the solvent evaporated and the residue weighed. If sugars are not present the dextrose could be determined and the salicin calculated, but most medicines usually contain some reducing sugar, which will of course vitiate any results obtained in this way. SALINIGRIN, Ci 3 Hi 6 7 Salinigrin is reported by Jowett : as occurring in the bark of certain species of willow. It yields m-hydroxybenzaldehyde and glucose on hydrolysis. It melts at 195°, is fairly soluble in cold water, and very soluble on warming, sparingly soluble in cold alcohol, but more so in hot 1 Trans. Chem. Soc, 1900, 707. 338 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS alcohol, sparingly soluble in hot acetone, almost insoluble in ether, petroleum ether, and chloroform. It gives no color reaction with sul- phuric acid. It is lsevorotatory (a:)z>i6= — 87.3°. POPULIN, C2oH 22 8 Populin or benzoylsalicin crystallizes with two molecules of water, which it loses at 100° C. The anhydrous substance melts 180°. It has a sweet taste, resembling that of licorice. It is slightly soluble in cold water and fairly soluble on boiling, slightly in alcohol and insoluble in ether. Sulphuric acid produces an amethyst-red color. When boiled with barium hydroxide solution populin is converted to salicin and benzoic acid. Dilute mineral acids produce dextrose, benzoic acid, and saliretin. It is unacted upon by emulsin. GLUCOSIDES OF THE BLACK HELLEBORE AND ALLIED DRUGS OF THE RANUNCULACEJE The rhizome of Helleborus niger (Ranunculaceae) , black hellebore or Christmas rose, is used principally in female pills and emmenagogues. It was formerly used for dropsy and epilepsy, and Bacher's pills for the former disorder were reputed to consist largely of this drug. The types of female and emmenagogue pills containing black helle- bore include in addition ergot or some proprietary preparation of ergot, aloes, ferrous sulphate, and oil or extract of savine; aloes, ferrous sulphate, Jamaica ginger, myrrh, soap, and Canella alba (cinnamon or whitewood bark), which represents the Hooper formula; cotton-root bark, ergot, ferrous sulphate, aloes, and savine oil. The drug contains helleborin, C36H42O6, a glucoside, forming white glistening needles, soluble in alcohol and ether, but insoluble in water. It is tasteless in the isolated condition, but in alcoholic solution it produces a burning, numbing sensation on the tongue. Concentrated sulphuric acid dissolves helleborin with an intense red coloration which gradually disappears and a white precipitate separates. It yields glucose and helle- boresin on hydrolysis. Helleborein, C26H44O15, is found in the seeds and leaves of H. niger, but apparently is not present in the root. It forms fine, hygroscopic needles which are bitter and cause sneezing. It is soluble in water and alcohol, but not in ether, and hence can be easily separated from helle- borin. With concentrated sulphuric acid a golden-yellow to reddish- brown coloration is obtained. It yields dextrose and helleboretin on hydrol- ysis, the latter being a violet blue substance when moist. Helleborein may be precipitated from aqueous solution by tannin, but not by basic lead acetate. GLUCOSIDES 339 Glucosides of Adonis vernalis Adonis vernalis (Ranunculaceae), false hellebore or bird's eye, is a European and Asiatic species, the whole plant furnishing a drug having diuretic and heart-tonic properties. It is used for these purposes and also as a substitute for Helleborus niger. It contains helleborein, adonidin, and picradonidin, all glucosides, and adonidic acid. Adonidin has been separated in a state of partial purity and appears to be an intensely bitter, odorless, hygroscopic substance, readily soluble in water and alcohol, but insoluble in chloroform and ether. It is not precipitated by either neutral or basic lead acetate, but is thrown out by tannin and is therefore readily separated from the adonidic acid which gives an insoluble compound with lead. When adonidin tannate is treated with zinc hydroxide and alcohol, evaporated to dryness at 40- 50°, and extracted with absolute alcohol, the adonidin goes into solution. Adonidin in its action closely resembles certain of the digitalis gluco- sides. Adonis aestivalis, a closely allied plant of the same general habitat, probably contains adonidin. The drug is used as a remedy for obesity. Actea spicata The rhizome and rootlets of Actea spicata possess properties similar to Hellebore and are sometimes substituted for it. The plant is a native of Europe and Asia and is known as the baneberry or white cohosh. In the United States we have two species of Actea having a limited use as drugs, A. alba and A. rubra. They are closely related to A. spicata, which is the type species and are known respectively as white cohosh or white baneberry and red cohosh, red baneberry or black cohosh (this term is misleading, as the true black cohosh is Cimicifuga racemosa). The rhizomes of all these plants are violent purgatives, and according to Kraemer the European species contain helleborein. Cimicifuga racemosa. Black Cohosh The plant furnishing the drug so well known in this country as black cohosh or Macrotys is closely allied to the Acteae, and the growing plant unless in blossom is readily mistaken for A. alba. Its reputation is depend- ent on its properties of relieving headache and uterine pains accompany- ing pregnancy, and in re-establishing the menstrual flow. It will con- sequently be found in remedies for female troubles. To a lesser extent black cohosh is used as a tonic, nervine, antispasmodic, and antirheumatic. As an antispasmodic it is employed in St. Vitus dance. It is dispensed alone and in combination in pills and tablets with wild cherry, ipecac, and licorice ; with morphin and quinin in dysmenorrhea mixtures ; with aloes, 340 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS cotton root bark, and ferrous sulphate; with Podophyllum resin, leptandra, juglans, and Capsicum; with aconite, belladonna, and colchicin; with lithium, salicylates, Phytolacca, and colchicin. In liquid mixtures it accompanies salicylic acid, potassium iodide, and Gelsemium. It is the essential ingredient of the so-called "Mothers' Cordials" or " Parturient Balms," and may be accompanied by aconite or Veratrum viride. The root was used by the Indians as a remedy for snake bites, and the plant is also called black snakeroot. The roots of C. Americana and C. cordifolia are undoubtedly often substituted for C. racemosa. The three plants grow in the Eastern floral section of the United States and the close resemblance of Americana to the common drug would be confusing to anyone but a trained drug col- lector or botanist. The chemistry of the black cohosh rhizome is as yet unreported. It contains a resin, which is probably of complex composition. This resin is known as macrotin or cimicifugin and will be found listed in the drug catalogues under the head of "concentrations." It imparts a sweet taste to water, and upon prolonged chewing the taste becomes disagreeable and the throat experiences a burning or smarting sesnation. Tannin- like substances giving a black color with ferric chloride are present. Extracts of fresh root are employed in eclectic practice. They have a sweet taste and a golden-yellow color. CYANOGENETIC GLUCOSIDES, OIL OF BITTER ALMONDS AND HYDRO- GEN CYANIDE Wild Cherry Bark and 1-mandelonitrile Glucoside Padus virginiana, syn. Prunus serotina (Amygdalacese) the wild black cherry, a large indigenous tree most abundant in the Southwestern States, furnishes the drug Prunus virginiana or wild-cherry bark. The tree some- times attains a height of 90 feet with a maximum trunk diameter of 4 feet and is straight, the trunk being covered with a rough black bark, the young branches smooth and reddish. It is readily distinguished from Padus nana, the common choke cherry, a shrub growing from 2 to 10 feet, and from P. melanocarpa, the Rocky Mountain wild cherry, a smaller tree. The bark is official in the U. S. Pharmacopoeia and is collected in the autumn. The outside layer is first removed, so that the green layer under- neath shows. The best grade is known as "thin green," the next grade "thick green," and the low grade "thick rossed." Wild cherry bark is commonly employed as an ingredient of remedies intended for coughs and pulmonary complaints. It will be found in liquid White Pine compounds combined with white pine bark, balsam poplar buds, spikenard, Sanguinaria, Sassafras, morphin, and chloroform; in GLUCOSIDES 341 sedative cough mixtures with codein, Cannabis sativa, white pine bark, Eriodictyon, balsam poplar buds, chloroform, and glycerin; with Erio- dictyon, licorice, salicylic acid, Grindelia, pine tar and potassium bromide; with Sanguinaria, Marrubium, comfrey, spikenard, Inula, and Ceanothus americanus (Jersey tea). Alcoholic extracts of Wild cherry bark intended for the preparation of syrups and other purposes, often contain other drugs such as Marrubium (Horehound), Veratrum viride, Sanguinaria, and wild lettuce; or Cimicifuga, ipecac, licorice, and senega. Elixirs intended as tonics and stimulants to the digestive tract will be found containing wild cherry, Taraxacum, and licorice; and gentian, Taraxacum, Eucalyptus, licorice, and Eriodictyon The tablet and lozenge combinations are of the same general type as the liquids, thus we often meet with wild cherry combined with white pine bark, squill, senega, ipecac, Sanguinaria, opium, camphor, potassium nitrate, and methyl salicylate; with terpin hydrate, guaiac, opium, cam- phor, and belladonna; with licorice, pine tar, Eriodictyon, and senega; with licorice, colts foot, acacia, Marrubium, anise, cubeb. Capsicum, and tolu. One of the most widely advertised preparations of wild cherry is the well-known confection recommended for coughs and colds. These wild cherry drops are sold in enormous auantities and consist almost entirely of sugar. The characteristic glucoside of wild cherry bark is Z-mandelonitrile glucoside, which also occurs in the bark of Cerasus padus syn., Prunus padus and isomeric with sambunigrin and prulauresin, the /3-glucoside of dextro and racemic mandelonitrile respectively. Sambunigrin occurs in the leaves of Sambucus nigra, the common black elder and prulauresin in the leaves of the cherry-laurel, Prunus lauro-cerasus. An aqueous decoction of the bark yields hydrogen cyanide and con- tains the cyanogenetic glucoside. An alcoholic extract of the bark has been carefully examined by Power and Moore. 1 The portion of the alcoholic extract which was soluble in cold water contained the glucoside, sugar, tannin, benzoic, trimethyl gallic, and p-coumaric acids, and after heating with dilute sulphuric acid, £-man- delic acid and jS-methylsesculetin. The alcoholic extract insoluble in cold water consisted of two resinous substances, one a greenish body insoluble in warm water and the other a brown amorphous product soluble in hot water and depositing slowly on standing. The green resin, amounting to about 1 per cent of the weight of the bark, yielded a phytosterol, C27H46O, melting 135-136°, (a) D — 34.0°; palmitic, stearic, oleic, linolic acids, and apparently a very little isolinolenic acid, ipuranol; and after acid hydrolysis oleic acid, dextrose, and /3-methylaBsculetin, CioHgO^ melting 204°! The 1 Trans. Chem. Soc, 1909, 243. 342 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS brown resin, amounting to about 1 per cent of the weight of the bark, jdelded after acid hydrolysis, a trace of a phytosterol, small amounts of oleic acid, /3-methyla3Sculetin, dextrose, insoluble red resinous material, which on fusion with potassium hydroxide gave formic, acetic, butyric, and proto-catechuic acids. An alcoholic extract of the bark, when distilled with steam, yielded small amounts of benzoic acid and an essential oil, but no hydrocyanic acid. The bark contains an enzyme which hydrolyzes ,3-glucosides. The separation of the Z-mandelonitrile glucoside in a condition of purity is attended with some difficulty and the following method was adopted by Power and Moore in recovering it from the drug: One kilogram of the original alcoholic extract, representing about 3.8 kilograms of the bark, was mixed with 2 liters of water, and the volatile constituents were removed by distillation with steam. The contents of the distillation flask were then filtered while hot from the previously described green resin, the latter being thoroughly washed with water, and the washings added to the filtrate. After allowing the combined aqueous filtrate and washings to stand for several weeks, a quantity of the pre- viously described brown resin was deposited, from which the clear liquid was decanted. This liquid, being large in amount, was divided into four portions, each of which was concentrated as far as possible under dimin- ished pressure. To each portion 200 mils of alcohol were then added, and, after complete solution, the thin syrups were again concentrated under diminished pressure, this operation being repeated until the mass became too viscid for further concentration. Each portion was then dis- solved in 200 mils of absolute alcohol, and to the thin syrups so obtained 1 liter of boiling, dry ethyl acetate was added in each case. After stand- ing for several hours, the liquids were decanted from the precipitated syrup, concentrated to about 100 mils, and while still hot, 500 mils of boiling, dry ethylacetate added to each portion. They were again allowed to stand for several hours, when some syrupy material was deposited, from which the clear ethyl acetate liquids were decanted. These were then united, concentrated to the measure of 500 mils, and, after cooling, 500 mils of dry ether added. The clear liquid was then separated, the solvent completely removed, and the residue dissolved in about 300 mils of cold water. This aqueous liquid was shaken with small successive portions of ether in order to remove the acids which were known to be present, after which it was treated with a solution of normal lead acetate until no further precipitate was produced. The yellow precipitate was removed by filtration with the aid of the pump, and the aqueous filtrate concen- trated on the water-bath under diminished pressure to about 30-40 mils. A mixture of 300 mils of alcohol and 300 mils of ethyl acetate was then added, and the whole allowed to stand overnight. The clear liquid, . GLUCOSIDES 343 decanted from a small amount of a yellow precipitate, was concentrated to a small volume, the residual product being then dissolved in water and treated with hydrogen sulphide for the removal of the lead. After filtra- tion, the aqueous liquid was concentrated under diminished pressure to the measure of about 50 mils, when an excess of calcium carbonate was added to neutralize the free acetic acid, and the mass then extracted with alcohol. This alcoholic extract was evaporated to dryness on a water- bath under diminished pressure, and the residue dissolved in ethyl acetate, when, after concentrating the solution to about 20 mils, the glucoside slowly crystallized in small, colorless needles. It was recrystallized from ethyl acetate, when two crops of crystals were obtained. The first frac- tion of crystals, which amounted to 0.6 gram, melted initially at 144- 146°, and, after further crystallization, at 145-147°. The second frac- tion of crystals, which was very small in amount (about 0.1 gram), was somewhat less pure, and melted at 135-140°. Both these fractions, when treated with emulsin, yielded hydrogen cyanide, benzaldehyde, and glu- cose. The first fraction was analyzed, with the following result: 0.1392 gave 0.2904 C0 2 and 0.0750 H 2 0. C = 56.9; H = 6.0. CuHiyOeN requires C = 5o.9 H = 5.8 per cent. 0.3605, dissolved in 20 mils of water, gave in a 2 dcm. tube as- 1°4', whence (a)z>-29.6°. The above described cyanogenetic compound was thus identified as Z-mandelonitrile glucoside. A determination of the specific rotatory power of the small fraction of glucoside melting at 135-140° gave the following result: 0.0956, dissolved in 20 mils of water, gave in a 2-dcm. tube a D — 0°14', whence («)*>- 24.4°. It has the composition C 6 H 5 CH(OH)CNC6Hio05, and when pure melts 147°, (a) D — 26° or —29.6°, hydrolyzing to dextrose and d-man- delonitrile, C6H 5 CH(OH)CN. When treated with emulsin it yields hydro- gen cyanide, benzaldehyde, and glucose. The isolation of jS-methylsesculetin would indicate that the bark con- tained a small quantity of the glucoside methylffisculin. Amygdalin, C20H27O11N, melts 200° and when treated with emulsin yields hydrogen cyanide, benzaldehyde, and two molecules of dextrose. Sambunigrin and prulauresin, isomeric with Z-mandelonitrile gluco- side, melt and have specific rotation respectively 151° (a) D — 76° and 122° (a) D — 52.75°. The former hydrolyses to dextrose and Z-mandelonitrile and the latter to dextrose and d-Z-mandelonitrile. 344 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The detection of wild-cherry bark in medicinal preparations is usually accomplished by setting free and isolating the hydrogen cyanide and by noting the fluorescence of an extract of the sample due to the methyl aesculin. These tests are not conclusive, but at present they take us as far as we can go. It is not possible to isolate the characteristic glucoside from the amount of material which the analyst ordinarily has at his disposal. The hydrogen cyanide can be isolated both qualitatively and quan- titatively by exhausting the sample with hot alcohol, removing the solvent by evaporation over the steam-bath, transferring the residue with 50 mils water to a distilling flask fitted for steam distillation, adding 10 mils of dilute hydrochloric or sulphuric acid and distilling, keeping the water volume fairly constant until the distillate gives no further test for hydro- gen cyanide. To determine the quantity of this substance the dis- tillate should be treated with an excess of sodium bicarbonate and then titrated with iodine to the appearance of a yellow color. Cherry-laurel Water Cherry-laurel water is prepared by aqueous distillation of the fresh leaves of Prunus lauro-cerasus. The finished product is often employed in Europe as a sedative narcotic but has never been used to any extent as a drug in this country. The distillate contains the essential oil of the leaf, benzaldehyde, and hydrogen cyanide, but the two latter gradually establish an equilibrium, and the liquid then contains hydrogen cyanide and benzaldehyde cyanohydrin. HCN+C 6 H 5 CHO < > C 6 H 5 CH(OH) ■ CN The rapidity with which the final condition of equilibrium is attained depends on whether the solution is more or less acid. The product is an unsatisfactory preparation at best and the cyano- genetic substances are variable. If assayed according to the official method for hydrocyanic acid, the determination should be made as soon as the product is distilled, otherwise the results will not show the total quantity of cyanide bodies present. A distillate from bitter almonds, known as bitter almond water, is prepared in the same way as cherry-laurel water and consists of the same or closely related ingredients. It has been largely replaced by benzal- dehyde water. Power and Moore ! examined the leaves of Padus virginiana and found present £-mandelonitrile glucoside, the same substance present in the bark, 1 Trans. Chem. Soc, 1910, 97, 1099. GLUCOSIDES 345 and also an enzyme which hydrolyzes /3-glucosides. It is not unlikely that these or similar substances, possibly the racemic form of the glucosides, are present in the leaves of Prunus lauro-cerasus and give rise to the prod- ucts of hydrolysis found in the distillate. Hydrocyanic Acid, HCN Hydrocyanic acid is used in medicine for alleviating spasmodic con- ditions, nervous coughing, whooping cough, vomiting, colic, angina pec- toris and cholera. Locally it is applied to the unbroken skin to allay itching. It is, of course, used in very weak solutions and the pharmaco- copceial acid is of 2 per cent strength. It is one of the constituents of chlorodyne and other mixtures of this type, being combined with morphin, Cannabis indica, and chloroform. It is of still further interest to the drug chemist as it occurs as benzal- dehyde cyanhydrin in a number of pharmaceutical preparations which are made from vegetable products containing amygdalin, and possibly other glucosides of similar nature. Thus it is a constant component of Cherry-laurel water or Kirschwasser, an anodyne and antispasmodic remedy distilled from the leaves of the cherry laurel (Prunus laurocerasus), and in natural oil of bitter almonds, and in bitter almond water. The pure acid is a clear colorless liquid with an unmistakable odor, boiling 26.5° and solidifying at —15°. It is soluble in water, alcohol, and ether. Its vapor burns in the air with a violet-blue flame, forming carbon dioxide, nitrogen, and water. It is a weak acid and only tempor- arily reddens litmus. It is known practically only in dilute solutions which are very poisonous. Hydrogen peroxide changes it to oxamide. Silver nitrate produces a voluminous precipitate which is insoluble in dilute nitric acid but will dissolve in concentrated acid. Silver cyanide when boiled with hydro- chloric acid reacts and the odor of hydrocyanic acid is apparent. Hydrocyanic acid may be detected in dilute solutions by adding a few drops of potassium nitrite solution followed by a few drops of ferrous sul- phate and enough dilute sulphuric acid to cause the yellow-brown color of the basic ferric salt to become yellow. The liquid is then boiled, cooled, the excess of iron precipitated with ammonia and filtered. A few drops of freshly prepared ammonium sulphide are then added and a violet color will appear, changing through blue and green to a yellow color. An alkaline solution of hydrocyanic acid or a cyanide on treatment with ferrous sulphate and hydrogen peroxide, followed by an excess of hydrochloric acid will give a precipitate of Prussian blue. Hydrocyanic acid can be estimated in dilute solution or in the almond and cherry waters by weighing out a sample, adding a slight excess of 346 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS magnesium oxide and a few drops of potassium chromate and then titrat- ing with silver nitrate until a brownish-red color is obtained. 1 mil N/10 AgN0 3 = . 002702 gm. HCN The cyanides of mercury and potassium are used to some extent medicinally. The former often replaces mercuric chloride as an anti- septic, and the latter is a sedative and anodyne. Hydrogen peroxide is one of the accredited antidotes in cases of cyanide poisoning, hence it should be looked for in any mixture advertised for this purpose. Oil of Bitter Almond Oil of bitter almond is obtained by macerating the kernels of Prunus amygdalus or of Prunus armenicaca (apricot) with water and distilling. The commercial oil contains a small quantity of hydrogen cyanide and cyanogenetic products (benzaldehyde-cyanhydrin). When freshly dis- tilled it is a colorless liquid, but as it ages it becomes yellow. Its use in medicine is limited. It may be expected in nerve sedatives and cough remedies and to allay severe itching. It is also used as a flavoring agent and to conceal the taste of cod liver and castor oils. For all practical purposes the artificial benzaldehyde answers all the requirements of the distilled oil and when pure is much less poisonous. In order to test for hydrogen cyanide 10-15 drops of the oil are shaken with 2-3 drops of a strong solution of sodium hydroxide. Several drops of ferrous sulphate containing some ferric salt or a little hydrogen per- oxide are added and the mixture shaken and acidulated with hydrochloric acid. Upon solution of the iron salts a precipitate of Prussian blue results if hydrogen cyanide is present. Nitrobenzol is sometimes used as an adulterant and may be detected by dissolving the oil in twenty times its volume of alcohol, adding water until turbidity results, and then introducing zinc and sulphuric acid to generate a slow stream of hydrogen. After several hours the solution is filtered, the alcohol evaporated, and the residual solution boiled with a drop of potassium bichromate which will cause the development of a violet color. The presence of non-aldehydic constituents may be detected by shak- ing 5 grams of the sample with 45 grams of saturated sodium bisulphite solution and then adding water and warming, whereupon non-aldehydic substances will rise to the surface. Artificial benzaldehyde is considered an adulterant of this oil and its presence was formerly considered as established if chlorine could be detected. There are many reasons why this is a very doubtful criterion as to the presence of artificial benzaldehyde, and at the present time an GLUCOSIDES 347 analyst should draw no definite conclusions on the subject unless he has more substantial proof of the sophistication. Probably the simplest method of detecting the presence of chlorine products would be to boil the suspected sample under a reflux with alco- holic potash, evaporate the alcohol, take up with water and remove the oily constituents with ether, precipitate the aqueous liquid with silver nitrate in presence of nitric acid, and identify the silver precipitate as the chloride in the presence of cyanide. Free hydrogen cyanide is determined according to the method described under hydrogen cyanide. Applied to the oil, 1 gram of the sample is care- fully weighed into a small Erlenmeyer flask, and 10 mils of a mixture of freshly prepared magnesium hydroxide and several drops of potassium chromate added. The mixture is then titrated with N/10 silver nitrate until the formation of red silver chromate. The total cyanogen etic constituents are determined by saponifying a weighed sample with alcoholic potash, diluting with water, filtering if necessary, and precipitating with silver nitrate in the presence of nitric acid. After the liquid has become clear the silver cyanide is collected on a tared Gooch, washed with water and dried at 100°. The silver pre- cipitate obtained in this way represents all of the hydrogen cyanide, free and combined, and with the figures of both determinations the rela- tive amounts of each are a simple matter of calculation, GLUCOSIDES OF THE MUSTARD SEED Sinalbin, C30H42O15N2S2 • 5H 2 0. Sinigrin, CioHi 6 9 NS 2 K Mustard seed is the ripe seed of Sinapis alba L. (White mustard), (Cruciferse) , Brassica niger L. (Black mustard), Brassica junicea, or the varieties or closely related species of the type of B. nigra and B. junicea. Sinalbin occurs in the white mustard seed and sinigrin in the black. In addition to these glucosides, sinapin, C16H23O5N, an alkaloid, occurs in both varieties of seeds. Another important constituent is an enzyme, myrosin, which readily hydrolyzes the glucosides when the seeds are powdered and digested with water at the ordinary temperature. Black mustard seed deprived of its fixed oil is used in the manufacture of mustard plasters. As a household remedy, commercial ground mus- tard, which is usually prepared from both white and black seeds, is used in poultices, as an emetic and for relieving obstinate hiccough. Sinalbin Sinalbin forms yellowish needles, melting anhydrous at 138-140°, slightly soluble in cold water and alcohol, readily in hot water and insol- 348 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS uble in ether. Its aqueous solution is alkaline, bitter, and gives a yellow color with alkalies. On hydrolysis by myrosin, it yields dextrose, sinalbin, mustard oil (p-hydroxybenzylisothiocyanate), and sinapin hydrogen sulphate. C30H42O15N2S2+H2O = C6H12O6+C7H7O • NCS+C16H24O5N • H2SO4 Sinigrin Sinigrin is potassium myronate. It crystallizes in colorless needles, melting 126-130°, soluble in water, somewhat soluble in warm methyl alcohol, sparingly in cold alcohol, insoluble in ether, chloroform, and acetone. It is converted by myrosin to dextrose, allyl isothiocyanate, and potassium bisulphate. CioHi 6 9 NS2K-f-H 2 = C 6 H 12 06+C3H5NCS+KHS04 Allyl isothiocyanate is commonly known as mustard oil, and is a vola- tile liquid with a pungent odor and taste. The sinalbin mustard oil is not volatile. Sinigrin gives a white precipitate with basic lead acetate in presence of ammonia. Sinapin Sinapin is not known in the free state, as it decomposes into cholin and sinapic acid when solutions containing it are evaporated. It exists as the thiocyanate in the seeds and is one of the products of hydrolysis of sinal- bin. Aqueous solutions of the free base are alkaline and have a yellow color. Sinapin may be separated from the thiocyanate by treating the solu- tion with silver sulphate, separating the silver precipitate, removing the sulphate with barium hydroxide, leaving the free alkaloid. Sinapic acid, C11H12O5, one of its products of decomposition, crystal- lizes from alcohol in prisms, melting 191-192°. The percentage of allyl isocyanate in mustard seed is ascertained by the method described on page 51. Bitter Tonic Drugs GENTIOPICRIN AND THE GENTIAN GLUCOSIDES Gentiopicrin occurs in the root and other parts of the anatomy of several of the Gentianacese. The rhizome and roots of Gentiana lutea furnish the official drug, gentian, which has attained wide popularity as a bitter tonic and which enters into the composition of a variety of for- GLUCOSIDES 349 mulas. The plant grows among the Apennines, the Alps, the Pyrenees, and in other mountainous or elevated regions of Europe. Several of the species are credited with analogous medicinal properties, and their roots are either mixed with the official drug or are used locally for the same pur- poses. G. lutea requires several years to reach maturity, but the root is gathered at any period during the growth of the plant. The rhizome and roots of G. elliotii, syn., Dasystephana parvifolia, indigenous to the southeastern part of this country, were at one time official. Liquid extracts of gentian are usually flavored with bitter orange peel, cardamon, or lemon peel. Of the numerous types of pill and tablet formulas containing extract of gentian may be mentioned those in which it is combined with Podophyllum, colocynth, Hyoscyamus, Cascara sagrada, Juglans, Nux Vomica and Apocynum; with strychnin, ipecac, black pepper, and oil of cloves; with quinidin, cinchonidin, Althea, and hydrochloric acid (Catarrh formula) ; with colocynth, jalap, Podophyllum, leptandra, Hyoscyamus and oil of peppermint (cathartic compound); with cinchonidin, cardamom, pimento, ginger, pepsin, and hydrochloric acid; with aloes, rhubarb, and caraway; with ipecac, opium, mercury, and chalk; with quinin, arsenic, and atropin; with strychnin, ipecac, Capsicum, rhubarb, and sodium bicarbonate; with Nux Vomica, Ignatia, Cinchona, Calumba, German chamomile, phosphorus, and aromatic powder; with quinin, strychnin, arsenous acid, and reduced iron; with quassia; in Warburg's tincture, which is dispensed in the liquid, capsule, pill, and tablet form, where it occurs with rhubarb, angelica seed, Inula, saffron, fennel, zedoary, cubeb, myrrh, white agaric, camphor, quinin, or cinchonin and cinchonidin, with and without aloes. Elixirs of gentian alone and with other well-known bitters such as colocynth and quassia, will often be encountered, as well as more complex mixtures containing Taraxacum, Yerba Santa, licorice, wild cherry, and Eucalyptus; with iron citrochloride or pyrophosphate with or without pepsin. Adulteration with Rumex alpinus has been reported. The root of Fra- sera carolinensis, American calomba or yellow gentian, which grows in the Eastern United States and Canada, resembles in the whole condition the official gentian, but is lighter in color. It contains gentiopicrin. The fresh root contains the glucosides, gentiopicrin, and gentiamarin, and possibly a third known as gentiin, and a carefully prepared dialyzed extract of the fresh root in 60 per cent alcohol contains them in an unaltered condition. As the root is ordinarily dried for the market these glucosides are broken down, due to the action of emulsin, and as they are also hydro- lyzed even in the presence of alcohol, ordinary medicinal preparations contain only their decomposition products. This action seems to impair 350 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS but little the bitter effect of the drug, and the therapeutic significance of the undecomposed glucosides has not yet been determined, though their decomposition is detrimental to the identification of the drug by chemical means. The glucosides are not precipitated by lead subacetate, and they may be separated from the root or a drug extract by extracting with alcohol. If carefully dried under cover, gentian will lose but a small quantity of gentiopicrin, and the marketable drug may then contain from 5-6 per cent, the loss ordinarily sustained is due to fermentation previous to or during drying. Tinctures made by macerating for a long period with 60 per cent alcohol lose practically all the gentiopicrin, but if the powdered root is heated to boiling with 60 per cent alcohol for twenty minutes and then cooled and macerated, the tincture will contain the glucosides. The fresh gentian root contains the glucosides above mentioned, gen- tisin, quercitrin or an allied product, saccharose and possibly other sugars, pectin and other substances not yet studied. Unless carefully dried the saccharose is changed during the process of curing. Gentiopicrin Gentiopicrin crystallizes in two forms, anhydrous, C10H20O9, and hydrated, CioEboOg-f-iBkO; the former, melting 191°, is obtained from absolute alcohol or anhydrous ethyl acetate; the latter, melting 122°, from water or hydrated ethyl acetate, it is dehydrated at 105°. It has a lactone structure and forms gentiopicrinates with alkalies. Hydrated gentiopicrin has (a) d— 198.75. It forms a pentacetyl derivative, melting 139°. It is slightly soluble in ether and is removed from acid solutions to a slight extent by that solvent. On hydrolysis by emulsin or dilute sulphuric acid it yields gentiogenin, which is insoluble in 60 per cent alcohol. Gentiogenin gives a characteristic reaction with concentrated sulphuric acid. If dissolved in 3-4 mils of 95 per cent alcohol and an equal volume of acid added without mixing, a blue zone appears at the point of contact. If dissolved in the acid the solution is brown, and adding water drop by drop the blue color develops. Gentiamarin, Ci 6 H2 Oio or Ci 6 H 2 20io Gentiamarin is amorphous and bitter, (a) D — 80° or —90°, the higher value being due to traces of gentiopicrin. When hydrolyzed with sul- phuric acid it gives an amorphous brown substance which is not gentio- genin, as it does not give a blue color with sulphuric acid. It does not possess a lactone structure nor does it combine with alkalies nor yield an acetyl derivative. GLUCOSIDES 351 Gentiin Gentiin crystallizes from 60 per cent alcohol in pale yellow microscopic needles, melting 274°; slightly soluble in water and gives a blackish-green color with ferric chloride. It has no lactone structure. With nitric acid a green solution is obtained, changing to orange on the addition of alkali. When hydrolyzed in a sealed tube with dilute sulphuric acid, glucose and xylose are formed, together with a yellow, crystalline substance, C14H10O5, melting 225°, and subhming 195°. The identification of extract of gentian root in medicines, unless present in large quantity, is not easy of accomplishment because of the instability of the active principles. The separatioa and identification of gentiopicrin and gentiamarin may be accomplished by following Tanret's procedure which is also a quantitative method for a proximate assay of the root. The details are as follows: An alcoholic extract of the drug or of a medicinal mixture is freed of its alcohol and dissolved in water. It is then extracted several times with ethyl acetate saturated with water, the combined solvents filtered, concentrated, and allowed to stand, when a syrupy deposit will be obtained. This deposit contains the gentiopicrin and gentiamarin with a little gentiin, the greater portion of the latter remaining behind in the ethyl acetate. The syrupy mixture is then dissolved in an equal weight of boiling absolute alcohol, and on cooling impure gentiopicrin will crystallize. By repeated crystallization from ethyl acetate containing 2 per cent water, the more soluble gentiin will be eliminated and pure gentiopicrin obtained. The alcoholic mother liquor from which the impure gentiopicrin first crystallized is evaporated to a syrup, extracted with ether and chloroform, then dissolved in water, and precipitated with a 20 per cent solution of tannin. After filtering, the solution is treated with a large excess of tannin and the glucosidal tannate salted out in the cold with magnesium sul- phate, and then extracted with 80 per cent alcohol. The alcoholic solu- tion is shaken with hydrated lead oxide, filtered, the excess of lead removed and the filtered alcoholic solution concentrated in vacuo, the residue con- sisting of gentiamarin. The gentiin remaining in the ethyl acetate is recovered by evaporating the solvent and crystallizing the glucoside from 60 per cent alcohol. Chirata Swertia chirata (Gentianaceae) is a simple bitter tonic having a limited medicinal use. The entire herb constitutes the drug. Chirata is sometimes combined with iron, Euonymus, Podophyllum resin, Veronica, and creosote. The chemistiy of this drug has been imperfectly determined, but it 352 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS contains one or more bitter principles which are probably related to those occurring in other drugs of the Gentianacese. The presence of ophelic acid, C13H20O10, and chiratin have been reported. The latter is described as a yellow hygroscopic powder, sparingly soluble in cold water, but readily in hot water, alcohol, and ether, with a neutral reaction, and giving a heavy precipitate with tannic acid. On hydrolysis it yields ophelic acid and a bitter substance. Chirata is a native of India, where its medicinal virtues have been held in high repute for a long time. The name has been applied to many other bitter drugs sold in India and some of these false chiratas have reached our markets. Elaterium and Elaterin The juice of the fruit of Ecballium elaterium (Cucurbitaceae) yields a sediment to which the name elaterium has been given. This product, which has powerful purgative properties, contains about 30 per cent of commercial elaterin, which is resolvable into two isomeric principles, a- and /3-elaterin. a-elaterin constitutes from 60-80 per cent of commercial elaterin and is devoid of purgative action, the physiological property of the drug being due to the /3-compound. Elaterin occurs as such in the fresh juice and is not in glucosidic combination. Both elaterium and commercial elaterin are employed as medicinal agents and are dispensed chiefly in the form of pills and tablets of small grainage. On account of their powerful action neither the drug nor its active principle are sold as popular remedies, but are prescribed in the treatment of dropsy. The crude drug varies greatly in its strength, due to amount of elaterin present. It occurs in light, friable, flat, or slightly curved opaque cakes about to in. thick, of a greenish-gray color, becoming yellowish by ex- posure, with a faint tea-like odor, and a bitter, somewhat acrid taste. It is inflammable and so light that it swims when thrown upon water. In- ferior specimens are paler in color without any green tint, soft and friable, and usually sink in water. The best grades come from England, where the plant is cultivated and the elaterium prepared as a regular industry. About 6 per cent of the drug is soluble in water. A small quantity of starch is present in authentic specimens. Alcohol and chloroform extract a dark-green resin. The resin dis- solves freely in ether and may be thus readily separated from the elaterin, which is only sparingly soluble. The elaterin of the pharmacopoeias is a nearly colorless, tasteless, crystalline powder, melting and decomposing at 217-220°, sparingly soluble in ether and alcohol, readily in chloroform, and precipitated from its solution in the latter by the addition of ether. Elaterin is soluble in alkalies and is precipitated by acids. It may MM GLUCOSIDES 353 be removed from acid aqueous mixtures by ether, but more readily by chloroform. Elaterin and elaterin residues give with concentrated sulphuric acid, a pink color, quickly changing to reddish-yellow; with Froehde's reagent a pink to yellowish-green to deep green; with ammonium vanadate in sulphuric acid, an intense blue, soon fading to dirty yellow, undissolved crystals becoming orange and finally deep green, which is a very character- istic reaction. Power and Moore x by fractionally crystallizing commercial elaterin from absolute alcohol, have separated two isomeric substances to which they give the names a- and /3-elaterin. r"~ a-elaterin, C28H3SO7, forms hexagonal prisms, melting 230° C, very sparingly soluble in absolute alcohol, (a) D — 52.9° in chloroform. The molecule contains an acetyl, a lactone, and two phenolic groups. When oxidized with chromic acid it yields a ketone elaterone, C24H30O5, crys- tallizing from alcohol in needles, melting 300°, (a) D + 120.5° in chloro- form. /3-elaterin has apparently the same empirical composition and crys- tallizes in plates which are readily soluble in absolute alcohol. It melts 190-195°, (a)z>+13.9°. It is to this body that the purgative value of elaterin and the drug is due. Power and Moore conclude that the only means of arriving at the physiological value of the drug would be to adopt definite limits for its specific optical rotation. The dosage of a product conforming to such a standard could then be adjusted in accordance with the results obtained by physiological or chemical tests. Colocynth The pulp of the dried, peeled fruit of Citrullus colocynthus (Cucur- bitacese) is the official drug colocynth. It is a powerful hepatic stimulant and hydragogue cathartic and has an extended use in medicine, being usually combined with other cathartics and dispensed in the form of pills and tablets. The well-known colocynth comp. pills consist of colocynth, aloes, scammony, and oil of cloves, and when made according to the British formula contain potassium sulphate in addition. The U. S. P. vegetable cathartic pills consist of colocynth comp., Hyoscyamus, jalap, leptandra, Podophyllum, and oil of peppermint. Colocynth comp. is present in several types of mixtures with Hyoscyamus, e.g., with Hyos- cyamus and mercury mass, with podophyllum, with calomel and gentian, with rhubarb and oil caraway, with aloes and tartar emetic, with Nux Vomica, with jalap, Podophyllum and capsicum; with calomel and Podo- 1 Pharm. J., 1909. 354 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS phyllum; and with calomel and Colchicum. Formulas similar to the U. S. P. cathartic compound also may contain gentian, gamboge, soap, cardamon, ginger, rhubarb, leptandra, and ipecac. Colocynth compound occurs with Cinchona alkaloids, oleoresin pepper and ferrous sulphate; strychnin, belladonna, ipecac, and mercury mass; rhubarb, aloes and mercury mass; with calomel; with mercury mass alone, and with ipecac; with Podophyllum; with Podophyllum and calomel; with Podophyllum, calomel, belladonna, ipecac, Nux Vomica, and oil of anise; with Podo- phyllum, aloin, Nux Vomica, Capsicum, and croton oil; with inspissated ox gall, pancreatin, quinin, Nux Vomica, and Taraxacum; with quinin. Colchicum, Hyoscyamus, opium, and mercury mass. Powdered colocynth or its extract is combined with aloes, gamboge, soap, and anise; with Podophyllum, Hyoscyamus, Cascara sagrada, jug- lans, Nux vomica, gentian, and Apocynum cannabinum, and in other formulas of the same general character as those above described, but in most products colocynth is added as the extract of colocynth comp., and if the formula is given, the grainage is usually expressed in terms of the latter compound and not as colocynth extract alone. The presence of seeds in the powdered drug is indicated by the appear- ance of numerous albuminous granules derived from the cotyledons. If the powder is placed on a glass slide, with a drop of water and a cover glass rubbed over it, fragments of the double-walled embryo sac show on the outer side elongated, more or less hexagonal, thin-walled cells, and on the inner side irregular, tabular, thick-walled cells. An amount of fixed oil in excess of 2 per cent, determined by petroleum ether extraction is further indication of the presence of seeds. The ash of colocynth pulp may run from 7.2-13.5 per cent. Power and Moore x found that the active principles of colocynth are a weak alkaloid and a non-basic indeterminate substance in the resin. The alkaloid has an extremely bitter taste, is soluble in water and dilute acids and precipitated by the ordinary alkaloidal reagents, tannin and basic lead acetate. It is soluble in chloroform, but not to any extent in ether. It is removed from its chloroformic solution by hydrochloric acid. The resin is only partly soluble in alcohol, the insoluble portion contain- ing a-elaterin, melting 232°, sparingly soluble in ether, and less so in alcohol and water, but readily in chloroform. The alcoholic soluble portions contain non-glucosidic substances of a purgative nature. Power and Moore also isolated from the pulp a new phytosterol gluco- side to which the name citrullol was given. This substance is soluble in water, from which it may be removed by repeated extraction with ether. On crystallization from pyridin it melts 285-290°. When dissolved in chloroform with a little acetic anhydride, the addition of concentrated 1 Trans. Chem. Soc, 1910, 99. GLUCOSIDES 355 sulphuric acid will produce a series of color reactions similar to those given by the phytosterols. This same substance has been isolated from the drug Euonymus atropurpureus. The seeds contain a trace of the same alkaloid but no a-elaterin. No evidence could be obtained of the presence in colocynth of /3-elaterin, which constitutes the physiologically active constituent of the fruit of Ecballium elaterium. As a result of this investigation it would appear that the so-called " colocynthin " of previous investigators is a mixture of citrullol and the alkaloidal principle. ■When manipulating colocynth extracts in solution according to the scheme of analysis for obtaining qualitative reactions, an extract will be obtained by shaking out the acid solution with ether, which will give a yellow -brown color with concentrated sulphuric acid, a dirty-red to cherry- red with Froehde's reagent, and a red, also pink to deep crimson with ammonium vanadate and the first color obtained in the last test will show blue in thin layers. The basic or alkaloidal constituent of colocynth is of little value as an aid in detecting colocynth in mixtures on account of the small quantity occurring in the drug, and because its chemical properties are not well defined. If a sufficient quantity can be extracted and its purgative action tested on animals, a strong positive indication of the presence of colo- cynth would be established. But as colocynth is dispensed to such a large extent with Hyoscyamus, the mydriatic alkaloids will almost com- pletely mask the colocynth bases. The analyst will be obliged to depend upon the isolation of intensely bitter residues by an ether extraction of an acidulated aqueous extract of the alcohol soluble portion of the medicine under examination, and to diagnose the presence of colocynth by a careful observation of the color reactions performed on these residues. On rendering the acid solu- tion alkaline the alkaloidal constituent is removed by agitation with chloroform. The alcoholic soluble portion of the medicine, after washing with wateT to obtain the above-mentioned solution, will probably be a resinous mass which on careful treatment with absolute alcohol may leave a small por- tion of a-elaterin undissolved, and which on crystallization from absolute ether may be identified by its melting-point. This evidence is not neces- sarily conclusive of the presence of colocynth, because the absence of j8-elaterin should be established, otherwise it may transpire that com- mercial elaterin, or Elaterium, is present in the mixture. That portion of the resin soluble in absolute alcohol will be found to have a purgative action if submitted to a physiological test, but this evidence is of no value in establishing the presence of colocynth in mix- 356 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS tures, because the purgative principles of scammony and some of the other cathartic drugs which usually accompany colocynth reside in resins which will appear at this point and are soluble to a greater or lesser extent in alcohol. Colocynth extracts are not precipitated by iron salts, neither do they give any color reactions with the same reagent because no tannins are pres- ent, and the drug is one of a very few that does not contain some tannin- reacting substance. Quassia The wood of Picrsena excelsa (Simarubese) contains a bitter substance or group of substances to which the name quassia is given. The drug is a bitter tonic and is employed in cases of impaired digestion to tone up the stomach, and is usually combined with iron, Nux Vomica, magnesium sulphate, or gentian. The wood is sometimes turned into cups which can be rilled with water and the liquid imbibed for its bitter and tonic action. Strips of porous paper saturated with quassia syrup are used for fly poisons. The drug appears to have been obtained from two plants of the same genus, the original quassia coming from Quassia amara (Picrsena amara), a small branching tree or shrub of Surinam, West Indies, northern South America, and some tropical parts of the Old World. The P. excelsa, which supplies the present commercial drug, is a large forest tree native of Jamaica and the Caribbean Islands. Quassia occurs in cylindrical billets of various sizes and lengths, fre- quently accompanied with a light-colored sweetish, slightly adherent and bitter bark. Again it will be found in splinters or chips. Quassin is apparently a composite substance, analogous in this respect to commercial elaterin. It crystallizes in oblique rhomboidal needles with a pearly luster. It is odorless, but has a bitter taste. Its melting-point is 210° C. and on cooling it forms an amorphous mass. It is soluble in about 400 parts of water at 15° C; in 30 parts alcohol (85 per cent) and in 21 parts of cold chloroform. It is very soluble in boiling alcohol, in acetic acid, and very slightly soluble in ethyl and petroleum ethers. It is soluble in concentrated acids and alkalies, but not in alkaline carbonates. Continued action of alkalies forms resins. It is dextrorotatory in its chloroform solution; 4.22 gm. in 100 mils chloroform rotating the plane of polarized light to the right with a specific rotation of plus 38° 8'. Solu- tions of quassin are neutral. It dissolves to a colorless solution in concentrated sulphuric acid, which becomes red on the addition of sugar. It is precipitated by tannin from aqueous solution, but not by neutral or basic lead acetate, iodine, iron, or potassium mercuric iodide. GLUCOSIDES 357 Quassin may be removed from an aqueous acid solution by chloroform and the residue left on evaporating the solvent subjected to the color test with sulphuric acid and sugar. Concentrated sulphuric acid alone produces no color. Allen has suggested a reaction with bromin water, which is of value in identifying quassin and in detecting it in presence of other bitters. The residue is dissolved in chloroform and shaken with an excess of bromin water, the chloroform solution separated and shaken with ammonia. The color due to bromin will immediately disappear and if quassin be absent both the solvent and ammonia will be colorless, but in presence of quassin the chloroform will be colored bright j T ellow. Quassin has been separated into two components, a- and /3-picrasmin. The alcoholic extract is neutralized with magnesia, then acidified with tartaric acid, and the alcohol distilled off. The residue is shaken up with chloroform and the solution evaporated to syrupy consistency and dis- solved in a mixture of equal parts of absolute alcohol and ether. This solution is evaporated and the residue dissolved in as little absolute alcohol as possible, the solution covered with a layer of ether and allowed to evaporate. The crystals which form are recrystallized from alcohol. The product thus prepared consists of two bitter principles, a-picrasmin (C35H48O10), melting at 204° C, and /3-picrasmin (C36H48O10), melting at 209-212° C. Simaruba Bark The bark of the root of Simaruba officinalis was formerly recognized in the Pharmacopoeia. The plant is a large tree closely allied to the quassia, and the drug contains a bitter principle which may be related to quassin. The bark contains a fixed oil, resinous material, a crystal- line bitter substance, a crystalline non-bitter substance, gallic acid and a fluorescent principle. The tree grows well in Jamaica. S. amara is indigenous to Brazil and Guiana and S. glauca to the West Indies and Central America. Simaruba has a limited use as a bitter tonic and in solution might readily be mistaken for quassia except that it contains gallic acid, which gives a precipitate with iron salts. However, this difference is of little importance analytically as the bark of quassia may be admixed with the wood of the official drug and it is not unlikely that gallic or tannic acid would be present in the bark. Juglans. Butternut root-bark The root-bark of Juglans cineraria (Juglandacese) has a mild cathartic and tonic action and is often present in mixtures intended to relieve con- stipation and biliousness. As a general thing it is mixed with Podo- 358 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS phyllum resin, colocynth, Hyoscyamus, Cascara sagrada, Nux Vomica, gentian, Apocynum, senna, and Rochelle salt in some combination or other, and certain special types of preparations contain the extract of butternut with manganese iodide, Sanguinaria, Hyoscyamus, and Veronica virginica; and with Podophyllum resin, Cimicifuga, Veronica virginica, and Capsicum. A concentrated extract of the drug consisting chiefly of the resinous constituents is marketed as juglandin. Coto Coto and Para coto barks are closely allied drugs of uncertain botan- ical origin from Bolivia and Brazil. Coto and its characteristic principle, cotoin, are used in diarrheic conditions, for cholera and rheumatism and as stomach tonics. Cotoin, C6H 2 (OH)2(OCH3)COC6H5, crystallizes in pale yellow lami- nated crystals, but it is usually marketed as a crystalline powder. It has a pungent taste, melts 130-131°, is sparingly soluble in cold water, more readily in hot water, very soluble in alcohol, chloroform, benzol, ether, acetone, and carbon bisulphide, but insoluble in petroleum ether. It is removed from its acid solution by ether. Cotoin crystals, when treated with concentrated sulphuric acid, turn orange, and the solution becomes bright yellow. Concentrated nitric acid produces an immediate blue color, soon changing to black and finally orange brown, with considerable chemical action. This is a very character- istic test. An aqueous solution of cotoin is colored violet brown by ferric chloride. Para Coto Para coto is used like coto as an appetizer and for diarrhea, dysentery, and similar disorders. The chief constituent of Para coto is paracotoin, an indifferent crys- talline, bitter principle, hydrocotoin, methyl hydrocotoin, protocotoin, methyl protocotoin (oxyleucotoin), phenyl coumarin, piperonylic acid, volatile oil, resin, and tannin. Para coto is distinguished from coto by the action of nitric acid on the ether extractive matter. In the case of Para coto the result is the formation of a yellow color and in the case of coto a red color appears. Paracotoin, Ci 2 H 8 4 Para coto is extracted with ether and the ether extract distilled. The residue is fractionated by repeated crystallizations from hot alcohol. The first body to separate out is paracotoin. GLUCOSIDES 359 Paracotoin is a pale yellow, crystalline body, neutral in reaction, tasteless and odorless, melting at 149-152° C. It is difficultly soluble in water, but easily in ether, chloroform, and boiling alcohol. Concen- trated sulphuric and nitric acids dissolve it, forming a yellowish-brown solution. On boiling with a solution of caustic alkalies, a colorless crys- alline body, melting at 82-83° C. and having the odor of coumarin is formed; this body is acetopiperon (para-cumarhydrin) , C9H8O3 or C6H3O2CH2 • CO • CH3, and paracotoic acid, C12H10O5, a yellow amor- phous mass melting at 108° C. Paracotoin fused with potassium hydroxide yields principally piperonylic acid, CsHeO^ One gram of paracotoin shaken up with 10 mils of fuming hydro- bromic acid forms a semi-solid mass of yellow crystals, which on drying over potassium hydroxide lose hydrobromic acid. This residue decom- poses with water and when recrystallized forms paracotoin, recognized by its crystalline form and melting-point. By gradually adding about 1 gm. paracotoin to about 10 mils con- centrated nitric acid, a red-brown solution will result, which, when heated for a short time on the water-bath and cooled, deposits a yellow crys- talline mass. This product recrystallized from acetone and then from benzene or glacial acetic acid, forms golden-yellow crystals, melting at 195° C. This body is dinitro paracotoin, probably of the formula C 12 H 6 (N0 2 )204. An excess of bromin added to a 10 per cent solution of paracotoin in choloroform cooled to 0° C. produces a deep yellow precipitate, which loses hydrobromic acid, and when recrystallized from alcohol forms the mono-bromide of paracotoin (C^HjBrO^, melting at 200-201° C. Fortoin is methylene dicotoin or cotoin formaldehyde. CHAPTER XI PURGATIVE DRUGS THE ANTHRAQUINONE DRUGS There are several well-known drugs which are conveniently con- sidered together because they all contain derivatives of anthraquinone and because their physiological properties are more or less alike. They are aloes, senna, Cascara sagrada, buckthorn, rhubarb, and chrysarobin. Aloes also contains certain well-defined principles known as aloins. The individual drugs, their properties and components will be discussed sepa- rately and a general discourse on their recognition in mixtures will follow. ALOES Aloes is a resinous exudation from the wounds of different species of the genus Aloe (family Liliacese). Commercially there are two important varieties, the Barbadoes and Socatrine, with others of lesser moment. The former, also known as Curacao aloes, is derived from A. chinensis and A. vera, and probably other species, and the latter, which is some- times termed Zanzibar aloes, comes from A. Perryi. Natal aloes, from an unknown source, has almost disappeared from commerce. Cape and Uganda aloes from Cape Colony are derived from A. ferox. Hepatic aloes was the name originally applied to an East Indian aloes of a reddish- brown or liver color, but it is now used to designate certain sorts of dark opaque liver-colored Socatrine aloes. In medicinal products both aloes and aloin are extensively employed, the mixtures containing them being chiefly purgatives, tonic laxatives, emmenagogues, restoratives, and laxative cold mixtures. They are usually dispensed in the form of pills and tablets. The standard liquid preparations, fluid aloes, contain licorice and sometimes myrrh; and the compound liquid aloes contains in addition to these, saffron, cardamom comp., and potassium carbonate. Aloes is also present in the liquid benzoin compounds with benzoin, storax, and tolu. In pill and tablet mixtures aloes will be found combined with soap; soap and asafetida, sometimes with confection of rose leaves; ferrous sulphate or Blaud's mixture with or without Nux Vomica; rose leaves and 360 PURGATIVE DRUGS 361 mastic; sometimes with rhubarb (dinner pills), aromatic powder, and myrrh; belladonna and Nux Vomica and ipecac; iron, arsenous acid, and strychnin; Hyoscyamus, colocynth, and tartar emetic; rhubarb, ipecac, and Nux Vomica; Podophyllum resin; Capsicum and Nux Vomica; mercury mass, rhubarb, and colocynth; gamboge, Podophyllum, Cap- sicum, and croton oil; colocynth, Podophyllum, soap, scammony resin, and cardamom (vegetable cathartic); colocynth, scammony resin, potas- sium sulphate, and clove oil; ergot extract, savin oil, black hellebore, and ferrous sulphate, somet'mes with cotton-root bark, saffron, turpen- tine or pennyroyal oil in emmenagogue mixtures; cimicifuga racemosa, ferrous sulphate and cotton-root bark; gentian, rhubarb, and caraway; mercurous iodide, Podophyllum resin, Hyoscyamus and Nux Vomica; inspissated ox gall, stramonium, and berberin; ox gall, pepsin, ferrous sulphate, and Nux Vomica; sometimes with quinin; rhubarb, myrrh, and peppermint oil, sometimes with soap; quinin, calomel, Capsicum, aconite, ipecac, and opium; and others of similar composition. Aloin will be found in mixtures of the same general type. Some of the standard formulas are composed of aloin, strychnin, and belladonna, to which may be added Cascara sagrada, ipecac, Podophyllum resin, and ginger. Aloes responds to several color reactions and the same reagent often reacts in a different way with the different varieties, thereby furnishing a means of characterizing them. Borntrager's test consists in shaking with benzol an aqueous solu- tion of the drug, or an aqueous solution of an evaporated alcoholic extract, and after separating the benzol solution, agitating with ammonia, when, on standing, a pink color, varying in intensity and shade, will develop. This reaction is also known as the emodin test and is obtainable with all drugs containing anthraquinone derivatives. The pink shade is usually the least intense with aloes and after a little experience, the rapidity with which the color appears and its shade and intensity will enable the analyst to distinguish an aloe reaction from that of other drugs. Klunge's test consists in treating a very dilute aqueous solution of aloes with 1 drop of copper sulphate solution followed by sodium chloride and alcohol. The copper sulphate intensifies the yellow color and the salt and alcohol produce a red tint. Barbadoes and Curacoa aloes give a deep red, Socatrine gives various shades of red and sometimes no color, Natal aloes, a faint red, and the hepatic varieties usually no color. In Cripp's and Dymond's test a small quantity of the substance is triturated in a porcelain dish with 16 drops of concentrated sulphuric acid, 4 drops of strong nitric acid added and about 25 mils of water. A deep-orange to crimson color will result according to the kind of aloes pres- ent, and this color is intensified by adding ammonia. Barbadoes and Curacoa varieties give crimson colors intensified to deep claret, Natal 362 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS deep crimson to intense brownish red; Socatrine and hepatic pale crim- son or orange to claret. Fluckiger's test, which is apparently characteristic of Natal aloes, is obtained by triturating with concentrated sulphuric acid and exposing to nitric acid vapor, when a deep-blue color will develop. Other varieties will sometimes give a faint blue or bluish-green color. Stacy x reports that a cold aqueous extract of Barbadoes aloes gives a pink coloration with potassium ferrocyanide. The solutions must be so adjusted that neither is in excess. In most cases the color appears after five to fifteen minutes and more rapidly on boiling. In more con- centrated solutions the color is deep crimson or blood red. The substance giving the reaction is only slightly soluble in petroleum ether, benzol, and chloroform, and insoluble in ether and ethyl acetate. Socatrine and Cape aloes and commercial aloin give a green color, while aqueous extract of Cascara sagrada and rhubarb do not give any reaction. The color yielded by Barbadoes aloes is destroyed by acids and excess of alkalies; small quantities of alkalies intensify the reaction, at the same time modifying it by the introduction of a brown tint. An aqueous solution of borax produces a green fluorescence with aloes which is visible at considerable dilution. In the U. S. P. test 1 gram of the drug is intimately mixed with 10 mils of water. One mil of this solu- tion and 100 mils of water are treated with a 20 per cent borax solution to obtain the reaction. Cascara gives a similar reaction, but only in a fairly concentrated solution. If an aloes residue is acidified and extracted with ether, the ether separated and shaken with the borax reagent, the green fluorescence will develop in the aqueous layer. The appearance of the fluorescence is often retarded, sometimes an hour will elapse before it becomes apparent. Aloes contain as their most characteristic constituents, aloe-emodin and aloin. The resinous material present yields cinnamic acid, aloe- emodin, and sugar upon acid hydrolysis, and p-cumaric and cinnamic acids on alkaline hydrolysis indicating that glucosides are present. Tschirch and Hoffbauer state that Curacao aloes yields only cinnamic acid and Zanzibar aloes only p-cumaric acids, but Tutin and Naunton obtained both acids from the Curasao variety. E. M. Bailey reports the presence of chrysophanic acid. The aloin of Barbadoes aloes probably has the composition C16H18O7 (C21H20O9 or C2oHi 8 9 , Seel and Kelber) (a) D — 8.3° in 90 per cent alcohol, crystallizing in pale yellow prismatic needles, which are intensely bitter and after drying at 100° melt 145-150°, slightly soluble in cold water, but readily on boiling, slightly soluble in ether, chloroform, carbon bisul- phide, benzole, and petroleum ether, and quite easily in alcohol, acetone, 1 Analyst, 1916. 41, 75. PURGATIVE DRUGS 363 and acetic acid. It forms a tribrom-derivative melting 191-192°, which in turn yields a tetra-acetyl derivative melting 135°, from which it is assumed that barbaloin contains three hydroxy 1 groups. Its structural formula has not been determined with certainty. It dissolves in ammonia or alkalies to a deep orange-red solution with fluorescence. On adding ammonia and calcium chloride a precipitate is obtained. Alcoholic solutions of aloin are neutral to litmus. Their aqueous solutions are colored green or greenish-black by ferric chloride and are gradually precipitated by basic lead acetate. When boiled for twenty-four hours with an alcoholic solution of hydro- gen chloride it yields a trihydroxymethylanthraquinone, isomeric with the emodin from rhubarb and senna. Two isomeric barbaloins, the a and /3, have been reported, the former being reddened in the cold by nitric acid, and the latter only on warming and in this particular resembling the nataloin of Natal aloes. Nataloin has thus far yielded no bromo-derivative. It contains a methyl group. It therefore differs from the barbaloins. The commercial aloin is obtained chiefly from the Curacoa and Bar- badoes aloes. ALOE-EMODIN Aloe-emodin is an hydroxymethyldihydroxyanthraquinone, probably represented by the structural formula OH. C y CH 2 OH >c 6 h 2 < yc<&/ i It is closely related to chrysophanic acid which is a dihydroxymethyl- anthraquinone, and to emodin, which is a trihydroxymethylanthraquinone or hydroxy chrysophanic acid. Aloe-emodin crystallizes in orange-red needles melting 216-218° (224° Beal), sublimable, slightly soluble in water, from which it may be removed by immiscible solvents, and dissolving readily in alcohol, ether, benzol, alkalies, and glacial acetic acid. Its solution in alkalies is pink to deep crimson in color, depending on the quantity present. It is much more soluble in water when it is present with other constituents occurring in the drug, than in the separated and purified state. It gives a pink color with concentrated sulphuric acid and a pink to reddish-pink with Froehde's reagent. 364 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Aloe-emodin dyes wool yellow from an acid bath, the color is stripped by ammonia and on acidulating the alkaline solution a second dyeing may be obtained. An alcoholic solution of emodin on evaporation with ferric chloride leaves a yellow residue; phenolphthalein under similar con- ditions leaves a pinkish residue with an odor of phenol, the co'or disappear- ing on cooling or in presence of moisture. Phenolphthalein imparts no color to wool. The presence of aloes in a medicinal preparation is usually apparent by the characteristic odor. If the pill or tablet is extracted with alcohol and the solvent evaporated, the odor of aloes will often pervade the entire room, and the residue will appear as a deep red varnish. This residue can then be submitted to the tests described above. Aloin alone is not detected as readily as the drug, but as the commercial substance often contains aloe-emodin, a weak Borntrager reaction may indicate the presence of aloin. As aloin is not removed to any extent from aqueous solution by immiscible solvents, and as it is not stable in the presence of alkalies it will often pass unnoticed. But if there is reason to suspect its presence a hot aqueous solution of the alcoholic extract should be filtered from any resinous matter, evaporated to dryness, extracted with absolute ether or chloroform to remove easily soluble acids, and then treated with hot alcohol and filtered from any undissolved sugar. On evaporation of the alcohol, the aloin will be left as a yellow residue and can be identified by its intense bitterness, reaction with nitric acid, and by the color reaction of its aqueous solution with ferric chloride, precipitation with bromine, slow precipitation with basic lead acetate after any tannins have been thrown out by neutral lead acetate, and precipitation of its ammoniacal solution by calcium chloride. In performing the iron test, if a trace of the reagent is added at first, a reddish-violet color is obtained, and then on adding a larger quantity the greenish-black color appears. If the bromine water is added drop by drop at half-minute intervals a violet-red color appears at first, and this changes to yellow after an excess has been added with the appear- ance of a yellow precipitate. Nataloin give a blue color with sulphuric acid and vapor of nitric acid. Compounds or so-called derivatives of aloin are sometimes offered for sale with the claim that they possess certain novelties or advantages over the parent drug. The well-known carbonic ether derivative is one of them, and by boiling aloin with a persulphate a powder is obtained which is claimed to have purgative properties. Formaloin is a conden- sation product of formaldehyde and aloin. PURGATIVE DRUGS 365 RHUBARB The well-known drug rhubarb is the rhizome of several species of Rheum (Polygonaceae) . The commercial varieties are known as Chinese, Canton, and Shensi, and are obtained from R. officinale, R. palmatum, R. palmatum tanguticum, and probably others. R. raponticum yields the English or Austrian variety known as rhapontic rhubarb. Rhubarb is a popular remedy and will be found widely distributed in medicinal products. It has cathartic, tonic, and astringent properties, and is principally used in preparations designed to correct bowel and stomach troubles. In liquid form it is often combined with senna and licorice; with potassium carbonate or bicarbonate, cinnamon, Hydrastis, and oil of peppermint; the latter type often containing pancreatin or papain; aperient mixtures will contain magnesium acetate and rhubarb. Among the pill and tablet combinations may be mentioned those in which powdered rhubarb or its extract is associated with Cascara sagrada, Nux Vomica and aloin; ipecac, and aloes; Hyoscyamus, colocynth comp. and caraway; asafetida and iron; mercury mass, aloes, and colocynth comp.; calomel, Hyoscyamus, and colocynth comp.; alap, Jamaica gin- ger, colocynth conp., gamboge, and calomel; Podophyllum, Hyoscyamus, Capsicum, and aloes; calomel, oap, and aloes; mastic and aloes; Ignatia, Cinchona, and Capsicum; gentian, aloes, and caraway oil; me cury mass and sodium bicarbonate; myrrh, aloes, soap, and peppe mint oil; strychnin, ipecac, and capsicum; opiu n, ipecac, and soap; ipecac, sodium bicarbonate, and peppermint oil, sometimes with Cascara; magnesia; opium, Capsicum, camphor, and peppermint oil in Sun cholera mixture. Warburg tincture is composed of rhubarb, angelica seed, Inula, saffron, fennel, gentian, zedoary root, cubeb, myrrh, white agaric, camphor, quinin sulphate, or cinchonin and cinchonidin and aloes. The powdered drug has been found adulterated with turmeric and hematoxylin. For the detection of rhapontic rhubarb; 10 grams of the powdered sample are boiled for half an hour with 50 mils of dilute alcohol, filtered, the filtrate evaporated to 10 mils, and after cooling shaken with 15 mils of ether. After standing for twenty-four hours the ext act from official rhubarb will be clear, while that from the rhapontic variety will have deposited a crystalline sedmient which appears under the microscope to consist of neddle-like prisms. The crystalline precipitate is filtered, washed with water, and dried and on treatment with concentrated sul- phuric acid gives a purple-red color changing to orange. In testing for turmeric 1 gram of the powder is mixed with 1 gram of boric acid, moistened with 10 mils of dilute sulphuric acid and spread out on a porcelain plate. On drying a purple-red color develops if turmeric is present, but pure rhubarb give only a brown or browmsh-red shade. 366 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The chemistry of rhubarb has been the subject of extended research. Tutin and Clewer * separated a small quantity of an essential oil which gives the drug its characteristic odor, and in the aqueous extract cinnamic and gallic acids, rhein, emodin, aloe-emodin, emodin monomethyl ether, chrysophanic acid, and rheinolic acid, a crystalline mixture of glucosides of the above-mentioned anthraquinone derivatives, dextrose, levulose, tannin, and an amorphous non-glucosidic resin which represented the chief purgative constituent. The resin on hydrolysis gave all of the above derivatives, together with a new compound, a trihydr ox yHihvHrnfln- thracene, C14H12O3, melting 256°. The portion of the alcoholic extract of the drug which was insoluble in water, when t eated with various alkalies, yielded a further quantity of the anthraquinone derivatives, several fatty acids, a hydrocarbon melting 64°, a phytosterol (verosterol), glucosides similar to those above mentioned and amorphorous products. The gallic acid present amounted to over 2 per cent, rhein 0.12 per cent, rheinolic acid 0.003 per cent, emodin 0.78 per cent, aloe-emodin 0.16 per cent, emodin mono-methyl ether 0.22 per cent, chrysophanic acid 0.49 per cent, glucosides 2 per cent, and non-glucosidic resin 10.4 per cent. The relationship of the anthraquinone derivatives is apparent from the following structural formulas: H 2 C H 2 Anthracene II c A. Anthraquinone o II 0H \ / c \ >C6H2< >C 6 H4 OH/ \/ il o Alizarine (Dihydroxyanthraquinone) 1 Trans. Chem. Soc, 1911, 99, 94a PURGATIVE DRUGS 367 O II OH. C /CHs >C 6 H 2 < OH/ V Vtffc/ N >C 6 H 3 / O Chrysophanic Acid II OH x C .CH3 >C 6 H< >C 6 H2< oh/ X (/ X OH II o Emodin II OH. /\ y CH 3 >C 6 H 2 < >C 6 H 2 < OH^ x c x x OCH 8 II O Emodin Monomethylether II OH v A /CH 2 OH >C 6 H 2 < >C 6 H 3 / OH/ x c / II O Aloe-emodin II >C 6 H 2 < >C 6 H 3 -COOH OH/ x c / II O Rhein CHRYSOPHANIC ACID This substance crystallizes from ethyl acetate in deep golden-colored spangles melting at 191° C. (198° Beal). In the purified state it is slightly soluble in water and alcohol, but dissolves readily in chloroform, benzol, 368 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS and ether. From an acidulated aqueous extract of a drug it may be completely removed by ether, and 5 per cent caustic alkalies extract it from its ethereal solution, giving rise to a beautiful purple-red liquid. Its diacetyl derivative melts 204°. Commercially, chrysophanic acid is confused with rhein, both sub- stances being considered identical. The same term is also applied to purified or oxidized chrysarobin from Goa powder, a substance deposited in the wood of Andira araroba. In this form it is used an as alterative and antiparasitic, and in ointment form is employed in psoriasis, herpes, and hemorrhoids. If a solution of chrysophanic acid in alkali is heated with a little zinc dust, the red color changes to yellow, due to the formation of a reduction product. Reoxidation takes place readily by dilution with water and the addition of a drop or two of hydrogen peroxide. An alkaline solu- tion of phenolphthalein is reduced by zinc and the color is not restored by peroxide. EMODIN Emodin crystallizes in deep orange needles melting 252°. Its triacetyl derivative melts 192° C. It is soluble in the organic solvents, and is removed from ether or chloroform by alkalies, forming pink solutions. Emodin can be separated from chrysophanic acid by dissolving a mix- ture of the two substances in chloroform and shaking out with sodium carbonate, which will remove the emodin, leaving the chrysophanic acid to be extracted with potassium hydroxide. EMODIN MONOMETHYL ETHER This substance melts 195° and forms a diacetyl derivative melting 186°. It may be converted into emodin by heating to 160° with con- centrated sulphuric acid. Aloe-emodin has already been described under Aloes. RHEIN Rhein is a true acid, and is not readily soluble in the ordinary organic liquids, but dissolves in organic bases such as pyridin and anilin. It forms an orange-colored crystalline salt with pyridin which loses pyridin on heating to 130°. Rhein melts 318°. Its diacetyl derivative, which is produced on heating with a large excess of acetic anhydride in presence of a little camphor sulphonic acid or pyridin, melts 258°. Diacetylrhein may be removed from its solution in immiscible solvents with sodium carbonate on account of its containing a carboxyl group. When heated with xylene it first dissolves, then suddenly separates on boiling, and in PURGATIVE DRUGS 369 this form is practically insoluble except in alkalies. Rhein dissolves in concentrated sulphuric acid with a red color and is precipitated on dilution. RHEINOLIC ACID Tutin and Clewer 1 separated this acid from rhein by pouring a pyridin solution of the two substances into ether and filtering from the precipitated rhein compound. The ethereal solution yielded the rheinolic acid pyridin compound when shaken with ammonium carbonate. On drying to 130° pyridin was dissipated and the free acid melted 295-297°. It is evidently an anthraquinone derivative. It dissolves in both alkalies and concentrated sulphuric acid with an intense red color, but differs from rhein by not being precipitated from the later solvent on adding water. Its constitutional formula has not been deteraiined. The chief purgative principle of rhubarb is a non-glucosidic resin which Tutin and Clewer found present to the amount of about 10-11 per cent. Of the anthraquinone derivatives only aloe-emodin and chryso- phanic acid have any physiological acitivity the mixture of the glucosides being quite inert. Adulteration of rhubarb with turmeric and hematoxylin can be detected by preparing an alcoholic extract of the product, diluted with water, acidified, and shaken out with ether. On transferring the ether solution to strips of white paper and drying, hematoxylin is indicated if strong hydrochloric acid produces a pink color, and turmeric if boric acid and dilute hydrochloric acid yield the characteristic red tint which is changed to blue by ammonia. Beal and Okey 2 subjected a dilute alcoholic extract of rhubarb to successive shake-outs with 4 parts of ether, benzol, and amyl alcohol. The benzol solution gives a violet-red precipitate with concentrated ammonia. The other anthraquinone drugs will give a red color in the aqueous layer, but rhubarb was the only one which they found yielded a precipitate. If the benzol solution is shaken with solution of lead subacetate, a yellow or orange precipitate is obtained which turns red with alkali. The precipitates of the other drugs remain white. When the amyl alcohol solution is shaken with lead subacetate a red color is obtained. In the case of tho other anthraquinone drugs no change takes place. 1 Proc. Chem. Soc, 1912, 28, 13; 1913, 29, 285. 2 J. Amer. Chem. Soc, 1917, 716. 370 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS SENNA The leaves of Cassia acutifolia and C. angustifolia (Leguminosae) are recognized as the official drug known as senna. C. Marilandica, the American or wild senna, also furnishes an unofficial drug which has a limited use in medicine. C. angustifolia furnishes the Indian or Tinnevelly senna, and the leaves of a variety of this species growing in Arabia are known as Mecca or Arabian senna. The Peruvian senna is also derived from the same species. The Alexandrian senna comes from C. acutifolia, though by some authorities it is regarded simply as a variety of angustifolia. C. holosericia of Abyssinia is known as Aden senna. The leaves of C. obvata are often mixed with those of the other official species. The pods of the senna plants are commercially important, and are employed for the same purposes as the leaves. Senna is used in cathartic mixtures. The powdered drug is one of the components of compound licorice powder where it is mixed with sugar, sulphur, fennel, and powdered licorice root. Compound extract of senna contains also jalap, and coriander, and other liquid mixtures contain, in addition to senna, Taraxacum; Grindelia and rhubarb; Podophyllum, leptandra, and jalap; Spigelia, savine, and manna; rhubarb; sarsaparilla, licorice, sassafras, anise, and methyl salicylate, and sometimes potassium iodide; caraway and coriander; Cascara sagrada, leptandra, juglans, and tartar emetic. Tablet and pill formulas are not numerous, but are of the same type as those containing the other anthraquinone drugs. Pow- dered senna, Cascara sagrada extract, Podophyllum, and magnesia are components of some of the popular laxative tablets and lozenges sold extensively to the laity. The well-known mixtures of the " Castoria " type contain senna, pumpkin seed, chenopodium, anise, rochelle salt, sodium bicarbonate, honey, and sugar, flavored with oil of peppermint and methyl salicylate; and other popular syrups consist of extract of figs and senna with the addition of one or more of the drugs mentioned in the above combinations. Senna leaves are sometimes mixed with the pods. Senna siftings are imported in large quantities and formerly were always heavily adulterated with sand, some shipments containing from 25-40 per cent. Tutin x has made an exhaustive study of senna leaves and reviewed the researches of previous authors. He found that the only anthraquinone derivatives present were rhein and aloe-emodin. In addition to these well-defined constituents senna contains salicylic acid, a volatile oil pos- sessing a characteristic odor, kaempferol, Ci5H 6 02(OH)4, a flavone deriva- tive; kaempferin, a glucoside of kaempferol and glucose; a mixture of * Trans. Chem. Soc, 1913, 103, 2006. PURGATIVE DRUGS 371 the glucosides of rhein and emodin, isorhamnetin melting 302° C, and glucosides of which this is a component; resinous matter from which myricil alcohol, palmitic and stearic acids, a phytosterol and phytostero- lin were isolated; and amorphous substances. Kaempferol (1-3-4 trihydroxyflavonol) is extracted from acid aqueous solutions by ether, and may be extracted from ether by dilute sodium carbonate. As obtained from an extract of the drug it is usually con- taminated with aloe-emodin, from which it may be separated by redis- solving in ether and shaking out with dilute sodium carbonate. By repeating this treatment the aloe-emodin finally will be left behind in the ether. Kaempferol can be crystallized by concentrating its solution in slightly diluted alcohol. It forms bright-yellow needles, melting 274°, colored yellow by alkalies and giving a strong blue fluorescent solution with concentrated sulphuric acid. It yields tetra-acetylkaempferol which when crystallized from ether, ethyl acetate, or alcohol forms colorless needles, melting 119-120°, and when resolidified melts at 183°. This is probably due to the presence of solvent of crystallization, because if the crystals are dried at 110° until no further loss in weight occurs they melt sharply at 183°. E. M. Bailey l considers that chrysophanic acid is a constituent of senna. When an extract of senna slightly acidified is shaken with ether, the ether solution will give the Borntrager reaction. If the ether solution is agitated with saturated solution of nickel acetate, the aqueous layer will develop a red color. On separating and adding potassium hydroxide solution a violet precipitate forms. Beal and Okey find that this reaction is characteristic of senna. Rhubarb and fiangula require the addition of alkali to produce a color change. Cascara gives an orange yellow which becomes dark red after adding alkali. Aloes gives yellow-brown. Henna leaves are obtained from Lawsonia inermis (Lythrariae) and are used in jaundice and for cutaneous disorders, including leprosy. They contain tannins and a yellow substance having powerful dyeing properties. The drug is sometimes confused with senna. CASCARA SAGRADA The bark and fruit of certain species of the Rhamnaceae contain anthra- quinone derivatives and Cascara sagrada or sacred bark from R. Purshiana has attained great renown as a laxative drug. The tree yielding the Cascara bark is indigenous on the western coast of the United States and its habitat extends north into British America. The fluid extracts, both plain and aromatized, are extensively used » Jour. Ind. and Eng. Chem., 1914, 6, 320. 372 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS in medicine, and modified forms of the extract in which the bitter princi- ples have been removed or emasculated by magnesia, are of common occurrence. Cascara cordials contain Berberis aquifolium, and some of the compound extracts contain senna and aloin. Many firms offer a special preparation of Cascara under a fancy, or trade-marked name, in which they claim to have removed the bitter and griping principles of the drug and preserved all of its laxative features. Some of these prepa- rations are highly fortified with other laxative drugs and croton oil. Cascara is combined with malt extract, and with iron peptonate and manganese. It occurs in elixirs with senna, leptandra, butternut, and rochelle salt. In the form of pills and tablets Cascara will be found combined with aloin, strychnin (or Nux Vomica), and belladonna; rhubarb, Nux Vomica, and aloin; Podophyllum, colocynth, Hyoscyamus, butternut, Nux Vomica, gentian and Apocynum; belladonna, Capsicum, Nux Vomica, Euonymus, and Xanthoxylum; Podophyllum, strychnin, aloin, belladonna and ginger; Nux Vomica, belladonna, Podophyllum, and ipecac; Blaud's mass and Nux Vomica; sometimes with arsenous acid; quinin, reduced iron, strych- nin, and arsenous acid. It has been commonly asserted and generally believed, that Cascara bark must be stored for at least a year or two before it can be used, the claim being that fresh bark contains an enzyme which causes intense griping and which is destroyed on long standing. Jowett isolated an hydrolytic enzyme from the bark but found that it had no griping acid. When properly cured, the drug is just as available for producing medicines when it is a month old as when it has been stored for a year or two. The bark of Rhamnus californica sometimes enters into competition with the official drug. The tree occurs abundantly in the southern part of California, while Cascara is found sparingly in that locality. There are recognizable differences in the characteristics of the leaves of the two species, but the appearance of the barks is practically identical. Micro- scopically one will find structural differences sufficiently distinct to aid in the recognition of the drug; and when macerated with dilute alcohol, the powder of R. Purshiana appears yellow, that of R. californica purplish; with potassium hydroxide the former gives an orange-yellow color, the latter a blood red. The chemistry of the bark has been the subject of extended research, but much of the work is of little scientific importance. The bark con- tains resinous material, but this does not appear in large quantity in any of the extracts used in medicine because those extracts are obtained by water percolation. The only definite anthraquinone principle which PURGATIVE DRUGS 373 Jowett isolated from the bark was emodin. He found no chrysophanic acid nor glucosides yielding emodin on hydrolysis. Iso-emodin has been reported. Syringic acid and rhamnol have been reported. An aqueous extract of the bark, after precipitation with lead acetate, contains substances which are thrown out by basic lead acetate and which subsequently, after removing the lead, yield emodin on hydrolysis. Dohme and Englehardt consider that basic lead acetate precipitates a glucoside, to which they give the name purshianin, but Jowett claims that he was unable to detect any glucosidic character in this body. In the course of his experiments with the extract the writer has isolated substances of a glucosidic nature, and while their chemical purity has not been estab- lished it appears probable that the bark contains anthraquinone deriva- tives of a more complex nature than emodin. THE BUCKTHORNS The bark of the stems and branches of the Alder buckthorn, R. fran- gula furnishes the official drug. The barks of R. cathartica, the common buckthorn, and of R. carniolica are probably sold for the official drug, as all of these shrubs grow in the same localities. The berries of R. frangula yield a juice formerly sold as Rhamni Succus. This juice, and that of the berries of R. cathartica, is still used as an hydragogue cathartic in the form of a syrup in combination with ginger and pimento. The combination appears to be useful in dropsy, rheumatism, and gout. The berries of these plants as well as those of R. infectoria and R. santiles are used for making yellow dyes. The frangula barks contain anthraquinone derivatives. Both of the common buckthorns contain a glucoside to which the name frangulin has been given, and which on hydrolysis yields rhamnose and emodin. The emodin of the buckthorn and Cascara sagrada are identical. Fran- gulin resembles the glucosidic substances of Cascara. It is precipitated by basic lead acetate, copper acetate, barium hydroxide, and ferric chlo- ride and gives a red solution with concentrated sulphuric acid. On hydrol- ysis it yields emodin and rhamnose. These drugs also contain flavanol derivatives soluble in concentrated sulphuric acid with a greenish-blue fluoresence. Rhein and chrysophanic acid have also been reported. The anthraquinone derivatives exist in greater quantity in R. fran- gula than in R. Purshiana, but their general character appears to be the same. It is probable that there is but little difference in the chemical constituents of these drugs, though considerable research is still needed to clear up the disputed points concerning their chemistry. Frangula bark gives a much stronger Borntrager reaction than Cascara 374 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS sagrada, in fact the shade is as deep a crimson as that given by senna or rhubarb. When a dilute alcoholic extract of frangula is shaken with 4 parts of ether, and the latter agitated with saturated solution of nickel acetate no red color appears until potassium hydroxide is added to the aqueous layer when a deep red-violet precipitate is obtained, and the ether layer becomes colorless almost immediately. Cascara gives an orange-yellow before adding alkali; the latter then causes a dark red color. With rhu- barb the ether layer remains colored for a much longer period. GOA POWDER AND CHRYSAROBIN Goa powder is an irritant material deposited in cavities in the trunk of the Vouacapoua Araroba (Leguminosse) , a tree growing in Brazil and probably other South American countries. The powder is also known as Brazil powder, ringworm powder, crude chrysarobin, and Pao de Bahia. When fresh it is light yellow and bitter, becoming darker on exposure to the atmosphere. It consists of chrysarobin, gum, resinous matter, and woody fiber, and is often adulterated with powdered Andira wood. Goa powder is used as a remedy for skin diseases and for preparing chrysophanic acid. It is called "Arariba " powder, but this name should be used only to distinguish the barks of Sickingia viridiflora and S. rubra., which are of a different family. Chrysarobin is the name given to purified Goa powder obtained by extraction with chloroform. It is also called medicinal chrysophanic acid and is usually described as the neutral principle of the powder. This description is confusing as it is a mixture of several different substances, some well-defined and others not yet determined, and they are by no means all of neutral character. Chrysarobin is an orange-yellow microcrystalline powder darkening on exposure, soluble in chloroform and benzol with ease, less readily in ether and alcohol and partly and with some difficulty in water. It is soluble in potassium hydroxide to a deep brownish-red solution inclining to purple. It dissolves in concentrated sulphuric acid to a deep red solution. Tutin and Clewer 1 find that chrysarobin contains on the average about 5 per cent of chrysophanic acid, 2 per cent of emodin monomethyl ether, 46 per cent of the anthranol of chrysophanic acid, a small amount of the anthranol of emodin monomethyl ether, 18 per cent of dehydro- emodinanthranol-monomethyl ether, 4 per cent of ararobinol, C23H16O5, and 25 per cent of an inseparable mixture and amorphous material. »Proc. Chem. Soc, 1912, 28, 13, and 1913, 29, 285. PURGATIVE DRUGS 375 The anthranol of chrysophanic acid (chrysophanol) , CisH^Oa, may be represented by the structural formula OH I OH. C .CHs >C 6 H 2 < >C 6 H 3 / oh/ x c / H It forms pale yellow leaves from chloroform, melting 204°. It is insoluble in aqueous alkalies. Its alcoholic solution gives a dark red-brown color with ferric chloride. When treated with chromic acid it is converted into chrysophanic acid. It gives an orange-red color with concentrated sul- phuric acid. Chrysarobin is chiefly employed as an external remedy in psoriasis, herpes tonsurans, and hemorrhoids. It is administered in the form of ointments, cerates, and collodion mixtures. For hemorrhoids it may be combined with iodoform and belladonna, and dispensed in vaseline oint- ments, or in glycerin or cocoa butter suppositories. Acetates of chrysarobin are sold under the names of Lenirobin and Eurobin. The former is described by its makers as a tetracetate, and is soluble in chloroform, acetone, and benzol, but insoluble in water. The latter, a triacetate, dissolves in the same solvents, and is dispensed in acetone. It may be found combined with saligallol (pyrogallol disalicy- late). They are used as substitutes for chrysarobin in skin diseases. DRUGS OF THE RUMEX GENUS The roots of Rumex crispus (Porygonacese), yellow or curled dock, and R. obtusifolius, bitter dock, are used medicinally. The former was official in the U. S. P. 1890. The roots of other species are probably sold indiscriminately with those of the two mentioned. Yellow dock is an alterative, tonic, and mild laxative. It is admin- istered in the form of a syrup combined with potassium iodide, magnesium sulphate, the bark of Celastrus scandens (False bittersweet), the bark and twigs of Parthenocissus quinquefolia (American ivy or Virginia creeper), and the root and plant of Scrophularia marilandica (Maryland figwort or carpenter's square). The solid extract is employed locally in skin diseases and the powdered root as a remedy for spongy gums. The chemistry of the dock roots has never been thoroughly investi- gated, but anthraquinone derivatives are present, and it is claimed that emodin and chrysophanic acid have been identified. The leaves of R. acetosella, the common sorrel or sour grass, are em- ployed in febrile, inflammatory, and scorbutic affections as a refrigerant 376 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS and diuretic drug. They contain acid potassium oxalate and a little tartaric acid. The root of Polygonum cuspidatum syn., Pleuropterus zuccarinii (Poly- gnacese) the Japanese knotweed, is reported as containing free emodin and anthraquinone glucosides. This root has been confused with that of P. bistorta, which is apparently the true bistort and which contains much tannin. Bistort is used in acute and chronic intestinal catarrh, dysentery, amenorrhea, and in hair preparations designed to promote the growth of the hair. Methods for Identifying the Anthraquinone Drugs in Medicines. — It is obvious that there are several important drugs whose most prominent ingredients are anthraquinone derivatives and that in mixtures where they functionate as extracts, the absolute identification of one particular drug to the exclusion of all the others is not an easy matter. Further- more it has been demonstrated that there are several other drugs which contain those or similar derivatives, but whose general chemistry is not known, and which might easily be mistaken for the more common varieties when dispensed in the extract form. The separation and identification of the anthraquinone derivatives is possible only when one has a con- siderable quantity of material, much more than is usually offered as a sample for the analysis of a medicine. In mixtures of powdered drugs the microscopic character of the fibers and cellular structure will aid the analyst in arriving at absolute results, but in liquid or solid extracts where the structural characteristics are lost, he must depend upon the odor, color reactions, and presence of other principles normally occurring in the plant in order to determine the identity of the drug in hand. Often he can go safely only so far in his conclusions as to assert that anthraquinone derivatives are present. Preparations containing rhubarb will give a magenta coloration when subjected to the Borntrager reaction. Senna and frangula extracts also give intense crimson or magenta shades, while Cascara usually gives a lighter color more on the pink, and with aloes the color develops gradually. The essential oil of rhubarb has an unmistakable and characteristic odor and will furnish valuable evidence in establishing the identity of the drug. If an alcoholic extract is mixed with water and distilled with steam, the oil passes into the distillate and is readily recognized. This same odor is always apparent when running an alcohol determination on liquid preparations containing rhubarb. Gallic acid furnishes further evidence of the presence of rhubarb. The fractionation and identification of each and every anthraquinone derivative is impracticable, when working with medicines and about all that one can accomplish is to obtain conclusive tests for their identity. If aloes or aloin are simultaneously present with rhubarb, the odor, ■«■■ PURGATIVE DRUGS 377 presence of gallic acid and strong Borntrager reaction will distinguish the latter, while the odor of the aloes and identification of aloin as described under Aloes will distinguish the former. Reliable tests for senna and the Rhamnus drugs in presence of rhubarb have been worked out by Beal and Okey. Senna contains salicylic acid, which is of course easily separated by petroleum ether from an acid aqueous solution of the alcoholic extract of the mixture, but while this is indicative of the presence of senna it is by no means conclusive. Its absence, how- ever, indicates that there is no senna extract in the preparation, and is a point for the analyst to remember in case he is testifying and the cross- examiner seeks to confuse him regarding the identity of the components of the mixture in hand. Senna also contains kaempferol, which can be separated from the aloe-emodin of the drug as described and then subjected to proper tests for its identity. In ordinary cases under drug control laws it is a small matter analytically whether the drug present is absolutely identified or not. It is sufficient to assert that there was found a drug or drugs containing anthraquinone derivatives, and as these are of limited number and of similar physiological action it matters little analytically whether the formula is composed of one or all of them. The quantitative estimation of the anthraquinone derivatives in these drugs or in mixed medicinal preparations containing no phenolphthalein may be accomplished according to the second method of assay given under Rhubarb, on page 62. Bailey 1 differentiates between the anthraquinone derivatives by pre- paring an alcoholic extract of the sample under examination, evaporating the solvent, diluting with 25 mils of water, precipitating with lead acetate and filtering. The lead precipitate is transferred to a beaker and digested for one hour on a water-bath with 10 per cent sulphuric acid. The solu- tion is filtered and while still hot, is extracted with benzol. The benzol solution is washed first with 25-mil portions of 5 per cent ammonium carbonate until the washings are colorless or but faintly colored, then with similar portions of 5 per cent sodium carbonate until the wash- ings become pink, and finally with 5 per cent sodium hydroxide. He found that ammonium carbonate removed arithraquinone derivatives which he did not identify, sodium carbonate removed emodin and sodium hydroxide removed chrysophanic acid. The three aqueous solutions are ^hen separately acidified, shaken out with ether, and the ether residues examined directly or after recrystallization from alcohol. A few drops of the ether residue is treated with 4 to 5 drops of con- centrated sulphuric acid, then 1 to 2 drops of concentrated nitric acid, and, finally about 1 mil of water. In the case of chyrsarobin a little color is removed by the first two 1 Amer, Jour. Pharm., 1915, 87, 145. 378 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS reagents, but the bulk of the color goes into sodium hydroxide with one washing. The ether residue gives orange red with sulphuric acid, becom- ing yellow with nitric acid and giving a yellow solution and a flocculent precipitate with water. With Rhamnus frangula most of the color is removed by the sodium carbonate and the ether residue gives an intense pink with sulphuric acid, becoming yellow with nitric acid and pink with water. With rhubarb, both the sodium carbonate and hydroxide fractions are colored, the ether residue of the former reacted similarly to the emodin body derived from R. frangula, and the color test with the ether residue from the latter were the same as for chrysophanic acid from chrysarobin. With senna, a considerable quantity of color goes into the ammonium carbonate fraction to an orange-colored solution, and on separation the residue obtained is not homogeneous, being partly insoluble in ether. The ether-soluble portion gives a purple or violet color with sulphuric acid, becoming yellow with nitric acid and remaining yellow on adding water. The ether-insoluble portion gives a purple-red solution with sodium hydroxide which is not discharged by zinc dust, and on dilution with hydrogen peroxide the color fades and a light-colored precipitate settles. Sodium carbonate and hydroxide remove coloring matter from the benzol and the residues finally obtained react for emodin and chrysophanic acid respectively. With aloes, ammonium carbonate removes considerable color, the washings being orange colored. The ether residue gives a purple color with sulphuric acid, turning yellow with nitric acid and unchanged with water, corresponding to the substance obtained from senna. Sodium car- bonate removes but a small quantity of material, and an ether residue gives a red to brownish with sulphuric acid, turning yellow with nitric acid and unchanged by water. The greater part of the color is removed by sodium hydroxide and the ether residue reacts similarly to the chryso- phanic acid obtained from the other sources. Phenolphthalein interferes with the Borntrager reaction and may be removed as the iodin compound by a method evolved by Warren. 1 The preparation in the form of a thick syrup is diluted with water, faintly acidified, and filtered. The filtrate is evaporated to a thick syrup and, while still warm, is extracted with acetone slightly acidified with hydrochloric acid. The acetone extract is evaporated to dryness on a water-bath, the residue twice moistened with alcohol, and the alcohol evaporated in order to remove the last traces of acetone. The residue is dissolved in dilute sodium hydroxide, iodin added, followed by hydrochloride acid, which precipitates tetraiodophenolphtha- lein. After cooling for an hour below 15° C, the iodin compound is 1 Amer. Jour. Pharm., 1914, 86, 444 PURGATIVE DRUGS 379 filtered off, the excess of iodin removed by sodium sulphite, and the solution extracted with benzol to remove the anthraquinone derivatives. One of the most important contributions to the chemistry of these drugs from an analytical standpoint was made by Beal and Okey and to which reference has been made several times in this chapter. A small amount of a dilute alcoholic solution of the drug preparation is shaken with 4 volumes of benzol, separated and the benzol solution shaken with 30 per cent sodium hydroxide. A light red to deep violet color indicates anthraquinone drugs. If the color is due to phenolphtha- lein it will disappear quickly, that due to the other drugs will remain unchanged. If the above test is positive, a portion of the benzol is evaporated, moistened with nitric acid and again evaporated. The residue will be red or orange-red, and when treated with potassium cyanide or 30 per cent alkali will take a red or purplish-red with anthraquinone drugs. Phenolphthalein gives a brownish color. If the latter is present it should be removed by the method of Warren. The dilute alcoholic solution is then divided into three portions, A, B, C. Portion A is shaken with 4 parts of benzol and subsequently with amyl alcohol. A portion of the benzol solution is shaken with concen- trated ammonia, a deep red-violet color with a precipitate of the same color settling between the liquids indicates rhubarb. This is confirmed by the lead subacetate test, yellow-orange precipitate, turning red with alkalies. (If a concentrated alcoholic solution of the drug is precipitated with water, the resinous matter filtered off, washed, dried, and treated in a porcelain dish with alcohol, sodium peroxide, and water, a red color appears in the alcohol, turning orange-red on the addition of water. The other drugs impart no color to the alcohol, but yield various shades of orange with water.) The amyl alcohol shake-out is divided to 4 portions. One portion is shaken with strong ammonia, and the development of a deep-red color and a dark green fluorescence indicates aloes and fresh Cascara. If positive, another portion is shaken with a saturated solution of mercurous nitrate containing a slight excess of nitric acid; in the presence of aloes a deep-red color develops in the aqueous layer, reaching its height in six to eight min- utes, fading to reddish-brown. If a small quantity is present the color is pink. Another portion is evaporated, taken up with dilute alcohol and treated with copper sulphate and hydrogen peroxide and boiled, a red color will appear in presence of aloes. Another portion should be evaporated and tested with borax solution to obtain the characteristic green fluorescent solution. If Cascara is indicated, a portion is evaporated, the film mois- tened with nitric acid, evaporated to dryness, treated with stannous chlo- 380 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS ride containing a little free hydrochloric acid, decanted, washed with jet of water, and treated with alcohol; deep-red color indicates cascara; aloes gives yellow brown. Portion B above is then shaken with 4 parts of ether and divided into several fractions. One portion is shaken with saturated solution of nickel acetate, and if the aqueous layer is red, senna is indicated. If the solu- tion remains green and subsequently gives a green precipitate with potas- sium hydroxide, but preliminary tests have shown a permanent color with alkali, rumex is indicated. (The authors apparently used Rumex eckloni- anus in these researches.) The reagent and the ether must be kept mixed when the alkali is added. When shaken with alkali, a violet precipitate will appear if senna is present; a red- violet precipitate with rhubarb or frangula; and a dark orange-red color with Cascara. Rhubarb and fran- gula give orange solutions before adding alkali. The ether layer after adding alkali, will become colorless almost immediately, except in pres- ence of rhubarb, when it persists. If conclusive evidence is not obtained, a portion of the ether solution is evaporated, nitrated, and treated with stannous chloride as above described. Senna gives a green residue; aloes brown; Cascara red; Rumex, rhubarb, and frangula violet-red; phenolphthalein lemon-yellow. The excess of stannous chloride should be removed with water, the residue treated with U. S. P. solution chlorinated soda, and if a red color appears senna is present. PODOPHYLLUM AND PODOPHYLLOTOXIN The well-known mandrake or May apple, Podophyllum peltaltum (Berberidacese) , is a common plant of the rich woodlands east of the Mississippi. It grows in dense patches and is one of the most conspicuous plants in the early spring throughout its range. The rhizome contains an irritant resin, sometimes called podophyllin, which is extensively used in remedies for liver and bowel complaints. Podophyllum resin is one of the constituents of a great many formulas containing cathartic drugs, and will be found in various combinations with aloin, strychnin, or Nux Vomica, belladonna or Hyoscyamus, Capsi- cum, ipecac, Colocynth, jalap, scammony, gamboge, Cascara sagrada, juglans, gentian, leptandra, oil of peppermint, mercury mass, croton oil, soap, Veratrum, and Apocynum. It enters into the compound cathartic pills of the U. S. P. with colocynth comp., Hyoscyamus, jalap, leptandra, and oil of peppermint; it is combined with santonin, with calomel and sodium bicarbonate; with Hydrastis canadensis; with Euonymus; with Cimicifuga; with quinin or cinchonidin, arsenous acid, Gelsemium, pepper, and ferrous sulphate; and often it is dispensed by itself. PURGATIVE DRUGS 381' It is combined with castor oil in elastic capsules. Fluid extract man- drake compound contains extract of Podophyllum, senna, leptandra, and jalap; and it is present in fluid extract dandelion compound with Tarax- acum and Conium, One of its purified active principles, podophyllotoxin, is used quite extensively as a remedial agent. The valuable constituent of the rootstock is a resin amounting to 3.5-5 per cent, containing podophyllotoxin and picropodophyllin, an isomeric substance. The former is slightly soluble in water, the latter insoluble in water. The resin is intensely irritant to the mucous mem- brane and, unless carefully handled, produces conjunctivitis. The rhizome of P. emodi, a plant growing on the lower slopes of the Himalayas, is larger and yields 11-12 per cent resin, but is only half as rich in podophyllotoxin. The chief constituent of the resin is podophvUotoxin, a neutral sub- stance possessing the formula C 2 oHi 5 6 (OCH3)3+2H 2 0, or C15H14O6+2H2O, crystallizing in prisms, melting 94° C. (117° reported), strongly lsevo- rotatory. When heated with alkalies it is converted by hydration into the salt of an unstable gelatinous acid, podophyllic acid, C15H16O7. This acid loses water and furnishes the crystalline picropodophyllin isomeric with podophyllotoxin, melting 227° and optically inactive. It passes again into podophyllic acid when warmed with aqueous alkalies. Podo- phyllotoxin and picropodophyllin furnish identical decomposition products; when oxidized with nitric acid, oxalic acid is the principal product; when fused with alkalies, orcinol and acetic acid are produced. Both substances contain three methyl groups and no hydroxyl. The yellow coloring matter of the drug is identical with quercetin, the yellow coloring matter of quercitron bark. An amorphous resin called podophylloresin is present in the drug. • Podophyllotoxin is prepared commercially by digesting the resin with chloroform, filtering, concentrating to a thick syrup, and treating with alcohol-free ether as long as a precipitate is obtained. The clear liquid is then decanted and concentrated and the syrupy residue poured into petroleum ether, when the commercial podophyllotoxin is precipitated. An extract of mandrake when subject to Borntrager's test gives a bright-yellow color with ammonia before boiling with acid and an amber color afterwards. This coloration is probably produced by the yellow coloring matter naturally present in the drug. Determination of Resin in the Drug or Extract. — W. M. Jenkins 1 has based a method on the ready solubility of the resin in a mixture of 1 J. Ind. and Eng. Chem., 6, 1914, 671. 382 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS alcohol-chloroform 1-2. Five mils of the fluid extract are shaken with 5 mils of alcohol, 10 mils of chloroform, and 10 mils of acidulated water (0.6 per cent hydrochloric acid). The lower layer is drawn off and the aqueous solution extracted twice with 15-mil portions of the alcohol- chloroform mixture. The united extracts are washed with 10 mils of acidulated water, and the aqueous layer again shaken twice with 15 mils of the solvent mixture. The combined extracts are evaporated and the residue at 100° C. weighed. The drug is first extracted with alcohol by hot maceration and 10 mils of the extract, equivalent to 2 grams of the drug, are treated as described above except that the addition of 5 mils alcohol is omitted. The determination of the podophyllo toxin is often important, but at present the methods in use leave much to be desired. There are two types of procedure, that of the Dutch Pharmacopoeia and the lime method. The former gives about one and one-half times as much podophyllotoxin and is based on the difference in solubility in petroleum ether, after a chloroformic extraction, of the resin and the neutral crystalline principle. The lime method really amounts to a conversion of the podophyllo- toxin to the isomeric picropodophyllin and weighing it as such. The procedure recommended by Gordin and Merrell * is as follows: Five grams of the resin and 10 grams of freshly prepared calcium hydroxide are placed in a strong, well-corked bottle of about 200 mils capacity and the whole weighed. The bottle is then uncorked, heated for a few minutes on the water-bath at 60-65°, 15 mils of alcohol added, the whole well shaken and the closed bottle kept on the water-bath for eight hours, shaking the first few minutes to prevent the formation of a hard lump and then every fifteen minutes. The bottle is then cooled, about 7 mils of chloroform added, then enough of a mixture of 2 parts alcohol-1 chloroform (by vol.) to make the whole liquid weigh 130 grams. After shaking for a few minutes the bottle is allowed to stand for twenty- four to forty-eight hours, 65 grams of the clear liquid drawn off into a tared dish, the solvent distilled off and the residue weighed. JALAP AND SCAMMONY Several species of plants belonging to the Convolvulacese contain purgative resins, which have an extensive medicinal use. The two most important are Exogonium purga (Ipomcea purga), which furnishes the dried tuberous root known as jalap, and Convolvulus scammonia, which furnishes the , gum resin known as scammony. In addition, Ipomcea purpurea contains resinous constituents which are apparently similar, and is sometimes substituted for jalap resin, and the root of I. orizabensis ^roc. Amer. Pharm. Ass., 1902; J. Soc. Chem. Ind., 1902, 1362. PURGATIVE DRUGS 383 (Mexican Scammony) has partially displaced true Scammony. Power and Rogerson 1 have reported an investigation of the tuberous root of I. horsfallise, but the resin therefrom was in small quantity and apparently devoid of physiological properties. JALAP The only constituent of the tuber possessing interest to the drug chemist is the resin. This is obtained by an alcoholic extraction of the ground drug, the residue left on evaporation the solvent being washed and dried. About 10 per cent of this resin is soluble in ether, and about 25 per cent is subsequently dissolved in chloroform. The U. S. P. stand- ard of not over 30 per cent chloroform-soluble matter in resin of jalap is indefinite, as \ariable amounts are removable from the resin according to the method employed. When the resin is stiired with the solvent in the cold, it is not completely extracted after nineteen or twenty additions of chloroform, and the large number of fractions required renders the procedure impracticable. The quantity dissolved in the cold by this method is much less than that taken up by hot chloroform when the sample is subjected to a Soxhlet oi Knorr extraction. In fact some samples of jalap resin yield over 90 per cent to the solvent, when subjected to the Soxhlet method. The adulterants of jalap resin include colophony, guaiac, myrrh, Tolu balsam, and the resin from aloes, jalap stalks, and Fungus Laricis (Dieterich). Jalap resin is used in several well-known cathartic mixtures dispensed in the pill or tablet form. In the liquid form, extract of jalap is combined with the extracts of Podophyllum, senna, leptandra in fluid extract man- drake compound; and with senna and coriander in fluid extract senna compound. The types of pill mixtures contain in addition to jalap resin, colocynth comp., colocynth, aloes, cardamom, scammony, soap, Podo- phyllum, Capsicum, and Hyoscyamus; leptandra, aloin, Podophyllum, gamboge, Capsicum, Hyoscyamus, and peppermint oil; similar formulas with Nux Vomica or gentian or calomel, or rhubarb; liver pills with aloes, gamboge, leptandra, Capsicum, Veratrum viride, croton oil, calomel, or Podophyllum; aloes, mercury mass, and tartar emetic; and the U. S. P. vegetable cathartic consisting of colocynth comp., Hyoscyamus, jalap, leptandra, Podophyllum, and peppermint oil. The chief portion of jalap resin is insoluble in ether and is commonly designated as " convolvulin," and the ether soluble portion as " jalapin," though originally the latter term was applied to the chief portion of the resin, which was insoluble in ether. These terms have little significance 1 Am. J. Pharm., 1910, 82, 355, 384 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS at the present time, however, as Power and Rogerson have published the results of a carefully conducted research, the essentials of which may be summarized as follows: The total crude resin, when purified by means of animal charcoal, had a specific optical rotation of —37.0°. On extracting the crude resin successively with (I) light petroleum (b.p. 40-60°), (II) ether, (III) chloroform, (IV) ethyl acetate, and (V) alcohol, a number of products were obtained, the examination of which has shown the resin to be of much more complex composition than has previously been assumed. I. Petroleum Extract of the Resin. — This represented 1.9 per cent of the total resin. It contained palmitic and stearic acids in a free state, and, after hydrolysis, yielded formic, butyric, and higher volatile acids, palmitic acid, and a mixture of unsaturated acids, which appeared to consist chiefly of linolic acid. From the unsaponifiable portion of the extract there were obtained a phytosterol, C27H46O (m.p. 134-135°, (a) D — 32.4°), cetyl alcohol, C16H34O, and a small amount of a substance melting at 56-57°, which agrees in composition with the formula C18H36O. This substance, which appears to be a new compound, yields color reac- tions similar to those of the phytosterols. II. Ether Extract of the Resin. — This represented 9.7 per cent of the total resin. From it there was isolated a small amount of a new, dihydric alcohol, which possesses the formula C2iH3202(OH)2, and is designated ipurganol. Ipurganol crystallizes in colorless needles, melting at 222- 225°, and has, in pyridin solution (a) D — 44.9°. It yields color reactions similar to those given by the phytosterols. Diacetylipurganol, C2iH320 4 (CH3-CO) 2 , forms colorless leaflets, melting at 166-167°, and has, in pyridine solution, (a) D — 36.0°. The ether extract, after treat- ment with alkalies and dilute sulphuric acid, yielded, furthermore, a little phytosterol and acetyl alcohol, small amounts of volatile acids, and a quantity of amorphous products. III. Chloroform Extract of the Resin. — This represented 24.1 per cent of the total resin. From it there was isolated a very small amount of /S-methylsesculetin, C 9 H 5 (CIl3)04. After treatment with alkalis and dilute sulphuric acid this extract yielded, furthermore, formic, butyric, and d-methylethylacetic acids, together with convolvulinolic acid, C15H30O3, and apparently a higher homologue of the latter. Glucose was also produced by this treatment, thus indicating that a portion of the extract was of a glucosidic nature. IV. Ethyl Acetate Extract of the Resin. — This represented 22 per cent of the total resin. On treatment with dilute alcoholic sulphuric acid, it yielded formic, butyric, and d-methyletlrylacetic acids, together with convolvulinolic acid, and apparently a higher homologue of the latter, having the composition C17H34O3. It also yielded, besides indefinite PURGATIVE DRUGS 385 amorphous products, a considerable quantity of a sugar, which was evi- dence that at least a portion of the extract was of a glucosidic nature. V. Alcoholic Extract of the Resin. — This represented 38.8 per cent of the total resin. After treatment with animal charcoal it was obtained in the form of a nearly white powder, which melted at 150-160°, and had (o)d— 37.1°. When fused with potassium hydroxide it yielded formic, acetic, butyric, valeric, and higher volatile acids, together with azelaic and sebacic acids. When subjected to alkaline hydrolysis with baryta it yielded, besides small amounts of formic and butyric acids, d-methyl- ethylacetic acid, C 5 Hi O 2 (b.p. 174-176°; («)/>+ 17.55°), together with a quantity of an amorphous product, readily soluble in water, which may be designated as the hydrolyzed resin. This has now been shown to be of very complex composition, for by successive extraction with (a) ether, (b) chloroform, (c) ethyl acetate, and (d) alcohol it is capable of being resolved into a number of products. (a) Ether Extract of the Hydrolyzed Resin. — This extract, on heating with dilute sulphuric acid, yielded formic, butyric, and other acids, together with sugar. (b) Chloroform Extract of the Hydrolyzed Resin. — This extract, like the preceding one, yielded small amounts of formic, butyric, and other acids, together with sugar. (c) Ethyl Acetate Extract of the Hydrolyzed Resin. — This extract, on heating with dilute sulphuric acid, yielded formic, butyric, d-methylethyl- acetic, and other acids, together with sugar. (d) Alcohol Extract of the Hydrolyzed Resin. — This extract could be obtained in the form of a nearly colorless powder, which melted at 110— 115°, and had {a) D — 33.53°. When heated with dilute sulphuric acid it yielded, in addition to sugar, small amounts of formic, butyric, and valeric acids, together with convolvulinolic and ipurolic acids. The last mentioned acid possesses the formula Ci3H 2 5(OH)2-C02H, and was first obtained by the authors from the stems of Ipomcea purpurea, Roth. 1 By the oxidation of this extract with nitric acid, azelaic and sebacic acids were obtained. Each of the above-described extracts of the hydrolyzed resin appeared to be only partly glucosidic, and to contain a readily soluble organic acid which was unaffected by the treatment with dilute sulphuric acid. Scammony The gum-resin, obtained by incision of the horny root, is commonly designated as scammony or virgin scammony. Its value as a purgative agent depends on its resinous constituent, which is now generally obtained 1 Am. J. Pharm., 80, 273 (1908). 386 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS by extracting the dried root with a suitable solvent and washing the resinous mass with water until it comes away clear. The resin obtained by this means is almost completely soluble in ether, and the ether soluble portion has been termed " scammonin," being synonymous with the " jalapin " or ether soluble portion of jalap resin. Scammony resin is not used as largely as jalap, but it will be found in cathartic pills and tablets combined usually with colocynth, and con- taining in addition Podophyllum, soap, aloes, cardamom, and potassium sulphate. It is one of the ingredients of powdered extract colocynth compound, and as this product enters into the composition of a large variety of formulas the presence of small quantities of scammony may be expected whenever colocynth is discovered. Power and Rogerson 1 examined the root of Convolvulus scammonia, and found it to contain about 10 per cent of resins. They also identified sucrose, scopoletm, melting 203-204°, giving a beautiful blue fluorescence with alkalies, and 3-4 dihydroxycumaric acid. The resin which they obtained by alcoholic extraction was soluble to the extent of 90-95 per cent in ether, and thus differed markedly from the resin of jalap. Its rotation in absolute alcohol was (a) D — 19.87°. It has a peculiar and characteristic odor which is brought out on warming or by rubbing in a mortar. The resin yielded a phytosterol, melting 135-136°, soluble in petroleum ether, compounds of palmitic and stearic acid, ipuranol, C33H56O6, and on hydrolyzing with barium hydroxide, d-a-methyl butyric, tiglic, formic, and valeric acids, meth yl jalapinolate f| melting 47-49°, and jalapinolic acid, melting 67-68°, a mixture of sugars, and indefinite bodies. Ipuranol appears to be a phytosterol glucoside which on hydrol- ysis with aqueous hydrochloric acid is resolved into a phytosterol, C27H46O12, and glucose. The same authors examined virgin scammony and found it to be soluble to the extent of 80-85 per cent in ether, and to contain in addition to the substance mentioned above, small amounts of hentriacontane C31H64, and cetyl alcohol. The saponification number of the resin runs from 230-240 (Taylor) or 263 (Cowie). Scammony resin is adulterated with rosin, chalk, starch, resinous material and extractives from other drugs and Dieterich reports a case of adulteration with lead sulphide. Mexican Scammony The root of I. orizabensis is known under various names, such as Light, Fusiform, or Woody Jalap, or Orizaba Root (see Holmes, Pharm. J., 1904, 72, 326). 1 Chem. Soc. Trans., 101, 1912, 398. PURGATIVE DRUGS 387 It contains about 15 per cent of crude resin, of which from 70-75 per cent is soluble in ether. Power and Rogersons' 1 investigation of this drug may be summarized as follows: From the portion of the extract which was soluble in water, the follow- ing compounds were isolated: (1) scopoletin, CioHgC^ (m.p. 203-204°), a small proportion of which appeared to be present in the form of a gluco- side; (2) 3:4 dihydroxyciimajiiic acid, CgHsO^ (m.p. 223-225°), from which the methyl ester (m.p. 158-160°) was prepared. The aqueous liquid contained, furthermore, a quantity of sugar, which yielded d-phenyl- glucosazone (m.p. 205-206°). The portion of the alcoholic extract which was insoluble in water consisted of a resin which possessed the above-mentioned characteristics. The resin was first successively extracted with various solvents, and the resulting extracts were then further examined. I. Petroleum Extract of the Resin. — From this extract the following substances were obtained: (1) hentriacontane, C31FL34; (2) a phytosterol, C27B46O; (3) cetyl alcohol, C16H34O; (4) a mixture of fatty acids, con- sisting of palmitic, stearic, oleic, and linolenic acids. II. Ethereal Extract of the Resin. — The optical rotatory power of this extract was (a) D — 20.5°. After hydrolysis with barium hydroxide it yielded: (1) ipuranol, C23H3s02(OH)2; (2) (/-a-methylbutyric acid; (3) tiglic acid; and a product which on acid hydrolysis, gave (4) jalap- inolic acid, CioHsoCOH) -C0 2 H (m.p. 67-68°); (a)z>+0.79°), together with a little methyl jalapinolate, and (5) a mixture of sugars, consisting of dextrose and a methylpentose. The latter yielded an osazone melting at 180-182° and a tetra-acetyl derivative, C 6 H s 5 (CO-CH3)4, which apparently is a new compound. Tins derivative crystallizes in handsome, prismatic needles, melting at 142-143°, and has (a).o+21.64°. The ethyl acetate extract of the product resulting from the alkaline hydrolysis of the ethereal extract of the resin gave on oxidation with nitric acid a mix- ture of acids, consisting apparently of optically active valeric and hexoic acids, together with sebacic and n-nonanedicarboxylic acids. III. Chloroform Extract of the Resin. — This was relatively small in amount, and consisted of a dark resinous product. IV. Ethyl Acetate Extract of the Resin. — The optical rotatory power of this extract was (a) D — 28.01°. After hydrolysis with barium hydroxide it yielded products from which the same substances were obtained as from the ethereal extract of the resin, with the exception of the small amount of ipuranol. V. Alcohol Extract of the Resin. — This was a black, amorphous prod- uct of a glucosidic nature, but which yielded nothing definite on hydrolysis. iChem. Soc.'Trans., 1912, 101, 1. 388 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS It may also be noted that the portion of the resin which is soluble in ether is not identical with the ether-soluble portion of jalap resin. It has a saponification value of about 186-188 (Taylor) 295-327 (Cowie). While there are some minor differences between the composition of the resin of this root and that of C. scammonia thus far ascertained, it is apparent that the resins could readily be substituted for each other with little chance of certain detection and as will probably be demonstrated, they are equally valuable for medicinal purposes. IPOMOEA TTJRPETHUM The root of I. turpethum, an East Indian species, yields a gum resin similar to jalap resin in its properties. This resin is called Turpeth and is used medicinally. Reports of its composition have appeared, but they require confirmation and further research. It is soluble in alcohol but insoluble in ether. Dieterich reports the following constants: acid value 20.55-24.45; ester value 137.27-141.01; saponification value hot 160.49-163.94. Examination of Resins. — In order to test these resins for adulterants a few simple determinations should be made and the results compared with those obtained with authentic specimens. Cowie recommends the following tests for Jalap resin, the same pro- cedure being applicable to the others: 1. Moisture. 2. Ash. 3. Solu- bility in ether, obtained by rubbing the sample in a mortar with ether, filtering and evaporating the solvent in a tared dish. 4. Acid value, obtained by dissolving in alcohol and titrating. 5. Saponification value. One hour's boiling with N/2 alcoholic potash and titration with N/2 hydrochloric acid. 6. Absence of colopheny, .25 gram in 5 mils acetic anhydride should give no purple color with 2 drops of strong sulphuric acid. 7. Absence of guaiacum, no greenish-blue color with ferric chloride. 8. Treatment with water results in no water soluble substance nor any starch reaction. Cowie 's results obtained by applying these tests to authentic resins yielded the following data: Brown Jalap resin Cowie White Jalap resin . . White Scammony resin . . . Brown Scammony resin . . . Mexican Scammonv resin. Moisture, Per Cent. O-o. b 3-3.1 2.52-5.3 4.5-5.1 2-3 . 05 Ash, Per cent. 0.3 0.02 0.02 .15 16-. 20 Ether Soluble, Per cent. 10 0.3 100.0 95 68.6-72 Acid \ alue. Sapon. Value. 11 2.8 2.8 25.2 8.4 2-14 -28 333-338 417 241 263 295-327 PURGATIVE DRUGS 389 Taylor's 1 results below with true and Mexican Scammony resins do not agree with Cowie's, but the differences may be due to the methods of analysis. Taylor dilutes with water before titrating with acid to determine the saponification value. Moisture, Per Cent. Ash, Per Cent. Ether Soluble, Per Cent. Acid Value. Sapon. Value. True Scammony Mexican Scammony. 1.65-1.86 1.77-2.03 05-. 20 09-. 22 99-99.7 96.5-99.6 15.6-21.3 15.5-21.5 238-240 186.6-187 Evans Sons, Lescher, and Webb consider that the ester value of the resin is the most important factor in differentiating the source. They report the following data: Acid Value. Sapon. Value. Ester Value. Iodine Number. Jalap Virgin Scammony. . . Mexican Scammony 8.4-26 7-12 11.2-24.1 144.8-185 240-250 172.5-202.7 121.8-162 233-242.7 161.3-178.6 9-24.2 3.6-9.6 8.3-15.3 Boudier 2 states that pure scammony resin should not give an acid number above 21 nor a saponification value below 235. Weigel 3 gives Asiatic scammony resin an acid number from 14-28, a saponification value 179-228; and Mexican Scammony 14.6 and 180-185. Jalap resin, acid number 12.6-16.8, saponification value 162-185. He considers that the acid value has greater significance than the saponifica- tion value. It has been suggested that the specific rotatory power might aid in detecting adulterants in, and discriminating between these resins. The resin obtained by extracting scammony root with a solvent has a rotation varying from —18° 30' to —23° 30' and the upper limit for the resin from the natural scammony is —25°. Mexican scammony rotates from —23° 30' to -25°. The rotation of jalap resin is -36° to -37°, that of I. turpethum is high and that of I. purpurea —50 to —95°. The addition of colophony, sandarac, or mastic would lower the rotatory power, as their direction is dextro. It is apparent from the preceding review of the resins of the Convol- vulacese that their absolute identity in complex mixtures with other drugs is a matter of considerable difficulty. They are usually accompanied by other resinous drugs, and, while as a rule a mixture containing jalap will 1 Am. J. Pharm., 1909, 81, 105. 1 J. Pharm. Chem., 5, 97 and 154. 3 Pharm. Zentralhalle, 51, 721. 390 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS not contain scammony, jalap preparations often include extract of colo- cynth compound which has a little scammony in its make up. In the general scheme of analysis the resins will be extracted from the sample by alcohol, and, on driving off the solvent and treating the residue with water, they will be left behind in the dish. If this resinous mass is completely soluble in ether, the absence of jalap is established, but not necessarily the absence of the commercial " jalapin." If a residue is left undissolved, it may be freed from ether by warming and a portion treated with concentrated sulphuric acid, which will produce a brown to blood- red with a noticeable jalap-like odor if the drug is present. The balance of the residue is treated with chloroform and filtered, the chloroform solu- tion shaken with sodium carbonate, which will show a marked blue fluores- cence due to j3-methylaesculetin. This reaction can be rendered more certain by drawing off the alkaline solution, acidulating, filtering, and shaking with ether, discarding the acid liquid, and finally shaking the ethereal solution with ammonia, when a fine blue fluorescence will be obtained. A similar reaction will be obtained if Gelsemium is present in a mixture, but this drug can be readily distinguished from jalap by its characteristic alkaloids. That portion of the resinous matter which is soluble in ether will con- tain scammony and on evaporating the solvent and warming the residue with sodium carbonate solution it will not entirely dissolve, and the insoluble portion after washing and drying will swell up to a yellow mass with nitric acid. There are no methods for the accurate quantitative determination of resins or for separating one from the other. It is easy to determine the total amount of resinous matter in a drug mixture, but as nearly every vegetable drug contains some material of this nature, and as jalap and scammony are usually combined with other drugs, any estimate of resin will under such conditions be of little value. CHAPTER XII MISCELLANEOUS ACTING DRUGS SANTONIN AND PRINCIPLES OF THE ARTEMISIAS AND CERTAIN ALLIED DRUGS The genus Artemisia of the tribe Anthemidea? (Composita?) embiaces over two hundred species, some of which are of value as medicinal agents. The flowering tops of A. cina, A. maritima, A. gallica, and perhaps others contain santonin, a substance of peculiar lac tone-like composition which has a specific action on ascarides and lumbricoids. On this account san- tonin has become an important remedy for the expulsion of worms, and the ground drug, called Santonica (the true Levant wormseed), is exten- sively employed in stock remedies. It is evident that a great deal of Santonica is devoid of santonin, and that the drug as imported into the country may contain anywhere from 3.5 per cent to nothing. It is not unlikely that the flowering tops of other species of Artemisia are shipped indiscriminately for Santonica. A. absinthium is the well-known wormwood, which is supposed to be one of the ingredients of absinthe. This species, as well as half a dozen others growing in this country, are employed as bitter tonics and stomachics and sometimes as emmenagogues, antiperiodics, diuretics, anthelmintics, etc. Nearly all of the Artemisias growing in North America are called wormwood, hence it would not be surprising if twenty or more different species were collected and marketed. A. absinthium contains thujone and absinthiin, the former a volatile ketone winch gives a characteristic property to the oil of wormwood, and the latter a bitter principle, perhaps of glucosidal nature. Of the other species we may mention A. abrotanum, southernwood, A. frigida, wild or mountain sage, A. pontica, Roman worm- wood (which must not be confused with Ambrosia artemisiaef olia) , A. vulgaris, mugwort or motherwort, and A. inert ellina, silky wormwood from the Alps and Central Europe. A. absinthium is the only one whose composition has received any attention, and the chemistry of that is in need of revision and amplification. While it is supposed to be used in the manufacture of the liqueur "Ab- sinthe," and the deleterious properties of the drink credited to its pres- ence, it is doubtful if a careful and sane investigation would sustain these convictions. The writer had occasion at one time to investigate samples 391 392 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS of all of the brands of Absinthe then being imported, as well as some of those made in this country, and as a result it appeared that in but one case was there any suggestion of a bitter principle resembling absinthiin, and the amount of thujone and oil of wormwood was in too small amount to yield any characteristic reaction. However, the ban was placed on imported " Absinthe " because it was deleterious to the health of the people of the United States, which it probably was because of its alcohol content, in the same way that all imported whiskies, wines, and cham- pagnes might be considered deleterious. Allusion was made above to Ambrosia artemisisefolia syn., A. elatior, which belongs to another family, the Ambrosiacea. This is the well- known Roman wormwood or ragweed of waste places and cultivated fields, and which is credited with being one of the aggravating causes of hay fever. Its extract has been recommended as a remedy for asthmatic conditions. A serum called Pollantin is prepared from the " serum toxin " of ragweed and is used locally in hay fever. There is another drug, Chenopodium or American wormseed, which can be considered to advantage with this group, both because of its use and the character of its active principle. The drug American wormseed is the fruit of Chenopodium ambrosioides (Chenopodiacese, Goosefoot family) (Syn. C. anthelminticum) . The fruit and oil distilled therefrom are official in the Pharmacopoeia. An extract of the drug is used in the preparation of combination worm remedies and laxatives for children and the oil, which consists largely of ascaridol, is a valuable vermifuge. To sum up the pharmacognosy of these paragraphs: Artemisia maritima and A. cina Levant wormseed: Santonica A. absinthium Wormwood Absinthe A. pontica Roman Wormwood (Not the common Roman wormwood of waste places and fields.) Ambrosia elatior syn. arte- Roman wormwood Ragweed misiafolia. Chenopodium ambrosioides American Wormseed syn. anthelminticum SANTONICA Santonica is used in the preparation of condition powders for stock. Its anthelmintic principle, santonin, is a popular remedy and is dispensed in tablet or lozenge form either by itself or in combination with calomel or podophyllin or both. The amount of santonin varies with the age of the bud and the individ- ual plant. It is supposed to be greatest just before the expansion of the flowers. For its determination in the drug the analyst is referred to page 64. MISCELLANEOUS ACTING DRUGS 393 Santonin, C15H18O3, crystallizes from dilute alcohol in pearly crystals, melting 171-172°. When dissolved in chloroform, the solvent on evapo- ration leaves a colorless syrup which crystallizes in feathery, frostlike radiating groups. When cautiously heated, santonin may be sublimed, but there is no danger of loss from drying at 100°. It gradually turns yellow on exposure to sunlight. Santonin is only slightly soluble in cold water, but is somewhat more soluble in boning water. It is fairly soluble in cold alcohol and ether and with ease in chloroform and boiling alcohol. It can be completely removed from an acid mixture by means of chloroform, but it is not removable by alkalies from its solution in organic solvents. It dissolves in alkalies, but the solution cannot be titrated to determine the santonin. Santonin is strongly lsevorotatory. (a) ^—173.8 for alcohol and — 171.4 for chloroform. It is neutral to litmus. Solutions of santonin are not precipitated by ordinary alkaloidal pre- cipitants, but the solid substance gives a few characteristic color tests. It dissolves in concentrated sulphuric acid with a yellow color, the isolated crystals being surrounded with a violet ring, as they join the solution; if this solution is then diluted with an equal volume of water and treated with ferric chloride a violet color is produced. Nitric acid produces no characteristic reaction, but on evaporating and adding alcoholic potash an intense orange color results. Santonin itself gives a red color with alcoholic potash. Santonin has the property of affecting the vision to such an extent tnat everything appears yellow. Santonin is the lactone of santoninic acid, C15H20O4, a derivative of naphthalene. The constitution of the lactone is probably CH 3 I H 2 0=C C CHCHCH3 ")>c=o / H 2 C C CHO I H 2 CH 3 Santoninic acid may be obtained by treating santonin with alkalies, and after solution has taken place an excess of hydrochloric acid is added and the acid immediately shaken out with ether. It reverts to santonin if allowed to stand in contact with mineral acid, or when warmed to 120°. It crystallizes in rhombic crystals from alcohol and has an acid reaction. 394 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Santonic acid, an isomer and much more stable than santoninic acid, is prepared by boiling santonin twelve hours with barium hydrate solution, acidifying with hydrochloric acid, and shaking out with ether. It forms rhombic crystals, melting 163°. Artemisin or oxysantonin, melting 202°, accompanies santonin in the drug. In analytical work it is not difficult to distinguish santonin from the other principles present in medicinal compounds. It is very sparingly soluble in acid aqueous solutions and may be separated from acid mixture with ease by chloroform. It is soluble in alcohol and crystallizes from dilute alcohol, melting 171-172°. Its color reactions are characteristic, and it gives negative tests with most of the reagents used for distinguish- ing the alkaloids and other commonly occuring substances. Determination of Santonin in Tablets. — Transfer 8 tablets to a small Squibb separator, and moisten with water (5 mils); add 2 drops dilute sulphuric acid. Shake out three times with 25-mil portions of chloroform, collecting each shake-out in another separator. Wash the combined chlorof ormic solutions with 5 mils of water, and when the water has entirely risen to the surface and no minute bubbles are seen through the mass of the liquid, run the chloroform into a tared beaker, through a pledget of absorbent cotton in the stem of the funnel. Evaporate the chloroform over the water-bath, using a fan, and when solvent has evaporated, dry for fifteen minutes in water oven. Weigh directly as santonin. With calomel present, the above procedure is not satisfactory, owing to the emulsifi cation which takes place when calomel, chloroform, and water are shaken together. The determination should be conducted in a 25-mil graduated cylinder with lip. Introduce 8 tablets and crush with a stout stirring rod. Add 20 mils chloroform and stir mixture with the rod. Filter the chloroform through a good grade of dry paper, free from pinholes, into a tared beaker. Repeat twice, then evaporate chloroform and finish determination as above. Calomel is insoluble in dry neutral chloroform. ABSINTHIIN AND ARTEMISIA Artemisia absinthium is used as a tonic and stomachic and it will sometimes be found in hniments mixed with menthol, oils of sassafras, calendula, and Echinacea angustifolia. Absinthiin is the bitter principle. It appears to be a glucoside, but its chemistry needs further study. The purified substance has been described as consisting of white inodorous crystals having the compo- sition C15H20O4, and melting 68°. It is reported as yielding dextrose on acid hydrolysis, and phloroglucinol when heated with alkali hydroxides. The chemist should not depend on this meager description for the MISCELLANEOUS ACTING DRUGS 395 characteristics of the bitter principle of wormwood. An extract of the true drug will always contain thujone, which lends itself much easier to detection, and whose properties are now well known. An acid aqueous solution obtained by digesting an evaporated alcoholic solution of worm- wood with water and acidulating, will yield a vitreous bitter residue to petroleum ether and to ether. Probably both of these residues contain absinthiin. If the chemist suspects the presence of this drug, a portion of the same should be distilled with steam and the distillate examined for thujone, while the residue is evaporated to dryness, extracted with alcohol, the alcoholic solution separated and evaporated and) the residue taken up with warm water which is then acidulated and shaken out with petroleum ether and with ether. If there is any appreciable quantity of the drug present in a medicinal compound it is recognizable by its odor, provided this is not masked by the aroma of high-scented flavoring oils. The test for thujone with sodium nitroprusside and acetic acid is of course a general reaction for ketones and ought not to be conclusive. Many other oils have been found to give the same reaction with sodium nitroprusside as oil of wormwood, namely, hyssop, calamus, verbena, and savine. ASCARIDOLE AND AMERICAN WORMSEED The drug known as American Wormseed consists of the fruit of Cheno- podium ambrosioides syn. anthelminticum. Its extract is employed as a worm remedy and is dispensed with extract of senna, Cascara sagrada, pumpkin seed, Rochelle salt and sodium bicarbonate in a class of medi- cines of the " Castoria " type, which are recommended as laxatives and worm expellants especially for children. The oil of Chenopodium is official in the Pharmacopoeia and consists of about 70 per cent of ascaridole, which seems to be the anthelmintic principle. Ascaridole will of course be found in the fluid extract. Ascaridole is an organic peroxide which has been assigned by Wallach the constitution CHa H 2 C H 2 C I I I C3H7 CH CH 396 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS It boils 96-97° under 8 mm. Specific gravity .9985 at 20° C. n D at 20° — 1.4769, sometimes slightly laworotatory, probably due to impurity. It is explosive when heated or when treated with concentrated mineral acids. On shaking with nearly saturated ferrous sulphate at a tempera- ture below 30°, a viscous product, ascaridol glycol, is obtained, which boils 271-272°. If the reaction is allowed to proceed without cooling, basic ferric sulphate will be precipitated and a combustible gas evolved. Ascaridole will not react with the reagents used to characterize the alcohols, ethers, ketones, aldehydes, and acids, but it is soluble in the ordinary organic solvents, and though it is present in the children's remedies in small quantity, its indifference to reagents will allow of its separation from other ingredients to such an extent that tests for its explosiveness can be applied. RAGWEED OR ROMAN WORMWOOD There are as yet no published data on the chemistry of Ambrosia elatior. The alcoholic extract has been used in conjunction with extract of Solidago species (golden rod) as a remedy for hay fever and asthma, but its application in this way is limited. Of late years it has been suggested that the plant gives off an albumen which has a toxic action on the mucous membrane. Based on this theory a serum has been prepared which when applied locally is stated to be of value in alleviating hay fever. Pollantin, Fall — Dunbar's Serum. — Antitoxic serum from horses treated with pollen toxin derived from ragweed. Horses are injected with gradually increased doses of pollen toxin (derived from ragweed), which results in the formation of an antitoxin after two or three months of treatment. The horses are then bled and the strength of the serum is estimated by determining the proportion which will prevent the action of a solution of pollen toxin, of which one drop is barely sufficient to produce a reaction when instilled into the conjunctival sac of a hay-fever patient. The serum is preserved by the addition of 0.25 per cent of phenol. It is a clear, slightly yellowish liquid, having the odor and taste of a dilute solution of phenol. On standing, the liquid deposits a slight pre- cipitate. The liquid is alkaline in reaction and not irritating to the normal conjunctiva. Pollantin, Fall, has no pharmacologic action except the neutraliz- ation of the pollen toxin. The serum is not intended for use hypodermic- ally. It is employed for the relief of hay fever and it seems to be effective in a proportion of cases. It may be used as a prophylactic. Pollantin Powder, Fall. — A powder obtained by evaporating, in vacuo, MISCELLANEOUS ACTING DRUGS 397 pollantin serum derived from ragweed toxin at about 45° C, and mixing it with sterilized sugar of milk. It is a fine, slightly yellowish, almost odoness powder, almost but not entirely soluble in water, and having a slight alkaline reaction. The tests are the same as for the liquid. It should reduce Fehling's solution. The powder is applied to the eyes by dusting on the conjunctiva and to the nose by snuffing into one nostril, the other being closed, a piece as large as a lentil. ASPmiUM The official drug called Malefern consists of the rhizome of Dryopteris Filix-mas syn. Aspidium Filix-mas (Polypodiacese) , true malefern, or of D. marginalis, evergreen wood-fern or marginal shield fern. The extract of this drug, or more commonly its oleoresin, is used in the removal of tape worm, and is usually administered with castor oil and kamala. Malefern oleoresin is often adulterated with castor oil. This prod- uct, which is also known as liquid extract of malefern, is of an oily con- sistency, obtained by an ether extraction of the drug. It has a specific gravity of 1.018-1.052, refractive index 1.4995-1.5157, saponification value 227-259, unsaponifiable matter 4 to 7 per cent, material insoluble in petroleum ether 3 to 15 per cent, crude filicin 19 to 28 per cent, as deter- mined by the method of the Swiss Pharmacopoeia. The potash extract of oleoresin malefern is that portion of an ether solution of 20 grams soluble in 1 per cent potassium hydroxide. It contains acid constituents. The potash insoluble is that which remains in the ether and in genuine samples it amounts to about 50 per cent. The acid number of the potash insoluble portion is 28 to 36 in genuine samples but runs up as high as 149 if castor oil is present. The Swiss method is as follows: Five grams of the extract are transierred to a 200-mil flask, 30 grams of ether added, followed by 100 grains of 3 per cent barium hydroxide, the whole well shaken, transferred to a separatory funnel, and allowed to stand ten minutes. The aqueous portion is filtered, 86 grams of the filtrate treated with 3 mils of hydrochloric acid, or sufficient to render it acid, and then shaken with 30-20-15 mil portions of ether. The com- bined ether extracts are filtered, the filter washed with ether, and the sol- vent solution evaporated in a tared dish, drying to constant weight at 100° C. The residue should weigh 1.04 to 1.12 grams, corresponding to 26-28 per cent crude filicin in the extract, 398 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS FILICIC ACID AND RELATED SUBSTANCES The most recent work indicates that Aspidium probably contains the following constituents, in approximately the amount indicated: Filicic acid, 3.5 per cent; flavaspidic acid, 2.5 per cent; albaspidin, 0.05 per cent; aspidinol, 0.10 per cent; flavaspidin, 0.10 per cent; amorphous acid, 5.0 per cent and filicic nigrine, 6.0 per cent. These substances are, for the greater part, derivatives of phloroglucinol, and some of them are ketones possessing acid characters. The various formulas assigned to the filicic acids and the different results reported regarding their physiological activity have given rise to much confusion, leaving the chemistry in an unsettled condition. One of the first formulas assigned to filicic acid is that of Luck — C26H30O9, which differs considerably from the formula C^HigOo — given this sub- stance by Grabowski, and C14H16O5, as suggested by Daccoma. Later two forms, a crystalline and an amorphous filicic acid, were recognized by Poulson, who suggested the formula, C36H40O12, for the crystalline filicic acid and C36H42O13 for the amorphous acid, which later he considered as the active therapeutic principle of aspidium. Poulson believed the crystalline acid to be the anydride of the amorphous acid. More recently, Gallas has stated the formula for both the crystalline and the amorphous filicic acid to be C18H22O6. Gallas and later Kraft concluded that one form of the acid was 'the lactone of the other form. Filicinic acid, which has the formula CgHieOs, is sometimes confused with filicic acid. Besides a difference in the theories regarding the constitution of the various filicic acids, there has been considerable controversy over the anthelmintic properties of these substances. Amorphous filicic acid is an organic acid, C36H42O13, obtained from several species of Aspidium. It is a white or yellow powder, without odor or taste, melting at 125° C., soluble in cold alcohol. Amorphous filicic acid has been recommended as an anthelmintic, and is generally considered one of the active principles of several species of Aspidium. It is usually combined with calomel and jalap. The crystalline filicic acid, also designated as filicinic acid, which is considered as an anhydride of the amorphous filicic acid, is devoid of anthelmintic action. Filmaron, C47H54O16, is an active anthelmintic constituent obtained from the ethereal extract of Aspidium. It has acid properties and occurs as a straw-colored amorphous powder, insoluble in water, difficultly soluble in ethyl and methyl alcohols and rather difficultly soluble in petroleum ether. It is readily soluble in all proportions of ether, acetic ether, amyl alcohol, chloroform, benzin, carbon disulphide, and acetone, and also, though with partial decomposition, in solutions of the alkalies MISCELLANEOUS ACTING DRUGS 399 and alkali carbonates. The alcoholic solution exhibits a slightly acid reaction. Filmaron melts at about 60° C. It exhibits a strong tendency to cake together to form a resinous mass, which is difficult to reduce to powder and dispense; hence it is not marketed in substance, but as a 10 per cent castor oil solution, which is known as " Filmaron oil." Five-tenths gram filmaron and 5 gram pumice stone, and 1 gram magnesia are finely triturated with 250 mils water, the mixture shaken for half an hour, and then filtered. On passing a rapid current of carbon dioxide through the filtrate a voluminous, flocculent precipitate forms; the filtrate should afford but very slight precipitate on the addition of hydrochloric acid. On dissolving 0.1 gram filmaron in 0.2 gram acetic ether or 0.2 gram carbon disulphide by rotation in a test-tube, and setting the stoppered tube aside for three days, no separation should have taken place at the end of this time (absence of other malefern constituents, filicic acid and flavaspidic acid). One-tenth gram filmaron should completely dissolve in 0.5 gram warm petroleum ether and leave no more than a slight trace of undissolved substance. To detect the filmaron in the castor oil solution (filmaron oil), dilute the filmaron oil with ether, shake out with sodium hydroxide solution, acidulate the alkaline liquid, and then take up the liberated filmaron with ether. On evaporating the ether and filmaron is obtained as a residue. PICROTOXIN The berries of Cocculus indicus or Anamirata paniculata (Menisper- macese), a small climbing shrub growing in India and the Malay Archi- pelago, contain a feebly acid principle, picrotoxin. Both the berries and purified picrotoxin are used medicinally in nervous disorders, where they exert a sedative action, and in phthisis to relieve night sweats. They are also employed externally to destroy parasites. Pills and hypodermic tablets of picrotoxin usually contain about A to sV grain. A decoction of the berries acts as a powerful fish poison and the fruit has received the name " fish berry." The practice of collecting fish by means of the fruit is not uncommon, and there are certain proprietary poisons which owe their efficacy to the presence of picrotoxin. The kernel contains the picrotoxin with picrotin and picrotoxinin. The shells contain alkaloidal substances to which the names menispermin and paramenispermin have been given. PICROTOXIN, C 30 H 3 4O 13 Picrotoxin, when pure, is a colorless, shiny, prismatic crystalline sub- stance, bitter, odorless, permanent in the air, and melting at 200° C. 400 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS It is sparingly soluble in cold water, but dissolves quite easily in hot aqueous solutions and in the presence of acids or alkalies. It dissolves easily in hot alcohol and benzol and less readily in chloroform and ether, and it may be removed from acid solutions by any of these immiscible solvents, but it cannot be extracted in the presence of alkalies. Treated with concentrated sulphuric acid, picrotoxin gives a yellow color, turning orange and becoming red on warming and gradually reddish- brown, while the solution becomes fluorescent, best observed by pouring the liquid into a narrow test-tube. A drop of a 20 per cent alcoholic solution of anisaldehyde added to a solution of picrotoxin in sulphuric acid produces a blue-violet ring, becoming blue. Evaporated with con- centrated nitric acid it leaves a reddish-yellow residue, which becomes red when moistened with aqueous alkali hydroxide. A solution in con- centrated sulphuric acid treated with potassium nitrate, gives a red to violet color when strong alkali hydroxide is added. A mixture of picro- toxin and sucrose becomes red on treatment with concentrated sulphuric acid. An aqueous solution of picrotoxin reduces Fehling's solution and ammoniacal silver oxide, but it gives no precipitate with neutral, or basic lead acetate, Mayer's reagent, gold, platinic, or mercuric chlorides, tannic acid, or most other general reagents for alkaloids. Picrotoxin is not a glucoside. It is decomposed by the action of hydrochloric acid into picrotin and picrotoxinin, both dilactones: C30H34O13 = C15H18O7+C15H16O6 Picrotin Picrotoxinin The reaction also occurs when a solution in chloroform is allowed to stand, or when an aqueous or benzene solution is boiled. Both of the products of decomposition reduce Fehling's solution and ammoniacal silver oxide. Picrotin melts 245-250° and picrotoxinin at 200 C. Hydrolysis with aqueous alkali first gives alpha-pier otoxininic acid, C15H18O7, and beta-picrotinic acid, C15H22O9. These yield with excess alkali the dicarboxylic acids of picrotoxinin and picrotin, C15H20O8 and C15H22O9, respectively. These bodies, with the exception of alpha- picrotoxininic acid, do not reduce Fehling's solution or ammoniacal silver oxide. Picrotoxin is speedily decomposed when boiled with alkalies. The separation of picrotoxin from medicinal preparations is not dif- ficult. In the general scheme of analysis it will be found in greatest amount in the fraction obtained by shaking an acid aqueous solution with chloroform. It may be purified by dissolving in dilute ammonia, shak- ing out neutral substances with ether and chloroform, acidulating, and extracting with chloroform. The crystalline residue is then subjected to MISCELLANEOUS ACTING DRUGS 401 the several color reactions, and a dilute aqueous solution may be added to a bowl containing a few small fish. The fish will soon begin to swim with uncertainty, lose their balance and ultimately rise to the surface, lying on their sides and frequently opening mouths and gill covers. Its estimation in pills and tablets may be accomplished by trans- ferring a sufficient quantity of the sample to a separatory funnel, dis- integrating with water, acidulating, and agitating with chloroform. Three or four extractions should be made and the combined extracts filtered into a tared beaker, evaporated, and weighed. CASPSICUM AND CAPSAICIN Capsaicin is the pungent principle of the fruit of Capsicum fastigiatum (Solanacese) , C. annuum, and other species of Capsicum, the former being by far the most pungent and furnishing the cayenne type of red pepper, to which medicinal Capsicum belongs, while the latter provides the paprika. Capsicum is administered both in the powdered form and as the oleo- resin in cases of enfeebled or languid digestion, dyspepsia, atonic gout, and colic, and externally as a rubefacient. It will be found in some liniment formulas, also in ointments and plasters and to a large extent in pills and tablets. It is also used to increase the pungency of ginger ales and a few other types of temperance beverages. Capsicum and myrrh are dispensed together in liquid form, and com- pound tincture of opium and chlorodyne formulas contain Capsicum. Among the great number of different pill and tablet combinations the following types may be mentioned, all of which often contain Capsicum; aloin, belladonna, strychnin, and Podophyllum resin; belladonna, Hyos- cyamus, Nux Vomica and Podophyllum resin; aloin, Nux Vomica, Podo- phyllum resin, colocynth comp. and croton oil; aloin, jalap resin, Podo- phyllum resin ; strychnin and Hyoscyamus ; aloes, gamboge, Podophyllum resin, and croton oil; aloin, jalap, and Podophyllum resin; gamboge, leptandra, Hyoscyamus, and oil of peppermint; belladonna, Nux Vomica, Cascara sagrada, Euonymus and Xanthoxylon; Podophyllum resin, Tar- axacum, Euonymus, Eupatorium, and Apocynum; Podophyllum resin, Hyoscyamus, Nux Vomica and mercury mass; the above formulas being of the cathartic type. Mixtures intended as fiver regulators will contain jalap and Podo- phyllum resins, Hyoscyamus and colocynth comp.; aloes, rhubarb, Podo- phyllum resin, and Hyoscyamus; Podophyllum resin, Nux Vomica, Leptandra, and Iris versicolor; jalap, and Podophyllum resin, Leptandra and gamboge; aloes, jalap, gamboge, Leptandra, Veratrum viride, croton oil, and calomel, sometimes with addition of Podophyllum and butter- nut. Stomachics and anti-dyspeptic tablets and pills will contain rhu- 402 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS barb, Cinchona and Ignatia; rhubarb, strychnin, and ipecac; pepsin, Nux Vomica, and ipecac; pepsin, Nux Vomica, and charcoal; rhubarb, strychnin, ipecac, gentian, and sodium bicarbonate; gentian, mercury mass, ipecac, and strychnin; ginger, sodium salicylate, and cardamom; strychnin, ipecac, pepper, and gentian. Compounds intended for the relief of diarrhea and summer cholera consist of rhubarb, opium, camphor, and oil of peppermint; calomel, ipecac, morphin, and camphor; morphin, Cannabis sativa, nitroglycerin, Hyoscyamus, and oil of peppermint. Compounds for ague contain Gelsemium, Xanthoxylon, and cinchonidin; Nux Vomica, Hyoscyamus, and quinin; arsenous acid, cinchona alkaloids, eucalyptus, and iron ferrocyanide. Antiperiodic pills contain cinchonidin, ferrous sulphate, Podophyllum resin, strychnin, and Gelsemium. Cold tablets consist of quinin, aloin, calomel, aconite, ipecac, and opium; quinin, aloin, sodium bromide, acetanilid, and Cascara sagrada; and a formula for dipsomania contains quinin, arsenous acid, strychnin, and zinc oxide. The Capsicum species were originally confined to the American tropics, but they are now cultivated in all parts of the world. The characteristic constituent is a pungent substance, capsaicin, which is present to the amount of about .15 per cent. The drug also contains a small quantity of a non-pungent alkaloidal substance. Considerable oily material can be extracted by volatile solvents, and oleoresin of capsi- cum, which contains practically all of the capsaicin, is a well-known pharmaceutical product and is the form in which the drug is usually administered. Capsaicin crystallizes in pearly white leaflets melting 64 to 54.5°, but as ordinarily extracted in analytical work it is a colorless amorphous residue, often in such small quantity as to be invisible. It is intensely pungent, dilutions of one part in a million in water imparting perceptible warmth to the tongue and lips. It is soluble in the ordinary organic solvents and slightly in water, and is removed from aqueous mixtures by petroleum ether, hence in conducting analysis with the procedure of immiscible solvents, capsaicin is one of the first of the common substances encountered. Capsaicin has the probable composition, C18H27NO3, but it is not an alkaloid. It apparently contains a phenolic hydroxl and a methoxy group. Its alcoholic solution when treated with dilute ferric chloride, develops an evanescent greenish-blue color. An alcoholic solution acidu- lated with hydrochloric acid, and treated with a little platinic chloride develops an odor like vanilla when allowed to evaporate spontaneously. A solution of capsaicin in concentrated sulphuric acid develops a violet color on adding sugar. Nelson 1 has shown that it is a condensation 1 J. Am. Chem. Soc, 1919, 41, 1115. MISCELLANEOUS ACTING DRUGS 403 product of vanillyl amine (3-hychoxy-4-methoxybenzylaniine) and a decylenic acid: OCH3 H0/~ NCH2NHCOC9H17 The color, and odor reactions above described are of no value for detect- ing capsaicin in the ordinary run of medicinal preparations and beverages because of the comparatively small amount that is present in the quantity of the sample which can be sacrificed for analytical work. The only satisfactory method of detection is one based on its physiological action, and this must be conducted in such a way as to exclude the possibility of confusion with piperin and ginger principles. Lawall describes a method for detecting capsaicin which excludes the possibility of ginger bodies being present. If the sample contains alcohol add sufficient sodium hydroxide to render it slightly alkaline and then evaporate until the alcohol is expelled. Transfer the residue to a separatory funnel with water, acidify with sul- phuric acid and shake out with ether. Separate and evaporate the ether, add alcoholic potash to the residue, and heat for half an hour in a boiling water-bath under a reflux. Evaporate to dryness, take up the residue in water, and extract with ether. Separate ether extract and wash with water until the washings are neutral to litmus. Then allow ether to evapo- rate spontaneously in a dish. The tip of the tongue is then applied to the residue or to the center of the bottom of the dish where a residue would naturally concentrate when the presence of capsaicin will be apparent by its characteristic burning sensation. If but a minute amount is present it may take a few minutes for the reaction to develop, and in some cases it may be necessary to apply the entire residue to the tongue. Piperin, the alkaloid of pepper winch would appear in the same frac- tion as . capsaicin, is readily distinguished by means of its characteristic color tests. The comparative pungency of capsicum is determinable by physi- ological means. By True's method 1 a small weighed quantity of the powder is placed in a mortar with a small weighed quantity of cane sugar and triturated until the powders are completely mixed and reduced to great fineness. If on tasting a small portion of the powder, the sensa- tion of pungency is noted, further weighed quantities of sugar are added until the pungency can no longer be perceived. A ratio is thus established between the original weight of the capsicum used and the weight of the sugar necessary to bring the sensation of pungency just to the point of disappearance. 1 Bulletin U. S. Dept. Agri. No. 43, Bu. Plant Industry. Dec. 16, 1913. 404 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Scoville * proposes an analogous procedure, using an alcoholic extract of the drug. One gram of the powdered sample is macerated overnight with 100 mils of alcohol and after thorough shaking is filtered. The alcoholic solution is then added to sweetened water in definite proportions until a distinct but weak pungency is perceptible on the tongue. Pow- dered capsicums may run from 1-20,000 to 1-100,000, and oleoresin may test 1-150,000 and upwards. GINGER, Zinziber officinale (Scitaminese) possesses a pungent rhizome employed in dyspepsia, flatulent colic, and enfeebled conditions of the alimentary canal. It is an agreeable addition to bitter infusions and tonic mixtures, and is used to a large extent in remedies for diarrhea, dysentery, cholera morbus, colic, nausea, etc. Extract and tincture of ginger are popular household remedies. The oleoresin prepared similarly to the oleoresin of capsicum enters into the composition of pill and tablet formulas and is also used in the preparation of extracts for ginger ale. The powdered rhizome is combined with pancreatin, pepsin, and other digestives, and bismuth subcarbonate in popular remedies for impaired digestion which are sold in powder form. The pill and tablet formulas containing ginger are of the following type: aloes, ferrous sulphate, and Conium; aloin, Cascara sagrada, bella- donna, strychnin, and Podophyllum; Colocynth, jalap, gamboge, rhubarb, and calomel; cinchonidin, cardamom, gentian, pimento, pepsin, and hydrochloric acid; pepsin, pancreatin, and Nux Vomica; pepsin, pan- creatin, bismuth subnitrate, Nux Vomica, and sodium bicarbonate; sodium salicylate, Capsicum, and cardamom; aloes, ferrous sulphate, black hellebore, myrrh, soap, and canella (female pills); pepsin, char- coal, and magnesia (dyspepsia lozenges). Aromatic tincture N.F. contains ginger, cinnamon, cloves, cardamom, and galangal root. Ginger is obtained chiefly from India, the West Indies and certain parts of Africa. The Indian variety is known as black ginger and is prepared by scalding the cleansed root in boiling water and rapidly dry- ing it. In Jamaica the best roots are deprived of their epidermis and dried carefully in the sun, this variety being known as white ginger. The Indian variety is sometimes found coated with calcium carbonate or sul- phate, and again artificially bleached to simulate the white ginger from Jamaica. Ginger contains from 2.5 to 7 per cent of resinous material and fixed oil. Its flavor and characteristic odor depends on a volatile oil, and its 1 J. Am. Pharm. Ass., 1, 453. MISCELLANEOUS ACTING DRUGS 405 pungency on the resinous constituents. The pungent principle has been isolated and is, like capsaicin, a derivative of vanillin, having the follow- ing composition: OCH3 HO< >CH 2 CH 2 COCH3 It is called Zinzerone by its discoverer, Nomura. Kraemer and Sindall * obtained the accompanying analytical data with authentic commercial samples of ginger from different sources: Total Ash Ash insol. in 10 per cent HCI Cold H 2 extract Volatile Ether Extract N on- vol. Ether Extract Alcoholic Extract Crude fiber Starch CaO African . . 5.74 1.15 12.62 7.17 8.49 7.20 2.62 55.07 0.12 Calcutta . 7.47 2.02 14.20 3.06 6.50 6.40 5.46 47.89 0.13 Calicut . . 5.64 0.55 13,08 4.62 6.42 7.76 1.64 48.77 0.33 Cochin . . . 6.43 0.85 14.30 7.03 6.68 8.04 3.06 52.00 0.58 Jamaica. . 3.88 0.45 15.54 3.23 7.30 5.80 1.44 58.97 0.17 Japan . . . 6.16 0.69 14.40 7.39 7.01 10.48 1.60 55.97 1.68 Kebler and Kimberly 2 found that Calcutta and Japanese gingers are not suitable for the preparation of the U. S. P. tincture, and that a properly prepared tincture should contain not less than 90 per cent -alcohol and from 1.25 to 1.75 per cent non-volatile matter. The presence of ginger in medicinal preparations is usually noticed by the aromatic vapors evolved on evaporating an alcoholic extract of the sample, and by the characteristic pungency of an aqueous decoction of the evaporated residue left by the alcohol. The absence of capsaicin may be determined by the procedure given under capsicum. In certain doubtful cases the actual identity of ginger may be desir- able. Seeker has suggested a method for accomplishing this: Dilute 10 mils of the extract to 30 mils, evaporate off 20 mils, decant into a separator and extract with an equal volume of ether. Evaporate the ether spontaneously in a porcelain dish and to the residue add 5 mils of 75 per cent sulphuric acid and about 5 mg. of vanillin. Allow to stand for fifteen minutes and add an equal volume of water; when in the pres- ence of ginger extract an azure-blue color develops. The actual value of this method is probably overestimated because it appears from recent work that certain hydrocarbon-like constituents of volatile oils will produce a similar if not an identical shade of color when subjected to the same procedure. Hence it would be advisable 1 Am. J. Pharm., 80, 303. 2 U. S. Dept. Agri. Bu. Chem. Bull., 152, 244. 406 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS to consider with great caution any positive evidence as to the presence of ginger when based on this test alone. ASARUM CANADENSE. CANADA SNAKE-ROOT Asarum canadense (Aristolochiacese) , wild ginger, or Canada snake- root, possesses a pungent root stock. It is used medicinally as an aro- matic, stimulant, carminative, and diaphoretic. It is prescribed with Cinchona for certain forms of low fever. It is also combined with ipecac in syrupy mixtures. A. acuminatum and A. reflexum are eastern plants resembling the above species, and their roots might be mistaken for Canada snake-root by an inexperienced collector. Power examined the rhizome and found a volatile oil, resin, fat, an amorphous yellow coloring matter, uncrystallizable sugar, and a small quantity of a feebly basic principle. The volatile oil contained pinene, an isomer of borneol, asarol, which is perhaps identical with linalool, asarin a neutral substance, coeruline, and acetic and valeric esters of linalool. SERPENTARIA. VIRGINIA SNAKE-ROOT The rhizomes of both Aristolochia serpentaria and A. reticulata (Aris- tolochiacese) are official in the U. S. Pharmacopoeia as Serpentaria. As a drug it has stimulant, tonic, diaphoretic, and diuretic properties, and is often used in low fevers either by itself or combined with Cinchona alkaloids. It is also used in dyspepsia and as a gargle for sore throat. The extract has been at various times recommended as an emmenagogue and as a cure for snake bite. Virginia serpentaria, also known as serpentary, is found in rich dry woodlands from Connecticut to Michigan and southward. Texas ser- pentaria (A. reticulata) occurs in the Southwestern States, growing along river banks from Arkansas to Louisiana. The crude drug will often be found mixed with other root drugs, including Spigelia, senega, and abscess root (Polemonium reptens), the latter resembling serpentaria closely except that it is nearly white. Many other species of the genus Aristolochia of this countrv and of foreign habitat are used as drugs. The characteristic constituents of the rhizome appear to c a bitter principle and volatile oil containing pinene, and esters o which give the drug its camphoraceous odor and flavor. Ar has been reported from a species of Aristolochia from South but no basic substance has been isolated from the plant growi in the United States. MISCELLANEOUS ACTING DRUGS 407 GLYCYRRHIZINIC ACID AND LICORICE ROOT Licorice root from Glycyrrhiza glabra and G. glandulifera (Fabacese) possesses a sweet principle which is employed for the purpose of masking the taste of other drugs, and the extract will be found in a great variety of medicinal compounds. As a drug, licorice is useful as an emollient and demulcent in coughs, catarrh, irritations of the bronchial and urinary organs, and other similar affections of the mucous surface. It will be found in fluid extract aloes compound; with aloes and myrrh; in black cohosh compound; rhubarb compound, various sarsaparilla compounds; in compound quinin elixirs, with glyceroles of eriodictyon, heroin, etc., elixirs of Cascara sagrada and Berberis aquifolium; Tar- axacum and wild cherry; eucalyptus, gentian; and many other bitter tonic compounds and bitter cough remedies. Aromatic elixir of glycyr- rhiza and syrup of glycyrrhiza are national formulary preparations. Compound licorice powder consists of powdered licorice root, senna, washed sulphur, sugar, and oil of fennel. Tully's powder consists of powdered licorice root, morphin sulphate, camphor, and calcium car- bonate. Brown mixture consists of extract of licorice, powdered opium benzoic acid, tartar emetic, camphor, and oil of anise. Among the tablet and lozenge formulas in which extract of Glycyr- rhiza functionates as a demulcent or emollient may be mentioned ammo- nium chloride and cubeb with and without codein; Conium and cubeb; benzoic acid, cubeb, and belladonna; ammonium chloride, tolu, cubeb, senega, ipecac, and Hyoscyamus; ammonium chloride, cubeb, and cocain; Krameria, bismuth subnitrate, and opium; cubeb, tolu, and Sassafras; coltsfoot, cubeb, peppermint, tolu, Capsicum, and oil of anise; pine tar, eriodictyon, senega, and wild cherry; and coltsfoot, acacia, horehound, wild cherry, tolu, anise, cubeb, and Capsicum. The commercial extract of glycyrrhiza or licorice paste is prepared by water extraction. It is a hard black mass, brittle, breaking with a shining fracture and almost entirely soluble in boiling water. Gums and resinous constituents are usually present and some varieties contain commercial glucose or corn syrup. This form is used almost entirely in the manufacture of chewing tobacco. The fluid and solid extracts of the Pharmacopoeia are prepared with ammonia and alcohol. Ammoniated glycyrrhizin is a scaly preparation of the sweet principle in the form of its ammonium salt. The important constituent of the root and extract is glycyrrhizic acid or gly^yrrjnzim^^It occurs in the root in soluble form, and by treat- ing the extract with a mineral acid the compound is broken up and the crude acid is precipitated as a brown resinous mass, difficultly soluble in water and especially when acidulated. When pure it forms colorless 408 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS crystals, melting 195°. Chemically it is a diglucuronic ether of glycyr- rhetic acid and by Tschirch is accorded the structural formula: I I /OHC • CHOH— CHOH— CHO • CHOH • COOH C 3 iH450 3 ^-COOH \OHC ■ CHOH— CHOH— CHO— CHOH • COOH I I Housemann 1 reports that glycyrrhizinic acid contains nitrogen. In his investigation he evaporated a solution of the acid to dryness in vacuo, crystallized the residue twice from hot glacial acetic acid, and finally dried over potassium hydroxide in vacuo. Analysis of the product showed 58.37 per cent carbon, 7.72 per cent hydrogen, 1.09 per cent nitrogen. Three recrystallizations from glacial acetic acid raised the nitrogen to 1.89 per cent. The substance turned brown at 185° and partly melted with frothing at 203-205°. It was readily soluble in hot water, the solu- tion gelatinizing on cooling. Housemann found 2 per cent of sucrose in the root. The inner bark of both green and dried root, but not the outer bark or central part of the root, contain hemolytically active saponins, in addition to the saponi- genin glycyrrhetic acid. These are extracted by 75 per cent alcohol but not by water or by alcohol weaker than 50 per cent. Properly purified glycyrrhizin at a dilution of 1-20,000 has a lasting pure sweet taste. In the analysis of medicinal products, glycyrrhizinic acid will appear when an evaporated alcoholic extract of the sample has been treated with water, filtered from any resinous constituents, and then treated with dilute sulphuric acid previous to shaking out with immiscible solvents. The appearance of a brown, resinous precipitate at this point is strongly indicative of glycyrrhizinic acid. It usually sticks to the side of the con- tainer and the liquid is readily decanted, the substance washed with ice water, or very dilute acid and then dissolved in ammonia and the filtered solution evaporated. The residue, which will have a scaly appearance, is soluble in water and the solution has a characteristic sweet taste. Housemann 2 recommends the following procedure for the analysis of licorice paste: Moisture and ash are determined in the usual manner. Matters Insoluble in Cold Water. — Two grams of the extract are spread on the sides of a small, copper gauze basket, which is placed in a 100-mil cylindrical glass tube drawn out to a conical end and contain- ing about 75 mils of distilled water. The tube is closed with a rubber stopper and agitated in a shaking machine until the paste is completely 1 Amer. J. Pharm., 1916, 88, 97. 2 Amer. J. Pharm., 84, 1912, 531. MISCELLANEOUS ACTING DRUGS 409 disintegrated (one-half hour to one hour) and then whirled in a Babcock centrifuge for fifteen minutes at 1000 revolutions per minute. The clear liquor is poured off and the sediment stirred up with fresh water and whirled for a further fifteen minutes. After pouring off the liquor, the sediment is washed into a tared glass dish, evaporated and weighed. Most licorice pastes, when freshly made, will contain not more than 3 per cent by weight of matters insoluble in cold water, unless made from very starchy root or from liquor which, having been partly chilled, con- tains gelatinized starch. A paste containing more than this amount should be dissolved without the aid of a shaking machine by suspending in cold water, as the use of the shaking machine is found to give low results with pastes containing much insoluble matter. Many experiments have shown that fifteen minutes is a sufficient time to centrifuge at 1000 revo- lutions, the results being identical with those obtained by twenty-four hours settling in a tall jar. Matters Insoluble in Hot Water. — This estimation is carried out in a similar manner to the preceding determination, using hot water. Starch and Gums. — Two grams of licorice mass are dissolved in 10 mils hot water, in a centrifuge tube similar to that used for " matters insol- uble in cold water." The solution is cooled and 20 mils 80 per cent alco- hol (by volume) are added with stirring. Fifty mils 95 per cent alcohol are then added gradually with stirring. After allowing to stand two hours, which time is found sufficient to precipitate all starch and gummy matters, the contents of the tube are centrifuged. After pouring off the clear liquor, the precipitate is stirred up with 80 per cent alcohol and centrifuged. This operation is carried out three times in all. The pre- cipitate, consisting of starch and gums, and the mechanical impurity in the paste, is washed into a tared dish, evaporated, and weighed. The mechanical impurities (matters insoluble in hot water) are deducted, to give the true weight of starch and gums. Glycyrrhizin. — The clear 80 per cent alcoholic liquor, poured off from the starch and gums, is evaporated just to dryness in vacuo on a water- bath. The residue is transferred to a small conical beaker with 30 mils water and after cooling to 15° C, the crude glycyrrhizin is precipitated with 3 mils dilute sulphuric acid (10 mils cone, sulphuric acid to 300 mils water). After standing for two hours (twelve to twenty-four hours, as usually recommended, is unnecessary and gives lower results) at a tem- perature of about 10° C, the contents of the beaker are cooled in ice for half an hour, and the clear supernatant liquor poured through a small filter. The glycyrrhizin is washed four times by decantation with ice water, in which it is practically insoluble. The glycyrrhizin in the beaker, together with any that may have beeen transferred to the paper, is dis- solved in dilute alcohol. Two drops of 5 per cent ammonia are added 410 GLUCOSIDES GLUCOSIDAL DRUGS AND NATURAL DRUGS to neutralize traces of sulphuric acid, and the solution is transferred to a tared dish, evaporated, and the crude glycyrrhizin weighed. Sugars. — The filtrate and washings from the glycyrrhizin, amount- ing to about 70 mils, are received in a 100-mil graduated flask. Enough of a concentrated solution of basic lead acetate is added to precipitate both the sulphuric acid and the resins, bitter substances, coloring matters, etc. (3 mils are usually sufficient). The liquid is made up to 100 mils and an aliquot filtered into a 100-mil graduated cylinder. The excess of lead is exactly removed with sodium carbonate, the liquid made up to 100 mils again, filtered, and titrated with Fehling's solution before and after inversion. The method for the determination of glycyrrhizin can be used to advantage in estimating that substance in commercial ammonium glycyr- COMPOUND LICORICE POWDER The moisture and ash can be estimated by the ordinary methods. Glycyrrhizin, sugar, and water-soluble extract are determined by digest- ing 5 grams of the sample with 250 mils of water for twenty-four hours with occasional agitation. After settling, aliquots of 50 mils each are used for the water soluble extract and sugar determinations, and 100 mils for the glycyrrhizin. The technique to be employed in estimating glycyr- rhizin is the same as in licorice paste. The total sulphur is determined by oxidizing 1 gram of the powder with fuming nitric acid and a little potassium nitrate or chlorate, and finally precipitating with barium chloride. The anthraquinone derivatives of the senna can be estimated by the method described on page 62. Parkes and Major 1 who outlined a procedure essentially like this one examined 13 samples of compound licorice powder and obtained the following data: moisture 3-7.9 per cent; ash 4.6-6.2 per cent; water extract 61.1-63.9 per cent; sucrose 48.3-50.3 per cent; glycyrrhizin 1.2-2.9 per cent; total sulphur 7.8-9.2 per cent. Tschirch and Gauchmann report the presence of glycyrrhizinic acid in the root of Periandra dulcis and the bark of Pradosia lactescens, both from Brazil. Eupatorium rebaudianum contains two sweet principles of the nature of glucosides. They have been separated by dissolving in methyl alcohol and pouring into absolute alcohol, which precipitates rebaudin and leaves eupatorin in solution. The former is soluble in water, methyl alcohol, and dilute acids, but insoluble in ethyl alcohol and ether. The latter is soluble in water, methyl and ethyl alcohols, and acids, but insoluble in ether. They are therefore essentially different from glycyrrhizinic acid. 1 Analyst, 1914, 39, 160. MISCELLANEOUS ACTING DRUGS 411 This eupatorin must not be confused with the substance of the same name which has been extracted from Eupatorium perfoliatum or common boneset. CANTHARTDES AND CANTHARIDIN Cantharidin occurs in the anatomy of a number of insects. The species Cantharis versicatoria is official in our Pharmacopoeia. If kept • perfectly dry the activity is retained for a long time, but it is subject to the attack of a small worm which consumes the interior parts, and the vesicating power is lessened to a considerable degree by the attack of this pest. Some of the other species of insects containing cantharidin include Mylabris oculata, Thunb; M. holocericia, Kley; Decatonia lunata, Pallas; Electica wahlborgia, Fabr; Cantharis vellata; Lytta ccelestina; Cantharis vittata; C. cimeria; C. marginata; C. atrata; C. vulnerata and others. Cantharides as a drug is used principally in remedies for the stimu- lation of the urinary and genital organs, in hair tonics, and locally for blistering purposes. It is reported to be of value in producing sexual excitement. It is often combined with phosphorus, Nux Vomica, damiana, and zinc phosphide; with belladonna, saw palmetto, and corn-silk; and with guaiac, aloes, and ferrous sulphate. Cantharidal collodion is a pharmacopceial preparation of this drug which furnishes a ready medium for the exhibition of its vesicating properties. Cantharidin occurs partly free and partly combined and the nature of the combination is unknown. It is volatile on evaporation with sol- vents, but can be dried at 60° for two hours without loss. It is fairly soluble in acetone, chloroform, and ethyl acetate, moderately in alcohol, ether, and hot water, but only very slightly in cold water and petroleum ether. Cantharidin forms colorless, shining, neutral, rhombic leaflets, melt- ing 218°, and subliming at higher temperatures in white needles. It is a monobasic acid and a /5-lactone. Potassium or sodium hydroxide break the labile /3-lactone ring, and by this means cantharidin forms the alkali salt of dibasic cantharidic acid. H H /?\/ CHC00H /?\ /CH 2 -COOK H 2 C C— O H 2 C + 2KOH = CH CH 2 ] \l H 2 C C— C=0 H 2 C C— COOK \c/ \c/ H 2 H 2 0H +H 2 412 GLYCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS These alkaline salts are crystalline and on treatment with a mineral acid cantharidinic acid is set free, which soon loses a molecule of water and passes into cantharidin. The alkali cantharidinates are used medi- cinally as remedies for phthisis. In the general scheme of qualitative analysis of medicinal preparations cantharidin will, in part, be found in the aqueous solutions of the evapo- rated alcoholic extract of the mixture from which it will be separated in the ether fraction. As it gives no characteristic color resctions and as it is in such small quantity usually that a melting-point determination is impossible, it is necessary to resort to a physiological reaction which depends on its vesicatory power. For this purpose the residue is dissolved in chloroform and the solution applied drop by drop to the under side of the forearm above the wrist. As each drop evaporates another is applied in the same spot. If any cantharidin is present the tingling effect will soon be apparent and the blister will appear. Assay of Cantharides. — Twenty grams of cantharides, in fine powder, are moistened with 3 mils of strong hydrochloric acid, and extracted, in a Soxhlet apparatus, with 80 mils of benzene for two hours. The residue is washed with 25 mils of benzene, and the benzene removed from the extract by distillation and, finally, by a current of air. The distilled benzene is shaken with successive portions of 20 mils, 20 mils, and 10 mils of a 1 per cent solution of potassium hydroxide to recover any traces of cantharidin which have distilled over, and the mixed alkaline solu- tion is acidulated with hydrochloric acid, made up to 105 mils with dis- tilled water, and added to the residue of fat and cantharidin left after distilling off the benzene. The mixture is boiled for ten minutes under a reflux condenser, and so soon as the layer of fat has separated, 100 mils of the hot aqueous layer are pipetted off. The boiling is then repeated four times for five minutes after addition each time of 50 mils of distilled water, 50 mils of the separated aqueous layer being removed after each boiling. The mixed aqueous solution is acidified with 3 mils of strong hydrochloric acid, and shaken with successive portions of 30, 30, 20, and 20 mils of chloroform. The chloroform extract is distilled in a tared flask, the residue washed with quantities of 5, 5, and 2 mils of a mixture of equal parts of absolute alcohol and petroleum spirits saturated with cantharidin, and the cantharidin dried at 60-65° C. until of constant weight. DETERMINATION OF CANTHARIDIN IN TINCTURE, OIL AND PLASTER OF CANTHARIDES Tincture. — Fifty grams of the tincture, 25 grams of water, and 1 mil of sodium carbonate solution (1:2) are evaporated tog-ether to dryness MISCELLANEOUS ACTING DRUGS 413 on the water-bath. The residue is taken up with 10 mils of water, treated with 2 mils of hydrochloric acid (1:4), and shaken out with 10 mils of chloroform, which has been used previously to rinse out the flask. After separation, the chloroform is drawn off, and the acid aqueous liquid is again shaken out with 5, 5, and 5 mils of chloroform in succession. The chloroform extract is evaporated at a gentle heat, the last traces of sol- vent being blown off with an air current. After standing for twelve hours, the air-dried residue is treated once with 10 mils, then four times successively with 5 mils of light petroleum spirits. These petroleum spirit washings are passed through a small filter. The air-dried residue and this filter are then washed, first with 10 mils of water containing a drop of ammonium carbonate solution, then with pure water, and dried at 50° C. The dry residue is dissolved in a little acetone, and passed through the dry filter, into a small tared flask. The solvent is evapo- rated off at a gentle heat by the aid of a current of air, and the brownish- yellow residue is dried, first at 50° C. and finally in the water oven, till of a constant weight. CHAPTER XIII BOTANICAL DRUGS WHITE PINE The inner bark of the white pine, Pinus strobus (Pinacese), is used as an expectorant and is one of the ingredients of white-pine syrup. The extract of the drug is usually combined with several of the following: wild cherry, balsam poplar buds, spikenard, Sanguinaria, sassafras, squill, senega, ipecac, opium, camphor, morphin, chloroform, methyl salicylate, potassium nitrate, glycerin, codein, Cannabis sativa, Eriodictyon, ammo- nium chloride, tar, tolu, and honey. Compound syrup of white-pine contains white-pine, wild cherry bark, balsam poplar buds, spikenard, Sanguinaria, sassafras, morphin, and chloroform. Coniferin, Ci 6 H 2 20 8 -l2H 2 Coniferin occurs in the cambium sap of coniferous trees. It forms white satiny needles with two molecules of water of crystallization, efflores- cing in dry air and becoming anhydrous at 100°, melting at 185°. It is soluble in alcohol and slightly in hot water, insoluble in cold water and ether. The aqueous solution has a bitter taste and is laevorotatory (= —35.6°, in chloroform, myricyl alcohol, heptacosane, C27H56, ipuranol and a mixture of lauric, palmitic, stearic, cerotic, oleic, and linolic acids. IRIS FLORENTINA The root of I. florentina, the white flag or orris, was formerly employed as a cathartic and emetic, but at present finds its chief use in dentifrices, bath, toilet, and hair powders. It has a limited use in surgical work because of its great absorptive power. Orris root contains a large percentage of starch and 0.1-0.2 per cent of volatile oil, which consists chiefly of myristic acid, with a ketone to which the name irone (ionone?) has been given, and to which the odor of the root is due. The odor of the pure ketone is pungent, and in the concentrated form seems to differ entirely from that of the violet, but the violet aroma becomes apparent when irone is dissolved in a large amount of alcohol and the solution evaporated. CROCUS SATIVUS. SAFFRON Crocus sativus (Iridacese) furnishes a drug closely allied to those just mentioned. It was formerly used as an antispasmodic and narcotic 1 Amer. J. Pharm., 1911, 83, 1. BOTANICAL DRUGS 417 emmenagogue, but is now mainly a coloring and flavoring agent. It is still a component of pills containing aloes, myrrh, rue, and savine; of Warburg's Tincture; and of some Cinchona preparations. Its high price has made it an attractive subject for adulteration, and though its importance as a drug is slight, much attention has been devoted to suppressing the traffic in the adulterated product. The plant is perennial, rising from a conn, the flowers being lilac- purple with orange-red stigmas, which furnish the article known commer- cially as saffron. It should not contain the yellow styles. Dried saffron has about 7.5 per cent ash. When chewed it imparts an orange-red color to the saliva. It contains a volatile oil. To water it yields, among others, a yellow substance to which the name crocin has been given. The yellow sub- stance is also soluble in dilute alcohol, but only slightly in absolute alcohol. The adulterants include the florets of species of composite, Calendula, Carthamus, and Arnica, fixed oils, glycerin, mineral matter, exhausted saffron dyed with coal-tar colors, and factitious products of which " Fem- inella " is a type, and consisting of florets of Calendula or other flowers colored to imitate the characteristic shade of saffron. Vicari 1 recommends the use of sulphomolybdate reagent (60 mils cone, sulphuric acid and 40 mils 10 per cent sodium phosphomolybdate) for detecting Carthamus in saffron. The powder is spread over a glass slide in a thin coating without lumps. A drop of the reagent is allowed to fall upon the powder and well mixed with it. A greenish-blue color soon develops and then a cover glass is gently pressed down on the slide. Under a microscope of 50 diam. magnification, the particles of Carthamus are detected by their reddish color in the midst of the blue particles of saffron. If the particles of saffron are somewhat voluminous, or if the preparation of the powder for the microscope is not properly done, the coloration may be masked. An indication of the presence of Carthamus is furnished by observation under the microscope (100 diameters magni- fication) of the pollen grains. These are composed of two membranes, the outer being hard, resistant, and granulated exteriorly, the inner soft and delicate, and filled with a relatively dense, hyaline, protoplasmic liquid. The outer membrane is pierced with three symmetrically arranged openings, through which the inner issues, forming three typical protuber- ances. Under the microscope and in the presence of the reagent the outer membrane becomes colored brown, while the protuberances gradually elongate, turn a bright greenish blue, and finally take on sac-like forma- tions, on account of the endosmosis of the reagent through the membrane increasing the tension of the internal protoplasmic substance. In time the reagent attacks the outer membrane, exposing to view its structure, 1 Mitt. Lebens. Hyg., 1915, 6, 195. 418 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS thickness, and granulation. Sometimes the complete inner membrane will break intact through the weakened outer. The pollen grains of saf- fron under the action of the reagent merely turn blue, without modifica- tion or swelling. MATICO The constituents of matico reported by recent investigations as occur- ring in the drug differ considerably from those which were reported when it first came into use as a medicine. This may be due to the fact that different species figure in the investigations, or that changed con- ditions of climate, environment, or source have altered the characteristic components. The official drug is supposed to be the leaf of Piper angustifoHum (Piperacese) , and according to Thorns it is hard to find this leaf in a pure, unadulterated condition. Some consignments often consist of P. lineatum either in whole or in part, and these are sometimes admixed with unidenti- fied leaves. Dr. Rusby states that the plant producing matico is a native of the Andes of Peru and Bolivia; the so-called matico plants of Mexico, Brazil, and other sections are different species. At one time all of the shipments of matico offered for import were of P. mandonii, and had a much weaker odor and taste than the genuine. In tropical America the term " matico " is applied to a number of astringent and hemostatic leaves, several of which are from species of Piper, and of importance in commerce. These include P. aduncum, P. camphoriferum, P. angustifoHum var ossanum, P. acutifolium subver- bascifohum, P. mollicomum, and P. asperifolium. In looking up the history of this drug an interesting story is found to be connected with it, though it must be taken with reserve, as it has been applied to other vulneraries of tropical America. According to the legend the name " Matico " was first applied by the inhabitants of Quito to Eupatorium glutinosum, the properties of which were discovered by a soldier called Mateo, better known under the name of Matico (little Mat- thew), who, wounded in action, applied the leaves with good effect in stopping bleeding. Another plant, Waltheria glomerata, possessing similar properties, has obtained the name Matico in the Panama region, where it is also knowm as Pado-del-soldado (Soldier's tree), and a story similar to that given above is connected with it. It is interesting to note that E. glutinosum sometimes occurs in ship- ments of matico and is now considered an adulterant. Matico occurs in remedies for diseases of the genito-urinary organs, and is usually administered in the form of an oleoresin, combined with copaiba, cubeb, and santalwood oil. It is also used to treat bronchial BOTANICAL DRUGS 419 affections, chronic diarrhea, and hemorrhage of the lungs, kidneys, and gastro-intestinal tract. Its extract is found in elixirs with Hydrangea and Uva Ursi. Maticos at one time yielded an oil which contained a product to which the name " Matico camphor " was given. This product does not appear in the distillates from any of the maticos at present on the market. Schim- mel finds that there are marked differences in the products of distillation from different lots of matico, even though there may be little difference in the odor and appearance of the drug. Scnimmel never finds matico camphor, but does get asarone and often methyl eugenol. Thorns reports the following characteristics of oils from different species of Piper which have been found in matico shipments: Oil from P. angustifolium of undoubted origin contained parsley apiol, dill apiol, a hydrocarbon boiling 121-130° under 13 mm., and a small amount of a phenol ether. Neither matico camphor nor asarone were found. Dill apiol is l-allyl-5-6-dimethoxy-3-4-methylene dioxy-benzene. Oil from P. camphoriferum (DeCandolle) has specific gravity .9500, (a) D =+19° 21' and contained camphor, borneol, terpenes and sesquiter- penes. Oil from P. lineatum had specific gravity .958, rotation +8° 45', and contained a large quantity of sesquiterpene but no camphor. Oil from a variety styled P. angustifolium var. ossanum yielded a camphor mixture. The properties reported for matico camphor by Kugler in 1885 showed it to have a melting-point of 94° C. and devoid of odor and taste. The impure substance possessed the characteristic odor of the drug and melted 89-103°. Matico camphor floats on water with a rotatory motion. It is soluble in alcohol, ether, chloroform, and benzol, and is not attacked by alkalies. With sulphuric acid it gives a yellow color, changing to red and violet; with a mixture of sulphuric and nitric acids it gives a yellow changing to violet and blue. Hydrochloric acid produces a violet color, changing to blue and green, the compound yielding brown crystals with ether, which have an ethereal odor and show a green fluorescence. Besides the volatile oil the matico leaf contains tannin, resinous con- stituents, and an acid which has been called artanthic acid, CUBEB The fruit of the cubeb contains substances of reputed value for the relief of diseased mucous membranes, and preparations containing the extract or the oleoresin are widely used for gonorrhea, gleet, and catarrhal inflammation of the urinary and other mucous tracts. The drug con- sists of the full-grown unripe fruits of Piper cubeba (Piperacese). 420 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The oleoresin, which is an evaporated ethereal extract of the drug, is combined with copaiba alone and with other substances such as santal- wood oil, turpentine, oleoresin matico, extract of buchu, extract of Krameria, iron chloride, salol, and pepsin; salol, pepsin, santalwood oil, and olive oil. Oil of cubeb is sometimes substituted for the oleoresin, and in pills and tablets we find copaiba and cubeb combined with guaiac and ferric citrate; turpentine and ferrous sulphate; santalwood oil, etc. Cubeb, either in the oleoresin, extract or powdered form, is also com- bined in pills and tablets with ferrous sulphate and Krameria; with lico- rice and ammonium chloride, sometimes with codein; with licorice and Conium maculatum; with licorice, ammonium chloride, tolu, ipecac, senega, and Hyoscyamus; with licorice, ammonium chloride, and cocain; with rhubarb, angelica, Inula, saffron, fennel, gentian, zedoary root, myrrh, white agaric, camphor, and aloes in Warburg's Tincture. It occurs in several lozenge formulas with licorice and sassafras oil; with colts foot, licorice, sugar, acacia, horehound, wild cherry, anise, tolu, and Capsicum; with licorice, tolu, and sassafras; with colts foot, peppermint oil, licorice, tolu, anise, and Capsicum, and in other combinations of the same substances. It occurs in liquid products combined with buchu, nitrous ether, juniper berries, and Uva Ursi; with senna, Collinsonia, Hydrastis, Bikukulla, copaiba, and potassium iodide, and it is used as one of the ingredients of inhalant combinations with such substances as tolu, iodin, camphor, carbolic acid, and glycerin. A number of other species of Piper yield fruits resembling cubeb such as P. clusii of West Africa; P. borbonense of Bourbon; P. sumatranum and P. pedicellosum of India. The fruits of Toddalia lanceolata (Rutacese), of Litsea citrata and L. cubea (Lauracese) have been sold and substituted for genuine cubeb. The constituents of genuine cubeb thus far definitely determined are a volatile oil amounting to 10-20 per cent and consisting chiefly of terpenes, sesquiterpenes and sesquiterpene hydrate called cubeb camphor; resinous matter; a bitter principle, cubebin; an acid called cubebic acid (sup- posed to be the cause of the characteristic red color produced when an ethereal extract of cubeb is treated with sulphuric acid); starch, and fixed oil. The stem-free fruit yields about 20-25 per cent of its weight to ether. If a small portion of the ether-free extract is treated with a drop of con- centrated sulphuric acid, 1 mil of ether added and rotated until the ether is evaporated, a crimson color is obtained. Adulterated samples give a red color with brown streaks intervening, while spurious products give a brown color and a mace odor. BOTANICAL DRUGS 421 Cubebin Cubebin has the composition C20H20O6. It forms white crystals melt- ing 132°, (a)z>= —45.45 in chloroform, soluble in alcohol and ether. It contains two hydroxyl groups. When dissolved in glacial acetic acid and dehydrated with hydr iodic acid cubebinic ether results. This sub- stance melts 78°, (ol)d = +23.04° in chloroform, forms white silky needles, soluble in alcohol, benzol, acetic acid, and chloroform, and but slightly in water. It contains no hydroxyl nor carbinol groups and is not acted upon by bromin, permanganate, or hydrogen peroxide. Cubebinic ether yields a primary alcohol, cubebinol, when reduced with alcohol and so- dium. Cubebinol crystallizes in silky needles, melting 92°, (o)d= +34.81° in chloroform, yielding an acetyl derivative melting 71°, (o)d= +23.12° in chloroform and a benzoyl derivative melting 154-155°, (a) D = —21.68° in chloroform. Cubeb Oil Cubeb oil is a viscid, light-green or bluish-green oil; colorless only when the last portions of the distillate winch are blue, are not added; specific gravity .905 -.925, (a) D = -20 to -40°. The solubility in 90 per cent alcohol varies, some oils being soluble in an equal part of the alcohol, others requiring a greater quantity. Oils distilled from old fruit are heavier than the normal and can be recognized by their action on potas- sium or sodium. A piece of freshly cut metal immersed in such an oil loses its luster, whereas an oil distilled from the fresh berries does not attack metal. The oil has the characteristic cubeb odor and a warm camphor-like taste, which finally becomes grating. CANNABIS SATIVA. (CANNABIS INDICA) The drug consists of the flowering tops of the pistillate plants of Can- nabis sativa (Cannabinacese) , an annual herb indigenous to Central and Western Asia and cultivated in India, Greece, and other tropical and temperate countries. Cannabis is used in remedies for delirium tremens, certain forms of insanity, mania, excessive and painful cough, tuberculosis, migrain, itch- ing of eczema, neuralgia, and severe pain of different kinds, and corns. It is also extensively employed in veterinary practice. In pills or tablets it is combined with ergot; phosphorus and iron carbonate; with sumbul, Hyoscyamus and Valeriana; with arsenous acid and reduced iron; with Digitalis and reduced iron; with zinc phosphide and hyoscyamin; with phosphorus, strychnin, and damiana; with Hyos- cyamus, Ignatia, opium, belladonna, Conium, Stramonium, and aconite; 422 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS with coca, Valeriana, strychnin, codein, arsenous acid, and ferrous car- bonate; with strychnin, aconitin, zinc phosphide, and sodium arsenate; with morphin, Capsicum, Hyoscyamus, nitroglycerin, and oil peppermint ; with quinin, Hyoscyamus, strychnin, acetanilid, and arsenous acid; with Hyoscyamus and the bromides of sodium, potassium, and ammonium. Liquid preparations will follow the general type of the above men- tioned combinations. The well-known " chlorodyne " type of remedies, popular for colic, cholera morbus, neuralgia, etc., contain Cannabis sativa, morphin, Capsicum, hydrogen cyanide, chloroform, and oil of pepper- mint. Anodyne mixtures contain Cannabis sativa, Hyoscyamus, chloral, and potassium bromide. Corn remedies consist of a mixture of this drug and salicylic acid with collodion or an ointment base. Cannabis contains from 15-20 per cent of a resin (called cannabin) consisting of a number of substances, one of which cannabinol, occurs as a red oily substance. Cannabinol appears to be the substance which gives the drug its peculiar active properties. It has the empirical formula C21H30O2, and is very unstable. It has been separated from the drug and the method employed may be followed in isolating it for the purpose of testing. The sample is extracted with low-boiling petroleum ether and after recovering the solvent the resin is distilled under .1 mm. pressure in Claisen flasks fitted with Thome's taps. The fractions passing over between 190-230° are united, dissolved in alcohol and subjected to a freez- ing temperature to remove paraffins. The alcoholic solution is distilled under diminished pressure in a current of hydrogen to remove the alcohol and the residue again fractionated, using the same procedure as above at a pressure o f 0.1 m m. U^annabinol distills at 230° at this pressure. It is readily altered on exposure to air and light and loses its physio- logical activity. This change, due to oxidation, occurs in alcoholic and ethereal liquids, and is responsible for the loss of activity of the galenical preparations. It contains an hydroxyl. It forms a trinitroderivative and by the further action of nitric acid a complex substance, C23H29N3O12, and ultimately butyric and oxalic acids. Solutions of cannabinol in glacial acetic acid have a characteristic marked dichroism, being green by transmitted and red by reflected fight. The addition of alkali hydrox- ides to an alcoholic solution produces a deep-red color which is discharged by the addition of an acid. A petroleum ether extract of Cannabis or a petroleum ether extract of an evaporated alcoholic extract of the drug, on evaporation to dryness and treatment with absolute alcohol which has been saturated with dry hydrochloric acid gas, yields a bright cherry-red color which will disappear on dilution with alcohol or water. The same color is developed by con- centrated sulphuric acid in acetone or acetic acid solutions of the extract. BOTANICAL DRUGS 423 Cannabis sativa or its active principle are best detected by their peculiar action on dogs. Shortly after receiving a suitable dose the animal vomits and becomes excitable, later incoordination follows, the dog loses control of its legs and the muscles supporting the head, so that when standing the feet are usually spread apart to maintain balance. A third stage finally develops in which the dog sinks to the floor as if exhausted, and passes into a deep sleep. Preparations known to consist only of Cannabis may be administered directly by means of hard gelatin capsules, but where the drug is suspected in complex mixture the active principle should be extracted by means of petroleum ether, or if this is impracticable, with alcohol. The alcoholic extract may be administered directly, but if petroleum ether is used the solvent should be recovered and the residue tested. Corn remedies are best treated with ether and the solution poured into absolute alcohol, when most of the inert material will separate out and the clear liquid can be used for testing. The mixture itself will often yield its Cannabis to the alcohol without dissolving in ether. The animal's mouth is opened by forcing the thumb and index finger of the left hand between the jaws back of the teeth. The capsule is then placed on the back of the tongue with the right hand and the mouth quickly closed; while still holding the mouth shut, the animal can be made to swallow the capsule by slapping it on the throat. The quantitative estimation of Cannabis sativa is at best only a measure of comparative activity. Any data obtained from any kind of a galenical preparation mean little except as to the relative activity of the particular product with respect to Cannabis. The activity of a dozen samples of drug answering the description of the Pharmacopoeia may all come within an average and a dozen other samples of the same appear- ance fall far below them. A pill, a liquid mixture, or a solid extract may have a certain comparative potency measured in respect to a high grade sample of crude drug, but the figure obtained on the unknown cannot be used as a basis for stating the actual quantity of drug present. The method of assaying Cannabis has already been described. Within recent years the cultivation of the drug has been developed in the United States and the quality of the product is equal to any that was formerly imported. The plant is bisexual, the male and female flowers being produced on separate individuals, and the drug consists of the tops and unfertilized flowers of the female. The reason for this peculiar dis- crimination is somewhat obscure, for investigation has disclosed that the male tops which are culled out from the field, possess a physiological action of the same character with an equal degree of potency as the female portions. In the eighth revision of the Pharmacopoeia, one of the specifications 424 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS of the official drug was that its source should be the East Indies, though as an actual fact most of the shipments came originally from Greece. It is healthful to note that the East Indian myth has been left out of the ninth revision, but the unfertilized female tops are still the only portions recognized as representing the drug. There is undoubtedly good reason for demanding that the female tops should be unfertilized, but the reason for exclusion of the equally active male tops is not apparent. There is still a lingering disposition in the trade to distinguish between so-called Cannabis Indica and Cannabis Americana, and an imported and often inferior article is quoted at a higher price than the native grown. Both products are one and the same, however, and there is no more reason for discriminating between them than there is for trying to draw a dis- tinction between methyl salicylate and oil of gaultheria or between wild and cultivated ginseng or between first- and second-year Digitalis. HOPS Hops extract and the glandular powder called Lupulin are used medi- cinally for their tonic, sedative, and anaphrodisiac properties. They will be encountered in many tonic mixtures combined with malt, hypo- phosphites, glycerophosphates, Nux Vomica, etc. ; and in various sedative formulas with Scutellaria, Cyprepedium, lactucarium, and bromides. They are also used in gonorrhea and other irritated conditions of the genito- urinary organs. Their virtues seem to be adaptable either for the produc- tion or relief of sexual excitement, for combinations of hops with phos- phorus, zinc, and strychnin are used as remedies for restoring sexual tone, and combinations with Scutellaria, bromides, and other sedative drugs are prescribed for producing the opposite effect. The hop plant, Humulus lupulus, is now placed in the family Can- nabinacese, and the male and female flowers are produced on separate plants. The male flowers are yellowish white and arranged in panicles, the female are pale green and disposed in solitary, peduncled aments. The part of the plant used is the fruit or strobile. Lupulin is formed on the surface of the scale and in the dried fruit, existing in the state of very small granules. It is obtained by rubbing or threshing and sifting the strobiles, of which it constitutes from T V to -g- by weight. It is a yellowish powder, with the characteristic hop flavor and under the microscope is seen to consist of globules filled with a yellow matter. It is inflammable and when moderately heated becomes some- what adhesive. Lupulin should contain not more than 40 per cent of matter insoluble in ether and yield not more than 12 per cent of ash. A vast amount of literature exists concerning the chemistry of hops, but much of it is vague and empirical and it has remained for Power, BOTANICAL DRUGS 425 Tutin, and Rogerson 1 to clear up many of the disputed points and to give us the first authoritative insight into the chemistry of the drug. An alcoholic extract of hops on evaporation yields a volatile oil having a characteristic hop odor, extractive matter, and about 14-15 per cent of a dark-green oily resin. From the portion of the extract soluble in water there may be isolated small amounts of cholin and Z-asparagin, tannin, potassium nitrate, a sugar yielding c/-phenylglucosazone, melting 208°, and dark-colored, intensely bitter amorphous material. A volatile base with a coniin-like odor is also present, but has not been 'identified. From the resin the following compounds have been isolated : ceryl alco- hol; hentriacontane, C31H64; a phytosterol, C27H46O; a phytosterolin (phytosterol glucoside), C33H56O6; a mixture of volatile fatty acids con- sisting of formic, acetic, butyric, valeric, a hexenoic acid, C6H10O2, boil- ing 204-208° identified as /3-isopropylacrylic acid, and nonic acid; satu- rated and unsaturated non-volatile acids including palmitic, stearic, cero- tic, linolic, cluytinic, C21H42O2, melting 69°; and an acid, C20H40O2; an isomer of arachidic acid; and two new crystalline phenolic substances, humulol, C17H18O4, melting 196°, with a pale-fawn color and a bitter taste, and xanthohumulol, C13H14O3, melting 172°, orange-yellow in color and tasteless. Humulol is soluble in sodium carbonate, but not in ammonium car- bonate or hydroxide. The alkaline solution is j-ellow deepening on stand- ing or when warmed. It gives a pale-yellow solution with concentrated sulphuric acid. Its alcoholic solution is uncolorecl by ferric chloride. It is insoluble in water, petroleum ether, or benzol, sparingly in ether and chloroform, more so in glacial acetic acid, and readily in alcohol and pyridin. When boiled with potassium hydroxide, humulol is resolved into p- hydroxybenzaldehyde, melting 118°, and giving a dark-violet color with ferric chloride, a crystalline acid, C15H14O5, melting 210°, and complex viscous products. Xanthohumulol is not decomposed on heating with potassium hydrox- ide, but dissolves with an intense yellow color. Its alcoholic solution is not colored by ferric chloride. With sulphuric acid the color is at first deep orange, but this soon fades to a colorless solution. It is readily soluble in ether, ethyl acetate, and pyridia, moderately in alcohol, and sparingly in benzol and glacial acetic acid. The authors conclude that the bitterness of hops is not due to any single substance, such as the so-called " hop-bitter acid " or " lupulic acid," but it is attributed to a number of amorphous substances and humulol. Some of these bitter substances are soluble in water while others are in the resin. The differentiation of the resinous materials as a, 0, and 7 1 Trans. Chem. Soc, 103, 1913, 1267, 426 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS resins probably has little significance, and in our work at least does not call for further comment. The presence of hop extract in a medicinal mixture is usually apparent by the odor. An aqueous decoction of an evaporated alcoholic extract of the sample will contain the amorphous bitter substance, which is remov- able by ether, after acidification, and thus easily separated from strychnin. An ethereal solution of the resin, after first washing with ammonium carbonate, will yield humulol to sodium carbonate, and by subsequent shaking with potassium hydroxide the xanthohumulol is extracted. Both of these phenolic substances can be recovered by acidifying the alkaline solutions and shaking out with ether. The identification of a small quantity of potassium nitrate in the sample will furnish further evidence of the presence of hop extract. COCILLANA BARK This drug, which has become a very valuable remedj^ for bronchial troubles, was discovered by Dr. Rusby. The tree, Guarea rusbii (Meli- acese), is a native of Bolivia, and the thicker bark from the trunk and branches furnishes the drug. The bark has a peculiar and rather nauseating odor and nauseous taste, and this characteristic is imparted to the extract. If ipecac is absent in remedies recommended for deep-seated coughs, the presence of cocillana may be suspected. It contains a small quantity of an alkaloid, about 2.5 per cent of resin- ous matter, 2.5 per cent of fixed oil, and a white crystalline hydrocarbon- like body, melting at 80° C, sublimable, with a peculiar aromatic odor, soluble in ether, chloroform, acetic ether, and acetic acid. PHYTOLACCA DECANDRA. POKEWEED. The pokeweed is a familiar plant all over the eastern portion of the United States. It is a rapid grower, the stalks often attaining a height of nine feet with a spread of equal diameter. The dark-purple berries ripen in the autumn and both these and the root are gathered and used as drugs. As an alterative the drug appears in remedies for syphilis combined with Stillingia, Smilax Pseudo-China (Bamboo brier), Xanthoxylum, and Lappa; or with red clover blossoms, Berberis aquifolium, Cascara amagra, Stillingia, Lappa, and potassium iodide, sometimes with Iris versicolor; as an antirheumatic it occurs with colchicin, digitalin, guaiac, and potas- sium iodide; and with lithium salts, salicylates, cimicifuga, and colchicin. It is also found in remedies for catarrhal conditions of the mucous mem- BOTANICAL DRUGS 427 brane, obesity, tumors, congestions of the uterus, liver, etc., and consti- pation, and it has emetic properties. The organic constituents of the root have never been fully investi- gated, but they are reported to include a saponin-like substance, an alka- loid, starch, sugar, formic and other acids. The inorganic constituents amount to over 13 per cent and consist principally of potassium and calcium, probably in the form of formate and oxalate respectively. The fruit of Phytolacca abyssinica is reported to be a tape-worm expellant. HYDRANGEA ARBORESCENS. (HYDRANGEACE^) The wild hydrangea or seven barks is an indigenous shrub of the eastern portion of the United States south of southern New York. The root has long been esteemed as a remedy for calculus complaints, and is often present in cystitis mixtures combined with boric or benzoic acid, potassium bicarbonate, buchu, triticum, corn-silk, Viburnum prunifolium, and atropin. It will be found in combination with hthium salts; and with Uva Ursi and matico in elixirs. An aqueous solution of the alcoholic extract of the drug fluoresces on adding alkali. The presence of a crystalline glucoside, a saponin-like body, a sugar, and resinous constituents have been reported. A peculiar characteristic of the shrub is the peeling off of the stem bark, which detaches in several successive thin layers of different colors, and which has given rise to the popular name " Seven Barks." KRAMERIA. RHATANY Several rhatanies have appeared in the market, and there are three well-recognized commercial species, Peruvian rhatany, the root of Kra- meria triandra (Krameriacese) (Leguminosse) growing in Peru and Bolivia; Savanilla rhatany, from K. ixina, and possibly other species, growing in Colombia, Brazil, and British Guiana; Para or Brazilian rhatany from K. argentea of Brazil. Krameria has been used in a multitude of ailments, but is nowhere common. It owes its chief value to its astringency, though it is likewise slightly tonic. It is employed internally in menorrhagia, passive hemor- rhages, chronic diarrhea, mucous discharges, leucorrhea; locally for piles, anal fissure, and prolapsus ani, and as a styptic in oral hemorrhage of surface bleeding. In pills it will be found combined with cubeb and ferrous sulphate; with bismuth salts, opium, and licorice; in capsules with copaiba and cubeb; and in pile ointments with sulphur, zinc oxide, resorcin, stramonium, tannic acid, and oil of cade. The Para rhatany closely resembles the Savanilla variety. The drug contains from 8-20 per cent of tannic acid or a tannin-like substance 428 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS giving a dark-green color with ferric salts. Starch, sugar, and calcium oxalate are also present. Krameria lanceolate of the Southern United States furnishes the Texas krameria, and K. cistoides of Chile is the source of the Payta krameria. The root of Leea speciosa (Yitacese) has been used as a substitute drug. The tincture of Savanilla rhatany forms a clear solution with water, which gives, with alcoholic lead acetate, a purplish precipitate and a color- less nitrate. The tincture of Peruvian rhatany gives a cloudy mixture with water, and a reddish-brown precipitate with alcoholic lead acetate with a light-brown filtrate. HAMAMELIS VTRGINIANA. WITCH HAZEL Distilled extract of Hamamelis virginiana (HamameHdacese) is a house- hold remedy for inflammatory conditions, sprains and bruises. The distilled extract is prepared both from the leaves and the bark which are macerated with alcohol of from 6-10 per cent strength and then subjected to distillation. A concentrated extract of the drug, representing the resinous portion, is called Hamamelin. This is considered of value as a remedy for piles, and may occur in ointments intended for this trouble. The extract is sometimes used in pill mixtures recommended for disorders of the female genito-urinary tract, and may be combined with hydrastin, Hyoscyamus, opium, Senecio, tannin, thymol, Chamalerium luteum, salicylic acid, boric acid, alum, and eucalyptol. The distilled extract is combined with glycerin, boric acid, and mucil- age of Irish mosb in lotions and jellies for sunburn, freckles, and inflam- matory conditions of the skin. TRIFOLIUM PRATENSE. RED CLOVER Hed clover blossoms of T. pratense and T. incarnatum (Fabaceae) are employed medicinally in alterative mixtures for scrofula and second- ary syphilis, in whooping cough remedies, and for washing ulcers. In alterative preparations the drug is combined with others of similar repute such as Stillingia, Xanthoxylum, Lappa, Phytolacca, Iris versicolor, Ber- beris aquifohum, Cascara amagra, Smilax species, and potassium iodide. The flowering tops of T. pratense ordinarily furnish the drug known as red clover blossom. The blossom is well known and needs no de- scription. It is the red, purple, or meadow clover. Power and Salway x reported the following summary of a chemical investigation made on this drug. An essential oil distilled from the alco- holic extract contained furfur aldehyde. The water-soluble portion of the 1 Chem. Soc. Trans., 1910, 97, 231. BOTANICAL DRUGS 429 alcoholic extract contained considerable sugar, yielding d-phenylgluco- sazone; salicylic and p-cumaric acid; iso-rhamnetin; a number of new phenolic substances; pratol, Ci 5 H 8 2 (OH)(OCH3), melting 253° C; pra- tensol, Ci 7 H 9 2 (OH)J, melting 225°; a substance, Ci4Hi 2 6 , melting 214°; the following glucosides — trifolin, C22H 2 20ii-H 2 0, melting 260°, which yielded on hydrolysis a yellow coloring matter trifolitin, Ci6Hi O 6 , melt- ing 275°, and rhamnose, C6H12O5; isotrifolin , C22H22O11, melting 250°; and quercetin, melting 235°. The portion of the alcoholic extract insoluble in water was chiefly resinous material. The following substances were obtained from it: myricyl alcohol; heptacosane; hentriacontane; sitosterol, C27H46O/ melt- ing 135-136° (cOz>= -34.4° in chloroform; lnfohaiiol_C2iH3402(OH)2, melting 295°; a dihydric alcohol; a mixture of fatty acids, chiefly pal- mitic, stearic, and linolic, and a small amount of pratol. The tops of T. incarnatum, the crimson, carnation, French or Italian clover, are terminal, oblong or ovoid 1-2 J inches long; flowers sessile §-§ inch long, calyx hairy, corolla crimson, equaling or exceeding the subulata plumose calyx-lobes. Rogerson 1 examined the flowering tops of the plant and obtained a small quantity of an essential oil, and in the aqueous solution of the alco- holic extract there were present a sugar yielding tf-phenylglucosazone, benzoic, and salicylic acids, pratol, quercetin, and a new glucoside, h> carna trin, C 2 iH 2 oOi 2 3H 2 0, melting 242-245°. The portion of the alcoholic extract insoluble in water consisted of a green resin, amounting to 4 per cent of the dried tops, from which were isolated incarnat yJL alcohol^ C34H69OH, melting 72-74°; hentriacontane; a phytosterol, C27H46O, melting 135-136° (a) D =— 41.7° in chloroform; trifolianol, and a mixture of fatty acids. Pratol This phenol, together with other substances, is removed by ether from an aqueous decoction of the alcoholic extract of the drug. On evaporat- ing the ether and subsequently treating the residue with insufficient ether to bring it entirely into solution, the pratol is left undissolved. It crys- tallizes from alcohol in needles, having a talon-like shape with curved edges. It is moderately soluble in hot alcohol but only sparingly in water, ether, chloroform, and benzene. It dissolves readily in hot aqueous sodium carbonate and hydroxide, yielding pale-yellow solutions. When dissolved in acetic anhydride and a drop of sulphuric acid added, a yellow coloration is produced. With ferric chloride no appreciable change in color is produced. 1 Chem. Soc. Trans., 1910, 97, 1004. 430 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Power and Salway state that pratol is isomeric with several flavone derivatives such as the 2-methoxy and 3-methoxy-flavonol X) — C C 6 H 5 CH 3 OC 6 H 3 < | XJ-OC-OH Its general behavior is similar to that of the above-mentioned substance, and it may represent one of the many hydroxymethoxy-flavones which are theoretically possible. Pratensol This phenolic substance goes into ether with comparative ease, and may be removed therefrom by alkali carbonates. It is readily soluble in alcohol and acetic acid, but only sparingly in water, chloroform, and benzene. Its alcoholic solution gives with ferric chloride a greenish- black coloration. Trifolin Trifolin gradually separates from the aqueous decoction of the alco- holic extract of the drug. On purification by repeated crystallization from aqueous pyridin it crystallizes in pale-yellow needles, which melt with decomposition at 260°. The water of crystallization is expelled at 115°, but on exposure to the atmosphere this is reabsorbed. It is insoluble in cold water, chloroform, benzene, and ether. It is sparingly soluble in alcohol, but dissolves with ease in pyridin. With aqueous sodium carbonate and hydroxide it gives intensely yellow solutions. It dissolves in concentrated sulphuric acid to a yellow solution which rapidly develops a green fluorescense. In alcoholic solution it gives with ferric chloride a dark-brown color. When trifolin is hydrolyzed by sulphuric acid in alcoholic solution, it is resolved into trifolitin and rhamnose. C22H22O11 = C16H10O6+C6H12O5 Trifolitin separates, after distilling off the alcohol, as a yellow precipi- tate, readily soluble in alcohol and glacial acetic acid, but only very spar- ingly soluble in ether, chloroform, and benzol. It dissolves in alkalies with an intense yellow color, and dyes mordanted cotton wool a bright yellow. It is precipitated from its alcoholic solution by lead acetate as an orange-yellow lead salt. Its alcoholic solution gives a dark-green color with ferric chloride. Isotrifolin This glucoside is soluble in water and may be removed therefrom by amyl alcohol. It yields the same hydrolytic product as trifolin, but it BOTANICAL DRUGS 431 is evidently not identical with it. It melts at 250° and is much more soluble. Its general behavior is close to trifolin. It dissolves in alkalies with the formation of a deep-yellow solution, and gives with sulphuric acid a yellow color together with a green fluorescence. In alcoholic solu- tion it gives with ferric chloride a deep-brown color. Incarnatrin Incarnatrin, the glucoside of T. incarnatum, is soluble in water and is removed from the aqueous solution of the evaporated alcoholic extract of the drug by amyl alcohol, subsequent to the extraction of the phenols with ether. It hydrolyzes to quercetin and a sugar. C21H20O12+H2O = O5H10O7+C6H12O6 The quercetin is soluble in ether, from which it may be removed by sodium carbonate. Incarnatrin is hydrolyzed by emulsin. It dissolves slowly in con- centrated sulphuric acid with a yellow color and a green fluorescence. XANTHOXYLUM The dried bark of Xanthoxylum americanum (Rutacea?) and of X. Clava-Herculis is official under the general name of Xanthoxylum. The berries are also used to a considerable extent. Both species of Prickly ash occur in the eastern portion of the United States, the former being the northern species or Toothache-tree and the latter the southern prickly ash, Hercules Club, or Pepper-wood. As a drug Xanthoxylum is used as an alterative, stimulant, and siala- gogue, and will be found in remedies for rheumatism, toothache, syphilitic and hepatic affections for increasing the secretions, and externally as a count er-irritant. Some of the liquid combinations which are recommended especially as alteratives or blood purifiers contain in addition to Xanthoxylimi, Bicuculla canadensis, Stillingia, Iris versicolor, and potassium iodide; or Trifolium pratense, Arctium lappa, Berberis aqiufohmn, Stillingia, Phytolacca, Cascara amagra, Bamboo-brier, and potassium iodide; liquid products in which the extract of the berries functionates contain also Stillingia, Bicuculla, Chimaphila, Iris, Sambucus, and coriander. Reme- dies in tablet form are of the same general type and in addition will be found tonic mixtures containing Cinchona alkaloids, Capsicum, and Cor- nus florida; ague pills with Cinchona alkaloids, Capsicum, and Gelsemium; and combinations with Cascara sagrada, Belladonna, Xux Vomica, Euony- mus, and Capsicum. The powdered bark is chewed as a remedy for tooth- ache and is also combined with Capsicum as a pack for pelvic pains. 432 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS There are alkaloidal principles in this drug, but their identity is as yet uncertain. Formerly berberin was considered one of the constituents of the bark, and when chewed the saliva is colored yellow, but later investigation has cast some doubt on the identity of the alkaloid. Jowett and Pyman found canadin and gamma-homochelidonin in X. brachyacan- thum, but the chemistry of the Xanthoxylums needs further study. EUPHORBIA PILULIFERA Euphorbia pilulifera (EuphorbiaceaB), Queensland asthma herb, is an annual herbaceous plant growing in tropical countries and is reputed to be of value in the treatment of bronchitis, asthma, and other diseases of the respiratory organs. An extract of the entire plant is used in medi- cine and it is usually combined with iodides, bromides, Lobelia, and nitroglycerin, the combinations being dispensed in tablet and elixir form. Power and Browning x conducted an extensive chemical research on the drug and from the portion of the alcoholic extract which was soluble in water the following substances were isolated; gallic acid; quercetin, C15H10O7; a new phenolic substance; amorphous glucosidic material; a sugar yielding a phenylglucosazone, melting 218-220°, and a trace of alkaloid. The portion of the alcoholic extract insoluble in water consisted of soft, resinous material amounting to 3.2 per cent of the weight of the crude drug. This resin yielded triacontane, C30H62; ceryl alcohol; a new mono- hydric alcohol euphosterol, C25H39OH, melting 274-275°; a phytosterol, melting 132-133°; a phytosterolin (phytosterol glucoside); jambulol, Ci6H304(OH)5; melissic, palmitic, oleic, and linolic acids. About one-half of the resin is soluble in petroleum ether and after separating the solvent, extracting the undissolved portion with ether and separating the latter, the jambulol is obtainable by treatment with hot chloroform, from which it is partly deposited on cooling. Subsequent to this investigation it has been shown that jambulol is identical with ellagic acid. STILLINGIA Stillingia sylvatica (Euphorbiacese) is an herbaceous perennial found in dry sandy soil and in pine barrens from Maryland southward, and westward to Kansas and Texas. The root is esteemed for its alterative properties and is a popular component of spring tonics and blood puri- fiers. Stillingia will be found in elixirs, syrups, extracts, pills, and tablets combined with one or several of the following drugs : Bicuculla canadensis, Chimaphila, Iris versicolor, Sambucus, Xanthoxylum, Arctium lappa, 1 Pharm. J. ; 1913. BOTANICAL DRUGS 433 Phytolacca, Bamboo-brier, Trifolium pratense, coriander, and potassium iodide. Stillingia root contains a small quantity of volatile oil and an alkaloid. jKAMALA Kamala consists of the glands and hairs from the capsules of Mallotus PhiUipinensis syn. Rottlera tinctoria (Euphorbiacese) . The fruit is a roundish, three-valved, three-celled capsule of about the size of a cherry, marked externally with three furrows, and thickly covered with a red powder, which, when separated from the capsules, constitutes the official drug. It is used principally as a tape-worm expellant combined with aspidium in a medium of olive oil and dispensed in capsule form. The tincture is administered for tape worm, and the ointment for ring worm and parasitic skin diseases. Kamala is a light, finely granular, very mobile powder of a brownish- red, or madder color, with slight odor or taste but producing an acrid sen- sation in the mouth and a gritty feeling between the teeth. It is inflam- mable. It is insoluble in cold and very slightly in boiling water, largely soluble in ether, alcohol and alkalies. The chief constituent of kamala is a resin, the composition of which has not been reported. The ash of the pure drug should not run over 8 per cent, but in adulter- ated specimens it may reach as high as 50 per cent or more. Formerly much of the kamala imported was adulterated with sand and reddish earth, but this condition has been improved during recent years. EUONYMUS ATROPURPUREUS. WAHOO The root-bark of Euonymus atropurpureus (Celastracese) , known as burning bush or spindle tree, is employed to a considerable extent medi- cinally, and is recognized in the National Formulary and British Pharma- copoeia. The name " wahoo " is applied indiscriminately to E. atro- purpureus and E. americanus, the latter a low or trailing bush having crimson capsules to which the appellation " burning bush " is perhaps more applicable. Both species are used in medicine, but the former only is official. The extract is often combined with Podophyllum resin in remedies for the liver. It is precribed for intermittent fevers and dj^spepsia, and as a laxative, antiperiodic, and tonic. A crude resinous product or con- centration, and an alcoholic extract of the drug, are known under the name of " Euonymin," and the term is also applied to a number of sub- stances which at one time or another have been obtained from the bark, 434 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS all of which, however, are of indefinite character. Some extracts with a greenish color are obtained from the tree bark, and these appear to be equally active physiologically. Euonymus extract is dispensed alone in pills, tablets, and elixirs, and in various combinations with Cascara sagrada, belladonna, Capsicum, Nux Vomica, and Xanthoxylum; with Taraxacum, Podophyllum, Apo- cynum, Eupatorium, Capsicum, and Chelone; with Iris, Podophyllum, and Sanguinaria; and with Podophyllum, ipecac, aloin, and calomel. Rogerson 1 made a systematic chemical examination of the root bark of E. atropurpureus. An alcoholic extract when distilled with a current of steam yielded a small quantity of a fragrant, yellow volatile oil. The portion of the extract soluble in water, contained a quantity of dulcitol, amounting to about 2 per cent of the weight of the drug; a new acid, C5H4O3, melting 121-122°, evidently furan-/3-carboxylie acid; a new ^crystalline alcohol, C21H30O4, melting 248-250°, designated euonymol; a sugar which yielded a d-phenyl-glucosone, melting 208-209°, small amounts of tannin and coloring matter. The portion of the extract insoluble in water consisted of a dark-brown resin which amounted to 3.2 per cent of the weight of the drug. From this resin the following substances were isolated: euonysterol, C31H51O — OH, melting 137-138°, (a)/)-28.2°; ^homoeuonysterol, C 4 oH 69 0-OH, melting 133-134°; atropurol, C 2 7H44(OH) 2 , melting 283-285°; citrullol, C22H3602(OH)2, a substance previously isolated from colocynth; and a mixture of fatty acids consisting of palmitic, cerotic, oleic, and linolic acids. Citrullol is probably a phytosterol glucoside and it is not unlikely that some of the other substances above mentioned may belong to the same class. Euonymol is bitter, soluble in alcohol and ether, from which it is not removed by acids or alkalies. If a crystal be dissolved in a small quantity of acetic anhydride and a few drops of concentrated sulphuric acid added, a pink color develops, changing to green with a bronze fluorescence and finally becoming yellow. When dissolved in sulphuric acid it gives a yellow solution with a greenish-yellow fluorescence. When boiled with acetic anhydride and the resulting product recrystallized from ether and ethyl acetate, the acetyl derivative melts 215°. Euonysterol resembles the phytosterols in its reaction with acetic anhydride and sulphuric acid, but with concentrated sulphuric acid alone a red color is produced. Its acetyl derivative melts 116-118°. Homoeuonysterol also gives a red color with sulphuric acid. Its acetyl derivative melts 128-130°. Atropurol gives no color reaction with sulphuric acid alone, but with 1 Trans. Chem. Soc, 101, 1912, 1040. BOTANICAL DRUGS 435 acetic anhydride resembles the phytosterols. Its acetyl derivative melts 169-170°. Furan-/3-carboxylic acid is isomeric with pyro-meconic acid. It gives no color with ferric chloride. It is volatile with steam and sublimes 110°. Previous workers have reported the existence of a well defined gluco- side called euonymin, having a physiological action resembling that of the Digitalis glucosides, but Rogerson was unable to confirm this con- tention. SUMBUL Sumbul or Musk Root consists of the dried rhizome and roots of an umbelliferous plant which the U. S. Pharmacopoeia designates as Ferula sumbul. There is some doubt as to the identity of the botanical individual yielding the drug which is at present sold on the market. Sumbul is a nerve stimulant and is combined with Hyoscyamus, Valerian, and Cannabis; with ferrous sulphate, asafetida, and arsenous acid; with the valerianates of iron, zinc, and quinin; with iron, arsenous acid, and strychnin; and with Nux Vomica and Coca. Heyl and Hart 1 examined commercial musk root and found present a volatile oil amounting to 0.65-1.1 per cent, specific gravity .932 at 15°. This oil on standing deposited a few yellow crystals, melting at 113-114°, but not identified. No sulphur was found. An alcoholic solution of the drug yielded to water 1.7 per cent sucrose, 1 per cent levulose, acetic acid, betain, and a glucoside of umbelliferone. The portion of the alcoholic extract insoluble in water was of resinous character. On treating the resin with petroleum ether, there was obtained a considerable proportion of a white acid resin, soluble in 1 per cent potas- sium hydroxide, and yielding upon hydrolysis vanillic acid and an oil resembling the volatile oil. The petroleum ether portion also yielded a phytosterol, melting 134-135°; an unsaponifiable substance, boiling 168- 173°, at 12 mm., the analysis of which indicated the formula, C8H13O; and the following fatty acids from saponification of the glycerides, acetic, butyric, valerianic, tiglic, angelic, oleic, linoleic, cerotic, palmitic, and stearic. On subsequently treating the resin with ether, a phytosterolin, C33H56O6, melting 290° was obtained, also a trace of vanillin, resin esters yielding umbelliferone, and resin acids yielding vanillic acid and umbellif- erone on hydrolysis. Chloroform dissolved out a resinous glucoside which gave umbelliferone and glucose upon hydrolysis. An indication that sumbul is present in a medicinal preparation will be obtained in the regular scheme of analysis when the aqueous decoction of an alcoholic extract is made alkaline. On adding ammonia, for instance, 1 J. Amer. Chem. Soc, 1916, 432. 436 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS a yellowish-green flourescence is produced. This test is not specific as there are other drugs containing umbelliferone, and still others which produce blue or greenish fluorescences with alkalies. The odor of the drug differs markedly from that of asafetida and the volatile oil contains no sulphur. COTTON ROOT BARK Cotton root bark has obtained considerable reputation as an emmen- agogue and abortifacient, and is often present in female pills and in secret remedies advertised for restoring the menstrual periods. Some of the combinations containing the drug comprise ergot, aloes, savine, and fer- rous sulphate; Cimicifuga, aloes, and ferrous sulphate; ergot, Helleborus niger, aloes, savine, and ferrous sulphate. Pow T er and Browning 1 investigated the drug from a chemical stand- point. A concentrated alcoholic extract distilled with steam yielded a small quantity of a volatile oil which gave the furfurol color test, and deposited crystals of acetovanillone, melting 112-114°. The portion of the alcoholic solution soluble in water, and the insoluble resin contained a phenolic acid, probably 2-3 dihydroxybenzoic acid melting 196-199°; salicylic acid; a new phenolic substance, C9H10O3, melting 258-260°; a new yellow phenolic substance, melting 210-212°; betain; a fatty alcohol, C20H42O, melting 77.5-78.5°; a phytosterol; a small amount of an hydro- carbon, probably triacontane; ceryl alcohol; oleic and palmitic acids, and a sugar yielding d-phenylglucosazone. No tannins nor alkaloids were present. DAMIANA The drug damiana has been widely exploited in tonics and tonic bever- ages, as a remedy for restoring the sexual tone. In medicinal compounds it is usually combined with Nux Vomica or strychnin, phosphorus, zinc phosphide, cantharides, gold, and sodium chloride, and iron salts. Its presence should be suspected in any medicine used as an aphrodisiac. Tonic beverages which claim to contain damiana have been quite exten- sively marketed. These products usually bear striking pictorial devices of nude women and men in suggestive attitudes. As a rule the amount of damiana which is present in these mixtures is very small and often it is entirely lacking, and while sometimes the tonic may be fortified with strychnin or phosphorus, it usually consists of a mixture of water and alcohol, sweetened and flavored, and the picture is depended upon to stimulate the sexual activity. The leaves of more than one species of damiana occur in the trade, ipharm. J., 1914,93,420. BOTANICAL DRUGS 437 but the true drug is ascribed to Turnera diffusa var. aphrodisiaca, which is described as follows: Leaves with reddish stems, yellowish flowers and globular capsules may be present. Leaves 25 mm. long, oblanceolate to obovate, margin serrate-dentate, color light green (older leaves somewhat coriaceous and pubescent) odor aromatic, taste somewhat aromatic and bitter. The chemistry of damiana has never been reported, but it contains a small quantity of a volatile oil which gives the drug and its extract a characteristic odor, a small quantity of a bitter substance and a greenish resin. In pills, tablets, and elixirs the resin is easily found by evaporating an alcoholic extract of the sample and washing with water. The odor of damiana will then be apparent and the greenish resin left undissolved. In order to detect the presence of damiana in tonic beverages a sample of 100-200 mils should be evaporated to drive off the alcohol at the same time noting any odor which is evolved and comparing it with that given off by a known extract of authentic damiana previously prepared by the analyst ; often a slight characteristic odor will be the only thing that will indicate that damiana was ever used in making up the mixture. The residue is then transferred to a separator, rendered slightly acid if neces- sary and shaken out with Prolius mixture. The solvent is filtered, evapo- rated to dryness, the residue treated with warm water and the water decanted. If there is any resin present, it will be left in the residue and it may be treated with alcohol, collected in a small area, and the solvent carefully evaporated to prevent spreading. Damiana resin is of a deep dull-green color with a characteristic odor and is the most marked con- stituent of the drug. ASCLEPIAS TUBEROSA. PLEURISY ROOT The root of Asclepias tuberosa (Asclepiadacese), butterfly weed, or orange milk weed is the official Pleurisy root or Asclepias. The plant is a very showy perennial and is common all over the East and in the South- west, through Texas and Arizona. It differs from the other species of milkweed in having no milky juice in its stem. Pleurisy root will be found in stomach tonics, and it is also used in affections of the lungs to promote expectoration, to relieve tight breathing and pain in the chest. It will be found combined with opium, camphor, and potassium bitartrate, and the powdered drug is one of the components of a popular remedy for the liquor habit, which includes also Taraxacum, ginger, Capsicum, Angelica and bayberry bark. The chemistry of the root A. tuberosa has never been definitely deter- mined, but it probably contains considerable starch, and a resin which is 438 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS partially soluble in ether. The latter has been called asclepiadin, a gluco- side, but there is no evidence to show that it is an individual substance, and in view of our recent knowledge of these resinous bodies it is undoubtedly a mixture. Some of the other species of Asclepias have been used as medicines. A. verticillata is used in the South as a remedy for snake bites and the stings of venomous insects. A. syriaca is the common milkweed or silk- weed, and its root has been employed in asthma and scrofula. A. incar- nata, the flesh-colored or swamp milkweed is employed as an emetic and cathartic. The presence of milkweed roots in mixed liquid products can be detected only by the characteristic bits of vegetable tissue or of starch grains. The drug may occur in certain types of popular remedies mixed with rhubarb or other emodin-bearing drugs, buchu, juniper, • aromatic balsams, and sugars, and is recommended for alleviating abnormal conditions of the kidneys and stomach. ERIODICTYON. YERBA SANTA Eriodictyon calif ornicum syn. glutinosum (Hydrophyllacese), an ever- green shrub of California and Northern Mexio, is the source of the official drug Yerba Santa. The plant is also known as consumptive weed, tar weed, mountain balm, bears weed, and gum bark. It is employed for throat and bronchial affections as a tonic expectorant, and often occurs in preparations containing quiriin, for the purpose of obtunding the bitter- ness of that alkaloid. The drug contains a considerable amount of resin which is ordinarily insoluble in aqueous menstruum and syrups, and hence would be value- less for admixture with liquid quinin preparations unless prepared with a proportion of alkali sufficient to overcome the precipitation. The presence of an alkaline reaction therefore in quinin mixtures, and the pre- cipitation of resinous matter on adding acid, is a strong indication that Yerba Santa has been used. In medicines intended for expectorants it is combined with licorice, wild cherry, bromides, tar, Grindelia, salicylic acid, and senega, and it will be found in tablets, syrups, or glycerides. Power, Tutin, and Clewer 1 have examined the drug and the substances isolated therefrom. They determined that the leaves contain an essential oil, resins, amorphous products, glucose, the hydrocarbons triacontane, and pentatriacontane, formic, acetic, butyric, cerotic, and other acids, both in the free state and as glycerides, a small amount of a phytosterol, 1 Proc. Am. Pharm. Ass., 1906, 54, 352; Trans. Chem. Soc, 1909, 81; Trans. Chem. Soc, 1910, 97, 2054. BOTANICAL DRUGS 439 and five new crystalline substances of phenolic character ; / eriodicty ol, -" C15H12O6, melting 267°; ho moeriodic tyol, C16H14O6, melting 223°; cju^cse — ■» erid ol, C16H12O6, not melting up to 337°; xajitho^rioLol, C18H14O7, melting 258°, and eriodonol, C19H18O7+H2O, melting 199°, and when anhydrous, melting 209 . No alkaloidal substance was present. The total amount of crude resinous material in the leaves amounts to 29-30 per cent, about 75 per cent of which is soluble in ether. The crude resin has an odor suggestive of tolu. The phenolic bodies are the characteristic ingredients of Eriodictyon, and are found both on the resinous portions and in the aqueous decoction of the evaporated alcoholic extract of the drug. When the evaporated alcoholic extract is treated with boiling water, the aqueous solution con- tains eriodictyol" with a suspension of homoeriodictyol, which appears as a yellow solid on cooling. Further quantities of the latter substance with some of the former and the three other homologues are subsequently found in the resin. The aqueous solution obtained as above mentioned, after filtering from the separated homoeriodictyol, is shaken with ether which dissolves the eriodictyol, and the latter may then be extracted from the ether by a saturated solution of sodium carbonate, previously washing the ether solution with ammonium carbonate to remove resinous matter. On acidulating the alkaline solution and shaking with ether, the phenolic body dissolves and on evaporating the solvent it will be left as a yellow varnish, yielding pure fawn-like crystals on recrystallizing from hot alco- hol, after shaking with animal charcoal. The alkaline solution must be at once acidulated as the solution rapidly turns brown when exposed to the air. Power and Clewer in their work fractionated the resin by repeated extractions with sodium carbonate, and thus obtained the several high- melting phenolic substances above mentioned. The resin was first extracted with petroleum ether to remove the acid and hydrocarbon con- stituents and the residue treated with ether. The etheral solution after washing with ammonium carbonate, was extracted with 34 successive portions of 5 per cent sodium carbonate. For each of the first 15 fractions, 20 mils of the solution was employed, for each of the next 10, 50 mil por- tions, and for the remainder 100-mil quantities. The first and last frac- tions yielded only resinous matter, fractions 2-13 yielded xanthoeridol, 4-26 eriodictyol, 15-26 chrysoeridol, and 27-33 eriodonol. Homoerio- dictyol separated as a sodium compound, which was collected on a filter, washed with ether and a little water and then recrystallized from water. The procedure adopted by these chemists for the separation of the con- stituents of Eriodictyon has been detailed here in order to point out to the analyst of an unknown mixture, a method for determining the presence 440 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS of this drug. The systematic examination of a liquid or solid medicinal compound according to the qualitative scheme of analysis which is recom- mended for such mixtures, will furnish an aqueous solution and a residue of resinous character which can be adapted to the tests of Power and Clewer. Eriodictyol Tutin has determined that this substance is 2 : 4 : 6-trihydroxyphenyl 3 : 4-dihydroxystyryl ketone _ 0I L HO/ ~")>CH : CH : Co/~ \oH HO OH It forms fawn-colored plates from glacial acetic acid, darkening and melt- ing to a red liquid at 267° C, moderately soluble in hot alcohol and acetic acid, very sparingly soluble in boiling water and insoluble or very sparingly so in the other organic solvents. It dissolves readily in alkali carbonates and hydroxides, the solutions rapidly absorbing oxygen and becoming deep brown. Ferric chloride gives a deep greenish-brown color rapidly changing to pure brown, when added to an alcoholic or aqueous solution. Its saturated aqueous solution does not reduce Fehling's solution, is not appreciably precipitated by normal lead acetate, but with basic lead acetate it affords a bulky yellow precipitate. Its acetyl derivative melts 195-196°. On hydrolysis with acids it yields phloroglucinol. Homoeriodictyol (2:4: 6-trihydroxyphenyl-4-hydroxy-3-methoxystyryl ketone.) OH Ho/~ NcH : CH : Co/~ ~NoH CH3O ~~ OH Homoeriodictyol is the monomethyl ether of eriodictyol, and is readily obtained in a pure condition by dissolving in ether and shaking with sodium carbonate when a sodium derivative of homoeriodictyol separates, which may be recrystallized from water, and then decomposed by dissolving in hot water and adding dilute acetic acid. It crystallizes from 70 per cent acetic acid in lemon yellow plates, melting 223°. It is very sparingly soluble in water, but more readily in alcohol and acetic acid than erio- dictyol. It dissolves in alkalies with a bright yellow color. Its alcoholic solution gives an intense red-brown color with ferric chloride. Its aqueous solution is not precipitated by either of the lead acetates. No crystal- line acetyl or benzoyl derivatives have been prepared. It possesses a BOTANICAL DRUGS 441 very slight sweet taste. On hydrolysis it yields feriilic (4-hydroxy-3- methoxy cinnamic acid) and phloroglucinol. This body appears to occur in considerably greater amount than any of the other phenolic compounds, Power and Tutin reporting the pres- ence of 3 per cent. It is isomeric with hesperitin, which is obtained by the hydrolysis of the glucoside hesperidin, a constituent of the peel of the orange, lemon, and other related fruits. Hesperitin crystallizes in color- less needles, melting 226°, soluble in alkalies to a faint-yellow solution, and possessing a sweet taste. It yields isoferulic (3-hydroxy-4-methoxy cinnamic acid) and phlorogulcinol on hydrolysis. Xanthoeridol, CisHnO^OH^ Xanthoeridol crystallizes from a mixture of ethyl acetate and alcohol in tufts of soft yellow, needles melting 258°. Its solutions in alkalies and concentrated sulphuric acid are yellow, and an alcoholic solution gives a dark-brown color with ferric chloride. Its acetyl derivative when recrystallized from acetic anhydride melts 175-176°. Chrysoeridol, C 1G Hg0 3 (OH)d Chrysoeridol is easily separated from eriodictyol, with which it is associated on account of its slight solubility in alcohol. It separates from boiling alcohol in golden-yellow leaflets which do not melt up to 337°. Its color reactions are similar to those of xanthoeridol. Its triacetyl- derivative when crystallized from acetic anhydride melts 211-212°. Eriodonol, Ci 9 Hi 4 3 (OH)4 This substance crystallizes from slightly diluted alcohol in pale yellow needles containing one molecule of water melting 199°. When heated at 110° the water is expelled and the anhydrous body melts 209°. It is readily soluble in ethyl acetate, absolute ethyl, and methyl alcohols. When treated with concentrated sulphuric acid, the crystals become orange and dissolve to a yellow solution with a slight fluorescence. It gives a dark purplish-brown color with ferric chloride. Its solutions in alkalies are bright yellow. It yields iodoform when warmed with iodin and sodium carbonate, differing in this respect from the two substances previously described. It dyes linen mordanted with alumina or iron, bright yellow or dark brown respectively, and is thus similar to the tetramethyl ether of quercetin. It forms a tetracetyl derivative, melting 131°. PICHI Pichi is the dried leafy twigs of Fabiana imbricata (Solanaceae), a shrub with small scale-like leaves, indigenous to Chile. It contains a volatile oil, a bitter alkaloid, resin, and a substance resembling aesculin. 442 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Pichi will be found in diuretic mixtures combined with corn-silk and triticum. An aqueous liquid obtained by washing an evaporated alcoholic extract of pichi shows a pink fluorescence when acidulated. The color turns blue on adding ammonia, the fluorescence persisting. The resinous portion of the drug contains a resene which is soluble in ether and may be sublimed. The resene obtained in this way gives a yellow color with concentrated sulphuric acid, becoming red on warming. When dissolved in carbolic acid, treated with zinc chloride and warmed, a yellow-brown color is obtained; on adding concentrated sulphuric acid, a rose-red color appears, soon changing to purple. COLLINSONIA CANADENSIS. STONEROOT Coilinsonia canadensis (Labiatse), horse or ox-balm, citronella or rich- weed, a perennial aromatic herb growing in moist woods in the eastern and central portions of this country, furnishes the drug known as stone- root. Stoneroot is diuretic, alterative, and tonic to mucous tissues, and is employed in chronic catarrhal affections of the stomach and genital organs. It will be found in elixirs combined with Chondrodendron tormentosum, buchu, and juniper berries, and its presence may be suspected in any pro- prietary remedy intended to alleviate chronic ailments of the kidneys. It is a popular remedy for that condition of the larynx known as " Minis- ters' Sore Throat." The flowing top of the green fresh herb has a limited use. The extract of this portion of the plant has a characteristic lemon-like odor and a peculiar aromatic taste. SCUTELLARIA LATERIFLORA. SCULLCAP The perennial herb, Scutellaria lateriflora (Labiatse) is the official Scullcap. There are several other species of Scutellaria and some of them no doubt are occasionally mixed and sold with the official drug. The drug was formerly held in great repute as a remedy for hydro- phobia, but its use for this disease has been largely abandoned, and it is now employed as a tonic, nervine, and antispasmodic, and will be found in remedies for chorea, convulsions, tremors, intermittent fevers, neuralgia, delirium tremens, and nervous affections generally. It is combined with Cypripedium, hops, and Lactuca canadensis in fluid extract scullcap compound; with Viburnum opulus and skunk cab- bage in female nerve remedies of the " Viburnum Compound "type; and in tablets with lupulin, ergot, atropin, and zinc bromide. There is no research recorded, dealing with the chemistry of S. lateri- BOTANICAL DRUGS 443 flora. S. altissima, a foreign species, has been studied by Goldschmidt and Zerner, 1 and by Bargellini, 2 who worked on the composition and synthesis of scutellarin, a glucosidal body, which they extracted from the plant. Whether this glucoside exists in S. lateriflora has yet to be deter- mined. The researches of these chemists showed that scutellarin, C21H18O12, crj^stallized in yellow needles. When suspended in water, treated with concentrated sulphuric acid until it dissolved, and then poured into water, scutellarein, C15H10O6, was deposited and glucuronic acid remained in solution. When boiled with 25 per cent potassium hydroxide in a current of oxygen, para-hydroxyacetophenone resulted, and if hydrogen peroxide is added to the alkaline solution, para-hydroxyben- zoic acid is formed. Scutellarein on boiling with aqueous potassium hydroxide, gives para- hydroxyacetophenone and a substance resembling phloroglucinol in its color reaction with a pine splinter. Scutellarein gives the following colors on wool with the mordants mentioned; chromium, reddish brown; alumi- num brownish yellow; tin, lemon yellow; iron, olive green. In dilute alcohol glucuronic acid gives a green color when treated with alpha-naphthol and sulphuric acid; with more water the color changes through blue to violet and even to red. The green color is regenerated by concentrated sulphuric acid. The color reaction previously described for scutellarin is really a reaction for glucuronic acid. LEPTANDRA Leptandra or Culver's root is the rhizome and roots of Veronica vir- ginica (Scrophulariacese), a plant indigenous to North America. The drug has quite an extended medicinal use, and the crude resinous material obtained therefrom is one of the products to which the name " leptandrin" has been assigned. The term has also been applied to a glucosidal sub- stance reported as occurring in the root, but the existence of such a chemical individual is doubtful. Leptandra is also known as Bowman's root, tall speedwell, and tall veronica. The drug or its resinous constituents enter into a number of cathartic remedies and liver regulators, and usually will be found combined with Podophyllum resin. The cathartic pills and tablets consist of combi- nations of Leptandra with aloin, jalap, Podophyllum, gamboge, gentian, Capsicum, Hyoscj^amus, colocynth, and oil of peppermint. The liver combinations are of similar composition, but without Hyoscyamus and with the addition of calomel, Veratrum viride, and croton oil. Some special formulas contain juglans and Sanguinaria; Euonymus, creosote, chirata, and Iris versicolor; Leptandra is one of the constituents of the 1 Monatsch., 31, 439. 2 Gazz. chim. ital., 45, I, 69. 444 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS U. S. P. vegetable cathartic pills. It will be found in elixirs with Cascara sagrada, senna, juglans, and Rochelle salt, and in fluid extract mandrake compound with Podophyllum, senna, and jalap. Power and Rogerson 1 found that the root contained 6-7 per cent of a dark-brown resin, soluble in alcohol, from which they isolated a phytos- terol called verosterol, C27H46O, melting 135-136°, (a) D — 33.0°, a mix- ture of fatty acids (oleic, stearic, palmitic, and linolic), p-methoxycin- namic and 3 : 4-dimethoxycinnamic acids. The latter substance was also present in considerably larger quantity in an aqueous solution of the alco- holic extract of the drug, together with mannitol, a sugar yielding d-phenyl- glucosazone, melting 209-211°, tannin, coloring matter, and an intensely bitter amorphous substance. No glucosides were found, and the absence of saponin was established. The fact that an aqueous solution of 3 : 4-dimethoxycinnamic acid froths strongly on agitation, has doubtless led to the recorded statements of the presence of saponin in leptandra. The identification of Veronica virginica in medicinal mixtures by chemical means is not easy of accomplishment. The isolation of 3 : 4- dimethoxycinnamic acid would point strongly to the presence of the drug, but if " leptandrin," or the resinous portion were used alone, this acid would occur in minute quantity only, and probably would escape detec- tion. The isolation of verastrol from a mixture containing in all prob- ability other phytosterols, would be practically impossible. By centri- fuging a portion of the diluted alcoholic extract of the sample, any vege- table tissue present would be concentrated and by careful microscopic examination the characteristic feature of the drug might be detected. VERONICA OFFICINALIS The leaves and flowering tops of Veronica officinalis (Scrophulariaceae) the common speedwell or Paul's betony, are used in the form of an infusion for asthmatic troubles, coughs, and catarrh of the bladder. MITCHELLA REPENS. SQUAWVINE AND OTHER "SQUAW" DRUGS The original discovery of the efficacy of many drugs is often ascribed to the Indians, and this fact is featured in the literature of certain classes of proprietary remedies especially of the female regulator, spring tonic, and herbal compound type. For this reason there are several different drug plants to which the significant name of "Squaw " is attached, such as Squawvine, Squaw-weed, Squaw-root, etc. While there are probably several plants to which the name Squaw- vine is applied, the drug to which it belongs is Mitchella repens (Rubiacese), 1 Trans. Chem. Soc, 1910, 97, 1944. BOTANICAL DRUGS 445 the well-known partridge berry, a procumbent evergreen vine of our eastern woods. The entire aerial portion of the plant furnishes the drug. Mitchella repens is employed in dropsy, suppression of urine, diarrhea, and especially in deranged uterine conditions. Its presence may be sus- pected in any preparation, elixir, tablet, or ground mixed herb, called a female regulator, mother cordial, viburnum compound or squaw-weed compound. It is usually combined with Viburnum opulus (Cramp bark), Chamaelirium luteum (Helonias), Caulophyllum, Aletris farinosa (Star- grass) and Viburnum prunifolium (Black Haw). A survey of our North American botanical drugs shows the following list of common names suggestive of Indian origin: Squawhish. Viburnum opulus. Squaw flower. Trillium erectum (Wake-robin, birthroot). Squawmint. Hedeoma pulegioides (Pennyroyal). Squawroot. Applied to Caulophyllum thalictroides and Cimicifuga racemosa. (Blue and black cohoshes). Squaw-weed. Eupatorium ageratoides and several species of Senecio. Viburnum and the cohoshes have been given separate consideration. Senecio aureus (Composite), the Life-root or Swamp Squaw-weed, is the species of Senecio of importance medicinally. S. Robbinsii is called Robbins Squaw-weed; S. discoideus, Northern Squaw-weed; S. obovatus, Round leaf Squaw-weed; and S. Crawfordii, Crawford's Squaw-weed. S. Aureus is familiar to all in the early spring and summer as the golden ragwort, and is one of the earliest of the Composite to bloom. It is another of the numerous drugs which is supposed to have a special influence on the female reproductive organs and will be found in remedies for sup- pressed menstruation and other abnormal conditions of the uterine system. The herb and root furnish the drug. The flower resembles the arnica in some respects and the genus is closely related to the Arnicae. This plant has been reported as containing alkaloidal constituents, but its chemistry has never been carefully investigated. THE VIBURNUMS Several species of Viburnum (Caprjfoliaceae) have furnished drugs reputed of value in the treatment of asthmatic conditions, and for their uterine tonic and sedative effects. For a considerable period the identi- ties of the products sold on the market for true Viburnum, were in a confused state, and hence the descriptions credited to these drugs in the past must in some instances, be taken with reservation. There appear to be three species of Viburnum recognized as furnish- ing medicinal drugs. The cramp-bark is the bark of the indigenous shrub 446 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS V. opulus, which grows from New Jersey, Michigan, and Oregon north- ward. The drug known as V. prunifolium is the bark of the root of the black haw, and the bark of the root of V. lentago, the former occuring from Connecticut to Georgia west to Michigan, Kansas and Texas, and the latter having a range from Hudson Bay to Manitoba to New Jersey and along the AJleghenies to Georgia, westward to Indiana, Kansas, and Colorado. V. lentago is the sweet viburnum, sheep- or nanny-berry, V. prumfolium, the stag-bush or slow berry, and V. opulus, the highbush cranberry. For a number of years and until quite recently the drug sold as cramp bark was not derived from V. opulus at all, but from the mountain maple, Acer spicatum. The drug described in the seventh and eighth revisions of the U. S. P. as V. opulus applies to Acer spicatum. The National Formulary, fourth edition (1916), correctly describes V. opulus. The reason for the indiscriminate gathering of the barks of the high- bush cranberry and mountain maple, is apparent to one familiar with the growing plants. Mountain maple assumes the appearance of a shrub at one stage of its growth, and the structure of its leaves differs from the usual forms of the maples, and in the eyes of the ordinary drug collector might readily be mistaken for Viburnum. One may often see the moun- tain maple growing side by side with Viburnum, and this condition appar- ently obtains throughout the range of both species. V. opulus is a component of many of the mixtures recommended in female complaints of the uterine tract, and is combined with Chamselir- ium, Caulophyllum, Mitchella, Aletris, Scutellaria, skunk cabbage, and V. prunifolium. V. prumfolium is combined with the above-mentioned drugs and in other combinations with Hydrastis and Jamaica dogwood (Piscidia,) with Hydrastis, Jamaica dogwood, Cimicifuga, Cascara sagrada, Hyoscyamus, Cannabis sativa, and Potassium bromide ; with boric acid, potassium bicar- bonate, buchu, Triticum, corn silk, Hydrangea, and atropin; with celery, coca, and kola. These combinations may be found in liquid, tablet, and capsule form. Viehoever, Ewing, and Clevenger * report the results of a research made with a series of commercial specimens of cramp bark and black haw collected in 1915, and examined as to their identity. Of the fifty samples of cramp bark examined, forty-eight were derived from Acer spicatum. The specimens of the black haw were true to name. In 1916 they examined samples of Viburnum preparations in general on the market and found that those of V. prumfolium were true to label, while nearly all of those supposed to be made from V. opulus contained no Viburnum at all, but gave positive tests for maple. 1 J. Am. Pharm. Ass., 1918, (7) 944. BOTANICAL DRUGS 447 There is no difficulty in distinguishing between the Viburnum and Acer barks, both microscopically and chemically. The tannins of the former give a green color or precipitate with freshly prepared iron salts, whereas the tannin of the latter gives a blue precipitate or color. When worldng with the crude drug, a cross-section or a small quantity of the powder is treated with a drop of freshly prepared ferrous sulphate (1-1000), and the characteristic colors develop in a few minutes. Another distinguishing test for maple bark is the red lignin reaction obtained when a drop of phloroglucin-hydrochloric acid (phloroglucin 0.1 gram, alcohol, and concentrated hydrochloric acid 10 mils each) is applied to the inner side of the bark. Any wood fragments attached to the sample must be removed. The test is therefore applicable only in the case of the whole drug and not to ground samples. Viburnum barks yield but a faint reaction if any. When the above described reaction is carried out on Viburnum specimens, the odor of valerianic acid will develop. Acer barks do not yield this acid. To distinguish between maple and Viburnum tannins in pharmaceu- tical preparations containing alcohol, about 10 mils are diluted with three volumes of water and shaken out with 15 mils of ether. The ethereal layer is filtered and shaken in a test-tube with an equal volume of water containing two drops of freshly prepared saturated ferrous sulphate solu- tion. A green color in the lower layer indicates a Viburnum species, a blue color indicates a maple. A confirmatory test for the Viburnum species should be made by separating and identifying valerianic acid. If the sample is a fluid extract 10 mils should be made alkaline with sodium hydroxide and boiled to expel the alcohol; if a mixed pharmaceutical is under examination, a larger quantity should be neutralized with sodium bicarbonate and evaporated to expel the alcohol. The alcohol free mixture is then acidified with sul- phuric acid, distilled with steam, and the presence of valerianic sought in the distillate. The acid may be separated from the distillate, by satu- rating with salt, shaking out with ether, transferring the ethereal solution and removing the solvent over the steam-bath. Viehoever and his coworkers identified valerianic acid by its boiling-point and by the char- acteristic microchemical forms of the copper, zinc, and mercury salts. The zinc compound prepared with zinc nitrate was the easiest to obtain. VALERIANA OFFICINALIS The rhizome and root of Valeriana officinalis (Valerianacese), the com- mon valerian, is used as a stimulant to the nervous system, and is a com- ponent of medicines used in hysteria, hypochondria, restlessness, and other nervous disorders. Valerian is combined with Hyoscyamus and camphor; 448 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS with phosphorus and zinc salts; with Hyoscyamus, musk root (Sumbul), and Cannabis sativa; with coca, codein, Cannabis sativa, strychnin, arsenous acid, and ferrous carbonate; with Sumbul and asafetida; with Sumbul, asafetida, ferrous sulphate, and arsenous acid, etc. These seda- tive mixtures are usually dispensed in the form of pills and tablets, and are often sold at a high price with great claims as to their virtue in restoring normal sexual functions or for controlling abnormal condi- tions. The valerianates prepared from valerianic acid are often present in sedative mixtures, and these products as well as the description of valerianic acid have been discussed in the section of Pure Organic Bodies. The characteristic constituent of the valerian root is the oil which amounts to about 1 per cent, and which contains, among other constitu- ents, the valerianate of borneol. This ester gradually hydrolyzes, and hence the root and the extract have the odor of valerianic acid. The root of Valeriana mexicana yields an oil containing free valerianic acid, and Japanese valerian, which is probably a variety of V. officinalis, yields an oil which closely resembles the oil of the official drug, but which con- tains the acetate of an alcohol having the composition, C14H24O2, and termed kersyl alcohol. The latter substance crystallizes in large well- formed crystals, melting 85°. It is odorless, insoluble in water, readily soluble in organic solvents, boils 155-156° under 11 mm. pressure, and is laevogyrate. The odor of valerianic acid is apparent in examining other drugs and their extracts, notably the Viburnum, Angelica, Sambucus species, etc., hence it is necessary to use caution in diagnosing the presence of V. offici- nalis. Oil of valerian is a yellowish-green to brownish-yellow liquid, slightly acid, with a penetrating and characteristic and not unpleasant odor. Old oil is dark brown and viscid, with a strongly acid reaction due to the presence of free valerianic, formic, acetic, and butyric acids, often with considerable separated borneol, and having a disagreeable odor. The normal gravity is between .93-96, (a) D =— 8 to —13°, acid number 20-50, ester number 80-100, and saponification number 100-150. BRYONY ROOT The drug known as bryony root is yielded by the plants Bryonia alba and B. dioica (Cucurbitacese) . Both of these plants are natives of Europe, but the latter is the species commonly found in England, and is fre- quently designated English bryony. The roots of both species are consid- ered by some authorities as possessing the same properties, and they appear to be collected and sold as bryony without regard to their botanical individuality. The roots of B. americana and B. africana are respec- tively used in the West Indies and Africa in cases of dropsy. BOTANICAL DRUGS 449 Bryony root is an hydrogogue cathartic, and is chiefly employed in dropsy. It is also prescribed to a limited extent in chronic intermittent fever, enlargement of the spleen, chronic bronchitis, and catarrhal whoop- ing cough. It is usually dispensed in the form of tablet triturates and coated tablets. Bronchitis mixtures contain in addition to bryony, aco- nite, belladonna, tartar emetic, and potassium bichromate; fever com- binations include aconite and belladonna; and cold and fever mixtures contain aconite, Eupatorium perfoliatum, Gelsemium, and camphor, monobromate; tonsillitis compounds consist of aconite, belladona, and mercuric iodide, often with the addition of morphin and salicylates. For dropsical conditions the fluid extract or a tablet of the tincture are employed. Power and Moore * examined B. dioica chemically. An enzyme was found which hydrolyzed a glucosidic constituent of the root, and also acted on amygdalin and salicin. An alcoholic extract of the root yielded 2 per cent of a resin and a water soluble portion which contained a colorless, crystalline, neutral substance, C20H30O5, melting 220-222°, slightly soluble in ether and when purified, almost insoluble in ether, but dissolving readily in alcohol. The water-soluble portion also yielded a glucoside, an amor- phous alkaloid and a sugar which formed a d-phenylglucosone, melting 208-210°. The glucoside was soluble in amyl alcohol and ethyl acetate, bitter, precipitated from aqueous solution by tannin, and giving no color with ferric chloride. On hydrolysis with dilute sulphuric acid, it gave a brown resin and a sugar whose c/-phenylglucosone melted 208-210°. The alkaloid was intensely bitter, soluble in water and alcohol, but spar- ingly in ether and chloroform, and was precipitated by the usual alkaloidal reagents and tannin. Ammonia was evolved on heating with alkali hydroxide, and hydrochloric acid decomposed it with the formation of ammonium salt. The resin was dark brown, viscous, and completely soluble in ether. From it were isolated a phytosterol, C27H46O, melting 137° and optically inactive; bryonol, melting 210-212°, and a mixture of oleic, linolic, pal- mitic, and stearic acids. Bryonol belongs to the group of substances which Power and Salway have since concluded are phytosterol glucosides. Its solution in chloroform gave with acetic anhydride a series of color reac- tions similar to those produced by ipurganol, a purplish pink, changing to blue, green, and brown, and it dissolved in concentrated sulphuric acid with a yellow color, the solution showing a green fluorescence. It is closely allied to cucurbitol, a substance isolated from the resin of watermelon seed. The substance obtained from bryony root b} r precipitation with tannin, and designated " bryonin " by previous investigators, is evidently a com- plex mixture. 1 Trans. Chem. Soc, 1911, 99, 937. 450 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS PUMPKIN SEED The seeds of the common pumpkin, Cucurbita pepo (Cucurbitaceas), have attained considerable reputation for their taenicidal properties. The fluid extract is used for expelling tape-worm and in combination with Cascara, senna, Rochelle salt, Chenopodium, and sodium bicarbonate it is prescribed as a children's remedy. Power and Salway 1 determined that the seeds contained about 34-35 per cent of a fixed oil removable by petroleum ether, consisting of the glycerides of linolic, oleic, palmitic, and stearic acids; a resin amounting to about 0.5 per cent; a small amount of salicylic acid; soluble proteins, sugar, and starch. Neither the oil nor the resin was found to effect the complete removal of tape-worm which was administered under the usual conditions of fasting and followed by a dose of castor oil. TARAXACUM The root of the well-known dandelion, Taraxacum officinale syn. T. taraxacum (Cichoriacese) , is a popular tonic and alterative. It is chiefly employed in derangements of the liver, in dyspepsia, in cutaneous erup- tion due to a disordered liver, and of late has been prescribed as an adjunct to the treatment of cancer. It is combined with senna; with Podophyllum and Conium; and with Sarsaparilla; with licorice and wild cherry; with licorice, gentian, verba santa, and Eucalyptus, etc., in liquid extracts and elixirs. In pills and tablets extract of Taraxacum is combined with quinin, arsenous acid, and iron; with podophyllum resin, Capsicum, Euonymus, Apocynum and balmony; with Nux Vomica, coiocynth comp., quinin, oxgall, and pancreatin and other similar combinations. Powered Taraxacum occurs mixed with Asclepias tuberosa, Ginger, Capsicum, Angelica, and Bayberry bark in a mixture designed as a secret remedy for intoxication and the drink habit. The plant grows all over the United States, but the drug is chiefly imported from Europe. Dandelion root contains considerable inulin and a laevorotatory sugar which appears to be mostly lsevulose. Power and Browning 2 found that an alcoholic extract of the drug yielded a resin and certain water-soluble substances, including/ p-hydroxy-phenylacetic acid, melting 144-146°; 3j_4__ dihydroxycinnamic acid, and cholin, C5H15NO2. The resin amounted tcTT.8 per cent of the weight of the dried root and yielded a monohydric alcohol, taraxasterol, C29H47OH, melting 221-222°, (gO.d+96.3 ; a mono- hydroalcohol homotaraxasterol, C25H39OH, melting 163-164°, (a)z>+25.3°; 1 Journal Amer. Chem. Soc, 1910, 32, 346. 2 Trans. Chem. Soc, 101, 1912, 2411. BOTANICAL DRUGS 451 cluytianol, C29H460(OH)4 melting 297° (a phytosterolglucoside) ; palmitic, cerotic ancf melissic acids, together with a mixture of unsaturated acids, consisting chiefly of oleic and linolic, with apparently a little linolenic acid. An extract of Taraxacum root when extracted with Prolius mixture yields a trace of material giving a precipitate with Mayer's reagent. The alkaloid cholin probably furnishes the best indication of the pres- ence of the drug in medicinal mixtures. If an alcoholic extract is evapo- rated and treated with water, the cholin will go into the aqueous liquid. After precipitating with basic lead acetate, filtering, and removing the excess of lead with hydrogen sulphide, the filtrate on evaporation may be concentrated to a thick syrup, extracted with alcohol, filtered, the alcoholic solution concentrated and the treatment with alcohol repeated until no insoluble material remains. The alcoholic solution is then treated with a saturated solution of mercuric chloride in alcohol and allowed to stand several days. The precipitated cholin compound is then filtered, washed with alcohol, and dissolved as completely as possible in water, from which the mercury is precipitated with hydrogen sulphide. The filtered liquid, is neutralized with sodium carbonate, slightly acidified with hydrochloric acid, and evaporated to dryness in a vacuum desiccator. The dry residue is treated with absolute alcohol, filtered, evaporated, and the treatment with absolute alcohol continued until the inorganic salt is eliminated. The final product will be deliquescent and its aqueous solution gives a yellow precipitate with gold chloride. Its solution in absolute alcohol will give a precipitate with platinic chloride, which if dissolved in a little water will finally deposit in the form of reddish-brown plates, melt- ing with decomposition at 250-254°. It is probable that cholin is the substance to which the name " tar- axacin " was given by investigators who have, at one time and another, attempted to determine the constituents of Taraxacum. BURDOCK. ARCTIUM LAPPA Burdock root is a popular alterative. Its extract is employed in remedies intended for gout, rheumatism, leprosy, and similar diseases. It usually occurs in admixture with other drugs, especially Stillingia, Phytolacca, Xanthoxylum, red clover, and Iris. Mixtures of the Succus Alterans or Alterative compound type consist of bamboo-brier root, bur- dock, Xanthoxylum, Stillingia, and Phytolacca; those of the Trifolium compound order contain red clover, burdock, Berberis aquifolium, Xan- thoxylum, Stillingia, Phytolacca, Cascara amagra, and potassium iodide. These preparations are offered in the form of extracts, syrups, pills, and tablets. Sassafras is often present in syrups of burdock root. 452 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The seed is used as a tonic and alterative and has been used success- fully in skin diseases, such as psoriasis. The fresh leaves have also a limited use. The roots of other species of Arctium are also uaed and are recognized in the U. S. Pharmacopoeia. It is directed that the drug be collected from plants of the first year's growth. The flowers are not produced until the second year. Very little work has been done on burdock root, but it apparently contains a sugar, inulin, and a fixed oil. GRINDELIA SPECIES. GUM PLANT OR TAR-WEED There are some thirty species of Grindelia (Composite) native of western North America, Peru, and Chile. About seventeen species occur in the western and southwestern parts of North America, G. squarrosa and G. lanceolata extending their range also east of the Mississippi. G. squarrosa occurs over a wide area, being found in dry soil in Illinois and Minnesota to Manitoba, Missouri, Texas, Arizona, and Mexico, and adventive in southern New Jersey, Pennsylvania, and New York. The plants furnishing the drug are commonly designated as the above and G. robusta, but it is probable that the botanical identities of the commercial products have been confused with other species. G. robusta is a somewhat rare plant and according to Perredes * occurs much too sparingly to be a factor of any importance in the consideration of the drug on the market. G. squarrosa appears to occur to a limited extent in Calif ornia, from which State a large part of the commercial drug is obtained. G. camporum occurs abundantly in the inner coast ranges, in the foot- hills of the Sierra Nevada, and is almost the only plant found on the plains in certain regions of the Sacramento Valley. G. cuneifolia is the next most abundant species in California; but G. camporum is the common " gum plant " of California. It is stated that when collectors are asked to furnish separately " Grindelia squarrosa " and " Grindelia robusta," the plant growing in the marshes (G. cuneifolia and its variety paludosa) is supplied for the latter, while G. camporum, the plant of the dry hills and plains is sup- plied for the former. The drug commonly occurring on the market is now probably largely G. camporum. Grindelia is used in the treatment of asthma, bronchial troubles, pertussis, catarrh of the bladder, and other diseases of the mucous mem- brane of the genito-urinary organs. Locally its tincture or fluid extract 1 Proc. A. Pha. A., 1906, 54, 370. BOTANICAL DRUGS 453 has proven of value in ivy poisoning. Fluid extract Grindelia compound contains senna and rhubarb. Bronchial mixtures will contain Grindelia, Eriodictyon, licorice, tar, wild cherry, salicylic acid, and potassium bromide in syrupy or glycerin menstruums. Expectorant tablets contain senega, Grindelia, aconite, squill, guaiac, ammonium bromide, and car- bonate. Alkaline extracts of the drug are commonly sold for admixture with syrup without precipitation of the resin. Power and Tutin 1 found that G. camporum contained 21-22 per cent of a complex resin to which its medicinal value is probably due. This resin was partly soluble in petroleum ether, and the portion remaining undissolved was nearly all taken up by ether, the first fraction being a soft, sticky, greenish mass, and the second a dark-colored resin. That portion of the Grindelia resins which were soluble in petroleum ether consisted to a large extent of a complex mixture of liquid acids, which were for the most part optically active, unsaturated cyclic com- pounds, some being oxyacids with apparently benzene nuclei. A very small amount of cerotic acid and apparently a trace of palmitic acid were present. A considerable quantity of chlorophyll was also present. The non-acidic portion of this fraction contained hentriacontane, C31H64, melting 68°, a new phytosterol, melting 166°, giving with sulphuric acid in a solution of chloroform and acetic anhydride, a rose color changing to violet, blue, dark green, and finally brown. It consisted, however, for the most part of a complex mixture of esters, presumably glycerides, the acids of which appeared to be similar to those which were present in the free state. The ether extract of the resin consisted to a very large extent of a mixture of amorphous products, but there were also present very small amounts of grindelol, a colorless crystalline substance, C23H38O4, melting 256-257°, probably a phytosterol glucoside, and a yellow phenolic sub- stance, C14H12O5, melting 227-228°. That portion of the total resin insoluble in petroleum ether and ether amount to about 8 per cent and was nearly all dissolved by alcohol. An aqueous solution of an evaporated alcoholic extract of the drug contained free formic and butyric acids, tannin-like substances, ^-glucose, and protein. It gave precipitates with both neutral and basic lead acetates. No alkaloids nor saponins were detected. The characteristic odor of Grindelia is due to a volatile oil, and the presence of this ingredient is about the only distinguishing feature of the drug which can be used for its identification in complex mixtures. This evidence, backed by the identification of the readily detectable formic acid and the presence of a dark-green resin, may be considered as proof of the presence of the drug. 1 Proc. A. Pha. A., 1905, 53, 193, and 1907. 454 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS ECHINACEA The root of the purple cone-flower has been recommended as an alter- ative and aphrodisiac, and may occur in preparations used for purifying the blood and for toning up the system. It also occurs in remedies intended to reduce swellings, varicose veins and abnormal growths. The freshly scraped root has been employed in the treatment of snake bites. Echinacea angustifolia (Brauneria a.) Composite, the narrow-leaved purple cone-flower is usually considered the source of the drug, but it is probable that the roots of E. purpurea, the purple cone-flower or black sampson, and E. pallida, the pale purple cone-flower, are collected and solid for the official drug without qualification. It is reported that large quantities of the root of Parthenium integri- folium, prairie dock or American fever-few, have been on the market at various times, apparently intended as a substitute for or adulterant of Echinacea. Heyl and Staley x report the following proximate analyses of angusti- folia and purpurea. E. angustifolia Per Cent E. -purpurea Moisture 10.90 10. 18 Starch absent absent Pentosans 15 . 6, 15 . 1 15.6 Fiber 24.77, 24.46 29.65, 29.51 Protein 6.54, 6.96 5.31, 5.17 Ash 7.76 .6.93 Inulin 5.9 not determined Inuloid substance 5 . 94, 6 . 14 916 Yield of Extract with: Ligroin 0.77 ■'. . . .0.93 Ether 1 . 26, 1 . 18 1.61 Alcohol 19.7, 19.94 18.28 Examination of Alcohol Extract: Resin 1.84 2.00 Sucrose 6.92 3.40 Reducing Sugars 3.65, 3.52, 3.89 3.41 Volatile Oil 0.04 No alkaloid sufficiently basic to be extracted by the ordinary methods - is present, but the possibility of cholin or allied substances is not excluded. ARNICA MONTANA The flowers and the root of Arnica montana (Compositae) are used medicinally, and a tincture of the flowers is the preparation in common use externally for the relief of pain from bruises, sprains, etc. 1 Am. J. Pharm., 86, 450. BOTANICAL DRUGS 455 Arnica flowers are frequently adulterated and substituted by those of Calendula officinalis, Inula species, and Tragopogon pratensis. CALENDULA OFFICINALIS. MARIGOLD The ligulate florets of Calendula officinalis (Composite) are used for the same purposes as Arnica, and especially as a local remedy after surgical operations. As an internal remedy the drug has little use at present, though it was formerly used as a stimulant and diaphoretic. It will be found in certain popular local remedies intended to allay inflammation and reduce swellings, where it is mixed with Artemisia absinthium, Echi- nacea angustifolia, menthol, oils of lavender, sassafras, etc. Calendula contains a volatile oil and a gum which forms a transparent white mucilage with water, not precipitated by tannin. CARTHAMUS TINCTORIUS. SAFFLOWER Safflower or American saffron consists of the dried florets of Carthamus tinctorius (Compositse) . As a drug it was formerly employed for the same purposes as Calendula, especially to promote efflorescence in measles and other exanthemata, as a diaphoretic, and to dissipate incipient catarrh and muscular rheumatism. It is used to some extent as a component of emmenagogue mixtures with aloes, rue, and savine. THE CONDIMENTAL DRUGS There are several highly flavored vegetable products which are esteemed as flavoring agents in different classes of foods and have also an extended use in the compounding of medicines, where they functionate as flavor- ing agents, aromatics, or carminatives. Anise Anise seed, the fruit of Pimpinella anisum (Umbelliferse) is used as a carminative, for increasing the secretions of the mammary glands, and as a flavoring agent, in several well-known remedies and official mixtures. Both the ground fruit and the oil are used. The whole fruit is an important article of commerce, and it is often adulterated with small pebbles, earthy particles specially manufactured for the purpose, the fruits of grasses and rushes, and the fruit of Conium maculatum. The pebbles are easily detected by sprinkling a handful of the sample on the surface of water contained in a large beaker and rapping the sides of the container, when the heavier particles will sink to the bottom. Conium may be detected microscopically, by the mousy odor developed on warming with caustic alkali, and by the examination of an alcoholic extract of the drug for alkaloids. The ash of pure anise amounts to 7- 10 per cent. The oil runs from 1.5-6 per cent. 456 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Oil of anise enters into the composition of many different formulae. Liquid camphor compound contains anise oil, opium, camphor, and ben- zoic acid; liquid preparations of seneca and Spigelia sometimes contain oil of anise; and it is also present with rhubarb, licorice, and cardamon; and in the sarsaparilla mixtures with sarsaparilla, senna, potassium iodide, licorice, sassafras, and methyl salicylate. Fluid extract of orange com- pound contains extract of anise seed, orange peel, cloves, caraway, orris root, mace, cinnamon, and tonka. Oil of anise is present in cough lozenges and tablets, liver pills and infants' corrective tablets. Fennel Fennel fruit, from Fceniculum vulgare (Umbelliferae) and from the variety dulce (sweet or Roman fennel), is a carminative and aromatic drug, and used chiefly as a corrigent of senna, rhubarb, and other unpleas- ant tasting drugs. Fennel contains from 2-6.5 per cent of volatile oil, about 12 per cent of fixed oil, calcium oxalate and 7 per cent ash. The volatile oil contains 50-60 per cent of anethol, 20 per cent fenchone, chavicol (an isomer of anethol), anise ketone, anisic aldehyde, anisic acid, d-pinene, and dipen- tine. The oil from sweet fennel contains no fenchone. Macedonian oil contains limonene, and phellandrene but no fenchone. The drug is adulterated with wheat screenings, undeveloped fruits, and various other umbelliferous fruits and dirt. The sophistications are detected microscopically and by the other tests given under anise. Oil of fennel is combined with opium and sodium bicarbonate in remedies for the colic of infants. The extract of the seed is one of the components of Warburg tincture. Caraway The fruit of Carum carvi (Umbelliferae) has an extended use as a flavoring agent, and medicinally as a remedy for the flatulent colic of infants. The most prominent constituent of the drug is the oil, which amounts to 5-7 per cent, and consists of about equal parts of d-carvone and d- limonene. The ash runs from 5-8 per cent. Calcium oxalate is a con- stant constituent of the fruit. Black caraway is the name given to the fruit of two plants belong- ing to an entirely different family, Nigella sativa and N. damascena (Ranunculaceae) . These seeds contain alkaloidal constituents and a volatile oil with a flavor like the wild strawberry. Caraway oil is one of the ingredients of fluid extract cardamom com- pound and of Spigelia and senna compound. It is also a component of BOTANICAL DRUGS 457 certain pill formulae with aloes, soap, and confection of roses; rhubarb, colocynth, and Hyoscyamus; gentian, aloes, and rhubarb; aloes, scam- mony, myrrh, croton oil, and mercury mass. Coriander Coriander fruit from Coriandrum sativum (Umbellif erae) , is used medicinally as a stimulant and carminative. The chief use of the fruit is for the preparation of oil of coriander which is an important flavoring agent. Of the constituents, the most important is the oil, which amounts to 0.5-1 per cent and has a characteristic odor. The normal ash is about 5 per cent. Calcium oxalate is present. Extract of coriander will be found combined with Stillingia, Chima- phila, Iris versicolor, Bicuculla, Sambucus, and Xanthoxylum berries in syrups and elixirs. It is also combined with senna, jalap, and rhubarb. Pimento Allspice or pimento is the fruit of Pimento officinalis (Myrtacese). While it is principally used as a condiment, it occurs in medicinal com- pounds as a stomachic, stimulant, and carminative. It is combined with pepsin, gentian, ginger, cardamom, and cinchona alkaloids. The fruit contains 3-4 per cent of a volatile oil, which consists of about 60 per cent of eugenol. The ash runs from 4-7 per cent, but according to the standards of the Association of State and National Food and Dairy Departments it should not run over 6 per cent, with not more than 0.5 per cent insoluble in hydrochloric acid. According to the same authorities the crude fiber should run not over 25 per cent, and the quercitannic acid not less than 8 per cent, calculated from the total oxygen absorbed by the aqueous extract. It should be mentioned at this point that determi- nations of tannins based on the absorption of oxygen are of little value in arriving at a conclusion as to the actual quantity of tannin-like substances present. The most common adulterants of powered allspice are cocoanut shells and cereal starches; other substances reported include clove stems, peas, olive stones, turmeric, pepper, Capsicum, and exhausted ginger. Tobasco or Mexican allspice is yielded by a variety of P. officinalis; Crown allspice by P. acris. Cloves Cloves are the dry undeveloped flowers of Caryophyllus aromaticus (Myrtacese), and in the ground state are used for condimental purposes, and in a small way medicinally for their stimulant and antispasmodic effect. The oil of clove is used as a flavoring, a corrective of griping purgatives, and in toothache remedies. 458 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Volatile clove oil, which is the valuable constituent of the flowers, con- sists of about 70 per cent of eugenol with a smaller quantity of the sesqui- terpene caryophyllene. The oil runs from 9-20 per cent. The total ash ought not to be over 8 per cent, the crude fiber 10 per cent, and the food standards of the state officials demand not less than 12 per cent querci- tannic acid, determined by the empirical oxygen absorbed method. Ground cloves are subject to adulteration with clove stems, allspice, starch, exhausted ginger, and the other adulterants common to ground spices. Oil of cloves is combined with blackberry root bark and cassia and with rhubarb, cassia, and nutmeg. Powdered cloves is one of the ingredi- ents of blackberry cordial, which contains in addition nutmeg and cin- namon. The oil occurs with colocynth, aloes, scammony, and potassium sulphate; with strychnin, pepper, ipecac, and gentian; with aloes, Nux Vomica and Podophyllum resin, and similar combinations in pill formulae. Cardamom The fruit of Elettaria cardamomum (Zingiberacese), with its peculiar and characteristic flavor, is added to tonic and stimulant preparations chiefly as a flavoring agent. The commercial varieties are known as Malabar and Mysore cardamoms. The drug contains 4-5 per cent of volatile oil and from 4-6 per cent ash. Fluid Cardamom compound contains cardamom, caraway, cassia, and cochineal, and the British formula contains extract of raisin. Cardamom occurs in liquid aloes compound with myrrh, licorice, potassium carbonate, and saffron; in liquid cinchona, rhubarb, and gentian mixtures. Powdered cardamom is one of the ingredients of the compound cathartic vegetable pills and tablets with colocynth, Podophyllum resin, soap, scammony, and aloes; it occurs with gentian, ginger, Pimento, pepsin, and cinchona alkaloids; and with Capsicum and sodium salicylate. Cassia and Cinnamon The terms cassia and cinnamon are interchangeable commercially, but strictly speaking cinnamon is the inner bark of Cinnamonum zeylan- icum (Lauracese) of Ceylon, Sumatra, Java, and tropical Asia, or of C. louriria (Saigon cinnamon), and cassia is the bark of C. cassia, which comes from China, Indo-China and India. Cassia buds are the dry flower buds of the China cassia. Powered cassia often consists of a mix- ture of several varieties of bark, and the cheaper grades sometimes con- tain an admixture of the ground buds. While these products are of economic importance principally as condi- BOTANICAL DRUGS 459 ments, they have a limited use medicinally as astringents and for their aromatic and flavoring properties. The ash of the Cinnamonum species should not be over 6.2 per cent. The important constituent is the volatile oil, which runs from 0.5-1 per cent in the Ceylon cinnamon and from .5-3 per cent in the cassia. The oil is composed principally of cinnamic aldehyde. Mannitol is present in the bark. The powdered drug may be adulterated with the usual spice adulter- ants, and in addition one may meet with the barks of other trees and epecially those species of Cinnamonium void of aromatic properties. Batavia cassia or Fagot cassia is the bark of C. burmanii. Powdered cinnamon is one of the ingredients of aromatic chalk powder, which also contains saffron, nutmeg, cloves, cardamom, and calcium car- bonate. The oil and the extract of cinnamon is often found combined with rhubarb and blackberry in liquid preparations. It occurs with aloes and iron sulphate in pills, and with methylene blue, salol, and sandalwood oil in soluble elastic capsules. CHAPTER XIV GUMS AND RESINS Gums and resins have played an important part in medicine since the early ages. To-day many of them are still used to a large extent for their therapeutic value and others are indispensable as mechanical agents. Whether used for the one purpose or the other their recognition is generally important. Gums such as acacia and tragacanth are often employed as emulsifying agents; rubber and colophony furnish the bases of plasters, and the chemist analyzing such preparations with a view to duplication must needs identify the kind and determine, at least approxi- mately, the amount of the mechanical agent present. Nearly all vege- table extracts contain more or less resin or gum, but the resins and gums of a comparatively few species have been described and their character determined. Those that have been investigated are generally extracted from the plant previously to their incorporation into medicine, and there- fore they are themselves commercial units, and as such are often the identi- fying features of the plants. Commercial gums and resins in the powdered form are subject to more or less adulteration and substitution. Standards have been adopted for most of the products recognized by the trade, and of late considerable attention has been directed toward the evolution of reliable tests for determining their quality. Gums and resins are very different chemically, but they are conven- iently considered under one heading and they are very often associated, the one class with the other. Gums belong to a class of complex poly- saccharide glucosides, while resins are composed of esters of aromatic acids with alcohols or resinotannols, resin acids, and indifferent bodies known as resenes. Gums are soluble in or swell up in contact with water and are not dissolved by alcohol. Resins are insoluble or but slightly dissolved in water; most of them are soluble or partly so in alcohol and ether. The resin esters are saponifiable. Naturally occurring mechanical mixtures of gums, resins, and volatile oils are classed as gum resins, oleo- resins, and balsams. Gum resins consist of variable mixtures of gums and resins, often with the presence of volatile oils (aromatic gum resins). Oleo-resins consist of resins and volatile oils, the former frequently being dissolved in the latter. Balsams consist of resins, aromatic acids, alco- 460 GUMS AND RESINS 461 hols, and esters. The terms " gum," " resin," and "balsam " are often applied incorrectly from a chemist's standpoint. Trade customs over many years have brought about this condition, and the confusion of the commercial designation with the true chemical facts will often prove disconcerting to the analyst. CLASSIFICATION OF GUMS AND RESINS Gums Acacia. Soluble in water and precipitated by alcohol. Irish Moss and Quince Seed Gum. Soluble in water but not precipitated by alcohol. Agar. Soluble in water and partly precipitated by alcohol. Tragacanth. Swelling up with water and a portion dissolving. Indian Gum. Swelling up with water, but not dissolving, yielding acetic acid on hydrolysis with phosphoric acid. Resinous Substances (Lewton) True Resins Copal Group. Insoluble in the usual solvents unless themselves previ- ously fused. Dammar Group. More or less soluble in ether, chloroform, benzol, and acetone, but insoluble in alcohol. Sandarach Group. More or less soluble in alcohol. Guaiacum belongs to this group. Colophony Group. Soluble in alcohol. Benzoin Group. Soluble in alcohol, liberates benzoic or cinnamic acid when heated. Shellac Group. Form a turbid solution in alcohol. Gum Resins Inodorous Gum Resins. Yield an emulsion with water. Gamboge belongs to this group. Aromatic Gum Resins. Contain ethereal oils and yield an emulsion with water. Asafetida Group. Comprises asafetida, galbanum, ammoniacum, and opopanax. Myrrh Group. Myrrh, dibanum, and bdellium. Oleo-resins Varnish Group. Copaiba Group. Liquids. Turpentine Groyp. Soft resins, containing larger or smaller quantities of volatile oils. 462 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Elemi Group. Soft resins rarely containing more than 10 per cent of ethereal oil. True Balsams Peru balsam, Tolu balsam, and liquid storax. GUMS Gums are chemically closely related to the glucosides. O'Sullivan has shown that they are built up of the residues of sugar molecules united by ethereal oxygen to organic acids. The sugars commonly evolved on hydrolysis are galactose and arabinose, but the acids usually differ in different gums, acacia containing arabic acid and tragacanth bassoric acid. Gums are soluble in, or swell up in contact with water, and are not dissolved by alcohol. They are amorphous, non-volatile, and colloidal. They are not fermentable by yeast. Their solutions are usually laevo- rotatory, but this is not. always the case, as Australian acacia is inactive, and gedda gum is dextro. They yield mucic acid on treatment with nitric acid. Natural gums are often admixture's of several gum compounds differ- ing in the number of sugar residues in their molecules. The testing of the gum components of complex mixtures is greatly complicated by the uncertain knowledge of the chemistry of gums and because of the sub- stitution and admixture of one gum with another, often through the ignorance of the crude drug merchant. The trade in powdered gums is large, and opportunities for sophistication are great and often resorted to. These conditions have been the cause of many erroneous reports concerning the chemical reactions and tests of gums. Tests for the pres- ence of tragacanth in ice cream have been worked out on Indian gum of an entirely different composition and properties than tragacanth. Mixtures of Indian gum and acacia have been sold for the pure acacia and used for the same purposes as the pure gum without detection on the part of the user. It is only within the last few years that tests have been devised for successfully proving the admixture of one gum with another. Those tests have been adapted to powdered gums as commercial commodities and not to mixed gums in pharmaceutical com- binations such as pills and emulsions. While it is possible to detect an individual gum in a pharmaceutical combination, it is doubtful if one would be justified in attempting to differentiate between several gums when together in such combination unless perhaps the component gums were equally balanced in amount. In such cases the personal experience of the investigator, resulting from the actual knowledge of how authentic gum specimens react, is of greater aid than printed directions. GUMS AND RESINS 463 Acacia Gum (Gum Arabic) Several species of Acacia (Leguminosse) yield gums consisting prob- ably of calcium arabate and arabic acid. The gums of the best commercial qualities are designated gum arabic or gum acacia, those of less commercial value are the Senegal gums. Extensive researches on the sources, chemistry, and economic impor- tance of the Acacia gums have been conducted by the Wellcome Research Laboratories, Gordon Memorial College, Khartoum. The chief gum exported from the Sudan is that obtained in the Kordofan Province from the Acacia verek ('hashab), said to be identical with the Acacia Senegal from which Senegal gum is derived. As it ordinarily appears in commerce gum arabic occurs in rounded or ovoid tears or broken angular fragments. The color varies from white or yellowish white to amber. The pieces are usually translucent, but some of the angular fragments are often nearly transparent. When first collected the pieces are transparent and glassy, but. on exposure to the sun or artificial heat they dry and crack, the cracked pieces being nearly snow-white in color and very friable. Senegal gum is exposed to a less intense heat, and the gum itself is less brittle, consequently fewer cracked pieces and broken fragments are produced. The ash of good gum does not amount to over 4 per cent. The use of these gums for purely medicinal purposes is decidedly limited, being confined to soothing lotions and demulcents. They are important adjuncts in the preparation of pills, compressed tablets, troches, certain kinds of lozenges, and emulsions. The identification of gum acacia is not difficult. Its quantitative determination is seldom more than approximate. The value of a quanti- tative determination depends somewhat on the case in hand. If it is a question of accounting for the composition or of closely duplicating a given preparation it is important to know the kind and approximate amount of the gum present. Gum acacia is soluble in water to a clear liquid but is insoluble in alcohol and other organic solvents and the addition of alcohol to an aqueous solution of the gum precipitates the latter, when the alcohol amounts to 50-60 per cent. Tragacanth mixes with water to a pasty mass and a portion dissolves, but the appearance of the mixture is in no way comparable to that of acacia. Indian gum simply swells up with water to a transparent jelly. If the water is in large amount the mixture appears to be a solution, but it is not. When a 2 per cent solution of gum acacia is treated with 2J times its volume of 50 per cent alcohol and a 25 per cent solution of ferric chloride (acid free) is added a precipitate is produced. The deposit is often slow in forming. 464 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Basic lead acetate solution throws out gum arabic as a curdy pre- cipitate. Neutral lead acetate does not produce a precipitate with solu- tions of the gums usually found in commerce. Copper sulphate followed by an excess of sodium hydroxide produces a precipitate which rises to the surface and does not dissolve on warming. Dextrin yields a precipitate which dissolves on warming, and the copper is reduced on boiling; however, nearly all samples of acacia have a vari- able cupric reducing action. The gum can be regenerated by dissolving the copper compound in dilute hydrochloric acid and adding alcohol to throw out the gum. These tests can be applied directly to a 2 per cent solution of the gum. When working with pharmaceutical mixtures it is advisable to separate the gum from the bulk of the material by digesting the material with water, filtering, and precipitating with an excess of alcohol. The precipitated gum can then be brought on to a filter, washed and dried, and then redis- solved in water to a 2 per cent solution. Emulsions should be mixed with a considerable volume of petroleum ether and then sufficient alcohol added to produce approximately a 50 per cent aqueous menstruum beneath the volatile solvent when this sepa- rates. By separating the fight solvent which contains most of the oil and treating again, practically all of the oil can be removed. On adding a further quantity of alcohol to the hydroalcoholic layer, the gum ought to separate as a flocculent precipitate and can be tested as above described. Acacia gum contains an oxydase which causes the production of a blue color when an alcoholic solution of guaiacum is added to a solution of the gum. When a 5 per cent aqueous solution of the gum in cold water is treated with an equal volume of 1 per cent aqueous guaiacol and a drop of hydrogen peroxide added, a brown color develops. These tests may assist in the detection of acacia in the presence of other gums, but it is of no value in testing for it in pharmaceutical mixtures. The oxydase reaction was considered at one time to be limited to, and therefore char- acteristic of, gum arabic, but recent observations indicate that some of the cheaper grades of Smyrna tragacanths respond to the same tests. Jensen tested authentic specimens of the so-called Indian gums, from Sterculia urens and Cochlospermum gossypium, and obtained no reaction for oxidizing ferments. Acacia has a saponification value of about 10. Waters and Tuttle : have proposed the following method for the deter- mination of gum arabic : Fifty grams of copper acetate is dissolved in water, an excess of ammonia added, and the solution diluted to 1000 mils, using water and alcohol in such proportions that the final solution contains 50 per cent 1 Dept. of Commerce, Bu. of Standards, Technologic Paper No. 67, page 13. GUMS AND RESINS 465 of alcohol. For each determination a 50-mil portion of a gum arabic solu- tion, representing 0.25 gram of gum, is pipetted into a 250-mil beaker, an equal volume of alcohol added, and then 25 mils of the copper reagent, with constant stirring. The precipitate is allowed to settle, is filtered on a tared paper, washed with 50 per cent alcohol containing ammonia, then with 75 per cent, and finally with 95 per cent alcohol. It is dried to constant weight at 105°, ignited in a porcelain crucible, and the ash weighed. The amount of ash is deducted from the weight of the original precipitate and the difference called " net gum arabic." The amount of moisture in the gum originally taken for analysis must be allowed for. This is determined by drying in a current of Irydrogen at 105°. No allowance is made for the potassium and calcium, which forms an integral part of the gum. These may be to some extent retained in the precipi- tate and, therefore, be included in the ash. Any error that may be intro- duced by neglecting this is small and very much less than the error inherent in the method. This procedure can be applied to admixtures of gum arabic with tragacanth. The mixed gums should be digested with water, the solution made up to a definite volume, allowed to settle and an aliquot decanted for the determination. The application of this method to mixtures of acacia and Indian gum has not been determined. With dextrin it would apparently work successfully. If it is proposed to use this method for determining acacia in pharma- ceutical mixtures the gum should first be separated, as was recommended in making the qualitative tests. The gum of the mesquite tree of Texas occurs in tears and somewhat resembles acacia in its physical properties, but it does not yield the char- acteristic precipitates with lead subacetate and ferric chloride. Agar Agar Agar has recently come into prominence as a remedy for constipation. The commercial product consists of the stems of marine algae, of which the most important are Gelidium corneum, G. cartilagineum, Fucus amylaceus syn. Gracillaria confervoides, Euchema spinosum Ag, and cer- tain species of Tenax and Digartineae. Agar occurs in transparent strips of the thickness of straw, or in shorter and thicker yellowish-white pieces, odorless and tasteless. The aqueous solution gives no precipitate with tannic acid (absence of gelatin) and no blue color with iodine. A fragment of the material, however, under the microscope, stained with iodine, will show bluish black in places. Commercial agar usually contains diatoms, a characteristic form being Arachnoiliscus Ehrenbergii. To obtain the diatoms the organic matter may be oxidized with a mixture of nitric and sulphuric acid. These 466 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS diatoms are disk-shaped and from 0.1 to 0.2 mm. in diameter. Spiculae of sponges are often present. The characteristic swelling and jellifying properties of agar are due to d-galactan or gelose. C. R. Fellers 1 has recorded an interesting research on agar. The average proximate analysis of a number of samples gave moisture 16.57 per cent, protein 2.34 per cent, nitrogen-free extract 76.15 per cent, ether extract .30 per cent, crude fiber 0.80 per cent, ash 3.85 per cent, silica 0.68 per cent. The average analysis of agar showed : Per Cent Per Cent CaO 0.92 As 2 3 0.000 MgO 0.568 CI 0.22 NaaO 0.25 I Present K 2 0.067 Pentosans 3.12 FeaOs+AlaOs 0.55 Galactan 22.87 Si0 2 0.83 Solution in water, 20° 19.00 S0 2 2.645 Solution in water, 100° 96.20 P 2 5 . 052 Protein in alcohol precipitate .... 1.12 Mils excess N/1 HC1, per gram 0.029 The solubility in cold water was determined by placing 5 grams of the air-dried substance in a flask containing 200 mils of water and allow- ing it to stand for eighteen hours with occasional shaking. The acidity was determined by treating 5 grams with 250 mils of water, heating until solution had taken place and then titrating 100-mil portions using phenolphthalein. The relatively high content of sulphur is no doubt due to the practice of bleaching with sulphur dioxide. The ether extract is an aromatic-scented, fight, amber colored, fatty substance of about the consistency of stearin. A high ash or silica content is indicative of an inferior product. Agar solutions are partly precipitated or rendered " tacky " with alcohol. Lead subacetate produces a precipitate, but neither lead acetate nor borax causes precipitation. Irish Moss Irish moss consists of the fronds of Chondrus crispus and Gigartina rnamillosa (Gigartinacese), marine growths, which are collected in large quantities. When fresh the color is purplish, but on drying the color disappears in part and as usually found in commerce Irish moss occurs in matted, horny, translucent masses of a yellowish or yellowish-white color. 1 J. Ind. and Eng. Chem., 1916, 8, 1128. GUMS AND RESINS 467 The mucilage is an important emulsifying agent and is often employed in lotions and jellies. Its presence may be suspected in any product of the type which does not yield a gummy precipitate with alcohol. It is often present in applications for sunburn, chapped hands, chafing, and similar discomforts and in such, aids in distributing the beneficial action of Ham- amelis distilled extract, boric acid, and glycerin. Irish moss softens and becomes gelatinous in cold water and yields a gummy constituent to boiling water. The solution is viscous and jelli- fies on cooling. It gives no precipitate with gelatin, lead acetate, borax, or alcohol, and is not colored blue by iodin. It gives a precipitate with lead subacetate. Quince Seed Quince seed contains a gelatinous substance which is readily soluble in cold water, and mucilage thus produced is a valuable emulsifying agent. It is employed in the preparation of lotions and creams. The seed con- tains a cyanogenetic glucoside, and under ordinary conditions this passes into the emulsion, and will be apparent through the hydrolysis and liber- ation of the benzaldehyde and hydrocyanic acid. Quince-seed emulsion is not precipitated by alcohol or borax, but it gives precipitates with lead acetate and subacetate. Gum Tragasol Gum Tragasol is the name given to a product obtained as a result of steeping locust-bean kernels with water. Tragacanth Tragacanth gum is obtained from shrubs of the Astragalus genus growing principally in Persia and Asia Minor. It enters commerce, as a rule, through ports in Persia, and from there is shipped to Russia, Great Britain, Turkey, India, and the United States. Previous to 1915 large shipments were handled through Hamburg. The exudations from the gum-bearing species of Astragalus resemble one another closely in physical and chemical characteristics. The whole gum usually occurs in ribbon-like bands or long linear pieces, flattened and often spirally twisted, varying in color from white to light brown. It has a horny appearance and is translucent and opaque when the pieces are dark-colored and thick. The bands are usually marked with ridges. The composition of the gum is complex. The literature contains the reports of several researches, but it is difficult to coordinate the results. O'Sullivan has determined the presence of starch, cellulose, nitrogenous matter, bassorin, and soluble gum. The soluble gum is built up with complex acids which he terms polyarabinan-trigalactan-geddic acids and 468 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS which on hydrolysis yield arabinose. Bassorin, the insoluble portion, is of acid-like character and under the action of excess alkali yields two acids, alpha and beta-tragacanthan-xylan-bassoric acid, the former being readily soluble in water. 0' Sullivan found the formula of the alpha acid to be C24H34O20 • H2O, and on digestion with 5 per cent sulphuric acid at 98° for twenty minutes it was hydrolyzed to tragacanthose and xylan- bassoric acid; the latter subsequently being resolved into xylose and bassoric acid by 5 per cent sulphuric acid. Bassoric acid is almost insolu- ble in cold water. It forms a jelly with alcohol. Tragacanth in the whole condition is recognized without difficulty. The finer grades are white and in thin pieces, the cheaper grades being darker in color and less uniform in appearance, some grades being almost entirely without the ridged and banded structure. The powder is often adulterated. Pure tragacanth when made into mucilage with water yields an opaque mixture which is neutral in reaction, froths when shaken with 5 per cent potassium hydroxide, gives a blue color with iodin and pre- cipitates immediately with 2 volumes of alcohol. When the mucilage is mixed with an equal volume of 2 per cent borax solution no change in consistency is exhibited, and after standing for twenty-four hours it pours out as a homogeneous mixture without stringiness. When boiled with hydrochloric acid the mucilage develops a yellow to brownish tint with separation of a flocculent precipitate. High-grade tragacanth has a saponification value of 140-186. Its ash should not be over 3.5 per cent. It yields from 2-2.5 per cent acetic acid on hydrolysis with mineral acids. As a remedial agent tragacanth is valuable chiefly as an emollient. It is extensively employed as a mechanical agent in the preparation of emul- sions and pills. It is reported that certain lump tragacanths give reactions for oxidizing ferments which have been attributed to acacia alone. The procedure of the test has been detailed under the description of acacia. Fromme * recommends a method for determining the approximate percentages of acacia and tragacanth when mixed. Two grams of puri- fied sand is placed in a strong test-tube 16X150 mm., with 0.1 gram of the powder to be examined and the contents well mixed by shaking; 1 mil of alcohol is then added, followed by 5 mils of water, and, after shak- ing well, 20 mils of an ammoniacal solution of copper oxide (cuoxam). The tube is then vigorously shaken and set aside for several hours. A similar test is carried out simultaneously with powdered tragacanth of known purity. On comparing the two tubes the height of the deposit will give a fairly good indication of the percentage of real tragacanth in the sample. 1 Jahresbericht, Caesar and Lorenz, 1914, p. 28. GUMS AND RESINS 469 The reagent is prepared by shaking copper turnings or powder with 25 per cent ammonia until the solution becomes deep blue. Berlinia emini gum The gum from Berlinia emini, indigenous to German East Africa and identified by F. Mannich, resembles tragacanth. It occurs in horny brown opaque pieces with a slight peculiar odor and contains no starch. It yields an acid mucilage which is precipitated by lead acetate. Indian Gum There are several gums known as Indian gum, but none of these is obtained from any species of Astragalus. The name kuteera, katirah, and the same with many other spellings, has been applied to some of the Indian gums and to certain of the Astragalus products, the gums from A. hera- tensis and A. strobilifera, and it has no special significance and does not indicate the origin or proper classification of the gum. While it is possible that the Indian gum used so extensively in this country may vary as to its origin, the specimens examined in the whole condition correspond with samples of gum Sterculia urens submitted directly from India and from London. Furthermore, in a private report submitted from Bombay it is stated that S. urens is the source of this gum, and that it is used as a substitute for tragacanth in the government hospitals in Bombay. It occurs in striated hveguiar lumps, sometimes twisted, transparent or translucent and not in ribbony bands like tragacanth. As it reaches this country it often contains considerable bark which is bolted out before the powdered material is ready for the market. The powder is usually very white, rivaling in appearance that of the best grades of tragacanth. The bark contains characteristic stone cells winch pass into the powder, and serve as a means of identifying the source of the product. Tragacanth bark contains no substance of similar character. The powder of Indian gum forms a nearly transparent jelly with water, < swelling up to a considerable bulk and apparently dissolving, though, as a matter of fact, a small portion only is taken into solution. The aqueous solution is decidedly acid to litmus. It is unaffected by iodine solution and does not give a yellow color when warmed with alkali. When an aqueous mixture of this gum is boiled with dilute hydro- chloric acid, a clear solution with a marked pink color results. Indian gum reacts in a peculiar manner with borax; referred to at some length by Scoville, 1 which property is of value in detecting mix- tures. Tragacanth gives a smooth creamy mixture, Indian gum a thick 1 Druggists' Circular, 1909, 116. 470 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS slimy mass, often so gelatinous that it will not pour out of the container, this property being apparent even in presence of considerable amounts of tragacanth. The test is best performed by placing 2 grains of the powder in a 100-mil graduated cylinder, moistening with alcohol and adding about 50 mils water, shaking until a homogeneous mixture is obtained; 2 grams of borax are dissolved in 50 mils of water, added to the jelly, the whole well shaken and allowed to stand overnight. When pure traga- canth alone is under examination, the resulting mixture will pour out of the cylinder without stringing, while if Indian gum is present a stringy mixture results. Indian gum evolves a relatively large amount of acetic acid when boiled with sulphuric or phosphoric acids. This property furnishes another ready means of detecting, as well as approximately estimating the quantity of the gum present in admixtures with tragacanth. Emery 1 has determined that the average volatile acidity of the gum from S. urens is 15.79 per cent. His procedure for determining the volatile acidity is as follows: Treat 1 gram of the whole or powdered sample in a 700-mil round- bottomed flask, provided with a long neck, for several hours in the cold with 100 mils of distilled water and 5 mils of sirupy phosphoric acid until the gum is completely swollen. Boil gently two hours in connection with a reflux condenser, whereby a nearly clear, colorless solution is effected. A very small amount of cellulose substance will remain undissolved. Now subject the hydrolyzed product to slow distillation in a vigorous current of steam until the distillate amounts to 600 mils and the acid residue to about 20 mils. This should not be driven too far, however, otherwise there may be danger of scorching the nonvolatile, organic degradation products, with consequent possible contamination of the distillate. It has been found that a spray trap if used in connection with the flask containing the hydrolyzed gum, is effective in preventing traces of phosphoric acid being carried over into the distillate. Titrate with N/10 potassium hydroxide in connection with 10 drops of phenol- phthalein solution, finally boiling the liquid under examination until a faint pink color persists. Run a control on same amount of distillate obtained by a parallel operation, with omission of gum, but using like quantities of other ingredients and observing the same conditions as in the test. The published data on the Indian gums lack coordination. This may be due in part to the uncertainty of the botanical sources of the product. The information thus far obtained refers to two sources, Sterculia urens and Cochlospermum gossj^pium. The published data on both gums show that the two products are closely allied if not identical in composition. 1 U. S. Dept. Agri. Bu. Chem. Circ. 94. GUMS AND RESINS 471 Lemeland 1 and later Robinson 2 have conducted researches on a gum which they attribute to C. gossypium, but which is apparently the same as or closely allied to the gum from S. urens. The gum was obtained from a small deciduous tree of Northwestern Himalaya and central India. An examination of the gum furnished the following results: Moisture, 22.72 per cent; ash, 4.64 per cent; the ash contains iron, calcium, and potassium as oxide and carbonate. 2.04 per cent of the gum is soluble in water, the solution possessing a rotatory power of +77.15°. Determi- nation of the galactans by Tollen's method gave 34.99 per cent (expressed as galactose). No arabinose or sugar other than ^-galactose could be isolated from the products; 22.59 per cent of pentosans, equivalent to 25.64 per cent of pentoses, was found. The total quantity of sugar could not be determined, owing to the difficulty experienced in hydrolysing the gum, the highest result obtained being less than the sum of the pen- tose and galactose. On oxidation with nitric acid, 71.8 per cent of mucic acid (on the weight of gum used) was obtained. The gum examined by Robinson contained 15.5 per cent of water (loss at 100° C.) and 5.2 per cent of ash. It was investigated according to the method proposed by O'Sullivan. It probably consists of the tetra- acetyl derivative of a gummy acid to which the name a-cochlosperminic acid was given. This acid, probably C34H54O30, was isolated by treating 100 grams of the gum with 2 liters of 5 per cent sodium hydroxide solution, and after standing for a long time, nearly neutralizing the mucilage with dilute hydrochloric acid, again allowing to stand for a few days, and then adding excess of strong hydrochloric acid solution. The solution was purified by dialysis, and the free gum-acid precipitated by alcohol and a small quantity of hydrochloric acid, washed with alcohol, and dried. It is a white granular substance, having a rotatory power (a) D = +57°; It gelatinized with water, but does not dissolve. On hydrolysis with dilute sulphuric acid, the gum yields 14.4 per cent of acetic acid, a gum- acid (gondic acid), and two sugars — xylose and hexose, possibly galactose. Gondic acid, C23H36O21, is soluble in water and is precipitated from solu- tion by alcohol as a white amorphous substance. It is an anhydride, and has the rotatory power (a) D = +97.7. RESINS The main constituents of resins may be divided into the following classes : 1. Resin esters (resins) or their products. 2. Resin acids (resinolic acids). 1 J. Pharm. Chim., 1904, 20, 253. 2 Chem. Soc. Trans., 1906, 89, 1496. 472 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS 3. Resenes, indifferent bodies of unknown classification. The aroma of resins is due in part to ethereal oils and liquid esters, among which cinnamic acid esters are important. 1. Resin Esters The resin esters and resins are composed of aromatic acids of the ben- zoic and cinnamic series and resin alcohols (resinols and resinotannols) . Succinic acid, an aliphatic acid, occurs in amber. a. Benzoic acid, CeHsCOOH, (Peru and Tolu balsams, Siam benzoin, dragon's blood) Benzoylacetic acid, CH 2 (C 6 H5CO)COOH ; (Dragon's blood) .OH Salicylic acid, QqQa<^ (Ammoniacum) x COOH b. Cinnamic acid, C6H5CH==CHCOOH (Peru and Tolu balsams, Storax, Sumatra benzoin) /OH P-cumaric acid, CeH4\ (Aloes) \CH=CHCOOH /OH (1) Ferulaic acid, C6H3OCH3 , (2) (Asafetida) \CH-=CHC00H (4) /OH (1) Umbellic acid, C6H3OH , (3) with its anhydride \CH=CHC00H (4) Umbelliferone (Asafetida. Galbanum) Resin Alcohols. Resinols do not give a tannin reaction. Resinotan- nols are colored by iron salts. Resinols. Succinoresinol, C12H20O (Amber) Storesinol, (Storax) Benzoresinol, CioH 2 5(OH)0 (Benzoin) Chironol, C28H47OH (Opopanax) Resinotannols. Siaresinotannol, Ci 2 Hi 3 2 (OH) (Siam benzoin) Sumaresinotannol, Ci 8 Hi 9 3 (OH) (Sumatra benzoin) Peruresinotannol, C] 8 Hi 9 4 (OH) (Peru balsam) Toluresinotannol, Ci 7 Hi 7 4 (OH) (Tolu balsam) Galbaresinotannol, Ci 8 H290 2 (OH) (Galbanum) Ammoresinotannol, Ci 8 H 2 90 2 (OH) (Ammoniacum) Sagaresinotannol, C 2 4H 27 4 (OH) (Sagapenum) Dracoresinotannol, C 8 H y O(OH) (Palm dragon's blood) GUMS AND RESINS 473 Panaxresinotannol, C34H49O7 (OH) Xanthoresinotannol, C43H46O10 Erythroresinotannol, C40H40O10 Aloeresinotannol, C22H 2 505(OH) Asaresinotannol, C24H3s04(OH) Oporesinotannol, Ci2Hi302(OH) Some of the resinotannols yield picric acid when treated with nitric acid; ammoresinotannol and sagaresinotannol yield trinitroresorcin; gal- baresinotannol yields camphoric acid and camphoronic acid. When fused with potash, aliphatic acids are liberated and in some cases protocatechuic acid and resorcin. (Opopanax) (Yellow acaroid) (Red acaroid) (Aloes) (Asafetida) (Umb. opopanax) 2. Resin Acids These acids all contain hydroxyl. Abietic acid, C20H40O2 (Colophony) Pimaric acid, C20H30O2 (Pine resin) Succinoabietic acid, C80H120O5 (Amber) Sandaracolic acid, C45H66O7 (Sandarach) /OCH3 C4 3 H 6 i0 3 ^OH \COOH Callitrolic acid, C65H84O8 (Sandarach) X)H C64Hg205\ XJOOH Trachylohc acid, CseHssOg (Copal) Isotrachylolic acid, CseHgsOg (Copal) Dammarolic acid, CseHsoOs (Dammar) Guaiacic acid, C20H26O4 (Guaiacum) Guaiaconic acid, C19H20O5 (Guaiacum) Copaibic acid, C20H30O2 (Copaiba) Elemic acid, C35H46O4 (Elemi) Masticinic acid, C20H32O2 (Mastic) Acid, Ci 3 Hi 6 8 1 Acid, C26H32O9 J (Myrrh) Acid, (C 9 H 13 02)„ (Bisabol myrrh) Boswellic acid, C32H52O4 (Olibanum) 3. Resenes The classification of these substances is uncertain. They are indif- ferent to the usual class reagents and are insoluble in potash. a-Panaxresene, C32H54O4 (Opopanax) /3-Panaxresene, C32H52O5 (Opopanax) a-Dammarresene, C33H52O3 (Dammar) j8-Dammarresene, C31H52O (Dammar) 474 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Fluavil, C40H64O4 (Gutta percha) Alban, C40H64O3 (Gutta percha) a-Copal resene, C25H38O4 (Copal) Dracoalban, C20H40O4 (Palm dragon's blood) Dracoresene, C26H44O2 (Palm dragon's blood) Masticin, C20H32O (Mastic) Resene, C26H34O5 (Myrrh) Resene, (C29H470e)n (Bisabol myrrh) .Alibanoresene, (C^H^O)*, (Olibanum) METHODS FOR ANALYZING AND DETERMINING THE CONSTANTS OF RESINS When working with resins of known identity the analyst can proceed to determine the constants by the methods described below which have been found most applicable. When the resin is of uncertain identity, or in case it is a new and hitherto unreported body, its general character- istics must be ascertained before proceeding with the estimation of its constants. In order to arrive at a basis for future work the proximate analysis of the resin can best be obtained by following the procedure recommended by Tschirch. The sample is dissolved in a suitable solvent, such as ether or chloro- form, and shaken out successively with a 1 per cent solution of ammonium carbonate; a 1 per cent solution of sodium carbonate; a 0.1 per cent solution of potassium hydroxide; and a 1 per cent solution of potassium hydroxide. These reagents dissolve out the free resin acids, which can be recovered by acidulating with hydrochloric acid and shaking out with the proper solvent. The material remaining in the volatile solvent and which was inert to the alkaline solutions is distilled with steam, which removes any volatile substances and the solvent. The residue will con- sist of resin-esters and resenes. On saponification with alcoholic potash the acids liberated will go into the alkali, and on shaking up with ether the resin-alcohols and resenes are separated. The resin-alcohols are then separated from the resenes by acetylization or benzoyation. The identi- fication of the acids may be accomplished by resorting to the regular scheme of qualitative organic analysis and with these data in hand and an approxi- mate idea of the relative proportion of the resinous constituents, the proper methods of analysis can be selected. Resin-esters predominate in benzoin, Peru and Tolu balsams, storax, acaroid resins, aloes resins and dragon's blood (all so-called benzo-resins) and in the umbelliferous gum resins, ammoniacum, galbanum, sagapenum, asafetida, and umbelliferous opopanax. GUMS AND RESINS 475 The resin acids predominate in the terpeno-resins from coniferous trees, colophony, copaiba, and Zanzibar copal. The resenes predominate in the burseraceous oleoresins, myrrh, oli- banum, bdellium, burseraceous opopanax, elemi, mastic, and the diptero- carpus products, Doona resin, dammar, and Manila copal. When working with natural drugs an average sample may be prepared by grinding at least 100 grams of the dry drug as finely as possible. Bal- sams should be well shaken and resins containing water should be freed from moisture and stirred up well together. Gum resins which are soft and difficult to pulverize should be cooled by immersion of the mortar in a good refrigerant. When the parcel is large the samples should be drawn from various parts of the bulk. A resin analysis may include the determination of the following data: Acid Value. The number of milligrams of KOH combined by the free acid in 1 gram of resin during direct or back titration. The acid value of the volatile portion is the number of milligrams of KOH combined by 500 mils of distillate obtained from 0.5 gram of gum resin by distillation with steam. Ester Value. The difference between the saponification value and the acid value. Saponification Value. (Hot — Cold). The number of milligrams of KOH combined by 1 gram of resin in hot or cold saponification. The total saponification value (fractional sapon.) equals the number of milligrams of KOH combined by 1 gram of cer- tain resins and gum resins on cold fractional saponification with alcoholic and aqueous alkali in succession. Moisture. Ash. Amount Soluble in Alcohol. Amount Insoluble in Alcohol. Amount Soluble in Other Solvents. Specific Gravity. Resin Value. The number of milligrams of KOH combined by 1 gram of certain resins and gum resins on cold saponification with alcoholic alkali by itself. Gum Value. The difference between the saponification value and the resin value. Acetyl Value. The difference between the acetyl saponification value and the acetyl acid value. Acetyl Acid Value. Acetyl Saponification Value. Acetyl Ester Value. 476 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Carbonyl Value. The percentage of carbonyl oxygen in the substance taken. Methoxyl Value. The amount of methoxyl furnished by 1 gram of resin. Special determinations, such as cinnamein and resin esters in Peru balsam. In the case of soft resins and balsams the weighing should be con- ducted on a watch-glass or a closed weighing bottle, removing the desired quantity by means of a glass rod, and inserting the rod and adhering material into the receptacle for conducting the assay. In comminuting and reducing to a powder samples that are sticky, the end in view may be attained by storing the products in a cold place, which will usually render them hard and easily comminuted. Warming or heating in a drying oven should be avoided. All results should be cal- culated to the natural crude drug and not to goods dried at 100°. (The methods herein offered have been correlated and tested out by Karl Dieterich, to whom full acknowledgment is accorded.) Acid Value 1. Direct titration. (a) When the sample is soluble in alcohol, chloroform and suitable neutral organic solvent. One gram is dissolved in a suitable solvent or mixture and titrated with N/2 or N/10 alcoholic potash using phenol- phthalein as indicator. (6) After the preparation of an alcoholic extract in the case of imperfectly soluble resins, the extract being used for titration. Applicable to gum resins, benzoin, storax. Same as above. The results may be calculated to 1 gram of the extract instead of the crude product. (c) Of the solution obtained by extracting a partially soluble resin with water and alcohol. Applicable to myrrh, bdellium, opopanax, and sagapenum. One gram of the finely ground resin is extracted by boning with 30 mils of water under a reflux for fifteen minutes, followed by the addition of 50 mils of alcohol 96 per cent, and reboiling for an equal period. After cooling the extract is titrated with- out filtration with N/2 alcoholic potash. 2. Back titration. (a) In the case of completely (or nearly) soluble resins, free from esters, where the alkali combines with the acid and at the same time dissolves the resin. Applicable to dammar, sandarach, mastic, guaiacum, copal, etc. One gram of the finely divided (ester free) resin is left in con- GUMS AND RESINS 477 tact with 25 mils of N/2 alcoholic potash and 50 mils of petro- leum ether in a stoppered flask for twenty-four hours or until solution has been carried as far as possible, and is then titrated back with N/2 sulphuric acid and phenolphthalein. (6) In the case of partially soluble — esteriferous but sparingly saponifiable — resins, where the alkali fixes the acid and at the same time dissolves the resin. Applicable to asafetida and olibanum. One gram of the finely powdered substance is left for twenty- four hours in contact with 10 mils of N/2 alcoholic potash and 10 mils of N/2 aqueous potash in a stoppered flask. It is then mixed with 500 c.c. of water and titrated back. (c) In the case of resins that are only partially soluble and contain esters, an aqueous alcoholic extract being employed. Applicable to ammoniacum, galbanum, gamboge. One gram of the finely divided resin is boiled for fifteen minutes • under a reflux with 50 mils of water, after which 100 mils of strong alcohol are added and the whole boiled again for fifteen minutes. After cooling the whole is made up to 150 mils and filtered, 75 mils of the filtrate (equivalent to 0.5 of the sample) being treated for five minutes with 100 mils of N/2 alcoholic potash and then titrated back. (d) In the case of soluble resins which contain esters and are easily saponified. The natural drugs are used. Applicable to ben- zoin. Ten mils of N/2 alcoholic potash are allowed to act for five minutes on 1 gram of the drug, and then titrated back. 3. By estimating the volatile acids. In the case of gum resins rich in ethereal oils. Applicable to ammoniacum, galbanum. 0.5 gram of the sample is treated with a little water in a flask, and a current of steam is passed through, the flask being heated. The receiver contains 40 mils of N/2 aqueous potash, into which dips a tube from the condenser. Exactly 500 mils of distillate are collected, the condenser tube is washed out with distilled water and the whole titrated back. In this case the acid value gives the number of milligrams of KOH neutralized by 0.5 gram resin. Ester Value This is calculated by subtracting the acid value from the saponification value except in cases where the acid value has been determined as under 3, 478 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS and where a resin value and total saponification value are present. In such event the ester value cannot be calculated. Saponification Value 1. By the hot method. (a) In the solutions of completely soluble resins. Applicable to nearly all balsams and resins for which no special methods have been devised. On3 gram of the resin is dissolved in 25 mils of N/2 alcoholic potash, boiled at temperature of steam-bath for one-half hour under a reflux, diluted with alcohol and titrated back. (6) In the case of previously prepared alcoholic extract of a parti- ally or sparingly soluble resin. Applicable to gum resins, benzoin, storax. The same procedure as under a, except that an alcoholic solu- tion of the extract is taken, the results being calculated to 1 gram of the crude drug and not of the extract. (c) In the case of gum resins partly soluble in water. Applicable to myrrh. The same procedure as under a except that the crude drug is taken after the addition of water to dissolve out the gum. 2. By the cold method. (a) In the case of perfectly soluble resins with cold alcoholic potash and petroleum ether only. Applicable to Peru balsam, copaiba, benzoin, storax. One gram of the substance is treated in a stoppered 500-mil flask with 50 mils petroleum ether (sp. gr. .700 at 15° C.) and 50 mils N/2 alcoholic potash. After standing twenty-four hours at room temperature, it is titrated back with N/2 sul- phuric acid. In some cases (Peru balsam) it is necessary to add 300 mils of water to dissolve precipitated salts. (b) In the case of imperfectly soluble resins. This procedure is a fractional saponification, including " resin value " and " gum value," alcoholic and aqueous alkali, with an addition of petroleum ether, being used in succession. Applicable to ammoniacum, galbanum, gamboge, dragons blood, lactucarium. Two samples, each of 1 gram, of the resin are powdered and suffused in separate 1-liter stopper flasks with 50 mils of petro- leum ether (sp. gr. 0.700 at 15° C.) followed by 25 mils of N/2 alcoholic potash. After standing closed for twenty-four hours at room temperature, with frequent shaking, the one sample is shaken up with 500 mils of water and titrated back with N/2 GUMS AND RESINS 479 sulphuric acid; this gives the " resin value." The second sample is then further treated with 25 mils of N/2 aqueous pot- ash and 75 mils of water and left for another twenty-four hours with frequent shaking, being finally diluted with 500 mils of v/ater and titrated back. This gives the " total saponification value " the difference between this and the resin value being the " gum value." Acetyl Value In the method proposed by K. Dieterich for determining the acetjl value of resins, the substance is boiled under a reflux condenser, with an excess of acetic anhydride and a little anhydrous sodium acetate, until completely dissolved, or until it is evident that no further portion will pass into solution. The solution is poured into water, and the precipitate then ensuing is collected and extracted with boiling water until perfectly free from all traces of uncombined acetic acid. The insoluble residues left by copal and dammar are also treated in the same manner. The dried acetylized products are then tested for the acetyl, acid, ester, and saponi- fication values by dissolving 1 gram in cold alcohol and titrating with N/2 caustic potash. The saponification is also effected with N/2 alkali for half an hour under a reflux condenser, and the product titrated back after cooling down and dilution with alcohol (not water). As in the case of fats, the difference between the acetyl-saponification value and the acetyl-acid value gives the true " acetyl value." Carbonyl Value The substance under examination is warmed with sodium acetate and an accurately measured quantity of phenylhydrazine chloride in dilute alcoholic solution. The excess of hydrazine salt not sharing in the reaction is then ascertained by eliminating the nitrogen by oxidation with Fehling's solution and collecting the gas in a measuring tube. The carbonyl value, i. e., the percentage of carbonyl oxygen in the substance taken, is ascer- tained by the formula 0=V—Vo , wherein V—Vo indicates the difference in the volume of nitrogen reduced to or 760 mm., and S refers to the weight of the substance in grams. Methoxyl value {Zeisel) As this method entails the use of apparatus and special precautions, it is considered preferable to repeat the author's own description in full. The Zeisel apparatus is made up as follows: A reflux condenser, fed 480 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS with water at 40-50° C, is fitted with a small flask, the neck of which is provided with a lateral tube for the introduction of carbon dioxide. The upper end of the condenser tube is connected with a Geissler potash appa- ratus which is charged with amorphous phosphorus suspended in water, and is placed in a water-bath kept at about 50-60° C, its purpose being to free the current of alkyl-iodide vapor passing through from hydriodic acid and iodine vapor. The alkyl iodide is led into a 4 per cent solution of silver nitrate in two successive flasks, the whole being generally retained and converted into silver iodide in the first one. In performing the experi- ment, the substance to be examined for methoxyl is heated along with 10 c.c. of hydriodic acid of sp.gr. 1.68, CO2 being passed through the appa- ratus. The experiment is complete when the liquid in the first flask has become clear above the deposit of silver iodide, and the silver iodide is then determined by gravimetric means. For ordinary analyses it is sufficient to use 50 mils of the silver nitrate solution in the first flask, and 25 mils in the second, after acidification with a few drops of nitric acid free from nitrous acid. After the reaction is terminated — ZeisePs conditions being otherwise maintained through- out — the clear liquid above the silver iodide is poured off into a 250-mil measuring flask. The silver nitrate solution in the second flask is diluted with water and poured into the same measuring flask, the contents of which are thereupon made up to the mark with water, agitated well, and passed through a folded filter into a dry vessel. For the titration, 50 or 100 mils of the filtrate are used, after suitable acidification with nitric acid (free from nitrous acid) and an addition of ferric sulphate solution. SEPARATION OF RESIN ACIDS AND FATTY ACIDS In the case of a fatty acid adulterated with resin, about 0.6 gram of the substance is dissolved in 20 mils of 95 per cent alcohol. To this solution is added a trace of phenolphthalein, and a solution of alcoholic potash is run in, drop by drop, from a burette, with continued stirring, until the indicator has assumed a dark red color, characteristic of alkalinity. After adding one or two drops of the potash solution in excess, the flask containing the liquid is placed on the water-bath and the contents boiled for ten minutes. When cold, the whole is poured into a 100-mil test-tube, the flask washed with ether, and — the whole being made up to 100 mils with this solvent — the tube is corked and shaken up thoroughly. Next, 1 gram of finely divided silver nitrate is introduced and shaken up well for ten to fifteen minutes, until the flocculent deposit of silver st ear ate or oleate has collected together at the bottom of the tube. Then 50-70 mils of the clear liquid are removed by means of a pipette, and GUMS AND RESINS 481 transferred to another 100-mil test-tube, where a further small quantity of silver nitrate is added to remove the fatty acid still in solution. The clear liquid is then mixed with 20 mils of dilute hydrochloric acid (one-third 21 per cent HC1 and two-thirds water) ; an aliquot part of the supernatant ethereal solution is evaporated in a platinum basin, the residue — dried in the steamer — being resin, accompanied by a little oleic acid. Direct experiment has shown that, under these conditions, 10 mils of ether retain on an average 0.00235 gram of oleic acid, so that the result of the analysis may be corrected by means of this coefficient. The method is applicable to the determination of resin in linseed oil, soap, etc. CLASSIFICATION OF INDIVIDUAL RESINOUS SUBSTANCES Resins Oleo Resins Balsams Gum Resins Aloes Canada Balsam Peru Ammoniacum Anime Copaiba Tolu Bdellium Amber Cubeb Euphorbium Benzoin Gurjun Balsam Galbanum Colophony Gamboge Dragon's Blood Lactucarium Elemi Myrrh Guaiacum Sagapenum Jalap Asafetida Kino. Red Gum Olibanum Labdanum Opopanax Mastic Sandarach Scammony Chicle Shellac Gutta Percha Storax Caoutchouc Tacamahac Thapsia Turpentine Turpethura Podophyllum Of these Benzoin, Storax, Peru, and Tolu Balsams are treated more conveniently in the discussion of aromatic acids. Jalap and Scammony have been treated, and Podophyllum and Cubeb have also been described. Of the remainder the most important from the point of view of medical usage are Guaiacum, Kino, Turpentine, Copaiba, Ammoniacum, Gam- boge, Lactucarium, Myrrh, and Asafetida. The others have but a limited use as therapeutic agents or are employed only for their mechanical effect in the preparation of plasters, varnishes, and coverings for wounds and abraded surfaces and for coloring mouth washes. 482 GLUCOSIDES, GLUGOSIDAL DRUGS AND NATURAL DRUGS GUAIACUM RESIN Guaiacum resin is obtained from the wood of Guaiacum officinale and G. sanctum (Zygophyllacea?) . These trees grow in Cuba and some of the other West India Islands, the Bahamas, Hayti, and Jamaica. The wood is used medicinally for the same purposes as the resin. It is a hard, heavy wood, and known commercially as lignum vilce. The resin occurs in irregular or somewhat globular masses of a glassy luster and resinous fracture. The color is deep greenish brown or dark olive on the outer surface; the internal color which has not been exposed to the air is reddish brown or hyacinth, diversified with shades of various colors. It is brittle and presents a shining, glassy surface when broken. The taste is not perceptible at once, but soon becomes acrid and leaves a permanent sensation of heat and pungency. Guaiacum is employed as an alterative, stimulant, diaphoretic, and anti-rheumatic. It is dispensed in the form of a plain tincture and with aromatic spirit of ammonia. Liquid sarsaparilla compound contains guai- acum with sarsaparilla, sassafras, licorice, and mezereon bark. Compound tincture of guaiac or Dewer's tincture contains guaiac, potassium car- bonate, and pimento, and is a remedy for suppressed menstruation. Some of the pill and tablet formulas which may be mentioned include the N. F. Antimony Comp. (Plummer pills) which contains guaiac, calomel, sulphurated antimony, and castor oil, it will also be found combined with copaiba, cubeb, and ferric citrate; with calomel and opium; with aloes, sulphur, Podophyllum, and frangula; with potassium iodide, Phytolacca, colchicin, and digitalin (anti-rheumatic); with salicylic acid, sodium bicarbonate, and Colchicum ; with cantharides, aloes, and ferrous sulphate (emmenagogue) ; with ammonium chloride, licorice, and Hydrastis (throat); with senega, squill, aconite, Grindelia, ammonium carbonate, and ammonium bromide; with terpin hydrate, opium, wild cherry, and belladonna. It is dispensed alone in lozenges and may be found com- bined with Sanguinaria. Guaiacum mixture is an emulsion of guaiac with tragacanth, sugar, and cinnamon water. Guaiac occurs as the crude resin in which condition it is mixed with fragments of wood and bark and dirt; as the purified resin and in the form of tears. The pure resin consists of guaiacum resin (C20H23O3OH) ; guaiaconic acid (C2oH 2 20 3 (OH) 2 ); guaiacic acid (C 2 iHi 9 04(OH) 3 ); guai- acol and guaiacum yellow (C20H20O7). It often contains up to 9 per cent of gum. Pure resin is almost completely soluble in alcohol, chloroform, and acetic ether, and all but about 10 per cent is soluble in ether and benzol, though Evans reports commercial samples running as high as 11.7 per cent. GUMS AND RESINS 483 Pure resin has only a slight amount of ash. The acid value may run from 89-98, but Dieterich records the tears as running from 72-76, and Evans finds 45-56. The methoxyl values have been reported from 73.8-84. ' Dieterich has determined the acetyl values and found Acetyl Acid Value Ester Value Sapon. Value Purified 13.57-14.89 149.33-149.75 163.22-164.22 Commercial Crude .... 45 . 84-53 .15 121 . 75-129 . 16 167 . 59-192 . 44 Dieterich recommends the following procedure for determining the acid value. One gram of the resin is suffused with 10 mils N/2 alcoholic potash and 10 mils N/2 aqueous potassium hydroxide, and left for twenty- four hours in a glass-stoppered flask. After adding 500 mils of water the liquid is titrated back with N/2 sulphuric acid and phenolphthalein. Adulteration with colophony is indicated by a high acid value and the adulterant can be identified by the Storch-Morawski test applied to the abietic acid, which is first separated by treating an alcoholic solution with an excess of potassium hydroxide. Guaiac is adulterated with a similar product of yellowish-brown color known as Peruvian guaiacum (Guaiacum peruvianum odoriferum). Admixture with this resin may be detected, according to Hirschsohn, by treating a chloroformic solution with bromin fumes, which produce a red color, whereas pure guaiac solutions turn blue. An alcoholic solution of guaiac gives a blue color with tincture of ferric chloride, manganic and silver salts, nitric acid, chlorin, gluten, mucilage of acacia, milk, and with hydrocyanic acid, followed by copper sulphate. Citric acid prevents the production of the color with ferric salts, and egg albumen reduces the sensitiveness. It dissolves in cold concentrated sulphuric acid to a rich claret-colored solution which on dilution deposits a lilac-colored precipitate. Mammalian blood-stains, moistened with the tincture and followed by a few drops of dilute irydrogen peroxide, become blue in color. When analyzing a medicine guaiac will remain undissolved when an evaporated alcoholic extract of the product is treated with water. On treating the residue with chloroform, the guaiac will dissolve and the solu- tion may be filtered from any insoluble material, evaporated, and the residue dissolved in alcohol. Strips of clean white filter paper should be moistened with this tincture and when nearly dry exposed individually to the fumes of nitric acid and chlorin, which should produce blue colors in the presence of guaiac. Other strips should be moistened with tincture of ferric chloride and with hydrocyanic acid and copper sulphate. Drops of the tincture should be added to gluten, mucilage of acacia, and milk, 484 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS all of which should give positive reactions. A test should be obtained with blood-stains using the tincture followed by hydrogen peroxide. In the absence of other resinous drugs the proportion of guaiac in a medicine can be determined by extracting the powdered substance with alcohol, or treating an evaporated liquid mixture with alcohol. In either case the alcoholic extract thus obtained should be concentrated and poured into an excess of water, which will precipitate the resin. The liquid is decanted through a filter and after washing with water the resin is dis- solved in chloroform and the chloroformic liquid shaken with dilute sul- phuric acid. If the acid removes any basic substances the shaking is continued with successive portions of acid until a test with Mayer's reagent produces no precipitate. The chloroform is then washed with water, filtered into a tared dish, evaporated and the residue weighed, KINO The resins and gum-resins known as " Kinos " are obtained from a number of different sources. The resin which is known to the pharmacist as kino is obtained from Pterocarpus marsupium (Papilionacese) . Kinos from Eucalyptus rostrata and other species of Eucalyptus are known as " red gum." Kino is employed as an astringent. It is dispensed as a tincture and in pills and tablets, combined with camphor, opium, and Capsicum; diarrhea tablets contain kino, opium, camphor, bismuth subnitrate, sodium bicarbonate, and mercury with chalk. Red gum is a component of astringent lozenges and mouth washes, and is also used in seasickness. Kinos consist of dark-red or reddish-black resinous appearing brittle masses or granules, having an astringent taste and imparting a red color to the saliva. They dissolve in part or swell up in the presence of water, and the Pterocarpus kino is soluble in alcohol. They also dissolve in alkalies, but are nearly insoluble in ether. The resin of Pterocarpus marsupium contains a large porportion of a tannin known as kino-tannic acid, ash, kino-red, pyrocatechuic acid, and woody trash. The alcoholic solution tends to gelatinize. Aqueous solu- tions give a green color with ferric sulphate, changing to violet on the addition of alkali carbonates or acetates. Ferric chloride produces a green precipitate which turns purplish red in the presence of alkalies. Dilute mineral acids throw out a flocculent precipitate. The aqueous solution is precipitated by gelatin, and the soluble salts of silver, lead, mercury, and antimony. Commercial kinos differ in their properties. Good kino should show from 90-98 per cent soluble in 90 per cent alcohol, 85-95 per cent soluble GUMS AND RESINS 485 in water, 50-60 per cent tannin, not over 3 per cent ash and from 8-18 per cent moisture. The U. S. P. is considerably less rigid in its solubility requirements and provides for a product which should yield not less than 45 per cent to alcohol and not less than 40 per cent to boiling water. Eucalyptus kino is claimed to contain gallic acid and catechin in addi- tion to the other constituents reported in Pterocarpus. Thum found that less than 20 per cent was soluble in boiling water and that a solution of any strength would gelatinize unless glycerin was present THAPSIA RESIN Thapsia resin is obtained from Thapsia garganica (Umbellif era?) . It is a strong counter irritant and is sometimes used in plasters. The resin and the root of the plant when handled cause intense itching of the hands and exposed membranes. The blistering substance crystallizes and is reported to have a melting- point of 87° C. By successive extraction with alcohol and ether two resins have been separated, the former giving a scarlet color with sulphuric acid and the latter a blue color. Dieterich has developed a procedure for examining thapsia resin which avoids the dangerous consequences which would result by operating under ordinary conditions. About 1 gram of Thapsia resin is mixed with a sufficient amount of pure sand, and the crumbled mass placed in a Schleicher & Schull cartridge, the weight of cartridge + sand + resin being noted, as well as that of the cartridge + sand, and of the resin by itself. The whole is then treated, in a Soxhlet extractor, with petroleum ether for three hours, and, after cooling down, the cartridge is dried in the oven at 80° C. until no further odor of petroleum ether is discernible; longer drying must be avoided in view of the moisture-content of the resin. The cold petroleum ether extract is next treated with 20 mils of alcoholic N/2 caustic potash and boiled for half an hour under a reflux condenser, the apparatus being tightly stoppered. After cooling, the saponification value of the portion soluble in petroleum ether is determined by the usual method and the results are referred to 1 gram. The percentage soluble in petroleum ether is found, indirectly, by calculation, from the loss in weight of the aforesaid cartridge, and expressed as a percentage. The cartridge is then replaced in the extractor, and, after charging the bottom flask with 20 mils of alcoholic N/2 caustic potash and 50 mils of alcohol, is extracted for two hours longer. The alcohol serves as the extracting reagent, while the underlying alkali immediately saponifies the dissolved substances. After two hours the whole apparatus is cooled, and the cartridge is then dried at 100° C. until constant. 486 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The extra loss in weight, calculated m percentages, gives the value of the portion soluble in alcohol; the residue, which is easily calculated by deducting the weight of cartridge + sand from the total weight of cart- ridge + sand + resin, expresses the value, insoluble residue. The saponification liquid in the flask is titrated and — calculated to 1 gram — gives the saponification value (hot) of the portion soluble in alcohol. The total saponification value (hot) of the original resin is found by saponifying 1 gram of the resin with 25 mils of alcoholic N/2 potash, under a reflux condenser, and titrating back when cold. The following data were obtained on authentic thapsia: Per Cent Moisture 7.43- 10.33 Ash 0.16- 0.415 Soluble in petroleum ether 19 . 28- 25 . 67 Soluble in alcohol 83 .46- 89.32 Total Saponification value 336 . 33-384 . 47 Thapsia is adulterated with euphorbium and the resins of Thapsia villosa, which contains acrid substances but is milder in its action. TURPENTINE The various species of Pinus (the pines), Picea (the spruces), Abies (the firs), Tsuga (the hemlocks), and Larix (the larches), of the Pinacese yield oleoresinous exudations to which the name turpentine is gh r en. The pines which furnish the greater part of the turpentine gathered in the United States are P. palustris, the long-leaved or Georgia pine; P. taeda, the loblolly or old field pine; P. echinata, the yellow or spruce pine, and P. heterophylla, the Cuban or swamp pine. The exudation from Abies balsamea, the balsam fir, is known as Canada balsam, but the balsams from A. fraseri and Tsuga canadensis, the hem- lock, are collected for this product. A. excelsa yields Burgundy pitch. Venice turpentine is an exudation from the European Larix decidua. Russian turpentine is obtained from Pinus sylvestris, the type species of the Pinus, and which is regarded by some authors as belonging to a distinct genus from the several species of Pinus indigenous to the United States. Chian turpentine is obtained from Pistacia terebinthus and Strasburg turpentine from Abies picea. Turpentine consists of a complex mixture of turpentine oil, resin acids, colophony, and other substances. Turpentine oil, the limpid volatile fraction of the oleoresin, consists largely of d-pinene. Exception to this general statement occurs in the case of the French oil from P. pinaster (P. maritima). Camphene also occurs in turpentine oil. GUMS AND RESINS 487 Turpentine or more often the oil of turpentine is used externally as a rubefacient and counter-irritant and will be found with various other substances in liniments and embrocations. Internally it is employed as an anthelmintic, stimulant, hemostatic, emmenagogue, and antiseptic. It will be found in emmenagogue pills, in gonorrhea mixtures, cough tablets and elixirs and combined with copaiba and oil of cubeb in gelatin capsules. It is employed in remedies for dropsy as a diuretic, for tape worm, for rheumatism, and as an antidote for phosphorus poisoning. In many cases Venice turpentine will be found functionating in place of the Pinus turpentine Chian turpentine has been employed in the treatment of cancer. The turpentines are liquid when freshly gathered, but soon become thick on exposure, due to loss of volatile oil and oxidation. They soften on heating and burn with a smoky flame. They dissolve in the ordinary volatile solvents and in the fixed and volatile oils. When taken internally or applied to the skin they impart a violet odor to the urine. The acid value of turpentine ranges from 100-145. The ester value is reported from 2-60, the saponification value 108-180. Venice turpen- tine has a lower acid value, 60-80, and saponification values as low as 81 are reported, refractive index 1.518-1.521. Kremers reports the follow- ing rotation figures: (a) D oleoresin P. palustris — 13.665° (a) D oil P. palustris +23.93° (a) D oleoresin P. cubensis —32.428° (a) D oil P. cubensis + 9.6° Dieterich reports the following acetyl value for ordinary turpentine: Acetyl: Acid value 123.75-125.55 Ester value 62.32-93.79 Saponification value 187-87-217.04 For Venice turpentine: Acetyl: Acid value 69.87-72.19 Ester value 109.08-118.67 Saponification value 178.95-190.86 The admixtures of ordinary turpentine with Venice turpentine may be recognized by a consideration of the acid, saponification, and acetyl values. Pinus turpentine when added in small quantity to strong ammonia water produces a milky mixture which will set to a jelly when the propor- tion is about 1-5. Venice turpentine, under similar conditions, does not 488 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS distribute itself; the liquid remains clear, and subsequently the turpen- tine is converted into a semi-solid, colorless, opaque mass. Pinus turpentine sets into a hard mass when mixed with 20 per cent of its weight of calcium hydroxide. Venice turpentine does not set immedi- ately when mixed with this reagent. Haarlem Oil This product formerly enjoyed an enormous sale in the United States. It is an old remedy and the genuine Haarlem oil gets its name from the town in which it was first manufactured in Holland. Several formulas, more or less similar, have appeared in the market, all bearing the name Haarlem oil. The original claims for this mixture were about the most far-reaching of any claims that have been attached to any remedy in modern times, and after reading them the patient might believe himself to be the possessor of the panacea of all evil and the golden touch of old King Midas. The principal ingredients were linseed oil, which had been boiled with sulphur, and turpentine. Chian Turpentine The specific gravity is reported 1.050 but varies with the percentage of volatile oil. It is readily and almost completely soluble in the ordi- nary volatile solvents and according to E. Dieterich has acid value d. 47.13- ^8.53;- ester value 19.13-21.47; saponification value, h. 66.26-70.00. Abietic Acid, C20H40O2 Abietic or sylvic acid is the chief constituent of colophony or common rosin, though it has been reported that some samples of authentic identity contained none. Colophony is the anhydrous residue left on the dis- tillation of the turpentine obtained from different trees of the Pinus family. When pure, abietic acid is a white crystalline substance melting 182°, (156-162° Cohn), insoluble in water but dissolving in alcohol, ether, benzol, and glacial acetic acid. When treated with strong ammonia it is converted into a gelatinous mass which dries to a solid resin, readily soluble in water. Copper abietiate is soluble in ether. In analytical work abietic acid is seldom obtained pure, but in admix- ture with the other rosin acids. They are easily removed from ethereal solution by shaking with caustic alkali and then removed from the alka- line liquid by adding excess of acid and shaking out with ether. The ether on evaporation leaves a residue of free acid which can be separated from phenols or any moderately soluble acids if these are present, by washing with boiling hot water. The rosin acids after the above treat- ment can be subjected to the Liebermann-Storch (Storch-Morawski) GUMS AND RESINS 489 reaction. A portion of the residue is dissolved in warm acetic anhydride and after cooling, sulphuric acid (1-1 by volume) is allowed to flow into the solution, producing a reddish-violet color. Kauri resin gives a deep violet-red color changing to brown; amber and East India and black dammar resins, deep wine red changing to brown; Manila, pontianac, and Borneo resins, dark brown, Batavia, and Sing- apore dammar resins, deep wine red which does not change on standing. Some specimens of Manila give a reaction similar to that of abietic acid. The copper acetate test for abietic acid is obtained by dissolving the resin in alcohol, transferring to a separatory funnel and adding an equal volume of petroleum ether. When mixed by agitation, water is added and the whole shaken for thirty seconds. After separating, the aqueous layer is drawn off and the petroleum ether washed with water until both layers are clear. Thirty mils of a J per cent solution of copper acetate are added, shaken and the appearance of a green color in the petroleum ether indi- cates abietic acid. Rosin is used as the adhesive agent in certain forms of plaster and the general directions for handling this class of products qualitatively is given in detail in my work on Qualitative Analysis. One well-known plaster in general use consists of rosin and tartar emetic. If it is desired to determine the latter ingredient, the plaster or a known proportion of it is treated with absolute ether, which dissolves the resin and leaves the tartar emetic behind. The ether solution is filtered off and the container and filter washed with ether, until free of rosin. The tartar emetic is then dissolved in water and the antimony precipitated by hydrogen sulphide and the determination finished as detailed under Antimony. CANADA BALSAM Canada balsam is a clear, pale yellow (almost greenish) and slightly fluorescent viscid liquid, with a pleasing odor and bitter taste, and solidi- fying on exposure to the air. It is completely soluble in chloroform, ben- zol, and acetic ether, largely soluble in ether and oil of turpentine and partly soluble in alcohol and petroleum ether. It solidifies when mixed with magnesia and water. Its acid value is reported from 81.3-86.8; ester value 4.54-13.1; and saponification value, hot 89.43-95.76; refrac- tive index 20°, 1.5194-1.523. Dieterich, quoting Bonastre, gives the composition of Canada balsam as follows: Per Cent Lsevorotatory ethereal oil 18.6 Resin soluble in alcohol 40 . Resin sparingly soluble in alcohol 33 . 4 Caoutchouc 4.0 Bitter principles, extractives, trace of acetic acid 4.0 490 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Tschirch, working on more modern lines, has isolated resinol acids standing in a certain relationship to abietic and pimaric acids. Canada balsam is used in chronic bronchitis and as a stimulant to the mucous surfaces in catarrhal affections. It will be found in some of the prescription remedies recommended for diseases of the throat and lungs. Mixed with collodion it produces a very effective skin varnish. MECCA BALSAM Mecca balsam or balm of Gilead is a terebinthinate-like exudation from Balsamodendron gileadense syn. Commiphora opabalsamum, Bur- suracese, and has been employed in medicine for the same purposes gener- ally as Canada balsam and the turpentines. It contains about 10 per cent of volatile oil and is soluble completely in ether. It is not completely dissolved by alcohol and petroleum ether. The data regarding the action of other volatile solvents are discrepant, but this is probably due to the condition of the samples reported on. Dieterich examined fresh and old resinified meccas and obtained the following data: Fresh Old Acid value 39.84- 39.96 60.77-61.37 Estervalue 101.1-101.39 81.90-82.66 Sapon. value, cold 140 . 94-141 . 35 142 . 67-144 . 03 He observed that when fresh the balsam had a very pale color, highly agreeable aromatic odor, and lower specific gravity than the old, the latter having a turpentine-like odor and was dark brown and viscid. COPAIBA BALSAM Several species of Copaiba and Hardwickia (Leguminosese) yield oleo- resinous exudations extensively used in diseases of the mucous membrane of the genito-urinary organs and in chronic skin diseases such as leprosy and psoriasis. The medicinal copaiba is limited officially to the genus Copaiba and the commercial oleo-resins are obtained from South America, the Brazilian tree, C. langsdorfii being one of the chief sources. C. copallifera of West Africa exudes an oleo-resin closely resembling the South American product, and Hardwickia manii of Africa and H. pimenta of India also furnish drugs which to all intents and purposes answer the description of copaiba balsam. Gurjun balsam, which resembles copaiba, and is often mixed with it, possesses medicinal properties similar to those of copaiba. It comes from several species of Dipterocarpus (Dipterocarpacese) growing in the East Indies. GUMS AND RESINS 491 Copaiba is administered in capsules, pills, and tablets; it is combined principally with oleoresin cubeb, santal wood oil, olive oil, and methylene blue. Other medicinal agents sometimes added to the ordinary copaiba mixtures include turpentine, buchu, matico, Krameria, salol, pepsin, guaiac, ferric citrate, iron and anmionium citrate, and ferrous sulphate. Copaiba resin deprived of its volatile oil is occasionally used medicinally. There are several varieties of copaiba distinguished by names repre- sentative of the countries of their production or the ports of shipment. The chief commercial varieties are the Maracaibo, Maranham, and Para. The former are representative of the type of thick balsams and the latter of the thin. Copaiba consists of from 40-75 per cent of volatile oil and 60-25 per cent of resin. Caryophyllene has been detected in the volatile oil. The peculiar and almost characteristic odor of copaiba is due to the volatile oil, and this odor is generally observed in the breath of a patient to whom the drug has been administered. Copaiba balsam consists of amorphous resin acids, resenes, crystalline resin acids, and volatile oil. The volatile oil will run from 40-75 per cent. The crystalline resin acids have been studied. Para balsam contains para- copaivic acid, C20H32O3, melting 145-148°, soluble in ammonium carbon- ate solution; and homo-para-copaivic acid, CisE^sOs, melting 111-112° and insoluble in anunonium carbonate. Maracaibo balsam contains meta- copaivic acid, CnHieCb or C16H24O3, melting 89-90° C. Illurinic acid has been reported in Maracaibo balsam. It is one of the constituents also of African copaiba. Bitter principles are present in all varieties. The analysis of copaiba has been handicapped because of the uncertainty of the purity of the prod- uct under examination and many of the published reports are therefore unreliable. Adulteration has been practiced with gurjun balsam, olive and castor oils, storax, colophony, turpentine, sassafras oil, paraffin, etc., and often one variety of copaiba is mixed with another. The U. S. Pharmacopoeia specifies that the official oleoresin shall con- tain not less than 36 per cent resin, and shall have an acid value of not less than 28 nor more than 95. It should be soluble in an equal volume of petroleum ether, a further addition of the solvent producing a rlocculent precipitate. The volatile oil distilled from copaiba should not boil below 250° and should have a rotation not less than —70 at 25° C. in a 100-mm. tube. The specific gravity of copaiba runs from .95-.97 in the case of Para and .98-99 in the case of Maracaibo, though old samples of the latter will run slightly over 1. Maracaibo oleoresin is completely soluble in ether, chloroform, petroleum ether, oil of turpentine, and carbon disulphide, and almost completely in 90 per cent alcohol and acetic ether. Para copaiba 492 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS is not as completely soluble in petroleum ether and carbon bisulphide as the Maracaibo, but otherwise shows the same solubility. The examination of a sample of copaiba should include the determi- nation of the constants and reactions prescribed in the Pharmacopoeia, and in addition the saponification and ester values. In order to test the vola- tile oil, a complete separation of this ingredient should be effected by steam distillation, and the separated oil filtered. It would be useless to attempt to determine the boiling-point of the oil by distilling it from the oleoresin directly over a fllame. In order to determine the acid, saponification, and ester values, the procedure recommended by Dieterich will prove advantageous. Acid value, direct, 1 gram of the oleoresin is dissolved in 200 mils of 96 per cent alcohol and titrated with N/2 alcoholic potash in presence of phenolphthalein. The volume of alkali consumed multiplied by 28.08 gives the acid value. Saponification value, cold. One gram is placed in a stoppered 1-liter flask and treated with 20 mils N/2 alcoholic potash and 50 mils petroleum ether (sp. gr. 0.700). After standing for twenty-four hours at room tem- perature, the contents are diluted with 95 per cent alcohol and titrated back with N/2 sulphuric acid and phenolphthalein. The saponification value is found by multiplying the volume (mils) of combined KOH by 28.08. The ester value is found by calculation. The results of the examination of a number of samples of authentic copaibas are tabulated below: K. Dieterich has reported an interesting research where he added known amounts of the well-known adulterants to authentic Maracaibo and Para oleoresins and determined the specific gravity, acid, saponifica- tion, and ester values. He concludes that the added adulterants modify the constants of the normal Maracaibo copaiba in the following manner : 1. Gurjun balsam increases specific gravity, lowers acid value, and raises saponification and ester values. 2. Olive oil reduces specific gravity and acid value, but considerably increases the ester and saponification values. 3. Sassafras oil heightens specific gravity, lowers acid and saponi- fication values, leaving ester value almost unchanged. 4. Oil of turpentine reduces specific gravity, acid value, and saponi- fication value, but considerably increases ester value. 5. Venice turpentine increases specific gravity, acid and saponi- fication values, leaving ester value almost unchanged. 6. Colophony greatly increases specific gravity and acid value. No definite conclusions deducible from ester and saponification values. GUMS AND RESINS 493 © © _"© "© Q Q a « ~ A W H W W W W c3 o3 «u © "© "© * P Q Q > > . • . : . : 6 O -3 M M W M £ O W «o S o OS CO O i-H OS DC CO DC 00 t^ 00 o CO 1^ B3 r^ OS o CM CO OS o o 00 CS> OS OS t^. CO 00 CO t*< o 00 ? ? ? i-H O b- OS OS --H X 494 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS 7. Liquid paraffin reduces specific gravity and acid value, increases ester value, but leaves saponification value about normal. 8. Castor oil reduces specific gravity and acid value, considerably increasing ester and saponification values, like olive oil. 9. Resinified old balsam. The acid and saponification values and specific gravity are greatly increased, analogous to the influence of colo- phony. The effects of adulterants on normal Para balsam may be stated as follows : 1. Gurjun balsam increases the specific gravity, saponification and ester values, and reduces acid values. 2. Olive, castor, and other fatty oils lower the specific gravity and acid value, but considerably increase the saponification and ester values. 3. Sassafras oil heightens the specific gravity, but depresses the acid and saponification values. 4. Oil of turpentine lowers the specific gravity and acid value, but largely increases the ester value. 5. Venice turpentine raises the specific gravity, acid, saponification, and ester values. 6. Colophony raises the specific gravity, acid and saponification values. 7. Liquid paraffin reduces the specific gravity, greatly lowers the acid value, and increases the ester value. Many color tests have been proposed for the detection of adulterants, but practically all have been discarded as unreliable. The U. S. Phar- macopoeia recognizes one reaction for the presence of Gurjun balsam to be applied on the volatile oil, 3-4 drops of the oil distilled from the balsam with steam are treated with 3 mils of glacial acetic acid and 1 drop of freshly prepared sodium nitrite solution (1-10) and underlaid with 2 mils of concentrated sulphuric acid. The acetic layer should not show a pink color. Deussen * claims that the optical rotation of the oil furnishes the most important information. The balsam is distilled with steam as completely as possible; the oil is separated from the distillate, dried with sodium sulphate, filtered and the rotation determined. Oil of Copaiba (Maracaibo or Para) The oil distilled from copaiba oleoresin is a, colorless, yellowish, or brownish liquid, with the characteristic odor of the drug, and a bitter, grating taste. It has a specific gravity 0.900-0.910; (a) D =—7 to 35°; boiling 250-275°; refractive index 1.4943-1.5026 (Evans). 1 Arch. Pharm., 242 ; 1914, 590. GUMS AND RESINS 495 It is not completely soluble in 90 per cent alcohol, but dissolves in an equal volume of absolute alcohol. Deussen states that the specific rotatory power of an oil from an unadulterated Maracaibo oleoresin calculated for a 10 cm. tube should be between -2.5-14°. The oil from Maranham balsam has sp. gr. 0.889-0.90; rotation = — 13° to -21°; refractive index 1.494-1.4992 (Evans). The sesquiterpene caryophyllene, C15H24, has been isolated from the oil and may be separated from the fraction distilling between 250-270° by treatment with glacial acetic acid and sulphuric acid and warming on the water-bath, which throws out the hydrate, C15H25OH, melting 94- 96° C. The hydrate may be freed from the oily material by filtering and then crystallized from alcohol. A volatile oil has been reported from an African copaiba. This prod- uct had specific gravity .917-.918* rotation = +20° 42'. No caryophyllene was obtained. AFRICAN OR ILLURIN COPAIBA This balsam contains from 2-3 per cent of illurinic acid, C20H28O3, melting 128-129° C. This acid is crystalline and strongly laevorotatory («)/>=— 54° 89'. The crystalline barium salt is characteristic and may be obtained when an ethereal solution of the acid is shaken with barium hydroxide solution. A few needles appear in a short time and then sud- denly the whole ether layer is covered with a network of fine needles. The volatile oil from African copaiba rotates the plane of polarized light to the right, thus differing radically from the oils of South American copaiba, which are lsevogyrate. According to the present rulings, the substitution of African copaiba for the official varieties constitutes an adulteration. GURJTJN BALSAM Gurjun balsam has a specific gravity of .955-.979, acid value 5.0-10.98 saponification value 10-26.35, and ester value 1-15.37; most of these values being determined by K. Dieterich. By steam distillation up to 70 per cent of oil are obtained. The odor and taste resemble copaiba. The color is greenish gray; with reflected light somewhat turbid and slightly fluorescent, with transmitted light, clear and reddish brown. The volatile oil is a yellow, somewhat viscous liquid, sp. gr. .915-. 930; («)z>=-35° to 130°. It distills almost completely between 225°-256°. It is not completely soluble in 90 per cent alcohol. Its chief constituent is a sesquiterpene, C15H24, but its identity has not been determined. It is claimed that when taken internally, gurjun balsam imparts no unpleasant odor to the breath. 496 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The chief concern of the analyst is in the testing of the commercial drug and with the data and directions set forth the examination should present no difficulties. The presence of copaiba in a medicine is usually apparent by the odor, though if the resin alone has been used the odor may be faint or even absent. The question then may be. to determine whether the oleoresin or the volatile oil has been used or whether copaiba or gurjun is the medica- ment in hand. Being a complex mixture itself, its complete separation from other ingredients of a compound medicine is practically impossible. If the product under examination contains no great amount of resin- ous matter and the proportional amount of volatile oil in the whole is large, it is quite probable that the oil and not the oleoresin has been employed. If the volatile oil contains caryophyllene and this sesquiterpene can be separated by means of its hydrate or some other derivative and its identity established, and if the absence of clove oil is established, and furthermore, if the volatile oil does not give the color reaction for gurjun, it is safe to assume that copaiba and not gurjun is present. Copaiba is incorporated into pills and tablets in the form of copaiba mass or solidified copaiba, which is obtained by mixing the oleoresin with magnesium or calcium oxide and water. This mass may contain 90 per cent or more of the oleoresin. In pills and tablets the copaiba mass will run from | grain up to 2 or 3 grains. In capsules the oleoresin may run from 3 to 10 minims. No satisfactory method for the determination of copaiba in medicines can be offered. An approximate estimation of the amount present can, however, be made with a fair degree of accuracy by one who has considerable experience with copaiba mixtures, but this is due more to the personal equation and cannot be set down in black and white. AMMONIACUM True or Persian. — Ammoniacum is the gum resin of Dorema ammoni- acum (Umbelliferse) which is a native of Persia, Northern India, and South- ern Siberia. It is used as an expectorant, stimulant, and antispasmodic in chronic catarrh, asthma, and bronchial affections, and is often combined with ipecac and squill in pills and tablets. It also has some reputation as an emmenagogue and diuretic. It is used externally for treating indolent ulcers and white swelling of joints, and is applied in plaster form as a rubefacient for chronic rheumatism. The natural gum-resin consists of 60-70 per cent of acid and neutral resin, soluble in ether, a considerable portion (12-30 per cent) of gum, volatile oil, free salicylic, acetic, and caproic acid, water and vegetable debris. The acid resin is a salicylic ammoresinotannol ester, and the GUMS AND RESINS 497 isolated ammoresinotannol appears to be closely allied to galboresino- tannol. The gum is similar to acacia and yields on hydrolysis galactose, arabinose, mannose, and an acid. Oxidation with nitric acid yields mucic acid and galactose, but not saccharic acid. The volatile oil has n. 1.4747- 1.4808, and give the color reaction with sodium hypobromite described below. This oil has a specific gravity .891 at 150° and melts principally between 250-290°. Its odor is similar to that of angelica. Umbellif- erone and sulphur are not present. Ammoniacum occurs in irregular, rounded tears, yellowish outside and whitish within; opaque, brittle when cold, but soft when warm. It also occurs in masses darker in color and less homogeneous. The odor is peculiar and the taste is sweetish, bitter, and somewhat acrid. The masses contain a large quantity of volatile oil and are greasy, while the tears are solid. The gum resin, owing to its composition, is partially soluble in alcohol and water. African ammoniacum is much darker in color and differs in taste and odor. It differs from Persian ammoniacum in proximate analysis and contains umbelliferone. Adulteration with galbanum and African ammoniacum has been prac- ticed. Other resinous and vegetable material are also used to sophisti- cate the pure product. An alcoholic solution of ammoniacum gives a violet color with sodium hypochlorite and hypobromite. This test being of value in establishing the identity of ammoniacum in medicines and when mixed with other gum-resins. Dieterich records the following constants for commercial ammoniacum : Ash up to 10 per cent. Loss at 100° C, 2.15-12 per cent. Volatile acid value, 100-200. Acid value ind., 90-105. Resin value, 99.4-155.4. Gum value, 7.0-46.2. . Total saponification value, 145.6-162.4. A good ammoniacum shows a high volatile acid value and a low gum value. African Ammoniacum tested by Dieterich showed the following figures: Acid value ind., 47.59-92.21. Resin value, 103.89-104.59. Total saponification value, 105.3-108.1. In general the values are lower than those given by Persian ammoni- acum. Dieterich's Methods for Assaying Ammoniacum. — The drug should be thoroughly chilled and ground in a cold mortar. 498 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Volatile Acid Value. — 0.5 gram is mixed with a little water in a flask, through which a current of hot steam is passed , the flask being heated in a sand-bath. The receiver contains 40 mils of N/2 KOH, into which dips the tube coming from the condenser. Five hundred mils are distilled and the excess alkali titrated back in presence of phenolphthalein. The num- ber of mils of KOH combined, multiplied by 28.08 gives the volatile acid value referring to 0.5 gram. Acid Value Ind. — One gram is boiled under a reflux with 50 grams water for fifteen minutes, followed by 100 grams alcohol for an equal time. After cooling the weight is made up to 150 grams, filtered and 75 grams of filtrate (0.5 gram of substance) are treated with 10 mils of N/2 alcoholic KOH, allowed to stand exactly five minutes and titrated back with N/2 sulphuric acid and phenolphthalein. The number of mils of combined KOH multiplied by 28.08 and referred to 1 gram of the sub- stance gives the acid value. Resin Value and Gum Value. — Two samples of 1 gram each are used. Each sample is treated in a 1000-mil stoppered flask with 50 mils petroleum ether (sp. gr. .700) followed by 25 mils N/2 alcoholic KOH, which is allowed to act in the cold for twenty-four hours, agitation being frequent. One sample is then treated with 500 mils of water and titrated back with N/2 sulphuric acid and phenolphthalein — this gives the resin value. The second sample is treated with 25 mils of N/2 aqueous KOH and 75 mils water and left, with frequent agitation twenty-four hours, then diluted with 500 mils of water and titrated with N/2 sulphuric acid, the result being the total saponification value. The respective quantities (mils) of KOH consumed multiplied by 28.08 gives the corresponding values. The gum value is found by subtracting the resin value from the total saponification value. Test for Galbanum. — Five grams are boiled with 15 mils strong hydro- chloric acid for fifteen minutes, filtered until clear filtrate is obtained and then supersaturated with ammonia. If umbelliferone is present the liquid will show the characteristic blue fluorescence in reflected light. The actual gum present can be determined approximately by dissolving 1-2 grams of the sample in sufficient 60 per cent chloral hydrate solution and pouring into 100-150 mils of 95 per cent alcohol. The precipitated gum is collected on a tared Gooch, washed with alcohol and weighed. GALBANUM Galbanum is the gum-resin of Peucedanum galbanifluum P. rubricaule and allied species of Umbelliferse, indigenous to Persia It is employed medicinally as a stimulant, carminative, and expector- ant, chiefly in chronic affections of the mucous membranes, bronchial, uterine, and vaginal catarrh, and is offered in pill form combined witfi GUMS AND RESINS 499 myrrh and asafetida. Externally it is used as an irritant and mild stimu- lant in plasters. Galbanum consists of from 10-20 per cent volatile oil, 50-67 per cent resin, 15-20 per cent gum, mineral matter and vegetable debris. The resin is soluble in ether and alkalies, and contains about .25 per cent free umbelliferone, galboresinotannol, and about 20 per cent umbelliferone combined with the resinotannol. The volatile oil has an aromatic and not unpleasant odor, yellowish in color, sp. gr. .910-.940 (.908-.955 Harri- son and Self) and is reported as dextrogyrate up to +20° and laevo up to — 10°. n= 1.4863-1.4869. It is reported as containing d-pinene and cadinene, the latter being identified by the preparation of its hydrochloride, melting 117-118°. On dry distillation galbanum yields a blue oil having the odor of chamomile. On fusion the resin yields resorcin and an acid. Galbanum occurs in agglomerated tears or masses, grayish yellow or greenish, with a wavy luster. The odor is balsamic and the flavor bitter, acrid, and burning. It is partially soluble in water, alcohol, and ether. When boiled with hydrochloric acid, filtered, and supersaturated with ammonia, a blue color, due to umbelliferone, appears. Galbanum is often adulterated with ammoniacum, turpentine, fatty oils, sand, exhausted galbanum, and vegetable material. Dieterich's researches on galbanum showed the following constants: Volatile acid value, 73.5-114. Acid value ind., 21.24-63.45. Resin value, 107.5-122.5. Total saponification value, 116.2-135.8. Gum value, 8.4-16.1. Ash, 8.4-16.1 per cent. Loss at 100°, .35-31.5 per cent. Galbanum should be assayed by the methods described for Ajnmoni- acum. The quantity of the gum is determined by the precipitation of a chloral hydrate solution with alcohol. Dieterich concludes that adulteration with ammoniacum decreases the volatile acid value, while asafetida has the reverse effect. Asafetida is readily detected by the characteristic odor during distillation. The indirect acid value is raised by ammoniacum but is reduced by asafetida. The presence of ammoniacum is indicated by the color reactions given with sodium hypochlorite and sodium hypobromite. GAMBOGE Gamboge is a yellow gum resin from Garcinia morella (Clusiacese) indigenous to Siam and Ceylon. It is a valuable cathartic and is often found in combination with other drugs in remedies for obstinate constipation, intestinal torpidity and 500 GLUCOS1DES, GLUCOSIDAL DRUGS AND NATURAL DRUGS hepatic troubles. The U. S. P. compound cathartic pills contain gam- boge, jalap, colocynth comp. and calomel; other pill formulas consist of gamboge with aloes, Podophyllum, Capsicum and croton oil; with colo- cynth comp., jalap, ginger, rhubarb, and calomel; with jalap, Leptandra, aloin, Podophyllum, Capsicum, Hyoscyamus, peppermint; with aloes, colocynth, soap, and anise; with Veratrum viride, croton oil, aloes, jalap Podophyllum, Capsicum, and Leptandra. Gamboge consists of resin, gambogic acid, gum, wax, and vegetable debris. The resinous material amounts to 75-82 per cent, the gum about 16 per cent. No volatile oil is present. It occurs in the trade in the form of pipes, cakes, lumps, and powder. The color is reddish yellow and the dry lumps have a chonchoidal lustrous fracture. It floats on carbon bisulphide at a temperature of 20° C. but sinks at higher temper- atures. It is soluble in alkalies, and 60 per cent chloral hydrate, forms a yellow emulsion with water, partly soluble in alcohol, ether, and other volatile solvents. Gamboge is often adulterated with colophony and in the powdered form was formerly almost never found free from admixture with starch. Other impurities consist of sand, dirt, dextrin, turmeric, and Taylor reports an instance of dangerous sophistication with lead chromate. Starch is almost always present in small quantity in powdered gamboge which is otherwise pure and the reason for the presence of minute quan- tities which can hardly be considered as intentional adulteration is not apparent. The mineral matter (ash) of pure gamboge should not exceed 1 per cent. Starch may be detected by boiling some of the powdered drug with water, cooling, and adding iodin. A faint-green color will often appear at this juncture, but any color darker than this indicates adulteration. Eberhardt recommends boiling 1 gram of the powdered material with 5 per cent potassium hydroxide solution, neutralizing with acid, filtering, and testing the nitrate with iodin. There are certain advantages to the last procedure as the blue color of any starch iodide formed is not altered by the yellow pigment of the gum-resin; 2 per cent or over of starch will yield a blue precipitate. Good gamboge should contain not more than 25 per cent of material insoluble in 95 per cent alcohol. Taylor 1 determines both the alcohol-soluble portion of the gum resin and the acid value with one sample. Two grams of the powdered sample are digested with heat under a reflux condenser with exactly 150 mils 95 per cent alcohol for not less than fifteen minutes, the solution cooled and 75 mils (representing 1 gram of the resin) filtered off through a dry tared filter. This 75 mils is used for titration of the acid value, which is 1 J. Ind. and Eng. Chem.. 1910, II, 208. all pure gamboges GUMS AND RESINS 501 made direct on this solution, and the nitration is continued so that the insoluble residue may be finally collected in the filter and weighed. The acid value titration gives results agreeing with those obtained by Dieterich's method. The acid value runs from 80-96 and this value varies in direct propor- tion to the alcohol solubility with few exceptions. In other words* a high alcohol solubility usually accompanies a high acid value. Some of Taylor's figures illustrative of this relationship are appended. Acid Value Alcohol Solubility 95.8 84.0 91.6 79.05 88.6 82.0 85.8 77.4 85.8 77.0 81.6 74.9 80.2 76.15 80 . 5 52 . 95 starch adulterant 67 . 7 57 . 6 colophony adulterant 67 . 7 613 colophony adulterant Dieterich's method for determining the resin value and total saponi- fication value: Two 1-gram samples of finely triturated gamboge are each covered with 25 mils N/2 alcoholic KOH and allowed to stand tightly stoppered for twenty-four hours. One sample is then diluted with water and titrated, the volume of the KOH consumed multiplied by 28.08 giving the resin value. The second sample is then treated with 25 mils N/2 aqueous KOH, allowed to stand twenty-four hours longer and titrated, the result giving the saponification value. The gum value is obtained by difference. Dieterich found the resin value to run from 105-116.2; the total saponification value from 121.8-138.6, the gum value from 14-22.4 The percentage of gum may be determined by Mauch's method. The sample is dissolved in 5 parts of 60 per cent aqueous chloral hydrate, pre- cipitated by alcohol, and the gum collected on a tared Gooch, washed with alcohol and weighed. LACTUCARIUM Lactucarium is the dried milky juice of Lactuca virosa (Compositse) and other species of Lactuca. It is obtained by cutting off the tops of the stems and when the latex which exudes is partially hardened, it is collected and dried in hemispherical earthen cups until it can be cut into pieces and which are usually four in number, these being further dried. It occurs in commerce in irregular, angular pieces or quadrangular sectors, one surface of which is convex, externally dull reddish or grayish 502 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS brown; fracture tough, waxy, internally light brown or yellowish, some- what porous, odor distinct and opium-like, taste bitter. It is partly soluble in alcohol, ether, chloroform, and water. Three bitter principles are reported as occurring in lactucarium, lac- tucin, which occurs in white rhombic prisms, sparingly soluble in water; lactucopicrin, a brown, amorphous, very bitter principle which is readily soluble in water and alcohol; and lactucic acid, a yellow, very bitter substance crystallizing with difficulty and colored red by alkalies. It contains also about 50 per cent of a colorless, odorless, and tasteless crys- talline substance, lactucerin (lactucon) ; a- and /3-lactucerol in the form of acetates, volatile oil, mannitol, organic acids, citric, malic, and oxalic. The principal use of lactucarium is in a certain class of anodyne syrups recommended for infants. It may be combined with opium in these remedies. It also enters into the composition of some syphilitic pills with mercurous iodide, opium, and Conium. The commercial varieties include German and English lactucarium and Lactucarium Gallicum from L. sativa, the " Thridax " of ancient days. German lactucarium forms tough, homogeneous, yellow-brown masses, somewhat waxy in fracture and hygroscopic. The English drug consists of irregular, larger, and smaller granules, more or less obtuse angled, dull, friable, dark brown in color and non-hygroscopic. Gallicum is a blackish- brown fatty extract. Lactucarium is adulterated with farinaceous material, vegetable extracts, and colophony. The important constants of lactucarium are determined by Dieterich as follows: Two 1-gram samples of the powdered drug in stoppered liter flasks are covered with 50 mils petroleum ether (sp. gr. .700) followed by 25 mils N/2 alcoholic KOH, and allowed to stand for twenty-four hours with frequent shaking. One sample is then diluted with 500 mils of water and titrated back with N/2 sulphuric acid, the results giving the resin value. The second sample is further treated with 25 mils of N/2 aqueous KOH and 75 mils water and allowed to act with occasional agitation twenty-four hours longer. It is then diluted with 500 mils of water and titrated back with N/2 sulphuric acid, the results giving the total saponification value. The gum value is determined by difference. For German lactucarium in mass Dieterich found resin value 154- 156.8; total saponification value 166.6-169.4; gum value 12.6. High resin and saponification values indicate adulteration with colophony which should be tested for by the Storch-Morawski reaction. The results Dieterich obtained on the English drug indicated irregular composition; resin value from 50.4-225.4; saponification value 75.6- 238; gum value 7-26.6. It is probable that the excessively high data GUMS AND RESINS 503 for resin and saponification values were obtained with sophisticated products. MYRRH AND ITS ALLIED GUM RESINS. (HERABOL MYRRH) Myrrh is the dried emulsion-like juice which exudes from several species of Commiphora and Balsamodendron (Burseracese), native in the coast districts of the Red Sea such as the Somali coast of East Africa, in Arabia, and probably Persia. From the interior of the Somali lands there comes a variety of myrrh (bisabol) which has been ascribed to Baisamea erythrea, belonging to the same family, and which has been considered identical with commercial opopanax. The latter drug occurs in two varieties, the burseraceous and umbelliferous, the former being found in the trade, and its source has been ascribed to the species Balsamoden- dron kafal. As a matter of fact the botanical origin of these gum resins has not been traced with entire satisfaction and any statements regard- ing the species yielding the burseraceous gum-resins must be taken with reserve. Herabol myrrh is the usual commercial grade. It has a wide and varied use in medicine, for besides being a valuable constituent of mouth washes, tooth powders, and applications for spongy gums and sore throat, it is a stimulating tonic with apparently some influence on the lungs and uterus and is found in female pills, liquid aloes mixture, expectorants, etc. Myrrh is combined with aloes and licorice in fluid compounds of aloes, and also with Capsicum. It also accompanies aloes in many different pill formulas. Female pills contain myrrh, aloes, ferrous sulphate, helle- bore, ginger, soap, and Canella. Other formulas containing myrrh include asafetida and galbanum; rhubarb, aloes, soap, and peppermint; aloes and mercury mass; aloes, scammony, croton oil, and caraway. Warburg tincture contains myrrh. Astringent mouth washes contain myrrh com- bined with glycerin and mild antiseptics and aromatics. Tooth powders often contain myrrh. Griffith's mixture, the compound iron mixture, consists of myrrh, ferrous sulphate, sugar, potassium carbonate, and flavors. The volatile oil of myrrh is employed as a remedy for bronchitis. Plasters contain myrrh, camphor, Peru balsam, and lead oleate. Herabol myrrh occurs in the form of masses and granules, yellowish red in color, with a greasy, lustrous, fine-grained fracture. It has a strong and characteristic odor and a bitter acrid taste. If forms a milky emul- sion with water and alcohol dissolves the resinous portion. This drug is the so-called " male myrrh." It consists of 50-75 per cent of gum; 2.5-8 per cent of volatile oil, 20 per cent or more of resin. The presence of a bitter principle has been reported. The resin is a complex mixture containing neutral resin and resinous acids. The volatile oil has sp. gr. .988-1.007; (a) D =— 67° to —90°, and its solution in petroleum ether is 504 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS colored red by bromine vapors, a test which distinguishes this variety of myrrh from Bisabol myrrh and bdellium. The ash should not exceed 8 per cent. Myrrh is adulterated with Bisabol myrrh, bdellium, gum arabic, and extracted myrrh resin. If Herabol myrrh is treated with petroleum ether (1-15), and six drops of the clear extract are mixed with 3 mils of glacial acetic acid and floated on the surface of 3 mils of concentrated sulphuric acid, the acetic layer develops a very pale rose color which does not increase in strength, and the surface of contact between the two layers shows at first a green color which turns brown with a green fluorescence on standing. With Bisabol myrrh a rose red zone immediately forms at the surface of contact and the coloration soon extends throughout the entire layer of acetic acid and remains persistent. Dieterich gives the following methods for determining the constants of myrrh: Acid Value. — One gram of the finely powdered nryrrh is treated with 30 mils of distilled water and warmed for fifteen minutes under a reflux, 50 mils of 95 per cent alcohol are added and the boiling repeated for fifteen minutes. After cooling the liquid is titrated with N/2 alcoholic KOH and the volume of alkali consumed multiplied by 28.08 gives the acid value. Saponification Value. — One gram of the sample is treated with 30 mils of water, allowed to stand one-half hour, treated with 25 mils N/2 alcoholic KOH and boiled for one-half hour under a reflux on the steam-bath. After cooling and diluting with alcohol it is titrated back with N/2 sulphuric acid, the volume of alkali consumed multiplied by 28.08 gives the saponification value. Ester Value. — This is found by difference. Alcohol Soluble. — Determined by extracting the sample with 95 per cent alcohol in a thimble in a Knorr or Soxhlet apparatus and weighing the undissolved portion. Dieterich reports the following values for myrrh and the allied gum- resms. Acid Value Ester Value Saponification Value Solubility in Alcohol, Per Cent Herabol myrrh 25.48 204.12 229 . 60 20 Bisabol myrrh 20.06 125.54 145.60 50 African bdellium .... 9.73-20.8 70-96 82-111 Indian bdellium 35.6-37.19 46.75-48.46 82.44-85.65 Burseraceous opopanax 10.46-30.92 81.94-97.24 96.20-152.82 Umbelliferous opopanax 32.43-58.57 105.46-142.6 137.S9-199.07 GUMS AND RESINS 505 The percentage of gum in myrrh is determined by Mauch's method. One to two grams of the sample are dissolved in 10-15 grams of 60 per cent aqueous chloral hydrate and precipitated with 100 grams 95 per cent alcohol. The precipitate is collected on a tared Gooch, washed with alco- hol, and weighed. Bisabol myrrh contains a much smaller percentage of gum and a larger quantity of resin than Herabol myrrh. It contains a bitter principle, water, volatile oil, and vegetable debris. The resin contains free acids, a resene, and a neutral substance. This drug is known as " female myrrh." BDELLIUM African bdellium is probably derived from Commiphora africana, and East Indian bdellium from Balsamodendron indicum (Burseracese) . The African drug is in reddish oval or round lumps about J inch across, which have a greasy luster, and become soft and plastic when warmed. East Indian bdellium is in the form of shapeless agglomerated lumps about one inch in diameter, externally rough, uneven, dull, of a dark-brown color, a lustrous fracture, a sharp, bitter flavor and an odor resembling Bisabol myrrh. Bdellium furnishes a white emulsion with water like myrrh. It does not give the characteristic color reactions of myrrh with bromin vapor and its analytical constants are different. Our interest in the drug is chiefly on account of its being used as an adulterant of myrrh, and the methods of examination are precisely the same as detailed under that drug. Indian bdellium is employed in the East as a remedy for leprosy, syphilis, and rheumatism. OPOPANAX There are two distinct varieties of this gum-resin, one derived prob- ably from Balsamodendron kafal (Burseracese) of Persia and the other from Cheronium opopanax (Umbelliferse) of Southern Europe. The Burseraceous gum-resin consists of about 19 per cent of resin, gum, and vegetable debris up to 70 per cent, volatile oil 6-10 per cent, and moisture. The resin consists of a-panaxresene (C32H54O4); /3-pan- axresene (C32H52O5) ; panaxresinotannol (C34H50O8) ; an alcohol, chironal (C28H48O), and bitter principle. The oil has a greenish color and a pleasant balsamic odor. It resinifies readily on exposure to air, specific gravity 0.870-0.905; (a) D — 10 —12°. With bisulphite solution a brownish mass separates from the oil, which on sublimation yields white needles melting 134-134°, to which the name oponal (C20H10O7) has been given. This variety of opopanax is commonly designated as myrrh in the East and according to Holmes may probably be the myrrh of the Scrip- tures. Its odor is peculiar, resembling Sumbul and Bisabol myrrh. It 506 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS occurs in large, brown yellow lumps with paler gummy granules and smaller white lumps. The chemical constants have been recorded under myrrh and may be determined by the same methods. Umbelliferous opopanax has a strong disagreeable odor and balsamic taste. An analysis showed 51.8 per cent ether-soluble resin (ferulic acid ester of oporesinotannol) ; 19 per cent ether-insoluble resin; 33.8 per cent gum; 8.3 per cent volatile oil, small quantities of ferulic acid, and vege- table residues. It occurs in greasy masses or brownish yellow lumps. ASAFETIDA This gum resin is a product of several species of Ferula (Umbellif- erse) the ninth revision of the U. S. P. designating F. asafetida and F. fetida as the chief sources. J. Small, who has examined the botanical sources of the fetid gum resins, assigns the white asafetida to F. rubri- caulis and the red variety to F. fetida. Asafetida is a component of sedative mixtures and remedies for whoop- ing cough, chorea, chronic bronchitis, hysterical affections, convulsions, flatulent constipation, asthma, and catarrh. It is sometimes dispensed in liquid form, but more often in pills or tablets. Sedative mixtures will consist of asafetida with sumbul, valerian, ferrous sulphate, and arsenous acid. It will be found combined with aloes and soap; with opium and ammonium carbonate; with Nux Vomica; with reduced iron and rhubarb; and with myrrh and galbanum. Asafetida is very exten- sively employed in veterinary practice especially in remedies for " heaves." At the time the Food and Drugs Act went into operation probably there was no imported drug which was so flagrantly adulterated as asafetida. The Pharmacopoeia had prescribed a standard for the drug but no atten- tion w T as paid to the requirements except by a few progressive manufactur- ing pharmacists. In general the importer paid little attention to the quality of the drug. The change in conditions after January 1, 1907, caused a storm of protest from the importers of asafetida, anl it was some time before the authorities could convince them that the standards of the Pharmacopoeia were reasonable, and were based on the examination of specimens of known purity. At that time the asafetida was adulter- ated with sand, gravel, and broken lumps of mineral matter, and the ash frequently ran over 50 per cent. Other gums and gum resins, gal- banum, African ammoniacum, rosin, and turpentine were also used, and after the more easily detectable mineral matter ceased to be a source of trouble, the sophistication with other resinous material persisted and still does. A peculiar gum resin of uncertain origin, known to the trade as pepper GUMS AND RESINS 507 asafetida, should not be mistaken for the official drug. Its odor is similar when cold, but on heating a pungent, peppery odor develops which is not characteristic of true asafetida. The lead number is low, 82. Asafetida consists of about 62 per cent of the ferulic acid ester of asaresinotannol, small amounts of free ferulic acid and asaresinotannol, about 25 per cent of gum, 3-17 per cent of volatile oil, a trace of vanillin, moisture, and mineral matter, the latter amounting to not over 10 per cent in a good crude drug. The steam-distilled oil possesses the disagreeable, alliaceous odor of the drug. It has specific gravity .975-.990; n 1.4942-1.5250; (a) D -9° 15' (Gildermeister and Hoffman), -35° 55' to +9° 39' (Harrison and Self). It contains two terpenes, one identical with pinene, and several sulphur compounds which * were fractioned by Semmler, and found to be a disul- phide C7H14S2, boning 83-84° at 9 mm.; sp. gr. 0.9721 at 15°; (o:)z>-12 30', comprising about 45 per cent of the crude oil. A disulphide, CiiH 20 S 2 , sp. gr. 1.0121; boiling 126-170° at 9 mm.; {a) D — 18° 70', comprising 20 per cent of the oil and being the cause of the repulsive odor of the drug. A substance (Ci Hi 6 O)ri, sp. gr. .9639 at 22°; boiling 133-145° at 9 mm.; {a) D — 16° present to the amount of 20 per cent and yielding cadi- nene, C15H24, on treatment with sodium. A compound, C 8 Hi6S2, boiling 92-96° under 9 mm. A disulphide, Ci Hi 8 S 2 , boiling 112-116°. Harrison and Self consider this oil, and especially its sulphur content, an important factor in the valuation of the drug and their method of procedure is subsequently described. Pure asafetida will show acid value 65-80, ester value 80-130, saponi- fication value 120-185, lead number 200 up, ash 1-10 per cent. Analysis of Asafetida. — It is important to obtain a fair average sample of a lot of asafetida and poor sampling is usually the cause of divergent results in cases of contest. Several drawings should be made from a package and these thoroughly mixed and if possible run through a sausage grinder to ensure homogeneity. Alcohol Soluble. — Introduce about 10 grams of asafetida into a tared, 250 Erlenmeyer flask, determine the exact weight of the drug, add 100 mils of alcohol, and having connected the flask with an upright condenser, boil the mixture in the flask during one hour or until the drug is completely disintegrated. Then transfer the contents of the flask to two counter- poised, plainly folded filters, one within the other, so that the triple fold of the inner filter is laid against the single side of the outer, and wash the flask and filter with consecutive, small portions of boiling alcohol until the washings no longer produce a cloudiness when dropped into water. Collect and reserve the mixed alcoholic solutions, for the qualitative tests 508 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS given below. Dry the niters and flask to a constant weight at a temper- ature of about 115° C. Now determine the weight of the residue on the filter and in the flask and calculate its percentage from the amount of asafetida originally taken. This percentage of alcohol-insoluble material, when subtracted from 100, gives the percentage of alcohol-soluble con- stituents contained in the asafetida. Acid Value. (Dieterich). — One gram is treated with 10 mils each of N/2 alcoholic and aqueous KOII, and left to stand in a stoppered liter flask for twenty-four hours at room temperature. After dilution with 500 mils of water, the whole is titrated back with N/2 sulphuric acid. The volume of KOH consumed multiplied by 28.08 gives the acid value. Saponification Value. (Dieterich) . — One gram is treated with 25 mils N/2 alcoholic KOH and boiled for one hour under a reflux. At the end of that time 200 mils of alcohol are added and when cold the whole is titrated back with N/2 sulphuric acid. The volume of KOH consumed multiplied by 28.08 gives the saponification value. The ester value is determined by difference. Gum Assay. — One to two grams of the sample are dissolved in 10-15 grams of 60 per cent chloral hydrate filtered from mineral matter, the filter washed with the reagent and the gum precipitated by pouring the mixture into 10 parts of 95 per cent alcohol. The precipitate is collected on a tared Gooch, washed with alcohol, dried and weighed. Ash Determination. Mauch's Method. — The sample is treated with ten to fifteen times its own weight of 60 per cent chloral hydrate solution, filtered onto an ashless filter, washed with chloral hydrate solution followed by alcohol, dried and ignited. Determination of Sulphur in Asafetida Oil. — Harrison and Self 1 determine the amount of sulphur in the volatile oil and refer the figure thus obtained to the amount of real gum resin in the drug. Therefore, account must be taken of the ash content. They claim that the amount of sulphur should not be below 1.5 per cent on the gum resin basis and may run to 4.04 per cent. A weighed amount of the drug is subjected to steam distillation and the oil collected. The oil is separated and dried, 0.5 gram is weighed into a flask of 150 mils capacity fitted with a ground-in condenser; 5 mils of water are added, followed by 5 mils of nitric acid, sp. gr. 1.42. The flask is gently warmed to start the reaction, 3 grams of potassium bromide are then added, the whole boiled for ten minutes, cooled and treated with 5 grams of sodium hydroxide dissolved in a little water. The contents of the flask are evaporated to dryness and ignited in a platinum crucible. After dissolving in water, the nitric and nitrous acids are boiled off and the sulphur determined by precipitation with barium chloride in presence 1 Pharm. J., 1912, 88, 205. GUMS AND RESINS 509 of hydrochloric acid. A blank determination with materials used must also be made. If there is a large percentage of volatile oil and a small percentage of sulphur the presence of terpenes is indicated. Admixture of galbanum, olibanum, and ammoniacum lower the percentage of sulphur in the gum resin as these drugs contain no sulphur in the oil. Volatile oil of ammoni- acum has n. 1.4747-1.4808, and as an adulterant would lower the oil con- tent. Galbanum has n. 1.4863-1.4869, 1.4840 (Sechler and Bechu), elemi has n. 1.4869. Both galbanum and elemi would lower the sp. gr. of oil of asafetida and increase the dextro-rotation, therefore decreasing the laevo- rotation. Galbanum contains umbelliferone, which can be detected by the blue fluorescence produced by alcoholic ammonia. Asafetida yields the blue fluorescence after boiling with hydrochloric acid, but olibanum and ammoniacum do not. LEAD NUMBER. (E. C. MERRILL) This method was proposed by H. A. Seil and was developed by Merrill and reported in the Journal of the A. 0. A. C, Vol. II, No. 1, page 83. Use a sample (about 20 grams) sufficient to furnish between 5 and 10 grams of the ether purified resin. Determine the alcohol insoluble material in the usual manner. Transfer the first 2 filtrates, representing the major part of the sample, to a casserole or a flat-bottomed porcelain dish, and evaporate the alcohol on the steam-bath. Treat the resinous mass with ether (sometimes it is necessary to warm gently to facilitate solution of the resin). Filter the ethereal solution into a separatory funnel and wash with water until the aqueous layer separates without any milkiness. (If the ether solutions persist in remaining turbid, more ether may be added, or it may become necessary to dry the ether solution by shaking with sodium chloride in the separatory funnel after as much as possible of the aqueous solution has been removed.) Then filter the ethereal solution through a folded filter paper, moistened with ether, into a flask or beaker, and evaporate the solvent on the steam-bath. Determination. — (The residual ether purified resin from the above preparation is now in a state where it can usually be broken up when cold, and powdered.) Into a small tared beaker (about 75-mils capacity) weigh roughly about 1.1-1.2 grams of the resin prepared above and dry for five hours in the air-bath at 110° C. Place in a desiccator, cool, and weigh. (The weight noted is to be used in subsequent calculations.) Dissolve in 20 mils of 95 per cent alcohol, boil gently until the resin is in solution, trans- fer to a 100-mil graduated flask, wash the beaker with hot 95 per cent alcohol, care being taken that the final volume does not exceed 70 mils. 510 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Add 25 mils of the alcoholic lead acetate, agitate and allow to stand overnight. Make up to the mark with 95 per cent alcohol, shake well, allow to stand a few minutes, and then filter through a fluted paper and pipette an aliquot of 25 mils from the filtrate into a beaker. Add 10 mils of water and evaporate to 10 mils. Add 5 mils of 10 per cent sulphuric acid and then 100 mils of alcohol, stirring vigorously to dissolve any separated resin, and heat if necessary. Allow to stand for an hour, then filter the lead sulphate on a tared Gooch, wash with alcohol and finally with ether, dry at 100° C. to a constant weight and weigh. Run a blank on the alcoholic lead acetate solution, and calculate the amount of metallic lead absorbed by 1 gram of the dried resin. The mg. of lead per gram of sample represent the lead number. The factor for the conversion of lead sulphate to metallic lead equals 0.6830. x The lead numbers of a number of authentic resins and gum resins determined by Merrill showed asafetida 222, galbanum 4, ammoniacum 75, olibanum none, guaiac 171, myrrh 7, colophony 142, bdellium 55, sandarac 251, mastic 34, gamboge 9. dragon's blood, none, euphorbium 34, pepper asafetida 82. Qualitative Test for Colophony (Merrill). — For this test Merrill recommends using about 40 mils of the alcoholic solution obtained in determining the alcohol-soluble matter. Transfer to a separatory funnel, add 30 mils petroleum ether, mix, add 50 mils of water and shake for thirty seconds. After separating, discard the aqueous milky layer. Wash the petroleum ether layer with water until the wash water and petroleum ether are both clear. Add 30 mils of 0.5 per cent copper acetate solution and shake well. No green color should appear in the petroleum ether. The appearance of a green color indicates the presence of foreign resins. SAGAPENUM This gum resin is derived from a botanical source not yet satisfactorily identified but belonging to the Umbelliferse. It contains a volatile oil containing sulphur compounds, and its odor recalls both asafetida and galbanum. It contains a considerable portion of resins soluble in ether which has been found to consist of free umbelliferone and umbeiliferone- sagaresinotannol ester. Its ethereal solution gives a red-violet color with hydrochloric acid. Like galbanum it gives the umbelliferone reaction. 1 For the preparation of alcoholic lead acetate dissolve 5 grams of normal lead ace- tate in 20 mils of water and add 80 mils of 95 per cent alcohol. A turbidity generally results, due to the precipitation of lead carbonate caused by carbon dioxide in the alcohol. Allow the solution to stand overnight. The clear, supernatant liquid can then be used without filtering for the determination of the lead number. The blank on 25 mils of alcoholic lead acetate solution should be equivalent to at least 1 gram, calculated as PbS0 4 . GUMS AND RESINS 511 Its assay may be conducted by the procedure given under Myrrh and Dieterich has obtained the following values: Acid value, 13.96-14.81. Ester value, 31.29-39.37. Saponification value, 45.25-54.18. RUBBER AND CHICLE A detailed consideration of the chemistry of rubber and its uses is not within the scope of this work, but reference will be made to its composition and general characteristics for it will be encountered in testing plasters and chewing gums where it often functionates as a basic component. In connection with rubber it is in order to discuss the characteristics of chicle, the chemistry of which is alhed to that of rubber. The sources of rubber and chicle, as well as gutta percha and balata, are the milky juices or latices of a number of different trees, shrubs, and vines. The latices consist of watery emulsions holding in suspension minute globules of material, which coagulate under proper treatment and produce the commercial articles. The coagulated materials consist chiefly of hydrocarbons and resins with more or less carbohydrates, gums, proteids, tannins, mineral sub- stances, coloring matter, and water. The resinous constituents may be oxidation products of the hydrocarbons as it has been found that when the pure hydrocarbons are separated and purified, they take up oxygen with ease. The fundamental hydrocarbons are multiples of C10H16, and the hydro- carbons separated from all four sources are apparently closely alhed, if not identical, that from rubber is designated caoutchouc, that from gutta percha as gutta and the corresponding hydrocarbons from balata and chicle are termed bala-gutta and chicle-gutta. The latex yielding rubber is secreted by many different botanical species representing several families among which may be mentioned the Euphorbiaceas, Urticacess, Apocynacese, and Asclepiadaceae. Gutta percha, balata, and chicle are obtained chiefly from latices of species of the Sopotacess. Raw or unvulcanized rubber is soft, pliable, and elastic, at the ordi- nary temperature. When heated with boiling water or by mechanical working it becomes still softer. It is insoluble in water but is capable of absorbing up to 25 per cent of its own weight. It is insoluble in abso- lute alcohol but forms solutions with chloroform, benzol, toluol, carbon tetrachloride, carbon bisulphide, petroleum distillates, etc. Crude rubber contains a substance insoluble in the ordinaiy rubber solvents but which appears to swell up when subjected to their actions. 512 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS The rubber hydrocarbon is attacked by the halogens and other oxidiz- ing agents. The oxidation product with ozone is a viscid substance which solidifies to a glassy explosive solid. CHICLE This coagulum from the latex of Achras Sapota is usually called gum chicle which is technically a misnomer, as the product comes under the class of gum resins and the resinous portion predominates. It forms a tenacious, firm, aromatic, and elastic mass, white or reddish in color. The red color sometimes develops when the latex is over- cooked in the process of concentration, but this is not always the case as some trees yield a gum-resin with a distinctly red color. Reports of the composition vary. Dieterich found 75 per cent resin, 10 per cent gum, 9 per cent calcium oxalate, 5 per cent sugar and organic salts. Berry 1 states that the resins run from 35.6-55.78 per cent, hydro- carbons 10.39-13.84 per cent. He separates the resins into two groups, resin A insoluble in cold absolute alcohol, saponification value 129; and resin B soluble in cold absolute alcohol, saponification value 100.8. He found the saponification value of the combined resins to be 101.7-104. Acid value slight. Taylor reports an acid value of 52, no ethers or esters, 0.2 per cent ash, 82.7 per cent soluble in chloroform and 84.7 per cent soluble in benzol. Tschirch, 2 in his systematic manner, has examined chicle and reports 16.8 per cent soluble in boiling water, 59.7 per cent in boiling alcohol, 61.7 per cent in boiling acetone, 76.2 per cent in boiling ether, and 77.2 per cent in chloroform. He treated chicle successively with boiling water, boiling alcohol, and chloroform, and examined the fractions. The water soluble portions yielded 9 per cent of gum. In the alcohol-soluble portion was found a-chiclalban, C24H40O, melting 219-221°; /3-chiclalban, CigHsoO or Ci 7 H 28 0, melting 158-159°; 7-chiclalban, C15H28O, melting 86-87°; and chicla- fluavil, CioHigO or C10H20O, melting 66-67°. In the chloroform portion was the hydrocarbon chiclagutta, C10H16 or CioHis, and chiclalbanan, an oxidation product, melting 55-57°. CHEWING GUM The principal components of chewing gum are chicle or some substi- tute, glucose, caramel, sugar, and flavor. Starch is often present in small quantity, as it is used in dusting the gum sheets to prevent their sticking to the rolls. 1 Jour. Soc. Chem. Ind., 1904, 529. 2 Arch. Pharm., 1905, 243-378. GUMS AND RESINS 513 Substitutes for chicle often comprise the base of chewing gum. They are usually prepared by mixing low-grade rubber, the resinous constitu- ents of crude rubber, gutta percha, or balata, the resene portions of other resins such as dammar, and vegetable wax or paraffin. Cauchillo gum is used as a masticatory similarly to chicle, and has been sold quite extensively to chewing gum manufacturers. It is of uncertain origin, but is reported to be derived from a tree in South America. It resembles chicle in physical appearance and is often denominated as chicle in the trade. Chewing gums are medicated with pepsin and to a lesser extent with strychnin or some other bitter substance. The latter type of product is used for the purpose of breaking up the tobacco habit. Occasionally one will meet with unusual mixtures having a chewing gum base, as instanced by one containing a large percentage of coca leaf and which was quite extensively sold several years ago. A complete analysis of a gum includes determinations of the propor- tional amounts of the base, sugars, and medicament, a test for digestive power, the amount of moisture and other volatile components, and ash. As a general thing the drug analyst is concerned only with the medicinal constituents, and in the case of pepsin gums it is often only a question of determining whether or not the sample will act on coagulated egg albumin. For the analysis several sticks of the sample should be broken up into small pieces and thoroughly mixed. The moisture and volatile matter are determined with a 1-2 gram sample, drying at 100-110°. The residue is ignited and weighed as ash. Good chicle gum leaves an ash consisting chiefly of calcium carbonate, no sand or other gritty material being present. To prepare a sample for determining the sugars, etc., about 5 grams are transferred to a flask or stoppered bottle, covered with chloroform and shaken until the resinous ingredients have dissolved. The solution is filtered, the insoluble substance washed with chloroform and then allowed to dry. The dry residue is digested with cold water, and filtered from any insoluble material. Solution may be hastened by transferring as much as possible to a small mortar and grinding the material in the pres- ence of the solvent. The solution is finally made up to a definite volume and the sugars determined in the usual way. An aliquot of the solution is then adjusted to the proper strength with hydrochloric acid, added to a bottle containing a weighed amount of egg albumin and a pepsin test conducted as described in the chapter on " Diges- tives." If digestive agents other than pepsin are suspected the appro- priate procedure will necessarily follow. If strychnin salts or those of other alkaloids are present they will be found principally in the aqueous solution though some portion will go into the chloroform. The alkaloids are freed from the aqueous solution 514 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS by making alkaline and shaking out with chloroform. From the chloro- form solution containing the gum base, any alkaloids can be separated by shaking out with a little normal sulphuric acid and then removed from the acid by making alkaline and shaking out with chloroform. F. J. Andress 1 employs a scheme for testing the gum base in which he masticates a weighed sample until the sugar and flavor have disappeared, dries it in an oven and then weighs. The procedure then goes ahead as follows : Weigh off a 2 or 3-gram sample in an alundum extraction thimble, using a small cotton plug to close up the open end. Extract with acetone in a Soxhlet apparatus for five or six hours. Allow the extraction to proceed until the acetone becomes colorless as it siphons over and then continue the extraction until about ten more portions have been returned to flask. After the extraction is completed, disconnect the apparatus and dry thimble in steam oven to constant weight. Distill off the acetone in flask, dry in oven, and weigh. Residue in Thimble. — If a pure chicle has been used, this will be a light reddish color and somewhat brittle. Should it, however, be a black, elastic body, substitution in all likelihood has been employed in the manu- facturing process. To make a proper comparison, it is advisable to extract some pure chicle gum and compare the residues obtained. Extract. — This may consist entirely of the resinous matter in chicle. It will also contain any wax or oil used in compounding the substitute or finished gum. Weigh off a 1-gram sa,mple of the acetone extract, transfer to a 300-mil Erlenmeyer flask and determine the saponification value. Good results may be obtained by using 5 mils of benzene to take the resins into solution and then adding 20 mils N/2 alcoholic KOH for the saponi- fication. Run a blank, using the same amounts of benzene and KOH. A funnel with the stem cut short is a very satisfactory reflux condenser. Replace any alcohol lost in the boiling, adding the same amount to both flasks. One hour's boiling is usually sufficient to complete the saponi- fication. Add 100 mils of cold water (recently boiled and cooled) 1 mil of phenol phthalein solution and titrate with N/10 HC1. Calculate the number of milligrams of KOH required to saponify 1 gram of resin. Most of the resins from the rubber gums likely to be used, will have a saponi- fication value of 87 to 100 milligrams of KOH. Waxes. — Use a 1-gram sample of the resinous extract. Warm with about 50 grams of glacial acetic acid. The resins, fatty matters, and mineral oils will go into solution, while the paraffin, on cooling, separates out almost quantitatively. Filter on a tared filter, wash three or four times with cold, glacial acetic acid and then follow with four or five washings with cold water, to remove the acid. Dry in steam oven and 1 The Chemist Analyst, Nov., 15, 1916, page 5. GUMS AND RESINS 515 weigh. Use a stoppered weighing bottle in drying the filter and make the drying and final weighing in the same bottle, to prevent loss of wax, which in drying may melt and pass through the filter. PLASTERS Plasters consist of a medicament incorporated in a base of some resin- ous character and spread upon cloth or paper. Plaster mass or the base on which the adhesive character depends, varies in composition. Among the combinations may be mentioned the following : Rubber, Burgundy pitcn and olibanum. Lead oleate or lead plaster as it is commonly called. Soap, lead plaster, and colophony. Lead plaster, yellow wax, colophony, ammoniacum, myrrh. Bdellium, olibanum, turpentine, and storax. Individual plasters or those to which specific names are applied include : Ammoniac plaster composed of ammoniacum and acetic acid Aromatic plaster composed of lead plaster with cloves, cinnamon, ginger, capsicum, camphor, and cotton seed oil. Camphorated Brown Plaster (Camphorated Mother Plaster) com- posed of lead oxide, olive oil, yellow wax, and camphor. Galbanum plaster, composed of galbanum, turpentine, Burgundy pitch, and lead plaster. Pitch plaster, composed of Burgundy pitch, olibanum, colophony, bees- wax, and olive oil. Canada pitch plaster, composed of Canada balsam and yellow wax. Resin plaster, composed of colophony, lead plaster, and yellow wax. Lead Plaster (diachylon) prepared with lead oxide and olive oil which yields practically lead oleate. The plaster masses described above or the named types of plasters are employed in making up the various medicated plasters. The following list includes the principal forms of medicated plasters which will be en- countered in analytical work: Aconite with base of resin plaster. Ammoniacum with mercury and oleate of mercury in a lead plaster base. Arnica in resin plaster. Asafetida in a base of lead plaster, galbanum, and yellow wax. Belladonna in resin or soap plaster. Capsicum in resin plaster. Compound tar plaster composed of colophony, tar, Podophyllum resin, Phytolacca, and Sanguinaria. 516 GLUCOSIDES, GLUCOSIDAL DRUGS AND NATURAL DRUGS Iron or Strengthening plaster composed of ferric hydroxide in Bur- gundy pitch and lead plaster. Mercurial plaster, composed of mercury and mercury oleate in lead plaster. Menthol in resin and beeswax. Antimonial composed of tartar emetic in Burgundy pitch. Opium in Burgundy pitch and lead plaster. Cantharides, composed of cerate of cantharides and Burgundy pitch or powered cantharides in beeswax and soap plaster. Lead iodide in lead plaster and resin. Zinc plaster consists of zinc oleate and palmitate. Mustard plaster consists of powdered black mustard deprived of its oil incorporated in a rubber base. Adhesive plaster consists of rubber, resins, and waxes with a filler of absorbent powder such as orris root or starch. Court plaster consists of a mixture of isinglass, glycerin, and benzoin. Analysis of Plasters. — The analysis of a plaster of alleged composition for the purpose of identifying its medicinal constituents is neither difficult nor complicated. A detailed scheme which is both simple and accurate has been described in my work " The Qualitative Analysis of Medicinal Preparations." After separating the medicinal components from the plaster base the character of the latter usually reveals itself more or less accurately by conducting the routine resin analysis. The values obtained can then be compared with the data recorded in the preceding pages. Part IV ORGANIC SUBSTANCES OTHER THAN ALKALOIDS AND GLUCOSIDES CHAPTER XV HYDROCARBONS— ALCOHOLS— ETHERS A Classification of a group of substances under the term "synthetic" without reference to their chemical relationship is not feasible, and the limitations of the term " synthetic " are not easy to define. Certain sub- stances are undoubtedly " synthetic " in all respects and, might easily be considered under such a heading; thus we have acetanilid, acetphene- tidin, sulphomethan and saccharin, which, while they belong to definite groups of substances constitutionally, might be treated under one group from the standpoint of the analyst of medicinal products. On the other hand we have acetyl morphin, diacetylmorphin, eucain, anesthesin, euquinin, and homatropin, which are all products of the laboratory and yet are best treated under other headings, the morphin derivatives con- jointly with the opium basis, the anesthetics with cocain, quinin deriv- ations with quinin, and homatropin with its parent substance atropin. Again we meet with iodoform, dithymoldiiodide, bismuthbetanaphtho- late and mercurol, which fall more naturally under the general consider- ation of iodine, bismuth, and mercury derivatives. It was therefore decided at the outset to arrange the material as nearly as possible accord- ing to its chemical relation, though deviations from this procedure must necessarily occur. There have been a vast number of " new remedies " or " synthetics " evolved during the last two decades, but fortunately for the drug analyst the substances which are used in mixture are comparatively few and in most cases their separation and detection is not difficult. By far the greater number of these substances are dispensed by themselves either in their pure condition in prescriptions, or in pills, tablets, and capsules, 517 518 ORGANIC SUBSTANCES with some simple diluent or excipient. Their melting-points and general properties have been carefully determined, and after a few tests to determine their character, they may be assigned to their proper class and identified in this connection. The writer wishes to call especial attention to Professor Mullikin's work, "The Identification of Organic Substances," which will furnish valuable aid in pointing to the identity of an individual. The substances of this group which have an extended use in medicine include acetanilid, acetphenetidin, antipyrin, chloroform, sulphomethane, sulphonethylmethane, phenolphthalein, saccharin, hexamethylenamin, chloral, acetyl salicylic acid, oxyquinolin, methylene blue, guaiacol car- bonate, salol, salophen, resorcinol, and perhaps a few others. In the general scheme of drug analysis which is outlined in my work "Qualitative Analysis of Medicinal Preparations," the fractions in which these products will be found are indicated, and in the accompanying work there is given a detailed description of their properties and tests and an arrangement of the substances as nearly as feasible according to their chemical constitution. Many of the substances described in this section are not themselves drugs, or medicinal agents, but as they may result from decomposition of other products which are drugs, and as their identification or determi- nation may be important factors in the particular research under consider- ation, it is important that they should be discussed, and sufficient data assembled to aid the worker, without the necessity of consulting other works on organic chemistry. HYDROCARBONS The aliphatic hydrocarbons are of little moment to the drug chemist. The gaseous members of the methane, ethylene, and acetylene groups may be passed over unnoticed. The liquid and solid hydrocarbons of the methane group occur in petrolatum and paraffin The saturated hydrocarbons of the aliphatic series are markedly indif- ferent substances. They are unaffected by acids or alkalies, are permanent in the air and sunlight, insoluble in water and but sparingly so in alcohol, though they go into solution with ease in ether and chloroform. Deriva- tions of place of some of the lower members are used medicinally, but none of them can be prepared directly from the hydrocarbons themselves. The hydrocarbons of the methane series have an important place in medicinal chemistry in the form of petrolatum or vaseline and in liquid petrolatum, white neutral oil, and albolene. Petrolatum or vaseline varies in color from white to dark red, but the pharmacopoeial product cannot be darker than light amber. It is a soft, HYDROCARBONS— ALCOHOLS— ETHERS 519 unctuous mass, practically odorless and tasteless, but giving a faint petroleum-like odor on heating. It may be slightly fluorescent and is transparent in thin layers. Petrolatum melts 45°-50°, and is lighter than water. When heated to 60° its specific gravity is .820-850. It is insoluble in water, but will emulsify with it if the mixture is stirred sufficiently. It is but slightly soluble in 95 per cent alcohol, but dissolves in boiling absolute alcohol and in ether, chloroform, petroleum ether, benzol, carbon disulphide, oil of turpentine, fixed and volatile oils. Petrolatum is unsaponifiable and has no iodin value if pure. It resists the action of 85 per cent sulphuric acid, and is in general a very indifferent substance. Liquid petrolatum may be water white to slightly yellowish with a bluish fluorescence. Its specific gravity is from .870-.940 at 25° C. and in all other respects its properties are the same as those of the solid form. Petrolatum is the base of a great variety of ointments, cold creams, and petroleum emulsions. The liquid form has acquired considerable reputation in bowel troubles. Paraffin which is a mixture of hydrocarbons of still higher melting- points, is a white, translucent substance of wax-like consistency. It is used to a large extent in ointments, pastes, and creams, acting as an agent to give the product its proper consistency. Mixtures of petrolatum and ammonium oleate are marketed under proprietary names and are combined with iodin, sulphur, ichthyol, etc. The determination of hydrocarbons in pharmaceutical mixtures and toilet preparations resolves itself practically into a measure of the unsa- ponifiable matter. The most satisfactory procedure for accomplishing this is one which was worked out in my laboratory by T. M. Rector, and the details follow : Weigh from 5 to 10 grams of the oil or fat into a 300-mil Erlenmeyer flask, add 100 mils of alcoholic potash (40 grams per liter) and heat on the water-bath until saponification is complete. A small funnel in the neck of the flask will serve as a reflux condenser. After saponification, which usually takes from thirty to forty-five minutes, the hot soap solu- tion is poured into a 16-oz. Squibb separator and the flask rinsed with two 25-mil portions of 95 per cent alcohol, making a total of 150 mils of 95 per cent alcohol. The separator is cooled to room temperature by shaking under the tap and 75 mils of light petroleum ether added. The petroleum ether dissolves in the alcohol, forming a clear solution. About 125 mils of water are next added and the mixture shaken. At this point the petroleum ether will separate and rise to the surface of the alcohol-water mixture in a clear layer. The soap solution is drawn off into a second separator and extracted twice with 50-mil portions of petro- 520 ORGANIC SUBSTANCES leum ether. The combined petroleum ether extracts are filtered into a tared beaker and evaporated on the water-bath. The residue is dried in a vacuum desiccator and weighed. To make a successful determination, the following points are essential: 1. Use a petroleum ether completely volatile under 80°. 2. The alcohol content of the soap solution after dilution with water should be very close to 55 per cent by volume. It is necessary to know the volume of the alcoholic potash solution as well as the amount of alco- hol used in rinsing the flask. A lower content of alcohol than 50 per cent will result in emulsions, while a higher percentage than 60 will cause the retention of a large part of the petroleum ether in solution. 3. A beaker should be used for the final evaporation. The unsaponi- fiable matter will " creep " over the edges of an evaporating dish and cause low results. 4. The residue should be placed in a vacuum desiccator immediately after the petroleum ether has evaporated, to avoid loss by volatilization. This method will of course give all of the unsaponifiable matter, includ- ing alcohols from waxes. These may be separated by boiling with acetic anhydride under a reflux and repeating the shaking-out process. Some of the essential oils, notably oils of rose and chamomile, contain hydrocarbons in sufficient quantity to cause a solidification of the whole or a part of the sample. They are called stearoptenes, and are evidently mixtures of paraffins or defines, the identity of which has not yet been ascertained. The stearoptene from rose oil melts 35°, and when distilled in vacuo separates into two fractions, melting 22° and 40-41° respectively. Other essential oils in which hydrocarbons are known to occur include Arnica flower, dill, caraway herb, neroli, sassafras leaf, gaultheria, betula, and wild bergamot. Benzol, C 6 H 6 Benzol, benzene, phenyl-hydride or coal-tar naphtha is a colorless, mobile, highly refractive liquid, with a characteristic odor, specific gravity .883-885 at 15°, boiling 80-81°, soluble in alcohol, ether, chloroform, glacial acetic acid, acetone and oils and insoluble in water. Below +6° C. it is a crystalline solid. Concentrated nitric acid at ordinary temperature converts benzol into nitrobenzol, C6H5NO2, a substance with a character- istic odor, boiling 205°, known as " Oil of Myrbane," Sulphuric acid converts benzol into benzene-sulphuric acid, C6H5SO3H. Chlorin and bromin act on benzol at moderately high temperatures or in presence of direct sunlight to form hexa addition compounds, CeHeXe. At ordinary temperature or in the absence of sunlight substitution products are formed, HYDROCARBONS— ALCOHOLS— ETHERS 521 In medicine benzene is used as an antispasmodic in whooping cough and influenza. It is dispensed in capsule form, as an emulsion, and mixed with sugar. Cymene. Methylisopropyl Benzene, C^H^iCHs) (C3H7) Cymene is capable of existing in three modifications, but the para form is the only one of interest to the drug chemist. It occurs in oil of thyme, and has been reported in the analysis of oils of Monarda punctata, Cuminum cyminum, Cicuta virosa and Origanum. Para-cymene is a colorless liquid boiling 175-176° C, inactive to polarized light, with an agreeable odor resembling- oil of lemons. Its specific gravity is .86 at 15°. Chromic acid or dilute nitric acid eventually convert it to terephthalic acid, which serves as a means for its identi- fication. To carry out this reaction it is boiled under a reflux for thirty hours with excess of strong chromic acid mixture, or until the mixture dropping from the condenser is no longer oily. After cooling and dilut- ing with water, the insoluble terephthalic acid is filtered off and purified by solution in ammonia, boiling with animal charcoal and reprecipitation by hydrochloric acid. The purified acid sublimes without melting. Cymene may be identified by converting it to oxyisopropyl benzoic acid. It is treated with potassium permanganate in the proportion of 1-6 in a 4 per cent aqueous solution and boiled under a reflux. When the oxidation is complete, it is filtered, the filtrate evaporated, the potassium salt extracted with alcohol, the solvent evaporated, and an aqueous solution precipitated with dilute sulphuric acid, the filtered acid being recrystaUized from alcohol. Melting-point, 155-156°. Cinnamene or Styrene, (C 6 H 5 CH = CH 2 ) Styrene is an unsaturated hydrocarbon having the composition of a phenylethylene. It occurs in liquid storax and is a colorless, highly refractive liquid, boiling 144-145° C, with a pleasant odor. It poly- merizes readily to meta-styrene. THE CYCLIC HYDROCARBONS The cyclic hydrocarbons are of considerable interest to us owing to their prevalence in essential oils, many of which are used to a greater or less extent in drug products, and whose identity may sometimes be a question of importance. These hydrocarbons may be considered as polymers of pentine, CsBfe, and have been arranged by Wallach in the following classes : 522 ORGANIC SUBSTANCES A. Pentines or hemiterpenes, CsHg, as isoprene and valerylene. B. Dipentines or terpenes, (CsHg^ or Ci Hi 6 , including pinene ; limonene, fenchene, camphene, phellandrene, etc. C. Tripentines or sesquiterpenes, C15H24, as cedrene and cubebene. D. Diterpenes, C20H32, as colophene and copaivine. E. Polyterpenes, (CsHs)**, as the polyprene of caoutchouc. Those of the B and C classes are of importance in this work. The chemistry of the diterpenes and polyterpenes is still in need of much extended research. The terpenes are isomerides of the moleculer formula C10H16. They may nearly all be derived from a hydrocarbon terpane or menthane, C10H20, which has the composition of a methyl isopropyl cyclohexane. •CH2 CIl2\ /CH3 . CH3— CH< >CH— CH< X CH 2 — CH 2 / X CH3 which is closely related to cymene and from which it may be derived by reducing the aromatic nucleus. It is convertible to cymene by oxidation. The terpenes, C10H16, which are the intermediate between cymene, C10H14, and terpane, C10H20, differ from the latter by four atoms of hydro- gen in the molecule. They divide themselves into two groups contain- ing in addition to the hexamethylene ring. I. Two double bonds as in the monocyclic terpenes. II. A double bond and a second ring system, as in the dicylic terpenes. The structure of the monocylic terpenes is fairly well established. />CH — CH2 \ /CH3 Limonene and Dipentene CH3 — C\ yCR — C/ X CH 2 — CHC=C< X CH 2 — CH 2 / X GH3 /CH2 — CH2\ /CH3 Beta-phellandrene CH 2 =C< >C— CH/ CH^CH / X CH 3 // CH — CH ^ /CH3 1 Terpinene CH 3 Cf >C— CH < X CH 2 — CH 2 / X CHs x/CH — CH2K /CH3 1 Alpha-phellandrene CHsCf >CH— CH< XJH= CH / XJHa 1 In these two both double bonds are in the nucleus, and they may be described as dihydro-p-cymenes. HYDROCARBONS— ALCOHOLS— ETHERS /CH 3 523 C Sylvestrene CH3— C // CH— CH ^CHs-CHs/ \ CH S CH 2 The structural formulas of the' dicyclic terpenes is less clearly estab- lished. Pinene is probably CH 3 and its hydrochloride is CH 5 CH- I CH 3 — C- I CH 2 C- — CH 2 CH 3 -CHC1 Bornylene is probably CH3 CH 2 — CH- I CH 3 — O I CH 2 - -CH -CH 3 — CH -C- I CH3 The monocyhc terpenes are characterized by generally forming tetra- bromides, while the dicyclic terpenes usually form only dibromides, though they often add on 2HBr owing to the rupture of the ring systems by the acids. With the exception of camphene, which is a solid, the terpenes are light, colorless, volatile, odorous liquids. They resemble each other closely in their physical properties, and are difficult to identify by resorting to these characteristics, and this is further complicated by the ease with which one terpene will change into another or from one modification to another. By resorting to chemical means, better results will be obtained, and 1 A meta-compound analogous to Limonene or Dipentene. 524 ORGANIC SUBSTANCES the formation of one or more of the following compounds will often serve to identify the terpene under investigation. The bromides may be formed by dissolving 1 volume of the terpene in 4 volumes of alcohol and 4 of ether. The solution is well cooled by ice and .7 volume of bromin is slowly added. The Crystalline precipitate is washed with cold alcohol and recrystallized from ether. The nitrosochlorides may be prepared by dissolving the terpene in about 2\ times its volume of glacial acetic acid, cooling in a mixture of ice and salt and adding the same quantity of ethyl or amyl nitrite. This mixture, after thorough cooling, is slowly treated with half its volume of a mixture of equal volumes of glacial acetic and concentrated hydro- chloric acids, allowing time for the blue color to disappear before adding more acid. After fifteen minutes the crystals are filtered, washed with alcohol, dried at room temperature, dissolved in the least possible quantity of chloroform, from which solvent the nitrosochloride is reprecipitated by adding methyl alcohol. After drying its melting-point and micro- scopic appearance may be determined. The nitrosobromides may be formed in the same way. On treating the terpene nitrosochlorides with alcoholic potash or cautiously heating them alone, the elements of hydrochloric acid are removed and products of the composition C10H15NO obtained. The mono-hydrochlorides are formed by passing a stream of dry hydro- gen chloride through the dry terpene. The dihydrochlorides are produced by the action of moist hydrogen chloride. They are conveniently prepared by mixing a solution of the terpene in glacial acetic acid with glacial acetic acid saturated with hydro- gen chloride. The dihydrochloride may be crystallized out of a mixture of alcohol and ether. The dihydrobromides may be prepared in the same way. The tetrabromides are prepared by dissolving the terpene in glacial acetic acid and adding bromide. The tetrabromide is recrystallized from ethyl acetate. Sesquiterpenes, C15H24 The sesquiterpenes are viscous substances with higher specific gravity and boiling-points than the terpenes. When treated with bromin or iodine and the product distilled with water, cymene is produced. Many sesquiterpenes have been described, but the individuality of all but a few is questionable. Caryophyllene is well established as the sesquiterpene of oil of cloves and it also occurs in copaiba. The sesquiterpenes are characterized by the formation of dihydro- chlorides and tetrabromides; nitrosochlorides (NOC1), nitrosates (N2O4) and nitrosites (N2O3). HYDROCARBONS— ALCOHOLS— ETHERS 525 oj a to C ,5 Xi P-. Fennel oils, Eu- calyptus, am- agdalina, Pi- nus montana, Star -anise, other oils o O 03 X IC IO 00 o CO 5 o C o c w 6 a oj a *a OJ H o3 - 3 OJ o o a o O N X o O CN co X o O oo 3 .2* o 6 6 a _0J "o s 'a M CO H a i o| Is 2 o a Sy_ OJ o o a OQ o X o o o oj s OJ 1 02 •53 * 3-2 §tcH'o Ph o CM 03 00 o CO CO CO + o CM "3 o CO rs o CO 3 go OJ S l§ a a OJ.-* aT "3 a oj" N • K 3 " f* 3 v rt %a 3 o a.S a o o a (N "3 00 o o CM "3 X '3 3 1 o CO J. CO a Z2» a 13 mmw Z o o N "3 co 00 o o oo +7 o O CN 03 o -o '1 O o — C o a o 17° w 6 oj s o a ° 3 fl 5 °j 3 °fc o-o _ ■rt o --h OS £ © a ej o"aJ « o a co X o c 3 N ~~. O C5 o o o o 12 '3 13 3 75 "3 OJ s > o ■— a §£" S ,g a-a. . • a >>.:5 O N oa a CO X oo' IC X -H o N 03 «o CO o CO OJ Bo tn • o : O iC o S Oo Z?2 2S li 3 -d a >. ■> S3 6 B ea 'o OJ a 3 "3 «? CC 'o OJ a 02 - — a pc f "c c t 'c - 1 1 3 ^o "o o >> xs o a o t. ~Z 2 > P i s — i c 1 c .5 s - E- CD ^O O _£" 2 > 'Z a. - E 2 -t- a ■j z 2 — "a C (■ 2 526 ORGANIC SUBSTANCES m Oh B D c © '2 c S3 O c d a O a a) B lO 03 l> OS X O X 1 OS CI 00 N ©' a 0> u © '3 a S a O "oi 00 CO 1 C3 CO 1 OS re OS O t- c © '-P.3 03 a 2 C >. §03 BO X OS CS ec co 1 CO 5 O CO CO CM CO CM © c ^0 ">> -c a >> !- 03 O 08 'oi o3 6 l EC )Z £o3 oO O 03 X OS OS 1 os O O CM X OC O TOO 3> 5 a "3 ft 0Q "03 Q '3 a 32 5 « a "3 Ph C '5 a M O pq 01 2 c -5 >. = © 2 >) « 's 3 © £ c 03 © © § O OQ c <- 2 > ~z m 3 u % © IB -^ s "a z - ■*■ 2 HYDROCARBONS— ALCOHOLS— ETHERS 527 Terebene Terebene is a pharmacopoeial product consisting of dipentene and other hydrocarbons, obtained by the action of sulphuric acid on oil of turpentine and subsequent rectification with steam. It is a colorless limpid liquid, boiling 160-170° C, having an agreeable thyme-like odor. Its specific gravity is .860-.865 at 25° C, and it is only slightly soluble in water, but dissolves readily in alcohol, ether, carbonbisulphide, and glacial acetic acid. It is inactive to polarized light and thereby differs markedly from oil of turpentine. On exposure to fight and air it becomes resinified and acquires an acid reaction. It is used in a variety of ailments, including chronic bronchitis, flat- ulency, uterine cancer, genito-urinary diseases, and tubercular troubles. Naphthalene, Ci H 8 Naphthalene or tar camphor is a white scaly or crystalline substance, with a characteristic coal-tar odor, melting 79-80°, boiling 218°, insoluble in water, but to which it imparts its odor and taste on boiling, soluble in alcohol, ether, chloroform, fixed and volatile oils. Its vapor is inflam- mable, burning with a luminous, smoky flame, and it is volatile slowly at the ordinary temperature. It yields a nitro-derivative and a sulphonic acid in a similar manner to benzol, and on boiling with dilute nitric or chromic acid is slowly oxidized, yielding carbon dioxide and orthophthalic acid. When dis- solved in alcohol and treated with an alcoholic solution of picric acid, yellow crystalline naphthalene picrate, CnH6-C6H2(N02)30H, melting 149°, is formed. Naphthalene possesses a number of therapeutic properties, but it has a limited use as a medicament. It has been employed in intestinal catarrh and inflammation, tapeworm, cholera, typhoid, and chronic bronchitis. Externally it may be encountered in ointments for skin diseases. Anthracene, Ci 4 Hi Anthracene, with structural formula 528 ORGANIC SUBSTANCES crystallizes in colorless, lustrous plates, with blue fluorescence, melting 213°, boiling 360°. It is freely soluble in hot benzol, but only slightly in alcohol and ether. A saturated alcoholic solution mixed with an alcoholic solution of picric acid gives a precipitate of ruby-red needles of anthracene picrate, melting 138°. This compound may be resolved into its compo- nents when treated with considerable alcohol. Anthracene itself has no interest to the drug chemist, but it is the basic substance of an important series of principles which are the active medicinal agents of the laxative drugs Cascara sagrada, Senna, Rhubarb, Rhamnus fragula, and Aloes. These principles are hydroxyanthra- quinones. / co \ Anthraquinone, C6H4C }CqH4, is formed by oxidizing anthracene XJCK with chromic acid. It forms pale yellow needles, melting 277°, and sub- limes at higher temperature in long sulphur yellow needles. It is very stable and is attacked only with difficulty by oxidizing agents, sulphuric, or nitric acids. Anthraquinone forms sulphonic acids when heated with sulphuric anhydride. When a trace of anthraquinone is mixed with dilute sodium hydroxide, a little zinc dust added and the mixture boiled, an intense red color is produced, but on shaking in contanct with air the solution is decolorized. Oxanthranol is formed, which dissolves in alkali to a red solution, but in contact with air it is oxidized to anthraquinone, which separates as a white flocculent precipitate. Anthraquinone on treatment with powerful reducing agents is finally /C(OHV converted to anthranol, C^ECk /C6H4. X CH / .COIL .OH Dihydroxyanthranoloranthrarobin,C6H4\ J>CH2CeH2(OH)2. It is a dark-red substance, melting 282°, almost insoluble in water, moderately in alcohol and readily in alkaline liquids, forming reddish-violet solutions. When distilled with zinc dust it is reduced to anthracene and with acetic anhydride it forms a diacetate, melting 180°. HYDROCARBONS— ALCOHOLS— ETHERS 529 Alizarin yields insoluble lakes with metallic oxides, the ferric compound is violet black, the calcium blue, the tin and aluminum different shades of red. A piece of calico will be colored yellow by a solution of alizarin, but not fast. But if one previously mordanted with aluminum salt be used, a fast red will be formed on the cloth, or with iron a dark purple. The mordanting often requires two operations, first the cloth is soaked or boiled in an acetate or sulphate bath of the metal, then immersed in a weak alkali (ammonia, sodium carbonate, or lime) and then dipped in the alizarin solution. These facts will be of service to the analyst who is concerned with the testing of the oxyanthraquinone principles of the aforesaid drugs, Purpurin Purpurin is a-^a'-trihydroxyanthraquinone. Its isomeride, anthra- /C(X /OHa purpurin, C6H3(OH)<^ }CoH 2 C CH h/ / CH 2 CH 2 C /\ H OH Borneol crystallizes in laminae and plates, melting 203-204° boiling 212°. Its odor is similar to camphor and also resembles amber. Both modifications are alike in their chemical properties. On oxidation with chromic acid it yields camphor, and with nitric acid camphoric acid results. Phosphorus pentachloride converts it into bornyl chloride, and on boiling the latter with anilin, camphene is produced. It is very stable towards dehydrating agents such as zinc chloride and sulphuric acid, differing HYDROCARBONS— ALCOHOLS— ETHERS 555 thereby from the isomeric isoborneol. T t forms addition products with chloral and bromal, the former melting at 56° and the latter 105-109°. Borneol can be separated from camphor by heating with succinic acid anhydride. The sodium salt of the ester produced is soluble in water and therefore easily separated from camphor. The corresponding deriv- atives of phthalic acid may be used. Bornyval Bornyval is borneol isovalerate, CH 3 CH(CH3)CH2COO-CioHi 7j the isovaleric acid ester of borneol. Borneol isovalerate is a clear aromatic liquid, having an odor resembling oil of rosemary and at the same time a weak odor and taste of valerian. It is insoluble in water, but dissolves in all proportions of alcohol and ether. The liquid boils at 225° to 260° C. under ordinary pressure. At a pressure of 50 mm. it boils at 150° to 170° C, its specific gravity is .945 to .951 ; it is lsevorotatory, the angle of rotation lying between -30° and 32° in a 100-mm. tube at 20° C. It is said to be useful in the various neuroses. Gynoval Gynoval is isoborneol isovalerate, CH3CH(CH3)CH2COO-Ci Hi7, the isovaleric acid ester of isoborneol. It is a colorless neutral fluid of a peculiar aiomatic odor and mild oleaginous taste. It is difficultly soluble in water, but easily dissolved in alcohol, ether, acetone, chloroform, benzol, and petroleum-benzine. It boils at 132° to 138° C, under 12 mm. pressure, and has specific gravity of .952-.957 at 15 °C. Gynoval dissolves in concentrated sulphuric acid with formation of a red-brown color and liberation of an odor of sulphurous and valeric acids. On heating glynoval with an alcoholic solution of potassium hydrox- ide for several hours on a water-bath it is completely split up into its components, and on diluting this saponification liquid, isoborneol separates in solid form, while potassium valerate remains in solution. The action of gynoval is that of a mild nervine and antispasmodic, resembling that of valerian. Brovalol, CH 3 CH(CH 3 )CHBrCOO(C 1 oHi 7 ) Brovalol is bornyl brom-valerate, a colorless oily liquid having a slight aromatic odor, boiling at 163° under 10-mm. pressure, insoluble in water but soluble in alcohol, ether, and chloroform. It acts as a nervine. 556 ORGANIC SUBSTANCES Menthol, Ci H 19 OH Menthol is a saturated secondary alcohol, and the chief constituent of peppermint oils from Mentha arvensis and M. piperita. It is used to a large extent in medicinal preparations. It will be found in antiseptics, refrigerants, stimulants, and carminatives, and is almost always a constituent of the numberless gargles, mouth washes, and antiseptic liquids in daily household use. It will be found in tooth pastes, in ointments recommended for colds, sore throat, catarrh, head- ache, neuralgia, earache, toothache, piles, chapped hands, hay fever, insect bites, and in Hniments. Tablets and powders intended for antiseptics will be composed of men- thol with one or more sodium or potassium salts, borate, bicarbonate, chloride, sulphate, phosphate, benzoate, and salicylate with perhaps eucalyptol, thymol, and methyl salicylate. Mentholated throat tablets contain menthol, cocain, oil of anise, eucalyptol, and benzoic acid. The antiseptic liquids of the " listerine " type contain menthol, eucalyptol, methyl salicylate, thymol, boric acid and Baptisia tinctoria, Wild Indigo, and sometimes formaldehyde and its derivative; those of the " glyco- thymoline " type contain borates, bicarbonates, benzoates, glycerin, eucalyptol, thymol, menthol, Pinus pumilio, colored with cudbear, and in certain instances other ingredients. Liniments may contain a great variety of substances and with menthol there may occur one or several of the following: camphor, cantharides, capsicum, thujone, turpentine, sassasfras, rosemary, thyme or mustard oils, aconite, belladonna, opium, potassium iodide, iodin, mercury salts, ammonia, in a menstruum of alcohol, chloroform, acetone, alcoholic soap, some fixed oil, glycerin or acetic acid. Tooth powders may contain menthol, myrrh, cassia, oil, sassafras, eucalyptol, thymol, methyl salicylate, calcium carbonate and phosphate, magnesium carbonate or oxide, calcium peroxide, or magnesium, orris root, with and without soap. Practically the same constituents will be found in some combination or other in tooth pastes, to which in addition, glycerin and coloring matter are added. Ointments containing menthol vary in the character of the other materials, depending on the uses to which they are to be put. Ointments of menthol, camphor, and boric acid in a petroleum vehicle have a wide application; ointments with menthol, mustard oil, and aromatic balsams in lard constitute another class, and again we find a heterogeneous collec- tion embracing menthol, camphor, phenol, turpentine, quinin, and opium, in stearic acid recommended for croup, pneumonia, and similar ailments. There are many types of formulas, but it would be impossible to note all the combinations which are offered. Some of them are exploited with HYDROCARBONS— ALCOHOLS— ETHERS 557 special stress laid on some one ingredient, and some will consist of the ordinary antiseptics and refrigerants with an unusual substance added to give it the unique character assigned to it. It is sufficient to conclude by saying that menthol will be found in nearly all of them. Menthol crystallizes in colorless acicular or prismatic crystals, having a characteristic odor and a warm aromatic taste followed by a sensation of cold when air is drawn into the mouth. It melts 43° C, boils 212°, is only slightly soluble in water, but dissolves readily in all the organic solvents. When triturated with an equal weight of thymol, camphor, or chloral hydrate there results a liquid mixture. Menthol is kevogyrate, as it occurs in nature and the commercial article is always of this character. Its rotation is —49.30 in 20 per cent alcoholic solution or —57.7° in 10 per cent alcoholic solution. When oxidized with chromic acid a lsevo ketone, menthone, CioH 8 0, results. With permanganate the oxidation goes further with formation of keto- methylic and /3-methyladipinic acids, the latter melting 88-89°. On heating menthol with benzoic acid anhydride, menthyl benzoate is produced. This ester is difficultly volatile with steam and melts 54-55°. Menthol has such unique properties that no special directions are needed to identify it. Its odor is usually sufficient to determine its pres- ence. However, when it occurs in mixtures containing camphor it may easily be overlooked, because if the camphor is in excess (and it usually is), the odor of the menthol is completely overlooked. It is difficult to separate menthol from camphor. U. S. P. Method for Determination of Menthol in Oil of Peppermint. — Introduce 10 mils of the oil into a flask provided with a ground-glass tube- condenser (acetylization flask), add 10 mils of acetic anhydride and about 1 gram of powdered anhydrous sodium acetate, and boil the mixture gently during one hour. Allow it to cool, wash the acetylized oil with distilled water, and afterward with sodium carbonate T. S., diluted with an equal volume of distilled water, until the mixture is slightly alkaline to phenol- phthalein T. S., and then diy it with the aid of fused calcium chloride, and filter. Transfer 5 mils of the dry acetylized oil to a tared 100-mil flask, note the exact weight, add 50 mils of half -normal alcoholic potassium hydroxide V. S., connect the flask with a reflux condenser, and boil the mixture during one hour. After cooling, titrate the residual alkali with half-normal sulphuric acid V. S., using phenolphthalein T. S. as indicator, and calculate the percentage of menthol present by the following formula: Percentage of menthol = B -(AX 0.021) in which A is the result obtained by subtracting the number of mils of half -normal sulphuric acid V. S. required in the above titration from the 558 ORGANIC SUBSTANCES number of mils of half -normal alcoholic potassium hydroxide V. S. origi- nally taken, and B is the weight of acetylized oil taken. Coryfin Coryfin is menthyl ethylglycolate, CH 2 (0-C 2 H 5 ) -COCKCioHiq), the ethylgly colic acid ester of menthol. It is a limpid, colorless oil, having a very faint menthol odor, boiling under 20 mm. pressure at about 155° C, soluble in alcohol, ether, and chloroform; difficultly soluble in water. When heated with caustic alkalies it is split up into menthol and ethylgly colic acid. Coryfin is used as a substitute for menthol. Validol Validol is menthyl valerianate, CH3CH2CH2COOC10H19, with about 30 per cent of free menthol. It is a clear, colorless liquid, of the consistency of glycerin, having a mild pleasant odor, distinct from either that of menthol or valerian, and a refreshing cool and very faintly bitter taste, insoluble in water, but readily soluble in alcohol, ether, chloroform, and oils. It is decomposed by alkalies. On warming with sodium hydroxide solution, the odor of menthol manifests itself; if then the alkaline solution is acidulated with diluted sulphuric acid, the odor of valerianic acid is developed. Forman, or Chlormethyl Menthyl Ester, is described in full under formaldehyde. Estoral is the name given to so-called boric acid menthol ester, which is evidently a weak compound, for it is decomposed into its constituents by the action of water. It is used in chronic nasal catarrh. DIACID ALCOHOLS Terpine, CioHis(OH) 2 , exists in two forms cis-terpine and trans-terpine. The former majr be represented by the structure CH3 \ /CH2 — CH2\ /H >C< >C< OH / X CH 2 — CH 2 / x C(CH 3 ) 2 OH the latter OH v /CH 2 ^CH 2x /H CIV X CH 2 — CH 2 / \C(CH 3 ) 2 OH The former readily adds H 2 and becomes terpin hydrate, from which it may be prepared. Cineol or Eucalyptol may be regarded as the oxide corresponding to this form. HYDROCARBONS— ALCOHOLS— ETHERS 559 Cis-terpine melts at 104° and boils 258° C. Terpin hydrate is the product which is of special interest to the drug chemist. It is prepared by acting on turpentine, under proper conditions, with alcohol and nitric acid, or by the use of hydrogen peroxide, and is a colorless, lustrous crystalline body, CioHi 8 (OH)2+H20, with a slight aromatic odor and a somewhat bitter taste, melting 116-117° when rapidly heated. It loses its water of crystallization when heated for a prolonged period at 100°, and sublimes at the same temperature. Terpin hydrate is somewhat soluble in water, chloroform, and ether and dissolves with ease in hot water, alcohol, and glacial acetic acid. Cineol, doHi 8 Cineol or Eucalyptol may be prepared from terpin hydrate under suit- able conditions, but its interest to us lies in the fact that it is an important constituent of the oils of Eucalyptus. It is a colorless liquid with a characteristic camphoraceous odor, and a pungent cooling taste. It boils 176-177° C, and on exposure to a low temperature crystallizes into a mass of needles, melting -1° C. Its specific gravity is .930 at 15° or .921-.923 at 25°. It is optically inactive. It is soluble in all of the ordinary organic solvents, fixed and volatile oils, but does not dissolve in water, nor in solutions of the alkalies. Cineol is probably an oxide. It gives none of the characteristic reactions of the common classes of organic bodies. It does, however, give a number of characteristic reactions, some of which are valuable in its identification and estimation. When exposed to a freezing mixture and treated with an equal volume of syrupy phosphoric acid, it yields a phosphate which may be decomposed by hot water with regeneration of cineol. With bromin, cineol forms CioHi 8 OBr2, which crystallizes in red needles; this bromin compound decomposes with ease vielding water, bromin, and cineol. With a saturated solution of iodin in potassium iodide, cineol yields a mass which contains green lustrous deliquescent crystals. Cineol reacts with iodol to form a crystalline compound, melting 112°. It may be obtained by shaking the sample with the reagent until it is dissolved and then warming. As soon as the crystalline addition produced separates, it may be separated and recrystallized out of alcohol or benzol. When shaken with a fairly strong solution of resorcinol, cineol soon forms a white solid which falls to the bottom of the container. Dry hydrochloric acid gas conducted into a mixture of equal volume of cineol and petroleum ether gives a crystalline precipitate of an unstable hydrochloride. 560 ORGANIC SUBSTANCES When oxidized with a warm solution of potassium permanganate cineol gives dibasic cineolic acid, C10H16O5, melting 196-197°. The presence of cineol in medicinal products is usually apparent by the odor. If it is desired to separate it from a mixture such as a mouth wash or inhalant, the sample should be diluted with water and subjected to steam distillation, by which treatment the volatile constituents will be carried over into the receiver and separated from any salts, glycerin fixed oils, and other non-volatile substances. The distillate is cooled and shaken out with petroleum ether and the solvent separated, dried with calcium chloride, and then filtered and subjected to a stream of dry hydrobromic or hydrochloric acid which will threw out the cineol. After decanting and washing with petroleum ether, the crystals may be treated with water and the cineol freed. For the determination of cineol in the oils of Eucalyptus there are two types of procedures recommended, one depending on the absorption of cineol by phosphoric acid, and the other the combination of cineol and resorcinol. Each method has its own advocates. The method of the U. S. Pharmacopoeia is of the first type. Measure 10 mils of the oil, from a pipette, into a round-bottom glass dish of 50-mils capacity, which is imbedded in finely broken ice. Add 10 mils of arsenic acid T. S. and stir until precipitation is complete. When the mixture ceases to congeal further, allow it to stand for ten minutes in the ice bath. (If at this point a hard mass is formed, add 5 mils of purified petroleum benzin, and mix the mass well before proceeding with the assay.) Then transfer it immediately to a hardened filter paper, about 18.5 cm. in diameter, by means of a pliable horn spatula; spread it evenly over the surface of the paper and lay a second hardened filter paper over the top. Wrap several thicknesses of absorbent or filter paper around the hardened filters, and place the whole between the plates of a press and bring to bear all the pressure possible for about one minute. Change the outside absorbent papers and press again,. repeating the oper- ation, if necessary, until the eucalyptol arsenate is apparently dry, and separates readily when touched with a spatula. The pressing is not complete when a hard mass remains which is broken up with difficulty; and usually two changes of filter paper are required, pressing each time for about two minutes; if left too long in the press the compound may decompose. Now, transfer the compound completely by means of the horn spatula to a glass funnel inserted into a 100-mil cassia flask with a neck graduated to 10 mils into tenths. Wash the last portions of the precipitate into the flask with a stream of hot distilled water from a wash bottle, assisting the disintegration with a glass rod, place the flask in boiling water and rotate it until the compound is thoroughly broken up. Then add enough distilled water to cause the eucalyptol to rise into the HYDROCARBONS— ALCOHOLS— ETHERS 561 neck of the flask, cool it to room temperature and read its volume. This volume, multiplied by 10, shows the percentage of eucalyptol (cineol) in the oil. The following method, which depends upon the solubility of the resorcin -eucalyptol in excess of solution of resorcin, is stated to give results more accurate than the phosphoric acid method usually employed. Ten mils of the essence is introduced into a 100-mil Hirschsohn flask and well shaken up with about 80 mils of 50 per cent solution of resorcin for five minutes, the non-soluble portion of the oil is allowed to separate, then more resorcin solution is added to bring the non-cineol portion into the graduated portion of the neck, when its volume is read off. Oils which are very rich in cineol should first be diluted with an equal volume of essential oil of turpentine, or the cineol-resorcin compound will crystallize out, and in so doing retain some of the non-cineolic constituents. Obvi- ously in this case the volume of the liquid read off must be multiplied by 2 to give the percentage. Not only is the method more accurate and convenient, but by mere distillation or evaporation, the resorcin cineol compound is decomposed; the residual resorcin, evaporated to dryness, may be used again for another cineol determination. Eucalyptol enters into the composition of a number of popular remedies, including mouth washes and gargles and catarrh and hay fever remedies of the hyomei type. Its presence in most of these mixtures is apparent by the odor. It is also a component of tablets of the same general compo- sition as the gargles and douches, and is dispensed with sandal-wood oil and creosote in capsules. ETHERS Ethers are related to the metallic oxides in the same way as the alcohols are related to the metallic hydroxides. CH3OH corresponds to KOH and CH3OCH3 corresponds to KOK. The term " ether " is also applied to the esters of acetic and other acids, but these are, strictly speaking, ethereal salts, and will be considered in their proper place in a subsequent chapter. With the exception of methyl ether, which is a gas, they are mobile, volatile inflammable liquids, lighter than water and boiling at a lower temperature than the corresponding alcohols. They are even more inert than alcohols, as they are not acted upon by alkalies of alkali metals or by phosphorus pentachloride in the cold. They do not combine with dilute acids, but when heated they yield ethereal salts with the elimina- tion of water, and form substitution products with chlorine and bromin. 562 ORGANIC SUBSTANCES Ethyl or Sulphuric Ether, C2H5OC2H5 Ethyl ether is the only substance of this class which is of importance in our work, and as it is used almost entirely as an individual, and but seldom in mixtures, the question of its determination is not of great moment. For its identification its inertness and failure to give character- istic reactions for alcohols, aldehydes, and ketones in conjunction with its physical tests are sufficient. The analyst will often be called upon to determine the availability of a sample for anesthetic purposes, and in pharmaceutical establish- ments to pass upon its quality for manufacturing; and in special cases for a reagent in high-grade analytical work. The established grades of ether include: Anhydrous ether, which is practically pure ethyl oxide. Anesthetic ether, which complies with the requirements of the Pharma- copoeia which may contain alcohol up to 4 per cent and traces of acetal- dehyde, acids, and water. Commercial ether, which contains at least 95 per cent by weight of ethyl oxide. For some purposes one will encounter: Ether U. S. P. 1880, called " 80 ether," composed of about 74 per cent of ethyl oxide and 26 per cent alcohol containing a little water, specific gravity .750 at 15° C. Stronger ether U. S. P. 1880 containing 94 per cent ethyl oxide and about 6 per cent of alcohol containing a little water, specific gravity .716 at 25° C. Ether composes about one-third of Spirit of Ether and of Compound Spirit of Ether or Hoffmann's Anodyne. It is also present in some ethereal tinctures, lobelia, ferric chloride, valerian, belladonna, etc. Dr. Chas. Baskerville and Dr. W. A. Hamor l have made an exhaust- ive study of ether and devised a scheme for the examination of the product for analytical and anesthetic purposes with particular reference to the detection of avoidable impurities. The standards adopted by these gentlemen and the procedures to be employed for determining the necessary data are quoted herewith. 1. Specific Gravity. — Determine the specific gravity by means of a pyknometer at 15° C. 2. Boiling-point. — In the case of anesthetic ether, at least 97 per cent of the sample should distill over between 34° and 36° C. (at 760 mm.), and none of it should come over above 37°; after the fractionation to this temperature, no residue should remain in the fractionating vessel. 1 J. Ind. and Eng. Chem., 1911, 3, 301 and 378. HYDROCARBONS— ALCOHOLS— ETHERS 563 In the case of the anhydrous ether, at least 99.50 per cent should dis- till off between 34° and 36°, and none should come over above 36°. 3. Organic Impurities. — When 20 mils of the sample are added drop by drop to 20 mils of pure concentrated sulphuric acid, which is kept cooled during the tests and which is contained in a glass-stoppered bottle previously rinsed with concentrated sulphuric acid, the resulting solution should be colorless. The sulphuric acid should be gently shaken after the addition of each drop of ether in order to ensure perfect solution. 4. Odor. — When 50 mils of the sample are allowed to evaporate spon- taneously on filter paper, 10 cm. in diameter, contained in a flat porcelain dish, the paper should be odorless after the evaporation of the ether. The latter should be added to the paper in portions in such a manner as completely to moisten it. In the case of a decided odor being imparted to the filter paper, the ether should be rejected, but for further information may be tested for such impurities as " heavy oil of wine," fusel oil, etc. 5. Residue {Extractive Matter, Odor and Acidity). — (1) When 25 mils of the sample are allowed to evaporate spontaneously in a clean, dry glass dish, the moist residue must possess no odor, and must neither redden nor bleach blue litmus paper; this residue must evaporate completely on a water-bath — that is, there should be no fixed residue. (2) 100 mils of the ether under examination are allowed to spontane- ously evaporate in a flask until about 15 mils remain in the vessel. This residue should be free from color and foreign odor, and should comply in full with the following tests: (a) When 5 mils are allowed to evaporate at room temperature after the addition of 2 mils of water, the residue should neither redden nor bleach sensitive light-blue litmus paper. (6) When another portion of 5 mils is allowed to evaporate on a 9-cm. filter paper contained in a porcelain dish, there should be perceptible no foreign odor (amyl compounds, empyreumata, pungent matters, etc.) as the last portions disappear from the paper, and the latter should be left odorless, (c) On the addition of the remaining 5 mils to 5 mils concentrated sul- phuric acid, kept cool during the test and contained in a glass-stoppered tube previously rinsed with concentrated sulphuric acid, there should result no perceptible coloration. Anesthetic ether should comply in full with these tests. 6. Acidity. — (1) When 25 mils of the sample are allowed to evaporate at room temperature after the addition of 5 mils of pure water the residue should neither redden not bleach sensitive light blue litmus paper. (2) When 20 mils of pure ether are shaken with 10 mils of pure water and 2 drops of phenolphthalein, the same depth of color should result on adding an equal amount of N/100 potassium hydroxide solution as in a test using pure water alone. In the case of ether intended for special analytical purposes, the addition of .3-5 mil of N/100 potassium hydroxide 504 ORGANIC SUBSTANCES should produce an alkaline reaction. When more than 1 mil is required, the ether should be rejected for anesthetic purposes. 7. Water and Alcohol {Exclusion Tests for Pure and Anhydrous Ethers). (1) (This test is superfluous if the ether possesses a correct specific grav- ity.) A minute quantity of powdered fuchsin (rosaniline acetate), pre- viously dried at 100° C, is placed in a dry test-tube, 10 mils of the ether are added, and the tube is corked and shaken well. In the case of pure and anhydrous ethers, no amethystine color — even faint — should result. If the coloration imparted to the ether is considerable, the approximate percentage of impurity is determined by Allen's method. 1 (2) When several milligrams of anthraquinone and the same amount of sodium amalgam are added to 10 mils of the ether there should result no formation of red or green substances. The presence of both water and alcohol may be detected by this test. 8. Water {Exclusion Tests for Pure and Anhydrous Ethers). — (1) On shaking 1 gram of anhydrous copper sulphate with 20 mils of ether, the salt should not assume a green or blue color. (2) In important or doubtful cases, the test with amalgamated alum- inum may be used. If the ether contains no moisture and it responds to the tests under " Water and Alcohol " the presence of the latter may be really assumed, especially if the colors are marked. 9. Water and Aldehyde {Exclusion Test for Pure and Anhydrous Ethers). — When 15 mils of the sample are placed in a perfectly dry test- tube and a piece of metallic sodium about 5 mm. in diameter is added, there should result only a slight evolution of gas and the sodium should not possess, after standing six hours, a white or yellow coating and the ether should not be colored or turbid. Only when the ether has been previously treated with sodium will the latter retain a distinct metallic luster at the expiration of the test; otherwise the metal becomes coated with sodium hydroxide. In the presence of aldehyde the sodium hydrox- ide is more or less colored. 10. Acetaldehyde. — (1) Apply the fuchsin-sulphurous acid test of Francois. Pure ether should not restore the color to fuchsin decolorized by sulphurous acid. The red-violet color should be faint in the case of anhydrous ether. (2) On covering 5 grams of solid potassium hydroxide, in freshly broken pieces about 5 cm. in diameter, with 30 mils of the sample, and allowing the mixture to stand for six hours, tightly closed and protected from the light, and occasionally shaking, the potassium hydroxide should 1 All colorimetric tests should be performed preferably with a colorimeter, having tubes with an internal diameter of 1.5 cm. But other forms of vessels may be used; for example, a ground-glass-stoppered Erlenmeyer flask, of suitable size for the amounts of liquid prescribed in the test, has been found to answer. HYDROCARBONS— ALCQHOLS— ETHERS 565 not acquire a yellowish color, no yellowish or brown colored substance should separate, and the ether should not become turbid or assume any color. This is recommended as the exclusion test for anesthetic ether. Pure or anhydrous ether should give no response after standing twenty- four hours. (3) In the absence of alcohol, as indicated by these tests for water and alcohol, and confirmed by those given below, the following test may be applied for the detection of aldehyde: When 10 mils of the sample are agitated with 2 mils of Nessler's solution, a yellow color or black pre- cipitate is indicative of the presence of aldehyde. Pure ether is indif- ferent toward this reagent, but it is impossible to purchase ether which does not show a yellow color within fifteen minutes. For anhydrous or anesthetic ether, it is sufficient to require, therefore, that no black pre- cipitate settles out, although the mixture may assume an opalescent yellow color. 11. Alcohol. — The occurrence of alcohol may be ascertained as follows : (1) In the presence of water, a portion of the sample is dried over anhydrous potassium carbonate and then tested, in 10-mil portions, with (a) rosaniline acetate, and (6) anthraquinone sodium amalgam. (2) In the absence of other than mere traces of acetaldehyde, by Lieben's iodoform test. (3) In the presence of acetaldehyde, by this method: The amount of aldehyde in 25 mils is approximately determined colorimetrically by Francois method. A portion of 25 mils is then agitated with 25 mils pure water in a ground-glass-stoppered bottle, and the aqueous layer, which will show an increase in volume greater than 10 per cent of the ether taken depending on the amount of alcohol present, is removed and freed from dissolved ether by careful warming at 40° C, until ether is expelled. The alcohol in the water is then oxidized by potassium dichro- mate and sulphuric acid, the aldehyde produced is distilled off, and the amount contained in the distillate is determined approximately colori- metrically. By comparison with the percentage of aldehyde found as originally existing in the ether, the amount of alcohol may be calculated; however, the authors do not recommend the method as an exact quanti- tative one, but only as one for arriving at the approximate amount of alcohol contained in ether, and as a confirmatory test. 12. Peroxides (Exclusion Test for Ether of all Grades). — When 2 mils of a 10 per cent cadmium potassium iodide solution are well shaken with 10 mils of the sample, there should result no liberation of iodin within one hour. This may be easily determined by adding starch solution, although the yellow color which results in the presence of the merest traces of peroxides is easy to distinguish. The presence of peroxides 566 ORGAMIC SUBSTANCES may then be confirmed by any of the other tests devised by the authors, or by Jorissen's vanadic acid test. Ether prepared from alcohol denatured with methyl alcohol and pyridin bases often contains methyl ethyl ether and acetone. Frerichs l describes tests for detecting these bodies. For the detection of the first named a 250- or 500-mil sample, the boiling-point of which has been ascer- tained, is distilled and the boiling-point of the first 50 mils noted. If essentially lower than that of the sample the presence of the impurity is indicated, assuming of course that the absence of other usual impurities has been assured. As ordinarily determined the temperature of the boiling- point rises until it shows the boiling-point of pure ether. Frerichs shows an apparatus which can be operated so that the boiling-point may be observed for a long time. One hundred mils of the sample together with a glass capillary sealed at the top to avoid bumping are introduced and m 100 mils heat applied by insertion of base into an air-bath, the thermometer resting in neck (A) so that bulb reaches to X. Neck B is connected with a reflux. As soon as a steady and vigorous return from B is noted the thermometer will indicate a constant boiling-point. To detect acetone 100 mils of ether are shaken vigorously with 10 mils water. The ether is withdrawn and the aqueous liquid divided into two parts. To one 10 drops sodium nitroprusside solution are added, 6 drops sodium hydroxide, 5 mils water and then acetic acid in slight excess; if the liquid does not completely decolorize and a reddish or violet color appears acetone is indicated. The second portion is then tested with iodine and ammonia and heated until any black precipitate disappears and the liquid becomes clear and bright yellow. A crystalline precipitate of iodoform indicates acetone. Ether is one of the substances which has to be declared upon the label if it occurs in mixtures intended to be used as drugs. It is classed as a derivative of alcohol. The determination of ether in alcoholic mixtures 1 Apoth. Zeit., 28, 628. HYDROCARBONS— ALCOHOLS— ETHERS 567 has been described under Alcohol, page 539. With preparations which are more complex than the ordinary alcohol ether mixture, the alcohol and ether should be separated from the other substances by distillation, first diluting the sample with water. The distillation is best accomplished by heating 50-100 mils of the sample in a round-bottom flask, using a direct flame and running the distillate through a long and well-cooled condenser into a receiver surrounded with ice, the neck of which is well over the adapter, and stuffed with absorbent cotton. The distillate can then be transferred to the apparatus used for determining the ether. After the latter has been estimated the alcohol can be estimated in the aqueous portion by distillation. Determination of Small Amounts of Alcohol and Water in Ether. Mallinckrodt and Alt. 1 — The flask used was a 100-mil Regnault pykno- meter for taking the density of solids. It is best to have two and make the analysis in duplicate. Fifteen grams of potassium carbonate dried at 200 to 250° are placed in the bulb A and accurately weighed after replacing the stem B. Remove the stem and introduce quickly 50 mils of the ether for analysis. Replace stem and allow the flask to stand fourteen hours with frequent shaking. By removing the stopper and holding the inverted flask in the warm hand, the ether can be filtered out through the cotton plug X. Care must be used to insure a clear filtrate, otherwise there will be a loss of potassium carbonate. Examine the filtrate after standing to see that no finely divided carbonate has separated out. Fill the upper enlargement B with absolute ether and cause it to be drawn in by pouring some of the ether over the bulb. Shake well and expel the ether as before. Wash four times in this manner, which removes the alcohol from the salt. Now dry the flask, with cap C removed, at 50° until the carbonate can be shaken down into the flask. Remove the stem and replace it with a drying tube filled with carbonate of potassium to prevent access of external moisture and d y for 1 hour at 50°. Remove the drying tube and after sweeping out the remaining ether vapor with gentle suction for fifteen seconds, replace the stem and cool in a desiccator and weigh. Since it does not require much ether vapor to affect the weight, care is required to secure its complete removal without introducing moisture from an excess of air. A second weighing should be made after drying again for half an hour. The weights should be constant within about 4 mg. The difference between the weights of the potassium carbonate before and after treatment with ether is the weight of water in the sample taken. For the alcohol analysis, treat 100 grams of the sample with 40 grams of freshly dried potassium carbonate for fourteen hours in a glass-stopped flask, shaking frequently. The pyknometer is filled with the clear ether 1 J. Ind. and Eng. Chem., 1916, 8, 811. 568 ORGANIC SUBSTANCES and the specific gravity is determined at exactly 25° on the hydrogen scale. The per cent of alcohol may then be read off from the curve. Obviously if this curve is to be used, the gravity must be made in a bath at exactly 25° on the international hydrogen scale or else a new curve made by the operator at the temperature of his thermostat, which is a simple matter. 1 .7150 FIG. 1. .7140 SPECIFIC GRAVi: riES OF ETHER-ALCOHOL ^MIXTURES AT 25° C. HYDROGEN SCALE •£.7130 O.7120 O.7110 w .7100 .7090 1 1 2 3 Alcohol per cent by weight ORGANIC PEROXIDES These substances are related to the metallic peroxides in the same way that ethers are related to the oxides, and alcohols to the hydroxides. They may be considered as hydrogen peroxide in which the hydrogen atoms have been replaced by organic radicles. R— O R— 6 There are only two of these substances at present which have attained any commercial importance and which may be encountered in analytical practice, benzoylacetyl peroxide or acetozone and disuccinyl peroxide or alphozone. HYDROCARBONS— ALCOHOLS— ETHERS 569 These organic peroxides are used as intestinal antiseptics in typhoid and enteric fevers, and also for local infections where they can be brought in contact with the diseased surface such as ulcers, abscesses, inflammation of the mucous membranes, and infectious skin diseases. Acetozone is recommended as an antiseptic in ophthalmic, aural, and nasal practice, and is dispensed in an oil medium with chloretone. Benzoylacetyl peroxide, C 6 H 5 CO • O • O • OCCH 3 Acetyl-benzoyl peroxide occurs in white, shining crystals, melting at 36.6° C. When heated it slowly decomposes and volatilizes. Water at 25° C. dissolves one part in 1.560 or .639 gram in 1000 mils. It is soluble in oils to the extent of about 3 per cent, slightly soluble in alcohol, and fairly so in ether, chloroform, and carbon tetra-chloride, though all sol- vents slowly decompose it with the exception of neutral petroleum oils. In the presence of water it undergoes hydrolysis and slowly decomposes. As found in the market, acetozone is of a grayish-white color, possessing the properties of the crystalline substance, with the exception that the absorbent powder employed is insoluble. When dispensed at the bedside the powder is mixed with water and the solution consumed by the patient; but when sold by the druggist on prescription it is often put up in capsules. Succinic dioxide or Disuccinyl peroxide, (COOHCH2CH 2 CO) 2 02 It is a fluffy, white, crystalline powder, the crystals being small irregu- lar plates. It dissolves in 30 parts of water at ordinary temperature. It is moderately soluble in alcohol, acetone, and ethyl acetate, sparingly solu- ble in ether, insoluble in benzene, chloroform and petroleum ether. Odor- less or nearly so; softens at 115° C. and melts at 127° C. with decompo- sition. When brought into a flame it explodes, but it does not explode on percussion or friction. It deteriorates slightly on continued exposure to air, but if kept tightly stoppered and in a dark place it remains unchanged indefinitely. It is a powerful oxidizing agent, liberating iodin from potassium iodide. It can be identified by its physical properties and its powerful oxidizing action. To test its strength add 2 grams of potassium iodide to 1 gram of alphozone dissolved in 60 mils of distilled water. To this slowly add decinormal solution of sodium thiosulphate with constant agitation until the red-brown color of the iodin is just discharged. Each mil of sodium thiosulphate solution is equivalent to .0117 gram of alphozone; 1 gram of pure alphozone is equivalent to 85.41 mils decinormal sodium thio- sulphate solution. CHAPTER XVI ALDEHYDES AND KETONES ALDEHYDES This class of organic bodies includes the two very important medicinal agents, formaldehyde and chloral. The aldehydes are derived from the primary alcohols by the removal of two atoms of hydrogen from the — CH2OH group, thus methyl alcohol on mild oxidation gives formal- dehyde. They are named after the fatty acids which they yield on oxi- dation. With the exception of the gaseous body formaldehyde, whose physical properties are unknown, the lower members of the aldehyde series are colorless, mobile, neutral, volatile liquids, soluble in water, though the solublity decreases as the number of carbon atoms increases. The higher aldehydes are usually waxy solids, insoluble or nearly so in water but readily soluble in alcohol and ether. They are closely related to the ketones because they are similar in constitution, both classes containing the carbonyl group = CO. The lower members form crystalline addition compounds with sodium bisulphite, which are soluble in water, but insol- uble in alcohol and ether, and are decomposed on warming with acids or alkalies with regeneration of the aldehyde. They form oximes with hydro- hydroxylamine, and hydrazones or phenylhydrazones with phenylhydra- zine, a molecule of water being split off in the reaction. Both oximes and hydrazones are usually decomposed by hot concentrated hydro- chloric acid with regeneration of the aldehyde. Aldehydes on reduction with nascent hydrogen yield primary alcohols. With phosphorus pentachloride they give dihalogen derivatives of the paraffins, the oxygen of the =CO group being displaced by two atoms of chloride. Acet aldehyde gives dichlorethane, called ethylidene chloride, because it contains the ethylidene group, CH 3 • CH • CH3CHO +PCl 5 = CH3CHCl2+POCl 3 . Aldehydes combine directly with hydro- cyanic acid to form hydroxycyanides, \ /° H CO+HCN- >C< x X CN 570 ALDEHYDES AND KETONES 571 Aldehydes possess a number of characteristic properties which differ essentially from the ketones. On exposure to the air they are quite easily converted to fatty acids, they are readily oxidized by an ammoniacal solution of silver oxide, forming a silver mirror, and reduce Fehling's solution. They form addition products with ammonia > \ / 0H CO+NH3= >C< / X NH 2 which are usually crystalline, soluble in water, and yield the aldehyde again on treatment with dilute acids. They combine with two molecules of- alcohols to produce acetals, HOC2H5 \ /OC2H5 C=0+ = >C< +H 2 0. HOC2H5 / X OC 2 H 5 They are unstable in presence of alkalies, by which thay are converted to brown resins. Aldehydes undergo .polymerization which may take place spontaneously, but usually on the addition of some substance such as zinc chloride or sulphur dioxide. The common form of polymerization is the combination of three molecules of the aldehyde to form paralde- hydes such as paraformaldehyde or trioxymethylene and paracetalde- hyde often called simply paraldehyde. The constitution of these polymers are usually represented as follows : H2C CH2 I I o \ / c H 2 Paraformaldehyde They are decomposed into the original aldehydes on distillation with dilute mineral acids. They do not show the characteristic reactions of aldehydes and do not contain a ^>CO group. Formaldehyde is an excellent deodorant and disinfectant, but is too irritating for general medicinal use. As a disinfectant it has quite taken 572 ORGANIC SUBSTANCES the place of sulphur and it is almost universally used in embalming fluids. It is also valuable as an insecticide and a sweetened solution of commer- cial formaldehyde is a valuable agent for destroying the common housefly. In small amounts formaldehyde will sometimes be found in tooth pastes, washes, gargles, whooping cough inhalants, and eye lotions, and in fluid preparations recommended as deodorants. Paraformaldehyde or trioxymethylene is sold in tablet form as a remedy for hoarseness and sore throat and also for diarrhea, as it is somewhat astringent. It is dispensed in collodion in wart remedies and the vapors of the pure substance are recommended for consumptives and as an ingredient of surgical bandages and dressings. During the last decade a number of true and pseudo derivatives and compounds of formaldehyde have appeared on the market and will be discussed subsequently. Hexamethyleneamine is probably the most important derivative of formaldehyde medicinally, and is used as an antiseptic for the genito- urinary tract in all infectious diseases common to that locality, also as a urinary disinfectant in typhoid and for aborting coryza and acute con- ditions of the nasal passages. Formaldehyde, HCHO Formaldehyde or methaldehyde is known only in dilute solution and in the form of a gas at high temperatures. It would probably be a gas at ordinary temperature. The aqueous solution of formadehyde has a very penetrating, suffocating odor and a neutral reaction. It is a powerful reducing agent and readily undergoes oxidation, producing formic acid; and when treated with reducing agents it is converted to methyl alcohol. It reduces ammoniacal silver oxide, combines directly with sodium bisul- phite, and forms formaldoxime with hydroxylamine, which readily under- goes polymerization. When an aqueous solution of formaldehyde is evaporated paraformal- dehyde resu ts. The latter is a colorless amorphous substance, subliming readily and melting 171°. When strongly heated it is completely decom- posed into pure gaseous formaldehyde, but as the gas cools paraformal- dehyde again results. When heated with a large amount of water it is reconverted into formaldehyde. Formaldehyde forms several polymeric modifications. When its aque- ous solution is treated with lime water or other weak alkali formose results which is a mixture of substances belonging to the sugar group. The aqueous solution of formaldehyde containing not less than 37 per cent of the gas is recognized in the Pharmacopoeia. ALDEHYDES AND KETONES 573 Compositions for generating formaldehyde vapors consist of the solid substance or a solution mixed with permanganates or alkali peroxides or bisulphites. The general idea is that formaldehyde is held by the alkali or bisulphite and on the addition of permanganate in aqueous solu- tion the gas is liberated. In solid products the permanganate or per- oxide is included and simple addition of water liberates the formaldehyde. The oxidation of formaldehyde in soap solutions is prevented by the addition of sulphite. The identity tests given by formaldehyde are very striking, and are performed with an aqueous solution of the substance. The bright rose color given with sulphuric acid and resorcin has been described in detail under Methyl Alcohol page, 531. The morphin test may be carried out by adding a few drops of the suspected liquid to 5 mils sulphuric acid, cooling and pouring a little of the liquid on some morphin crystals on a white porcelain surface, when a deep purple color will be produced. Mullikin's beta-naphthol test is carried out by mixing a small quantity of the solution under examination with dilute alcohol 1-2 and adding about .005 gram beta-naphthol, 3 to 5 drops of hydrochloric acid and boil- ing. The precipitate is collected on a filter, washed with alcohol 1-2, and recrystallized out of boiling alcohol. The methylenedibetanaphthol formed melts 189°. A modification of the morphin test suggested by Bonnel directs that the surface of a dish or watch-glass should be moistened with sulphuric acid containing a trace of morphin and exposed to the vapors rising from the sample under investigation. If formaldehyde is present in the vapors the characteristic purple shade will be developed. The analyst will often be called upon to determine the strength of formaldehyde solutions for sale on the market. The hydrogen peroxide method is official in the Pharmacopoeia. Transfer 3 mils of Solution of Formaldehyde to a tared flask contain- ing 10 mils of distilled water, tightly stopper and weigh accurately. Add to the contents of the flask 50 mils of normal potassium hydroxide V. S., and follow this immediately but slowly through a small funnel with 50 mils of solution of hydrogen dioxide which has previously been rendered neutral to litmus with potassium hydroxide. Now heat the mixture cautiously on a water-bath for five minutes, shaking occasionally during this time; allow the mixture to cool, rinse the funnel and sides of the flask with distilled water and, after allowing it to stand thirty minutes, titrate with normal sulphuric acid V. S., using litmus T S. as indicator. It shows not less than 37 per cent of CH2O, correction being made for free acid if present. Each mil of normal potassium hydroxide V. S. corresponds to .03002 574 ORGANIC SUBSTANCES gram of CH2O. Each gram of solution of Formaldehyde corresponds to not less than 12.3 mils of normal potassium hydroxide V. S. The writer has found that very good results can be obtained by the iodine method. For this purpose an approximate N/5 Iodin is used, the exact titer of which need not be known because it is advisable to run a blank at the same time. The thiosulphate should of course be accurately standardized. Twenty mils of the solution accurately measured are introduced into a 500-mil graduated flask and made up to the mark with distilled water. Five mils of this solution, measured with a pipette, are placed in a glass-stoppered bottle, 30 mils N/1 sodium hydroxide added, and then with constant agitation the iodin solution is added from a burette, noting the amount, until the mixture appears bright yellow. After shak- ing for a minute 40 mils of N/1 sulphuric acid is added and the excess of iodin determined by titrating with N/10 thiosulphate. A blank is then run using the same quantities of alkali, iodin, and acid, the difference showing the amount of iodin consumed by the formaldehyde. One mil N/10 iodin is equivalent to .0015 gram formaldehyde. In calculating the percentage by weight the result must be divided by the specific gravity of the formaldehyde solution used. Formaldehyde can be determined in soap solutions by precipitating the fatty acids with sulphuric acid, filtering, and determining the formal- dehyde in the filtrate by the iodin method, the iodin being added before the alkali is introduced. After rendering alkaline the requisite N/1 sul- phuric acid is added and the excess of iodine determined by thiosulphate. Colorimetric Method. Collins and Hanzlik. 1 — Aliquot portions of the formaldehyde solution are measured into Nessler tubes, 2 mils of phloro- glucinol reagent (.1 gram of phloroglucinol dissolved in 10 mils of 10 per cent sodium hydroxide solution) is added to each, and the mixtures are diluted to 50 mils. After three minutes, the colorations obtained are com- pared with standard colors. The latter are prepared from definite quan- tities of Congo red solution (0.025 per cent in water containing 5 per cent of alcohol) and methyl orange solution (.01 per cent in water) ; 2.5 mils of the Congo red solution diluted to 50 mils gives the same coloration as 50 mils of .001 per cent formaldehyde solution when both are viewed in a column 12 cm. in depth. Different samples of Congo red do not always give the same depth of color, and the solution should be standardized against potas- sium bichromate; 2.5 mils of the .025 per cent Congo red solution diluted to 50 mils should have the same tint as a mixture of 1.7616 grams of potassium bichromate and 11.5537 grams of sulphuric acid diluted to 50 mils. The addition of methyl orange solution to the standards is necessary only when dealing with low concentrations of formaldehyde. The propor- tions of Congo red and methyl orange corresponding with different con- 1 J. Biol. Chem. 1916, 25, 231. ALDEHYDES AND KETONES 575 centrations of formaldehyde are given in the following table, the mix- tures being diluted to 50 mils and viewed in a 12-cm. column: Congo red Methyl Orange Congo red Methyl Orange Formaldehyde (0.025 per cent (0.01 per cent Formaldehyde (0.025 per cent (0.01 per cent solution) solution) solution) solution) Per Cent Mils Mil Per Cent Mils Mil 0.005 20.0 0.001 2.5 0.0033 11.0 0.0005 0.85 0.4 0.0025 9.0 0.0040 0.65 0.35 0.002 8.0 0.0002 0.23 0.18 0.0016 5.0 0.00014 0.20 0.15 0.00125 4.0 0.0001 0.13 0.10 To determine formaldehyde in urine, the phosphates present must be removed by treatment with sodium hydroxide solution and filtration before the above method is applied. Experiments with known quantities of formaldehyde showed that the method was more accurate than several other methods with which it was compared. The chlorimetric method may be used to determine hexamethylenetetramine in urine, etc., the latter is distilled without the addition of acid and the process applied to the distillate. If formaldehyde is also present in the urine, this must be determined previously and its quantity deducted from the total amount. Paraformaldehyde and Trioxymethylene The valuable properties of formaldehyde and the inconvenience of handling an aqueous solution soon created a demand for a solid form of the substance, and it is now marketed to a large extent in the polymerized condition. There is a confusion in some minds regarding the terms paraformal- dehyde and trioxymethylene, they are often used synonymously and with good reason, since their formation is so nearly identical, and for the infor- mation of the workers in this field who may be involved in legal quibbles concerning these points reference will be made here to the work of Auer- back and H. Barscall, 1 whose work on the polymers of formaldehyde may be summarized as follows : Paraformaldehyde is an amorphous colloidal substance with a molec- ular weight at least three times that of formaldehyde, and containing a variable quantity of absorbed water. When prepared by concentrating solutions of pure formaldehyde, it melts at about 150-160° C, dissolves 1 Arbb. Kais. Gesundt, Amt., 1907, 27, 183; Jour. Soc. Chem. Ind., 1907, 1294. 576 ORGANIC SUBSTANCES to the extent of 20 to 30 per cent in water at 18° C, is insoluble in ether and alcohol, is not altered by boiling with water, and forms an addition- compound with sodium sulphite. a-Polyoxymethylene, (CH 2 0)w, is obtained by the addition of 1 volume of concentrated sulphuric acid to 10 volumes of a pure aqueous solution of formaldehyde. It forms ill- defined crystals which melt at 163-168° C. when heated in a sealed tube, but are volatilized without melting when heated in an open tube. It is soluble to the extent of 11 per cent in water at 18-25° C, is insoluble in alcohol and ether, and forms a compound with sodium sulphite. Its vapors at 189° C. are composed of single CH 2 0-mols. /3-Polyoxymethy- lene is precipitated from a pure aqueous solution of formaldehyde by addition of .4 volume of concentrated sulphuric acid. It is crystalline, melts at 163-168° C. when heated in a sealed tube, is soluble to the extent of 3.3 per cent in water at 18° C, and up to 4 per cent in water at 25° C, and is insoluble in alcohol and ether. Its vapor density is 32 at 184° C. and increases slowly with rising temperature. It forms a compound with sodium sulphite, and when heated at 100° C. is converted into the 7-modification. 7-Polyoxymethylene — On addition of .4 volume of sul- phuric acid to formaline (a solution of formaldehyde containing methyl alcohol), 7-polyoxymethylene is precipitated along with the correspond- ing jS-compound, and is freed from the latter by treatment with sodium sulphite solution. It is distinctly crystalline and melts at 163-165° C. It dissolves in water at 18-25° C. to the extent of about .1 gram in 100 mils, and is insoluble in alcohol and ether. It does not react with sodium sulphite. At 184 and 198° C, its vapors contain polymerized molecules together with simple CEkO-mols.; the proportion of the former increases with rising pressure and decreases with rising temperature, the vapor densities at the temperatures given are 40 and 60 respectively. On boil- ing with water, 7-polyoxymethylene is converted into the 5-modification. 5-Polyoxymethylene, obtained by prolonged boiling of the 7-compound with water, forms ill-defined crystals, the melting-point (169-170° C. in a sealed tube) of which is lowered by even traces of impurities. This modification also melts when heated in an open tube, whereas all of the others are volatilized below the melting-point. It is insoluble in alcohol and ether and nearly so in water. Its vapor density slowly decreases between 190 and 240° C; at these temperatures the vapors consist of highly polymerized molecules which split up only very slowly into simpler ones. The compound does not ( react with sodium sulphite. a-Trioxy- methylene, C3H6O3, is formed by sublimimg polyoxymethylene and collecting the sublimate in water. Commercial " trioxymethylene " (/3+ 7-polyoxymethylene, or 7-polyoxymethylene) was sublimed by heat- ing in a glass retort in a slow current of nitrogen, and the sublimate was collected in a receiver containing a small quantity of water, and cooled ALDEHYDES AND KETONES 577 by ice. The distillate was submitted to fractional distillation, and the crystals which separated from the earlier fractions were purified by recrys- tallization from ether, or by sublimation in closed tubes. a-Trioxymethylene obtained in this way forms colorless needles or strongly refracting prisms, which are tough and soft, and melt at 63-64° when heated in closed tube. It boils at 114.5° C. at 759 mm., but is very volatile even at the ordinary temperature. It is soluble to the extent of 17.2 grams in 100 mils of water at 18° and 21.1 grams in 100 mils at 25° C; it is easily soluble in alcohol, ether, methyl alcohol, ace- tone, chloroform, carbon tetrachloride, carbon bisulphide, and benzene, and soluble with difficulty in petroleum ether. It is probably a cyclic compound, as unlike the other polyoxymethylenes, it does not respond to the usual reactions for aldehydes or ketones; with sodium sulphite it does not react either in alkaline or acid solution. It exhibits a constant vapor pressure and vapor density. Paraformaldelryde differs from a-polyoxymethylene chiefly by its amorphous condition and its content of adsorbed water, and by the proper- ties depending upon these factors. Paraformaldehyde and a, /3, y and 5 polyoxymethylenes all exhibit a tendency, decreasing in the order given, to split off formaldehyde as a gas or in aqueous solution; the aqueous solutions of these compounds do not differ from those of formaldehyde. Paraformaldehyde or trioxymethylene with formamide or acetamide gives compounds of the type R : NHCH2OH, used as antiseptics and uric acid solvents. E. Rust x has modified the hydrogen peroxide method in such a way as to render it available for the determination of formaldehyde in tablets and pastiles containing trioxymethylene. A funnel is placed in the mouth of a 250-mil conical flask, and 19-20 grams of the powdered substance weighed into it from a tube. The substance is washed down into the flask with 70 mils of N/1 sodium hydroxide delivered from a burette and dissolved. Then 9-10 grams of neutral 30 per cent hydrogen per- oxide are added at first in small portions and cautiously so as to avoid heating and filtering, and then more rapidly. After two hours the con- tents of the flask are heated cautiously to boiling and boiled to destroy the excess of peroxide. The funnel is now rinsed into the flask, a drop or two of phenolphthalein added and the liquid titrated with N/1 acid to very slight excess and then titrated back with N/1 alkali. Any required acidity or alkalinity of the substance must be tested for and if found titrated and allowed for. 1 Z. angew. Chem., 1906, 19, 138. 578 ORGANIC SUBSTANCES FORMALDEHYDE DERIVATIVES AND COMPOUNDS There have appeared on the market a number of compounds of for- maldehyde with various substances, among which may be mentioned condensation products with nucleinic acids, tannins, and tannin-like substances or their derivatives which claim antiseptic and astringent properties without the irritating effects of the formaldehyde, phenols, carbo-hydrates, starch, malt-extract, etc. Many of these are patented and sold with great claims for their therapeutic effects, and while some are true compounds, others are simply mixtures probably holding the formal- dehyde in absorption, or as the polymerized form from which the gas is regenerated under suitable conditions. These uncertain substances may furnish material for endless controversy in patent litigation and thera- peutical opinion. Methylal Methylal, CH 2 (OCH3)2, may be obtained by boiling aqueous formal- dehyde with methyl alcohol and a little sulphuric acid, but it is usually prepared by oxidizing methyl alcohol with manganese dioxide and sul- phuric acid. It is a pleasant-smelling liquid, specific gravity .855 at 15° C, boiling 42°, readily soluble in water, alcohol, and oils, and when dis- tilled with sulphuric acid is resolved into methyl alcohol and formaldehyde. It is used as a soporific administered in syrup or water, also injected in 10 per cent solution, and is used locally in liniments or ointments as a local anesthetic. Amyloform A condensation product of formaldehyde and starch, white, odorless powder, insoluble in ordinary solvents and possessing antiseptic properties. It is used as a substitute for iodoform. Formaldehyde Acetate Methylene diacetate, CH 2 (C2H 3 02)2, is a heavy colorless liquid, boil- ing 170° C, soluble in alcohol and in water with decomposition. It has antiseptic properties. It is prepared by the action of methylene iodide on silver acetate. Glutol-Schleich Glutol-Schleich or Formalin Gelatin, is a chemical combination of gelatin and formaldehyde. It is a white odorless powder, insoluble in water under ordinary con- ditions, but dissolved when heated with water under pressure, the solu- ALDEHYDES AND KETONES 579 tion thus produced gelatinizing on cooling. It is not changed by the action of acids, but is slowly decomposed in contact with living cells. It is to be used as an antiseptic dressing. Formicin Formicin is formaldehyde-acetamide, CHsCO-NH-.CEk-OH, a molecular compound of formaldehyde and acetamide. It is a slightly yellowish, thick, syrupy liquid, having a faint, formal- dehyde-like odor and a slightly acid, bitter taste. The specific gravity should be between 1.14 and 1.18 at 20° C. Formicin is soluble in water, alcohol, chloroform, and glycerin; it is nearly insoluble in ether. An aqueous solution (1 to 10) has an acid reaction on litmus. At 115° C. to 120° C. formicin dissociates. If 1 mil of an aqueous solution of formicin (1 to 10) is mixed with 1 mil of a mixture composed of equal volumes of stronger ammonia water, potassium hydroxide test solution and silver nitrate test solution, no immediate darkening should take place; but if the mixture is allowed to stand for some time, or is warmed, darkening occurs, due to the separation of metallic silver. Solutions of formicin liberate formaldehyde gradually at body tem- perature, and thus exert an antiseptic action. Fortoin — Methylene-Dicotoin Fortoin, CEkCCuHnO^, is a condensation product of cotoin and formaldehyde. Fortoin forms yellow, needle-shaped, tasteless crystals, melting at 211° to 213° C. It is insoluble in water, sparingly soluble in alcohol, ether, or benzol, but freely soluble in dilute alkalies, acetone, or chloro- form. It dissolves in cold concentrated sulphuric acid with an orange color, and on warming the solution becomes ruby red. It is used as an antidiarrheic in acute and chronic intestinal catarrh and in obstinate diarrheas. Formaloin This product is a yellow, amorphous, tasteless powder soluble in alkalies, with difficulty in alcohol and insoluble in water. It is a con- densation product of formaldehyde and aloin and it is used for the same purposes as aloin. Forman This is a colorless, unstable oily liquid, readily decomposed by water or moist air, prepared by the action of formaldehyde on menthol in the presence of hydrochloric acid gas. Chemically it is chlormethylmenthyl 580 ORGANIC SUBSTANCES ester, CioHigOCH^-Cl. It is soluble in oils and is used in catarrhal affec- tions either as an inhalant or on absorbent cotton. Formopyrin Methylenediantipyrin, (CnHnN20)2=CH2, prepared with formal- dehyde and antipyrin, forms colorless crystals, melting 176-177°, soluble in alcohol and almost insoluble in water. Ichthoform This product is prepared from formaldehyde and ichthyol, and is a dark-brown, practically odorless and tasteless powder, permanent and generally insoluble. Empyroform Empyroform is a condensation of birch tar and formaldehyde. According to the patent specifications birch tar is boiled with formal- dehyde solution and the hot liquid poured into hydrochloric acid. When cold, the solid mass is collected and washed until free from acid. It is a grayish-brown, almost odorless powder, insoluble in water, but soluble in acetone and chloroform. Empyroform is an antipruritic, sedative, and desiccant. Soap solutions containing formaldehyde are marketed under the name " Veroform." Resorcinoform This product results from the reaction of resorcinol and formaldehyde in the presence of hydrochloric acid, and is an amorphous currant-red powder with antiseptic properties. Hexamethylenetetramine, (CH 2 ) 6 N 4 This body should strictly be taken up with the amines, but it is more conveniently discussed at this point as it is a derivative of formaldehyde. It results from the reaction of ammonia with formaldehyde. 6CHOH+4NH 3 = (CH 2 ) 6 N+6H 2 It is official in our Pharmacopoeia, and is sold under its chemical name and by a number of trade names associated with the firms exploiting it including aminoform, cystamin, cystogen, formin, uritone, urotropin, etc. It occurs in the form of colorless, lustrous, odorless crystals, readily soluble in water and alcohol and slightly in ether. The aqueous solution ALDEHYDES AND KETONES 581 is alkaline. It sublimes at 263° C. without melting and with partial decom- position. It is precipitated by Mayer's reagent, mercuric chloride, tannin, bromin, . and other alkaloidal reagents. Bromin produces a brick-red precipitate, CeH^^Br-i, which on drying becomes yellow and is converted to the dibromide melting slightly below 200° C. One-tenth gram of the solid substance with .1 gram salicylic acid and 5 mils sulphuric acid gives a carmine-red color on warming. In the general scheme of qualitative analysis this body will remain in the aqueous solution through both of the acid and alkaline shake-outs. If a small portion of the solution which has been subjected to the regular treatment, is removed and acidulated, and if still found to give a marked precipitate with Mayer's reagent, the presence of hexamethylenetetra- mine may be suspected The solution should then be made strongly alka- line with sodium hydroxide and boiled until all the ammonia is dispelled, the hexamethylenetetramine being unaffected; it is then made acid with sulphuric acid and boiled again, preferably first under a reflux and then partly distilled, the distillate being tested for formaldehyde. The acid liquor is then treated with an excess of sodium hydroxide and boiled and if ammonia is now obtained the presence of the compound suspected is established. Puckner and Hilpert * use this method for estimating the substance. The liquid is first boiled with strong caustic alkali by which it is unaffected until all the liberated ammonia is driven off, then boiled with acid and finally with alkali, collecting the distillate in a known amount of standard acid and titrating back with alkali as in a Kjeldahl nitrogen determination. Hexamethylenetetramine may also be determined by precipitating it from acetic acid solution by mercuric chloride which yields the compound, C6H12N4 • 2HgCl2, this is washed with water containing mercuric chloride, dissolved in concentrated sodium chloride solution, the mercury precipi- tated by potassium hydroxide, filtered, the filtrate acidulated with sul- phuric acid and the regular Kjeldahl combustion and distillation prose- cuted. This method has been advanced by Schroter 2 for determining the body in urine. EVALUATION OF HEXAMETHYLENETETRAMINE TABLETS. W. O EMERY Reagents : A. Modified Nessler's Reagent, involving: (a) Solution of 10 grams HgCk, 30 grams KI and 5 grams acacia in 200 mils water, filtered through a pledget of cotton, and (6) Solution of 15 grams NaOH in 100 mils water. 1 J. Amer. Chem. Soc, 1908, 30, 1471. 2 Arch. exp. Path. Pharm., 64, 161. 582 ORGANIC SUBSTANCES B. Tenth normal iodin. C. Twentieth normal thiosulphate. Ascertain the weight of 20 or more tablets, triturate in a mortar to a fine powder and keep in a small capsule tightly closed with a cork or glass stopper. Weigh out .5 gram of the powdered product on a metal scoop or watch-glass, transfer with sufficient water to a round-bottom flask, add additional water to a total volume of 100 mils and finally 25 mils 10 per cent HCL Connect with a reflux condenser (preferably of the worm type) and boil gently fifteen minutes, then after cooling wash-out con- denser tube with a little distilled water and transfer contents of flask quantitatively to a graduated 250-mil flask, finally diluting to the mark with water. With a pipette withdraw 10 mils (containing in the case of a pure prod- uct the elements of .02 grams C6H12N4) of the solution so prepared to a 200-mil Erlenmeyer containing a mixture (chilled in ice water if avail- able) of 20 mils reagent A (a) and 10 mils reagent A (b), wash down neck of container with a jet of water from the wash bottle and allow to stand at least one minute. Now add 10 mils 40 per cent acetic acid in such manner that the inside of neck is completely washed by the reagent, mix quickly and thoroughly by rotating and tilting flask, and immediately run in from a burette 20 mils of B, then titrate with C (adding 5-10 drops starch solution toward the end of the operation) to the disappearance of the blue coloration. The final color of the solution is a pale straw- green. If preferred, the end-point may be determined on the reappear- ance of a faint blue coloration, induced by the addition of further iodin. The reaction taking place between formaldehyde and potassium mer- curic iodide in the presence of caustic alkali is given in the equation : CH 2 0+K2Hgl4+3KOH = Hg+HC02K+4KI+2H 2 In carrying out the method proper, unusual care is necessary in add- ing and mixing the several reagents with the preceding menstruum so that uniform solution shall result. This is effected by judicious rotation and tilting of flask, and at certain points also by washing down the neck of container with a jet of water. Addition of iodin should follow acidifi- cation with the greatest possible dispatch, on account of the fact that long standing of the mixture in the presence of free acetic acid invariably leads to low values for hexamethylenetetramine, due apparently to partial solution of colloidal mercury. The primary chilling of Nessler's reagent is advocated in order to minimize to the utmost any tendency toward secondary reactions, as also to avoid possible loss of iodin through undue increase in temperature on acidifying with acetic acid. Since the standard iodin (reagent B), employed has twice the strength of the thiosulphate (reagent C) , and 1 mil tenth normal iodin is equivalent ALDEHYDES AND KETONES 583 to .001167 gram hexamethylenetetramine, the quantity of this product in the aliquot under examination is readily calculated from the expression : ^-^N 0.001167 in which H = number of mils reagent C equivalent to 20 mils reagent B, 1 = number mils reagent C required to offset the unexpended iodin, and N= normality of reagent B. Derivati/es and Compounds of Hexamethylenetetramine There are many substances on the market claiming to be derivatives of hexamethylenetetramine, some of which are protected by patent. Some of these are claimed to be compounds with boric, citric, and other acids, with guaiacol and various phenols, with acid salts, sulphonic acid, etc. With certain compounds, simple treatment with chloroform is sufficient to remove the hexamethylenetetramine unchanged, and it is evident that the claim of possessing a new body is in some cases entirely unfounded. It is claimed that stable solutions of mercury and hexamethylenetetra- mine can be obtained by mixing the mercuric compound with a soluble albumin or the sodium salt of casein or an albuminate, and stirring into a large excess of 5 per cent soap solution. Hetralin Resorcinol-hexamethylenetetramine forms white crystalline needles, soluble in alcohol and water and decomposing above 160°. It is recom- mended as a diuretic and used in gonorrheal affections. Hexal Hexal is hexamethyleneamine salicylsulphonic acid, (CH 2 ) 6 N 4 • C 6 H 3 (OH)COOH ■ HS0 3 . It is a white, odorless, crystalline powder, readily soluble in water, slightly soluble in alcohol and difficultly soluble in ether, having an acid taste. A dilute aqueous solution of hexal gives a violet color with ferric chloride, a white precipitate with aqueous albumin solution, and an orange- colored precipitate with bromin water. With the exception of the tannic acid test, hexal responds to the identity tests of the U. S. Pharmacopoeia for hexamethylenemine. If .1 to .2 gram hexal is moderately heated with 5 mils concentrated sulphuric acid, a carmine-red color will be produced. 584 ORGANIC SUBSTANCES Hexal is claimed to be useful in chronic inflammations of the bladder and in urethritis. Hexamethylenamine Methylenecitrate — Helmitol Hexamethylenamine methylenecitrate, CeHgOyCC^^N/t, is a com- pound of hexamethylenamine with anhydromethylenecitric acid. It is a white, crystalline powder, melting with decomposition at 165 to 175° C, having an agreeable, acidulous taste and acid reaction. It is soluble in about 10 parts of water, but almost insoluble in alcohol and ether. By dilute acids and more easily by alkalies it is decomposed with the liberation of formaldehyde. On addition of 1 per cent solution of phloro- glucin to a solution of hexamethylenamine methylenecitrate, followed by sodium hydroxide, the intense rose-red color characteristic of the liber- ated formaldehyde is developed. It is used in cystitis, pyelitis, prostatic diseases, and urethritis. Saliformin Hexamethylenamine salicylate, (C^e^CelLrOH'COOH, is a weak salt of hexamethylenamine and salicylic acid. It is a white, crystalline powder, having an acidulous and disagree- able taste, readily soluble in water or alcohol. It is soluble in cold sulphuric acid without color, becoming crimson on heating. Its aqueous solution is colored deep green by copper sul- phate, violet by ferric chloride, and forms a yellow precipitate with bromin. It is decomposed with basic substances (soluble hydroxides, carbonates, etc.) and by strong acids. It is incompatible with salts of iron and other metals which form insoluble compounds with salicylates. It is said to be useful in cystitis, lithiasis, and bacterial affections of the urinary passages, also in gout, etc. Tannopin — Hexamethylen-tetramine Tannin — Tannon Tannopin, (Ci4Hi O 9 )3 • (CH 2 )eN4, is a condensation product of tannin with hexamethylenamine. It is a fine, fawn-colored and tasteless, nonhygroscopic powder, con- taining 87 per cent of tannin and 13 per cent of hexamethylenamine. It is insoluble in water, weak acids, alcohol, chloroform, or ether, but slowly soluble in dilute alkalies. On heating dry tannopin, it swells and gives off the odor of formaldehyde. The odor of formaldehyde is also developed on heating tannopin with dilute sulphuric or hydrochloric acid, while on boiling with sodium hydroxide solution it splits off ammonia. The clear aqueous filtrate from tannopin does not give a reaction with ferric chloride. ALDEHYDES AND KETONES 585 Tannopin has an astringent and antiseptic action in the intestine; it passes unchanged through the stomach, but being gradually decomposed by alkalies, it becomes effective in the intestinal tract, exerting the action of its two components. Urystamine is probably a mixture of Hthium benzoate and hexamethyl- enetetramine. Thial Hexamethylenamine oxymethylsulphonate is a white odorless pow- der, easily soluble in water and used as an antiseptic. Bromalin Hexamethylenetetramine bromethylate, C6Hi2N4C2H 5 Br. Forms colorless crystals, melting 200°, soluble in water and used as a nerve sedative. It is claimed that it causes no brominism. Iodoformin Iodoformin is claimed to be a compound of hexamethylenamine and iodoform containing 75 per cent of iodoform. It is insoluble in water and is used for the same purposes as iodoform. Iodoformal, CeH^NQHoICHsI Iodoformal is obtained by the action of ethyl iodide on iodoformin. It is lemon-yellow odorless powder insoluble in water. ACETALDEHYDE, CH 3 CHO Acetaldehyde is a colorless, mobile, volatile liquid, specific gravity .790 at 15°, boiling 20-21°. It has a peculiar penetrating and suffocating odor, and mixes with water, alcohol, and ether in all proportions. It is slowly oxidized to acetic acid on exposure to air, has powerful reducing properties, and on treatment with reducing agents is converted to ethyl alcohol. With hydroxjdamine it forms a crystalline oxime, and when shaken with a concentrated solution of sodium bisulphite, the crystalline addition product separates. It combines directly with diy ammonia, producing a colorless crystalline substance aldehyde ammonia, which is decomposed by acids. When warmed with caustic alkalies it is converted into a brown substance called aldehyde resin. Three well-defined polymerides are known — aldol, paraldehyde, and metaldehyde. Aldol, CH 3 CH(OH)CH 2 CHO, is produced by the action of dilute hydrochloric acid or zinc chloride at ordinary temperatures. It is a colorless, odorless liquid, miscible with water, and shows all the ordi- 586 ORGANIC SUBSTANCES nary properties of an aldehyde. It can be distilled unchanged under reduced pressure, but when distilled under ordinary pressure, or when treated with dehydrating agents it is converted into water and croton- aldehyde, CH 3 CH = CH-CHO. Paraldehyde, (C 2 H40) 3 , results when a drop of concentrated sulphuric acid is added to acetaldehyde. It is a colorless, pleasant-smelling liquid, specific gravity .995-. 998 at 15°, boil- ing 121-125° and solidifying in the cold. It is soluble in water, alcohol, ether, chloroform, and oils. It shows none of the ordinary properties of an aldehyde and its construction may be represented by the formula: O-CH— CH 3 ch 3 — ch/ No O-CH— CH 3 It is used as a stimulant, hypnotic, and antispasmodic, being employed for insomnia, and as an antidote for morphin poisoning. It is sometimes dispensed mixed with a fixed edible oil. Metaldehyde, (C 2 H£0)n, is produced by the action of acids at low temperatures. It crystallizes in colorless needles insoluble in water, is sub- limable without change, but on prolonged heating or by distilling with acids it is converted into acetaldehyde. S. S. Sadtler 1 has proposed a method for determining aldehydes based on the reaction with sodium sulphite whereby sodium hydroxide is liberated and titrated. For the determination of citral in lemon oil, from 5 to 10 grams of the sample are made neutral if necessary, treated with 25 to 50 mils of 20 per cent solution of sodium sulphite and neutral- ized with N/2 hydrochloric acid, using rosolic acid. The red color due to the free alkali is discharged by the acid, and the mixture kept hot and well agitated the titration with acid being continued as long as the color is reformed. The reaction is complete in one-half hour. C 9 Hi 5 COH+2H 2 0+2Na 2 S0 3 = C 9 Hi 7 COH(NaS0 3 ) 2 +2NaOH The reaction is available for the determination of vanillin, piperonal, and other aldehydes. The phenolic hydroxy 1 of the vanillin is neutral- ized by alkali, using rosolic acid, then sodium sulphite added and the titration with acid performed in the hot solution. The alkalinity of the sulphite must be determined and allowed for. Sadtler states that the reaction is complete and immediate with the fatty aldehydes. It will detect minute quantities of formaldehyde and is of value in detecting acetaldehyde in grain alcohol, and acetone in methyl alcohol. This procedure can be used for the determining acetaldehyde in the presence • 1 J. Frank. Inst., 1904, 157, 231. ALDEHYDES AND KETONES 587 of paraldehyde, first neutralizing the latter. Richter 1 has worked out the details which are as follows: Ten grams are shaken with 100 mils water, phenolphthalein added, and then N/1 potassium hydroxide until a pink color is obtained; 20 mils of sulphite solution (25 grams — 100 mils) are added and the liquid titrated with N/1 hydrochloric acid. A blank is run with 100 mils water and 20 mils of the reagent. Richter says that good commercial specimens of paraldehyde show less than 1 per cent of acetaldehyde, and if kept in full-stoppered bottles away from the light there is no need of any serious contamination. CHLORAL AND CHLORAL HYDRATE Chloral, CCI3CHO, is by far the most important derivative of acetal- dehyde from a medicinal point of view, and consequently to the analyst in this field. Chloral is not prepared by the direct action of chlorine on acetaldehyde, but is made from alcohol. The reaction is complicated, but chloral /OCsHs alcoholate is formed C-C13-CH , and on distilling this with sul- \)H phuric acid, chloral is obtained. It is purified by conversion to the hydrate and on distilling again with acid, the pure chloral results. Chloral with an equivalent amount of absolute alcohol gives chloral alcoholate, melting 48°, boiling 113-114°. It is a heavy, oily-liquid, specific gravity 1.50, boiling 95-97°, with a penetrating and irritating odor, insoluble in water, but uniting with it. In chemical properties it closely resembles acetaldehyde, having strong reducing properties, and combining directly with ammonia, sodium bisulphite, etc. It is converted on oxidation to trichloracetic acid. With small quantities of acid it is converted into a white amorphous modifica- tion called metachloral. When boiled with potassium hydroxide it is decomposed into chloroform and potassium formate. It gives the well- known carbylamine reaction when warmed with potash and anilin. Chloral hydrate is a hypnotic, and has long been used as a constituent of " Knock-out " drops. In medicine it is valuable on account of its hypnotic properties. It is used in acute fevers, cerebral congestions, inflammations, mania, delirium tremens, croup, insomnia, tetanus, strych- nin, and cocain poisoning, chorea, and convulsions, and should be looked for in preparations intended for these disorders. Externally it is employed in alleviating foul sores, irritating ulcers, and in remedies for destroying parasites. 1 Pharm. Zeit., 1912, 125. 588 ORGANIC SUBSTANCES It will be found usually in the form of syrups or elixirs, and often combined with bromides, Hyoscyamus, and Cannabis indica. In dan- druff removers it occurs in conduction with resorcinol. To a limited extent it is dispensed in a compressed tablet or in capsule form. Chloral and its derivatives are included in the list of inhibited drugs, and the label of a preparation containing them is required to bear a state- ment of the quantity present. When chloral is poured into water the oily mass is soon changed to colorless crystals of chloral hydrate, CCl3CH(OH)2, which is strictly speaking a chlorinated diatomic alcohol. This is the form in which chloral appears on the market. It has a peculiar characteristic odor, melts at 57-58° C, boils 97°, is readily soluble in water, alcohol, and the ordinary organic solvents including petroleum ether, in fixed and volatile, and is decomposed on distillation with sulphuric acid, chloral passing over. It does not polymerize nor does it give the rosaniline reaction of aldehydes, in fact the general aldehyde properties due to the carbonyl group are no longer apparent, which is to be expected. It liquefies when triturated with an equal quantity of menthol, camphor, thymol, or phenol. An aqueous solution of chloral hydrate reduces ammoniacal silver oxide and Fehling's solution. It slowly volatilizes. A solution of chloral dis- solves morphin, quinin, and other alkaloids. The liquefied product solidi- fies to a crystalline mass between 35 and 50°. It does not give the iodo- form reaction and is not acted upon when gently heated with nitric acid of specific gravity 1.2. Chloral alcoholate differs essentially from chloral hydrate and is not readily soluble in water, gives the iodoform test and is acted upon by nitric acid, specific gravity 1.2. A solution of pyrogallol in 66 per cent sulphuric acid gives a blue color when gently warmed with chloral, and ruby color with butylchloral, and a more or less violet to blue color with mixtures. On adding a large amount of water the blue color changes to yellowish and the ruby to violet. In the general scheme of analysis chloral hydrate will appear on shak- ing out the acid solution with petroleum ether, and will be entirely removed in the next or ether fraction. The residue left on evaporating the solvent will be a colorless, syrupy liquid which will finally crystallize unless there is too much water present. This residue will have the characteristic odor of the substance, will give the carbylamine reaction and an aqueous solu- tion will reduce ammoniacal silver oxide and Fehling's solution. Butyl- chloral hydrate is much more difficultly soluble in water than chloral hydrate and has a melting-point of 78°, does not give chloroform on treat- ment with alkali and reacts differently with pyrogallol. Some little care may be necessary to distinguish between chloral and its amido compounds, and before leaving a chloral hydrate residue the ALDEHYDES AND KETONES 589 analyst can well apply a few precautionary reactions. A small amount of the residue should be warmed with potassium hydroxide, and if there is no carbylamine odor it is almost certain that no amido substances are present. If, however, the odor is obtained it may indicate acetanilid, and in order to eliminate this contingency the residue should be heated in a small Erlenmeyer on the steam-bath with dilute sulphuric acid for an hour, not allowing the concentration to become great enough to produce charring, then diluted and shaken out several times with ether. The acid solution is warmed to drive off any dissolved ether and treated with bromin water which will throw out the tribromanilin bromide if anilin sulphate is present. The bromin compound must then be separated, washed, dried, and its melting-point determined. By this means any acetanilid will be hydrolyzed, and acetic acid and anilin sulphate produced, the latter remaining in the acid solution on shaking with ether to remove the chloral. Bromal hydrate can be distinguished from chloral hydrate, since it will give bromoform on warming with dilute alkalies. Bromoform boils 148-150° in contrast to chloroform, which boils 60-62°. Bromoform gives the carbylamine reaction, but when boiled with alcoholic potash it does not give a formate. CHBr3+3KOH+CYH 5 OH = 3KBr+CO+C2H4+3H 2 Chloroform gives triethyl formate, which, on treatment with tartaric acid and distilled, yields formic acid. Chloral hydrate, on boiling with magnesium oxide and water, gives chloroform and magnesium formate. Trichloracetic acid yields chloro- form, but no formic acid. Most of the methods advanced for the quantitative estimation of chloral depend upon the decomposition of the substances with alkalies and separating and measuring the chloroform produced. If the sample under investigation is a solid, the chloral hydrate should be dissolved out of the excipient with ether, the solvent evaporated rapidly but without undue heating, and the residue washed with water into a small distilling flask, which is fitted with a tube bent twice at right angles, and running into a graduate accurately calibrated. Four to five grams of slacked lime are then added to the distilling flask, which is gently heated, so that the chloroform evolved will be cooled in the tube, and collected in the gradu- ate. After the bulk of the chloroform has come over, the heat is increased until about 10 mils of water have distilled, and then the volume of chloro- form is read off. The meniscus can be broken by adding a little potassium hydroxide. The volume of the chloroform multiplied by 1.84 gives the grams of anhydrous chloral or by 2.064 the amount of chloral hydrate. A liquid mixture may be examined in the same general way, first removing any alcohol that may be present by distillation, and then shaking 590 ORGANIC SUBSTANCES out the chloral with ether from a slightly acid solution. If a previous qualitative test has shown little else than water and chloral, the solu- tion can be added directly to the distilling flask. If it is desired to assay a sample of chloral hydrate, a weighed sample is placed in a graduate and treated with strong potassium hydroxide solu- tion, keeping the mixture cool at first until the first violent reaction has ceased. The tube is then stoppered and shaken, and after two to three hours the volume of the chloroform determined. A residue of chloral hydrate can be titrated with alkali, using litmus as an indicator. It is dissolved in water and any free acid present neutral- ized with barium carbonate, the filtrate treated with a known excess of N/1 sodium hydroxide and titrated back with acid. One mil N/1 alkali = .1415 gram chloral or .1655 gram chloral hydrate. Chloral hydrate can also be determined by boiling with magnesium oxide and water under a reflux, whereby chloroform and magnesium form- ate result. The chloroform is then distilled, the aqueous solution acidi- fied with tartaric acid and the formic acid distilled with steam using the details and precautions prescribed on page 627, under the determination of formic acid. Self, 1 criticising the B. P. method of assaying chloral, recommends heating .3 gram of the sample with 1 gram aluminum powder or 2.5 grams zinc filings, 15 mils glacial acetic acid and 40 mils water for one-half hour under a reflux. The mixture is then filtered and after washing, the chlorine in the solution is determined. The detection of small quantities of chloral, especially in the presence of chloroform, bromoform, and trichloracetic acid, can be accomplished by dissolving the residue in water faintly acid with sulphuric acid, trans- ferring to a flask, adding a little zinc and closing the flask with cotton. When the evolution of hydrogen has ceased, the flask is warmed and the vapor escaping allowed to act on paper impregna/ted with sodium nitro- prusside and 5 per cent piperidin. A blue coloration indicates aldehyde formed by the reduction of the chloral. Trichlorethidene propenyl ether, CCl 3 CHO(OH)3C 3 H 5 This ether is a condensation product of chloral and glycerin and is marketed in a glycerine solution under the name " Somnos." Dimethylethylcarbinol chloral, CoHsCCHs^COCHOHCCls This product is sold under the name of " Dormiol," either in a 50 per cent aqueous solution, or in globules or capsules in an oil medium. It is soluble in alcohol, ether, and chloroform, reduces ammoniacal silver 1 Pharm. J., 1907, 79-4. ALDEHYDES AND KETONES 591 oxide similarly to chloral, and on treatment with caustic alkali is decom- posed with a precipitation of chloroform. It is gradually broken down by simply warming its aqueous solution or on exposure to the light. Bromal, CBr 3 CHO Bromal is a heavy yellowish liquid, specific gravity 2.30 at 15°, boiling 174° C, soluble in alcohol and ether, and forming the hydrate with water. Bromal Hydrate, CBr 3 CH(OH) 5 This body is closely related to chloral hydrate, it forms white deli- quescent crystals having a similar odor to chloral hydrate. It melts 53° C. and is soluble in water, alcohol, ether, and chloroform. It is employed for the same purposes as chloral, but will seldom be encountered in prac- tice. On warming with alkali it yields bromoform and a formate. Butyl-chloral, CH 3 CHC1CC1 2 CH0 Butyl-chloral is made by passing dry chlorine through acetaldehyde cooled to - 10° C. ; on fractional distillation of the product, the fraction boiling 163-165° C. is collected. It is a colorless, oily liquid, specific gravity 1.395 at 20° C, and soluble in alcohol, ether, and water. On oxidation with nitric acid it yields trichlorbutyric acid, melting about 60° and boiling 235-238°. Butyl-chloral Hydrate, CH 3 CHC1CC1 2 CH(0H) 2 The hydrate results on adding water to butyl chloral. It occurs in crystalline micaceous scales of a pungent odor, melting 78°, readily solu- ble in alcohol, ether and glycerin, sparingly soluble in water and only slightly in chloroform. It does not yield chloroform when heated with alkalies or lime water. Its use is limited, but in general it is given for the same purposes as chloral. Chloralurethane, CCl 3 CH(OH)(NH)COOC 2 H 2 This substance, also called uraline, ural, or uralium, is prepared by heating chloral with urethane (ethyl carbamate), CO(NH2)OC2H 5 , and then adding sucessively hydrochloric acid and acetic acid. It forms color- less crystals, melting 103°^ readily soluble in alcohol, water, and ether. Chloral formamide, CClsCHOHCONHo This product, also called " chloralamide," is official in our Pharmaco- poeia. It occurs as lustrous, colorless, odorless crystals, readily soluble in 592 ORGANIC SUBSTANCES ordinary organic solvents, glycerin, and water, melting 114-115°. It is decomposed when heated in solution. It is used as a hypnotic and analgesic, and should be suspected in remedies for certain forms of neuralgia and sleeplessness accompanying headache. Its melting-point is very close to that of acetanilid. Chloralimide, CC1 3 CH = NH Chloralimide occurs in colorless, odorless crystals, melting 153°, readily soluble in alcohol, ether, chloroform, and oils and insoluble in water. It is employed for the same purposes as the preceding substance. Chloralose — Anhydroglucochloral, CgHnClsOe Chloralose results from the action of anhydrous chloral on glucose. It forms colorless crystals, melting 183°, soluble in alcohol and slightly in water. It is claimed that this body will produce sleep without affecting the heart and without cumulative tendency. Galactochloral This body probably resembling the former in composition, occurs in lustrous leaflets, soluble in alcohol and insoluble in water. Hypnal Hypnal is an equimolecular mixture of chloral hydrate and antipyrin, and melts 67° C. It is readily soluble in water. Viferral Viferral is prepared from chloral and pyridin, and is a white powder, readily soluble in warm water, but not in water acidulated with hydro- chloric acid. It melts 150-155°. It is similar to if not identical with the substance called " Poly chloral," which is apparently a polymerized chloral, and readily converted by water into chloral hydrate. Chloral Acetone Chloroform This substance is made by heating together equimolecular quantities of chloral and trichlortertiary butyl alcohol or chloretone. The resulting product melts 65° and may be sublimed unchanged. It possesses a faint odor and taste resembling camphor, sparingly soluble in cold water, and is decomposed by acids into its components. Just how intimately the separate bodies are combined is as yet uncertain. ALDEHYDES AND KETONES 593 A solid polymeric form of chloral results when the oil is treated with anhydrous aluminum chloride. The resulting product is insoluble in alcohol, water, or acids, but dissolves in sodium carbonate solution. It gives chloroform on warming with alkali. Trichloracetic acid, CCI3COOH This substance would perhaps be more properly discussed under acids, but as it is in some respects a derivative of chloral, and in some of its chemical properties bears a resemblance to that body, it will be taken up now. It is obtained by oxidizing chloral with nitric acid, and on distillation the portion coming over at 195° is the pure acid. It boils at that tempera- ature, melts at 52-53° C, and forms deliquescent, colorless crystals, with a pungent, suffocating odor and freely soluble in water, alcohol, and ether. Hot alkalies decompose it into chloroform and a carbonate, chloral under similar conditions yielding chloroform and a formate. It will of course give the carbylamine reaction. Trichloracetic acid will be removed from an acid aqueous solution with ether, and may be recognized by its odor, boiling-point, and chemical properties. There are two other chloracetic acids, monochlor, melting 62° and boiling 185-187°, and dichlor, a liquid boiling 190-191°. Neither of them will give chloroform on treatment with alkali. All of the chloracetic acids are powerful escharotics, astringents, and hemostatics. The trichlor is the one generally used and will be found in wart and corn remedies, in liquids for local application in the nose and throat for the removal of growth, and for the removal of venereal growths, chancre, gleet, gonorrhea, etc., and for alleviating nose bleed. Trichlorbutyric acid, CH 3 CHC1CC1 2 C00H Trichlorbutyric acid is prepared from butylchloral by oxidation with nitric acid. It forms colorless needles, slightly soluble in water, melting above 60° and boiling 235-238° C. AROMATIC ALDEHYDES The aromatic aldehydes may be derived from the corresponding alco- hols by mild oxidation. Those with the carbonyl group attached to the nucleus differ in some particulars from those in which it is attached to the side chain, but in general their properties are similar, and those of the latter class resemble the aliphatic aldehydes very closely. Those with the aldehyde group in the nucleus do not reduce Fehling's solution, 594 ORGANIC SUBSTANCES do not form addition products with ammonia, and when shaken with alkali from a corresponding alcohol and acid. Benzaldehyde, C 6 H 5 CHO Benzaldehyde is a representative of the type with the carbonyl in the nucleus. It was formerly obtained by the decomposition of amygdalin, a glucoside occurring in bitter almonds, but is now prepared synthetically. It is a colorless liquid, boiling 179°, specific gravity 1.05 at 15° and volatile with steam. It has a characteristic odor, is sparingly soluble in water, but readily in organic solvents. It is completely oxidized in alcoholic solution to benzoic acid, which furnishes a simple method for its determination. Benzaldehyde is the chief constituent of oil of bitter almonds and other oils distilled from similar fruits. It is also a constituent of Cherry Laurel Water and shares its reputation with hydrocyanic acid, with which it endeavors to strike an equihbrium as benzaldehyde cyanhydrin. Determination of Benzaldehyde, U. S. P. — Dissolve about 3 mils of freshly redistilled phenylhydrazine in 60 mils of alcohol and titrate 25 mils of this solution, which must always be freshly prepared, with half- normal hydrochloric acid V. S., using methyl orange TVS. as indicator. To about 1 gram of the Oil of Bitter almond, accurately weighed, add 25 mils of the phenylhydrazine solution just prepared and allow it to stand for thirty minutes. Add a drop of methyl orange T. S., and acidify the mixture by adding a measured excess of half -normal hydrochloric acid. Filter the mixture and wash the precipitate with small portions of dis- tilled water until the washings cease to redden blue litmus paper. Then titrate the excess of hydrochloric acid in the filtrate with half -normal potassium hydroxide V. S. and subtract the number of mils of the half- normal hydrochloric acid V. S. used in titrating the 25 mils of phenyl- hydrazine solution; the difference multiplied by .053 gives the weight of benzaldehyde. Method of Hortvet and West. — Measure 10 mils of the extract into a 100-mil flask, add 10 mils of a 10 per cent sodium hydroxide solution and 20 mils of a 3 per cent hydrogen peroxide solution, cover with a watch- glass and place on a water-oven. Oxidation begins almost immediately and should be continued from five to ten minutes after all odor of benzal- dehyde has disappeared, which usually requires from twenty to thirty minutes. If nitrobenzol be present, it will be indicated at this point by its odor. When the oxidation of the aldehyde is complete, remove the flask from the water-oven, transfer the contents to a separatory funnel, rinsing off the watch-glass, add 10 mils of a 20 per cent sulphuric acid solution, and cool the contents of the funnel to room temperature under ALDEHYDES AND KETONES 595 the water tap. Extract the benzoic acid with three portions of 50, 30, and 20 mils of ether, respectively, wash the combined extracts in another separatory funnel with two portions of from 25 to 30 mils of distilled water, or until all the sulphuric acid is removed. Filter into a tared dish, wash with ether, allow to evaporate at room temperature, and finally dry over- night in a desiccator, and weigh. The per cent of benzaldehdye (B) is obtained from the weight of the acid (W) by the following formula: 0.869X10XIT 1.045 If desired the benzoic acid may be titrated, and the benzaldehyde calculated from the amount of standard alkali required for neutralization. The process is as follows: Dissolve the benzoic acid obtained as above described, except that it need not be dried in a desiccator, in 95 per cent alcohol, made neutral to phenolphthalein with N/10 sodium hydroxide, dilute with an equal volume of water, and titrate with N/10 sodium hydro- oxide, using phenolphthalein as indicator. The per cent of benzaldehyde (B) is calculated from the mils of N/10 alkali (7) by the following formula: 7X0.01061X10 £= 1.045 Cinnamic Aldehyde, C 6 H 5 CH : CHCHO This aldehyde is the chief constituent of oils of cinnamon and cassia. It is a yellowish oil with a characteristic odor, boiling about 245° C. under ordinary pressure with partial decomposition or at 128-130° at 20 mm. pressure, readily soluble in all the organic solvents, from which it may be extracted by shaking with sodium bisulphite solution. It oxidizes gradually and samples which have stood for any length of time will con- tain free cinnamic acid. Oxidation with peroxide converts it to cinnamic acid with the simultaneous formation of a little benzoic. Estimation, U. S. P. Method. — Introduce 10 mils of the oil into a 200-mil flask with a long graduated neck (cassia flask) by means of a pipette, add 50 mils of a saturated solution of sodium sulphite, which has been carefully rendered neutral to phenolphthalein by means of acetic acid, heat the mixture in a bath containing boiling water and shake the flask repeatedly, neutralizing the mixture from time to time by the addi- tion of a few drops of dilute acetic acid. When no coloration appears, upon the addition of a few more drops of phenolphthalein and heating for fifteen minutes, cool, and when the liquids have separated completely, add sufficient of the sodium sulphite solution to raise the lower limit of the oily layer within the graduated portion of the neck and note the volume 596 ORGANIC SUBSTANCES of the residua] liquid. It shows not less than 80 per cent by volume, of cinnamic aldehyde. It is found that cinnamic aldehyde, both pure, and as it occurs in cinnamon and cassia oils, may be quantitatively precipitated in the form of semioxamazone : CeHs-CH : CH-CH : N-NHCO-CONHs, by treating an aqueous suspension with a solution of semioxamazide in hot water. About .10 gram of the aldehyde is emulsified by agitation with 100 mils of water and treated with .25 to .35 gram of semioxamazide dissolved in 15 mils of hot water; the mixture is well shaken together, occasionally, for three hours, then allowed to stand for twenty-four hours. The crys- talline cinnamic-aldehyde semioxamazone is then collected on a tared Gooch filter, washed with cold water, dried at 105° C. for about four or five hours, then weighed. The weight of semioxamazone multiplied by the factor .6083 gives the amount of cinnamic aldehyde present. For the determination of the amount of aldehyde in cinnamon and cassia oils, from .15 to .2 gram is employed. To determine the amount of cinnamic aldehyde in cinnamon or cassia barks, from 5 to 8 grams of the finely ground material are distilled with steam, until about 400 mils of distillate have been collected. The volatile oil is extracted from the distillate by shaking out three or four times with ether, and after distilling off the ether, the oil is emulsified and treated with semioxamazide as described above. Salicylic Aldehyde, C 6 H 4 (OH)CHO O-hydroxybenzaldehyde, sometimes called " salicylous acid " may be obtained by oxidizing salicin with chromic acid. It possesses the proper- ties of a phenol and an aldehyde. It is a colorless oil with a penetrating odor, boiling 196°, specific gravity 1.165-1.172 at 15° C, somewhat soluble in water to which solution ferric chloride imparts a violet color, and dis- solving in all the ordinary organic solvents. Salicylic aldehyde occurs naturally in flowers of Spiraea ulmaria. The p- and ra-aldehydes are solids, melting 116° and 104° respectively. Salicylic aldehyde on treatment with sodium acetate and acetic anhy- dride is converted to coumarin, the odorous principle of tonka bean, Anisic aldehyde, C 6 H 4 (OCH s )CHO Anisic or p-methoxybenzaldehyde is obtained on oxidizing anethole, C6H4(OCH 3 )CH : CH : CH 3 , from oil of anise. It is a colorless oil with a penetrating odor boiling 248°. ALDEHYDES AND KETONES 597 Cuminic Aldehyde, C 6 H 4 (CH 3 )2CHCHO Cuminic or paraisopropyl benzoic aldehyde, incorrectly called cuminol, is the constituent of oil of cumin, to which it owes its odor and more prominent properties, and also occurs in oil of Roman chamomile. It is a yellowish oil with a persistent odor, and acrid burning taste, specific gravity .972 at 13°, boiling 232° or at 109.5° under 13.5 mm., soluble in alcohol and ether. Vanillin, C 6 H 3 OH • OCH 3 CHO 4:3:1 Methyl protocatechuic aldehyde or vanillin is one of the valuable con- stituents of vanilla beans, and also occurs in Siam benzoin and asafetida. It is not prepared in a commercial way from either of these sources, but from eugenol, an aromatic unsaturated phenol occurring in oil of cloves. It occurs in colorless prisms having an aromatic odor and a vanilla- like taste, melting 80-81°, boiling 285°, subliming when cautiously heated, slightly soluble in water and readily in the organic solvents. Its aqueous solution gives a blue color with ferric chloride. Vanillin possesses the characteristics of both a phenol and an aldehyde, and is therefore removed from its solution in organic solvents by both alkalies and sodium bisulphite. It is used to a limited extent in medicine as a tonic, stimulant, and aphrodisiac, and its presence is recognized without difficulty by its characteristic odor. Coumarin of course has an odor which simulates that of vanillin, but may be distinguished from the latter as it is not removed from its solution in ether by sodium hydroxide. Vanillin reduces ammoniacal silver oxide. When heated with dilute hydrochloric acid under pressure to 200° it yields protocatechuic aldehyde and methyl chloride. When fused with potash, protocatechuic acid results. On exposure in a moist or finely divided state it is oxidized to vanillic or methylprotocatechuic acid, melting 207°, which gives no color with ferric chloride. It yields vanillyl alcohol melting 115° on reduction. Vanillin gives a characteristic color when heated with hydrochloric acid and phloroglucinol. It gives a deep-bluish violet color when rubbed with resorcinol and hydrochloric acid. Vanillin as now found on the market is usually quite pure, but it was formerly contaminated with acetyl isoeugenol, due to incomplete purifica- tion, and it also was sophisticated by admixture with benzoic acid and acetanilid 598 ORGANIC SUBSTANCES Folin's Method for Determining Vanillin. — Solutions Required: (1) An aqueous solution of pure vanillin to be used as a standard. This should be made of such a strength that 10 mils contains 1 mg. of vanillin. (2) The phosphotungstic-phosphomolybdic acid reagent, prepared as follows: To 100 grams pure sodium tungstate and 20 grams phosphomo- lybdic acid (free from nitrates and ammonium salts) add 100 grams syrupy phosphoric acid (containing 85 per cent H3PO4) and 700 mils water; boil over a free flame for 1| to 2 hours; then cool, filter if necessary, and make up with water to a volume of 1 liter. An equivalent amount of pure molybdic acid may be substituted for the phosphomolybdic acid. (3) A solution of pure sodium carbonate saturated at room temper- ature. (4) A solution containing 5 per cent basic and 5 per cent neutral lead acetate. Vanillin (and also other mono-, di-, and trihydric phenol compounds) when treated in acid solution with the phosphotungstic-phosphomolybdic reagent above described gives on the addition of an excess of sodium car- bonate a beautiful deep-blue color admirably suited for quantitative colorimetric work. Five mils of the vanilla extract to be examined are transferred by means of a pipette to a 100-mil volumetric flask and about 75 mils cold tap water are added: 4 mils of the lead acetate solution are then poured in and the mixture made up to volume with water. The contents of the flask are then rapidly filtered through a folded filter paper; and 5 mils of the filtrate are transferred by means of a pipette to a 50-mil volumetric flask. In another 50-mil volumetric flask is placed 5 mils of the standard vanillin solution; then 5 mils of the phosphotungstic- phosphomolybdic reagent is added to each flask, the reagent being allowed to run down the neck of the flasks in order that any vanillin adhering thereto may be washed down. After shaking, the flasks are allowed to stand for five minutes and are then filled to the mark with saturated sodium carbonate solution. After inverting the flasks two or three times in order that the contents may become thoroughly mixed, they are allowed to stand for ten minutes, by which time the precipitation of sodium phos- phate is complete. The contents of the flasks are then rapidly filtered through a folded filter paper and the color of the resulting clear deep-blue solutions compared by means of a Dubosc colorimeter. The standard solution is best placed at 20 mm. as experiment has shown that the color produced by the amount of vanillin contained therein (1 mg. in 100 mils) is most accurately and easily read at this point. In this, as in all other colorimetric methods, a slight cloudiness of the solution to be read, by cutting off more light than the standard, gives ALDEHYDES AND KETONES 599 a reading much too low, with correspondingly high results; consequently no solution should be read which is not absolutely clear after filtration. The calculation of the results is not complicated. When 5 mils of the solution (previously diluted 5 : 100) is taken, this corresponds to .25 mil of the original solution. If 10 mils are taken they correspond to .5 mil of the original. Since .5 mg. vanillin is used as a standard and with the standard set at 20 (mm.) .5X20/5= X where R is the colorimeter reading of the unknown and X is the amount of vanillin in mgs. present in the volume of the original extract used in the final color comparison; 100 X divided by the volume of the extract taken expressed in mgs. gives the result in grams per 100 mils. Piperonal CHO \/\ CeHs >CH2 NT This substance, which is chemically the methylene ester of proto- catechuic aldehyde, is also known as heliotropin. It may be obtained by the gradual addition of potassium permanganate to a solution of potassium piperate, obtained by the fusion of piperin, and forms white, shiny crys- tals with a pleasant characteristic odor of heliotropin, melting 37°, slightly soluble in water, readily in alcohol and ether. It does not keep well except in alcoholic solution. It is used medicinally as an antiseptic and antipyretic, and will be found in remedies for skin diseases and fevers. Piperonal is now made from safrole, C3H51 by saponifying and then oxidizing with permanganate and sulphuric acid. When heated to 200° under pressure with dilute hydrochloric acid it gives protocatechuic aldehyde and carbon. Piperonal may be adulterate.d with vanillin and products formed dur- ing its manufacture. KETONES As medicinal agents the ketones of the aliphatic series have little importance, acetone is employed as a solvent and vehicle to some extent and methylisopropyl ketone has hypnotic properties. Of the aromatic ketones acetophenone and benzophenone with some of their derivatives, 600 ORGANIC SUBSTANCES have attained considerable importance, and the cyclic ketone camphor is a valuable medicinal agent. In the aliphatic series the ketones form an homologous series isomeric with the aldehydes, and are closely related to them in all reactions affect- ing the carbonyl group, which is common to both classes. Ketones form crystalline compounds with bisulphite, and oximes with hydroxylamine, and also react with phenylhydrazine and hydrocyanic acid. They are produced by the oxidization of secondary alcohols. They differ markedly from the aldehydes on oxidation, for, while the aldehydes are oxidized with ease to an acid containing the same number of carbon atoms, the ketones are only acted upon by stronger oxidizing agents, and are broken up, yielding products containing a smaller number of carbon atoms. Ketones do not reduce ammoniacal silver, nor restore the color to fuchsin bisulphite, neither do they polymerize though they form condensation products under certain conditions. Futhermore they do not form addi- tion products with ammonia nor combine with alcohols to form acetals. The lower members of the ketone series are colorless, mobile, odorous, volatile liquids soluble in water, alcohol, and ether. As the number of carbon atoms increases, the boiling-point rises and the solubility in water decreases. The higher members are heavy solids. Ketones give the cor- responding secondary alcohols on reduction. A secondary alcohol is not the sole product of reduction, but is usually accompanied by varying quantities of pinacones, acetone for example yielding acetone pinacone, (CH 3 )2C(OH)-C(OH)(CH 3 )2. Pinacones on distillation with dilute sul- phuric acid, yield pinacolines, that from acetone pinacone is a colorless liquid boiling 100° and having a menthol-like odor. Ketones are acted on by phosphorus pentachloride with formation of dihalogen derivatives of paraffins. When treated with dehydrating agents they undergo a form of condensation with elimination of water, two or more molecules taking place in the reaction, thus acetone gives mesityl oxide, CeHioO, and phoron, C9H14O. Acetone, CH 3 COCH 3 Acexone has a limited use in medicine as a mild alterative and anthel- mintic, and locally in certain forms of irritation where it is administered as a liniment. It is also used as a vehicle and does not have to be declared on the label. In liniments intended for local application it will be found combined with extracts and oils of arnica, calendula, turpentine, cade, and similar products, thujone, camphor, etc. Some of these mixtures are recommended as bactericides and for the absorption of calluses, tumors, goiter and like growths. ALDEHYDES AND KETONES 601 Acetone is a colorless, mobile liquid, specific gravity .792 at 20° C, boiling 56-57° with a peculiar, characteristic ethereal odor, and miscible in all proportions with water, alcohol, ether, chloroform, and volatile oils. When shaken with concentrated sodium bisulphite, it forms a crystalline compound which is readily soluble in water but insoluble in alcohol, and decomposed by dilute acids or alkalies. It forms acejxixime with hydroxylamine, a crystalline substance melting 59° C. With phos- phorus pentachloride it yields beta-dichlorpropane, (CH^CC^. Acetone gives the iodoform reaction in the cold. It does not reduce ammoniacal silver, nor give the rosaniline test. WTien saturated with dry hydrogen chloride it yields mesityl oxide and phoron, and when distilled with concentrated sulphuric acid it yields mesitylene, a derivative of benzol. Mesityl oxide is a colorless oil, boiling 130° C. with a menthol odor. Phoron is a colorless, crystalline solid melting 28°, and boiling 196°, with a pleasant aromatic odor. Both sub- stances are reverted to acetone on boiling with dilute sulphuric acid. Mesitylene CH 3 CH3V /CH3 is symmetrical trimethylbenzene, a colorless, mobile, fragrant liquid boiling 163°. When molecular proportions of acetone and chloroform or acetone and bromoform are treated with caustic alkalies, chloretone melting 80-81° and brometone melting 167° are found respectively. Both of these substances are trichlor and tribrom derivatives of tertiary butyl alcohol. On chlorinating acetone, monochloracetone, CH3COCH2CI, is one of the products. It is a colorless, pungent liquid, specific gravity 1.162 at 16°, boiling 105-106°, miscible with alcohol, ether, and chloroform and insoluble in water. For the detection of acetone, the distillate from a mixture should be employed, and if the distillate contains any essential oils they should be removed by shaking out with salt and petroleum ether, and the salt solu- tion again distilled. If acetone is present, the distillate will give a pre- cipitate of iodoform in the cold on adding a little sodium hydroxide and iodin solution. It will also give characteristic tests with salicylaldehyde and sodium nitroprusside. The former is carried out as follows: 10 mils of the liquid are treated with 1 gram of solid potassium hydroxide, and 10 drops salicylaldehyde and warmed to 70° C. In presence of acetone a purple-red contact ring develops. If the hydroxide is all dissolved 602 ORGANIC SUBSTANCES before the reagent is added, the liquid becomes yellow, reddish and purple- red The Nitroprusside Reaction. — Shake five drops of the ketone with 2 mils of cold water. If the substance does not dissolve completely, filter through a wet filter. Add to the clear solution two drops of a 1 per cent aqueous solution of sodium nitroprusside, and then two drops of sodium hydroxide solution (1 : 10). Without any unnecessary delay, carefully note the color, and then quickly divide the solution into two equal portions, a and 6, in small glass " weighing-tubes." To portion b add three drops of glacial acetic acid, and immediately note the color. Allow both solutions to stand for twenty minutes, and again carefully compare the color of each with the color standard. Many of the aldehydes as well as ketones give colorations in this test; but its most important practical application is its use as a convenient specific reaction for acetone and acetophenone. It distinguishes these ketones readily from all related ketones with which either is likely to be confused. In the case of acetone, portion a at first is orange, but changes to a clear yellow within twenty minutes. Portion b after the acidification with acetic acid is a red when viewed against a white background, with a very slight tendency to purple, that is most noticeable when the solu- tion is viewed by a strong transmitted light. This hue will be found unchanged at the end of twenty minutes, though its intensity will have fallen about one tint. The persistency of this hue in acetic-acid solution is the most characteristic part of the test when used to distinguish acetone from its homologues. In the case of acetophenone, the color of portion a is at first red with a very slight tendency to violet-red, just as in part b of the acetone test after acidification. This changes to yellow before the end of twenty minutes. Portion b upon acidification with acetic acid changes at once to a strong blue, whose hue is not materially changed at the end of twenty minutes, although it will have faded nearly one tint. The most characteristic part of the acetophenone test is the strong blue coloration of portion b. Homologues of acetophenone, CH 3 CO-R, like methyltolyl- and methylxylyl ketone, give pale violet or bluish color- ations. Fatty aromatic ketones, like ethyl-phenyl ketone, which contain no methyl radical in combination with CO * R, appear not to give any blue coloration at all. Sodium-nitroprusside solution does not keep very well, and should not be more than a few days old when used. Method for the Determination of Methyl Alcohol and Acetone in Drug Products. — A measured portion of the sample is diluted and filtered if deemed advisable and the whole or a convenient aliquot distilled into ALDEHYDES AND KETONES 603 such a volume that the distillate shall contain not more than 30 per cent volatile matter other than water. If volatile oils are present, the sample, either before or after dis- tillation, is freed from them by one of the following methods : (a) Shake with magnesium carbonate and filter, taking precautions to avoid loss by evaporation. (6) Saturate with salt and shake with petroleum ether. Separate the aqueous layer and if necessary repeat once or twice with fresh petro- leum ether. Wash the successive or combined petroleum ether portions with saturated salt solution and add the wash water to the main liquid and distill. Acetone. — An appropriate aliquot of the distillate is added to a con- venient volume of a solution containing approximately 140 grams potas- sium iodide and 114 grams sodium hydroxide per liter. An excess of a standardized solution of sodium hypochlorite is introduced, and the con- tainer stoppered and shaken for at least one minute. The solution is then acidified with dilute hydrochloric acid, care being taken not to allow the mixture to become hot. An excess of a standardized solution of sodium thiosulphate is introduced and the excess determined by means of the sodium hypochlorite solution, starch solution being used as indicator. Six atoms of iodin convert one molecule of acetone into iodoform. Methyl Alcohol. — An appropriate aliquot of the distillate is freed from acetone by conversion into iodoform with iodin and alkali. The iodo- form filtered off or shaken out with petroleum ether or chloroform, the solvent being washed with saturated salt solution and the washings added to the main liquid. If preferred, a combination filtration and shake-out method may be used to eliminate the iodoform. The liquid is then dis- tilled, the distillate diluted to a definite volume and the methyl alcohol estimated from the refractive index as given on page 535. For approxi- mate results the density tables for ethyl alcohol may be used. Determination of Acetone by the Mercuric Iodide Method. Deniges. 1 — The reagent is prepared by dissolving 5 grams of mercuric oxide in 100 mils of water to which 20 mils of sulphuric acid have been added. Acetone in aqueous solution may be detected by adding 2 mils of this reagent to 2 mils of the solution in a test-tube and plunging the tube into boiling water. If no acetone is present, no precipitate will form within ten minutes. If the acetone is in alcoholic solution, water must be added prior to the addition of the reagent. Acetone may be estimated by taking 25 mils of the solution containing it — first diluting with water if the solution is an alcoholic one — adding 25 mils of the reagent, and cork- ing tightly in a strong flask of 90 mils capacity. The flask is set in a water- bath, which is raised to the boiling-point, and kept boiling for ten minutes. 1 J. Soc. Chem. Ind., 1899, page 179. 604 ORGANIC SUBSTANCES The flask is then removed from the bath, allowed to cool, and the pre- cipitate is collected on a weighed filter, washed with cold water, and dried. The weight of the precipitate multiplied by .06 (theoretically .0584) gives the weight of the acetone in the 25 mils of solution taken. Methyl alcohol and acetone can be detected in tincture of iodin by destroying the iodin with thiosulphate and distilling off a few mils through a long vertical condenser bent at about 50 cm. from the flask. Part of the distillate is treated according to the methods for detecting methyl alcohol and another portion tested for acetone. Determination of Acetone in Presence of Ethyl Alcohol. — A portion of the sample, containing about .05 gram of acetone, is placed in a 750-mil flask, 300 mils of freshly prepared lime-water is added, the flask is closed loosely with a rubber stopper, and its contents heated to 35° C; 5 mils of N/5 iodine solution is then added, drop by drop, and after shaking for five minutes, a second 5 mils is added, and so on until 40 mils in all has been introduced. After ten minutes, starch solution is added, the mix- ture cooled, acidified with 15 mils of N/1 sulphuric acid, and the excess of iodin titrated with N/10 thiosulphate solution. The number of mils of N/5 iodin solution used is multiplied by .00193 to obtain the quantity of acetone in the portion of the sample taken. If, during the addition of the iodin, the color persists after thorough agitation, more lime-water should be added. About .8 mil of N/5 iodin is absorbed by 1 mil of ethyl alcohol. When the sample contains only about 1 part of acetone and 100 parts of ethyl alcohol, the results are not very trustworthy, but in samples containing 1 part of acetone and 10 parts of ethyl alcohol the results are accurate and concordant. Acetone-resorcinol When a mixture of acetone and resorcinol is treated with hydrochloric acid gas, small prisms melting 212-213° having the composition C15H16O4 -I-H2O are produced. The product is insoluble in water, alcohol, ether, and chloroform, but dissolves in alkaline solutions. It is used as an antiseptic. Benzylideneacetone, C 6 I16h = CHCOCH3 This product, known as methyl cinnamyl ketone, methyl styrylketone, or acetocinnamone, forms colorless crystals melting 42° with a cumarin odor. It is soluble in the ordinary organic solvents. Salacetol, C 6 H 4 (OH)C0 2 CH 2 COCH3 It forms fine white to faintly reddish needles, melting 71° C, soluble in alcohol, ether, chloroform, fixed oils, and slightly in water. It is used as an antiseptic and antirheumatic. ALDEHYDES AND KETONES 605 Sodium Lygosinate, CO = (CH : CHC 6 H 4 ONa)27H20 This substance is the sodium salt of dioxy-dibenzal acetone. It occurs in glossy, greenish prisms, soluble in cold alcohol, easily soluble in hot alcohol and in glycerin. Its aqueous solution has a ruby-red color and is alkaline in reaction. On ignition, 1 gram of sodium lygosinate leaves a residue of sodium carbonate weighing .243 gram. From the aqueous solution acids precipi- tate a thick yellow precipitate of diortho-cumarketone. The solution is fairly stable when kept in a cool place, protected from the air, and is not decomposed on boiling, but is decomposed by weak acids, even the car- bonic acid of the air. Its powder produces sneezing. It is used as an antiseptic and bactericide in gonorrhoea and similar ailments. Methyl heptenone, CH 3 C(CH 3 ) =CHCH 2 CH 2 COCH 3 Methyl heptenone is an unsaturated ketone found in certain oils such as linalce, citronella, and lemon-grass. It is a colorless, mobile, inactive liquid with an amyl acetate-like odor. It boils 170-174°, readily forms a bisulphite compound and a semicarbazone melting 136-138°. AROMATIC KETONES The only aromatic ketones of importance in medicine are acetophenone camphor and thujone, though carvone and fenchone will sometimes occur as the flavoring principles in some elixirs and cough remedies. The ketones have the general formula R — CO — R', where R and R' represent different or identical radicles, one of which must of course be aromatic. Acetophenone, C 6 H 5 COCH3 Acetophenone or phenyl methyl ketone is known in medicine under the name of Hypnone, and is employed as an hypnotic for insomnia. It occurs in laminary crystals, melting 14° C, so that it will often be encountered as a liquid, and boiling at 202°. It has a pungent taste and an odor recalling that of orange blossoms. It is soluble in alcohol, ether, chloroform, fatty oils, and to a slight extent in water. On reduction it yields phenyl methyl carbinol, C6H4CH(OH)CH3, and on oxidation it is resolved into benzoic acid and carbon dioxide. It reacts with hydroxylamine to form an oxime, and with phenyl hydrazine to give an hydrazone. Its low melting-point, odor and ketone-like properties are sufficient for its identification. 606 ORGANIC SUBSTANCES Benzophenone, C 6 HoCOC 6 H 6 This body forms crystals melting 48-49°. Trioxybenzophenone, C 6 H40HCOC 6 H 3 (OH)3 Trioxy benzophenone or salicylresorcinol ketone, is obtained by the interaction of salicylic acid and resorcinol. It melts 133° C. and is slightly soluble in water, but dissolves in hot alcohol and benzol. It is used as n antiseptic, antipyretic, and analgesic. Oxyphenylbenzylketone C 6 H 5 CH(OH) COC 6 H 5 This ketone, which is known as Benzoiin and bitter almond oil cam- phor, is a reaction product of benzaldehyde, potassium cyanide, and. ethyl alcohol. It forms colorless crystals, melting 135-137°, soluble in alcohol and hot water. It has antiseptic properties and is sometimes used in ointments for ulcers and varicose veins. Lowry in the new edition of Allen divides the cyclic ketones into four groups. a. CioHigO group, with a single ring: type menthone. b. CioHi 6 group, with a ring and a double bond or two double bonds: type camphor. c. C10H14O group, with a ring and two double bonds, two rings and one double bond, or three rings. d. Ketones with more or less than 10 carbon atoms such as matico- camphor. Carvone, C 10 Hi 4 O CH3 CH2 v i, H 2 C CH 2 HC C=0 V I CHO This ketone occurs in the d-form in caraway and dill oils and in the Worm in spearmint oil. None of these oils are of special interest to the ALDEHYDES AND KETONES 607 drug chemist. At the present time by far the greater amount of spear- mint oil is used in this country as a flavoring agent for chewing gum. Carvone is a colorless liquid with a strong odor suggestive of caraway. The d-form boils 224° C., specific gravity .9598 at 20° (a)n = +62.07°, the Z-form has practically the same constants with a minus rotation. It does not add bisulphite, but yields a well crystallized oxime, melt- ing 72°, inactive form 93°. Its phenylhydrazone melts 109-110° and its semicarbazide 54-56°. It also forms a crystalline compound with hydro- gen sulphide when an ammoniacal alcoholic solution is treated with this gas. For the determination of carvone in oil of spearmint the following methods appear to give satisfactory results : Walther Method. — Two to 5 grams of carvone or the carvone-bearing oil are placed in a wide-neck flask and 10 grams of a freshly prepared aqueous solution (2:3), of hydroxylamine hydrochloride added. Then add 25 mils aldehyde free absolute alcohol and 2 grains bicar- bonate sodium, connect the flask with a return-flow condenser, and heat to gentle boiling on a water-bath. After cooling to 25°, add 6 mils HC1 (1.12), and transfer to a 500-mil volumetric flask, rinsing out the condenser and flask with dilute HC1, followed with water. Filter, and in 25-50 mils of the filtrate titrate the excess of hydroxylamine. The titration of the hydroxylamine is carried out as follows: Methyl orange is added (about 1 drop), and the mineral acid neutral- ized with alkali. Then phenolphthalein is added and the hydroxylamine titrated with N/10 NaOH. The difference between the titration corresponding to the weight of hydroxylamine taken and that corresponding to the hydroxylamine left represents the amount converted into carvoxime. Each mil of N/10 NaOH is equivalent to .015 gram carvone. Nelson 1 finds this method satisfactory for determining pulegone, thujone, menthone, and camphor, but not fenchone. H. Labbe Method. — This method rests on the fact that carvone is dis- solved easily in a boiling solution of sodium bisulphite with the formation of a dihydro-di-sulphonate, of which the constitution has been established. First Method of Determination. — Five grams of the oil are placed in a little flask, fitted with a ground-in condenser, and about 15 grams of sodium bisulphite dissolved in water with Na2C03 are added. To render the boiling regular, a few pieces of porcelain are put in the flask. After 1| hours boiling, allow to cool thoroughly, and take up the residual oil with ether, washing out condenser and flask with the same solvent, and sepa- rate the aqueous layer in a small separatory funnel. 1 J. Ind. Eng Chem., 1911, 3, 588. 608 ORGANIC SUBSTANCES The ether solution is dried carefully with anhydrous sodium sulphate, filtered into a small weighed flask, the major portion of the ether evaporated in a partial vacuum, and the last traces by gentle heating. The increase in weight gives the hydrocarbons, or constituents not carvone. Second Method of Determination. — Since carvone on simply heating with a solution of sodium bi-sulphite and sodium carbonate furnishes a dihydro-di-sulphonate derivative which is very soluble, one is able, by using a titrated solution of bisulphite, to calculate from the dimunition in strength in SO3 after boiling, the proportion of carvone. To titrate the solution of bisulphite before and after, a centinormal solution of iodin in potassium iodide is used, which, as has been demon- strated has no action on the dissolved carvone derivative. One gram to 1J grams of carvone and 10 mils of a saturated NaHSOs solution containing .2-3 gram NaHSOs per mil are used for the estimation. The heating is effected as in the first method except that the upper end of the condenser is fitted with a U-tube trap filled with a freshly alka- line solution to restrain any liberated SO2. After cooling, the SO2 is titrated in a suitably diluted aliquot. By this method, an absolutely pure carvone showed 100.3 per cent and a 97 per cent commercial carvone 96.9 per cent. The titration of the NaHSOs is expressed in SO2, and the SO2 con- sumed by the carvone, shown by the difference in titration, goes to form Ci Hi4O(SOsNaH) 2 . Therefore two molecules of SO2 consumed corre- spond to one molecule of carvone present. Camphor, Ci Hi 6 O The dextro camphor, Formosa or Japan camphor, is the official or gum camphor and occurs in the camphor laurel, Cinnamonum camphora (Lauracese), a large tree growing in southern China, Japan, and several adjacent islands. The camphor is found dissolved in a volatile oil, found most abundantly in the roots, but is generally distributed throughout the entire tree. d-Camphor also occurs in small quantities in a number of essential oils such as sassafras leaves, cinnamon root, spike, rosemary, sage, etc. The l-iorm occurs in the oils of feverfew and tansy. Artificial camphor is now prepared to a considerable extent and is a commercial article. When properly prepared and purified it can be distinguished from the natural only by having no optical rotation. By mixing equal parts of d- and ^-camphors obtained from natural sources, a racemic camphor is obtained which is identical in every respect with the synthetic. In making camphor artificially one of the products obtained is pinene hydrochloride. This substance forms a white crystalline mass which ALDEHYDES AND KETONES 609 closely resembles camphor, and has been sold as artificial camphor or turpentine camphor. It is soluble in alcohol but not in water, melts 125° and boils about 208°. It is used as an antiseptic both externally and internally, and among its other uses is recommended for checking the flow of perspiration. The presence of the halogen is readily detected by heating it on a copper wire and noting the green color produced. The structural formula of camphor is as follows, and it forms three classes of derivatives, a, (3 and t, the particular portion of the nucleus effected being indicated. CH 2 — CH CH 2 <-« I C(CH 3 ) 2 <-7r I 0->CH 2 — C CO CH3 Camphor is considered valuable for a number of different disorders and plays an extensive role in medicine. It is a stimulant and sedative according to the dose, also antispasmodic, anaphrodisiac, expectorant, carminative, and diaphoretic. Possessing as it does all these properties, it is combined with a number of other drugs which are dispensed in the form of pills and tablets. The best known preparations containing camphor are of course the official spirit containing 10 per cent of the substance in alcohol, camphor liniment or camphorated oil containing 20 per cent of camphor in olive or cottonseed oils; soap liniment or liquid opodeldoc containing 4-5 per cent camphor; camphorated tincture of opium or paregoric, camphor cerate, and camphor water. Camphor is an ingredient of Warburg Tincture and of inhalants both of oil and glycerin. The common combinations used in pills or tablets include coryza for- mulas where the camphor functionates with quinin, morphin, atropin, and ammonium chloride, sometimes with aconite; Sun cholera mixture, con- sisting of camphor, opium, rhubarb, Capsicum, and peppermint; rhinitis mixture of camphor, quinin, and belladonna; and brown mixture of cam- phor, licorice, opium, benzoic acid, ammonium chloride, tartar emetic, and anise. Other mixtures include those of camphor with opium and Hyoscyamus; with opium and tannic acid; with valerian and Hyoscyamus; with morphin, ipecac, and potassium nitrate; with Podophyllum and ipecac; with salol, opium, bismuth subnitrate, and peppermint, etc. Camphor is often dispensed in ointments intended to allay congestion, rheumatism, and sprains. It will be found with menthol and boric acid; quinin, turpentine, phenol, and opium; with mustard oil and aromatic balsams, etc. 610 ORGANIC SUBSTANCES As ordinarily encountered camphor occurs in blocks or masses which are white and translucent, or in small crystals called " flowers of camphor." The odor is characteristic and the taste pungent and aromatic. Camphor melts at 175° C, boils 204° C, and is inflammable, burning with a luminous smoky flame, (a) #=±44.22° in 20 per cent alcoholic solution. It is very sparingly soluble in water, but goes into solution in all the organic solvents, and in fixed and volatile oils. When triturated with menthol, thymol, phenol, or chloral hydrate liquefaction takes place. When thrown on the surface of clean water it goes through a rapid whirling motion which is arrested by the addition of a very small quantity of oil. On exposure to the air it is slowly volatile, and when moderately heated sublimes without leaving a residue. Camphor does not combine with bisulphites, but it does form a well- defined oxime melting 118-119°, and a semicarbazone melting 236-238°. To prepare camphor oxime a gram or its proportional amount of the sub- stance is dissolved in 15 mils alcohol, treated with an equivalent amount of an aqueous solution of hydroxylamine hydrochloride 1-1 and 1.5 grams sodium hydroxide, and warmed under a reflux for an hour or two. It is well to allow the mixture to stand for about twelve hours after this treatment, and on adding considerable water and enough acetic acid to neutralize the alkali, the oxime will be precipitated. It can be crys- tallized out of hot dilute alcohol. The semicarbazone of camphor may be prepared by dissolving one gram of semicarbazide hydrochloride and 1.23 grams sodium acetate anhydrous in the smallest amount of water possible, and adding the mix- ture to one gram of camphor in absolute alcohol. After warming the solu- tion, it is stoppered and allowed to stand overnight, and the semicarba- zone is then precipitated by water and recrystallized from alcohol. Upon reduction camphor is converted into borneol, and on oxidation to camphoric acid and further to tribasic camphoronic acid. Camphor will absorb gaseous hydrogen chloride, nitrogen peroxide, and sulphur dioxide, forming liquids from which the gases are liberated on the addition of water. The sulphur dioxide compound is used as a disinfectant. The odor of camphor is generally a sufficient indication of its presence in a medicinal preparation. There will seldom if ever be any instances where other things will mask the camphor odor, though camphor may often mask the odor of other ingredients, especially menthol. The only substances which might be confused with camphor from the point of view of odor are pinene hydrochloride, monobromated camphor, and chloretone. If it is necessary to go further with the identity, the camphor can be conveniently converted to the oxime and its melting-point determined. ALDEHYDES AND KETONES 611 The oxime has a peculiar odor suggestive of camphor, but more intense and less pleasing. Much work has been done on the estimation of camphor and very little of it is of any value to the drug analyst. The extensive use of camphor in medicine and the fact that the Pharma- copoeia includes preparations which must contain definite quantities of camphor make it imperative that there should be a reliable method of assay. There have been in vogue for some time procedures depending on the rotation of an alcoholic, benzol, or oil solution and on the loss by evaporation, but they are open to objection, and in certain instances the results might easily be misinterpreted. Artificial camphor is without rota- tory power, natural camphor might contain a portion of the lsevo body, the rotation varies with the strength of the solvent, and fixed oils them- selves on heating often undergo loss or gain in weight. These are a few of the reasons which call for a method based on a more substantial foun- dation. Camphor, being of ketonic character, f onns with hydroxylamine a well defined oxime, C10H16NOH, and advantage has been taken of this property in assaying camphor preparations, the procedure being based on Walther's 1 carvone estimation. The procedure is simple and may be applied directly to spirit of camphor. Of the sample 25 mils are measured into an Erlen- meyer flask of 100 mils capacity, 2 grams of sodium bicarbonate are added, and then, accurately, from a burette, 35 mils of a hydroxylamin solu- tion (20 grams NH 2 OH-HC1+30 mils H 2 0-}-135 mils absolute alcohol aldehyde free). The flask is connected with a reflux condenser, and heated to gentle boiling for two hours; it is then cooled to 25° C, treated with a mixture of 6 mils hydrochloric acid (1.12 specific gravity +6 mils water) transferred to a 500-mil volumetric flask, rinsing out the condenser and flask with water, and finally made up to volume; 50-mil portions are filtered off and titrated as follows : Methyl orange is added and the mineral acid neutralized with normal alkali, then phenolphthalein is added and the hydroxylamine hydrochloride titrated with N/10 alkali. A blank must be run, using the same amount of hydroxylamine solution and 25 mils of alcohol to correspond with the spirits of camphor, the difference in titrations representing the hydroxylamine converted into camphor oxime. Each mil of tenth-normal sodium hydroxide is equivalent to .01509 gram of camphor. The writer has sometimes obtained good results with this method and again has obtained figures which were difficult to explain. The same report comes from other workers. It may be stated, however, that with a pure camphor carefully freed from water and all impurities it is possible to get results which render the method available in analytical work. It 1 Pharm. Centralhalle, 1900, 41 : 613. 612 ORGANIC SUBSTANCES is probable that in case where peculiar results were obtained the fault was due to the grade of camphor employed, or to the personal equation of the worker. Oxaphor Oxaphor is a 50 per cent solution of oxy camphor. C 8 H CHOH / = CioHi602, 8-Q-14 CO a derivative of camphor in which a hydrogen atom has been replaced by a hydroxy 1 group. It is a white crystalline powder, neutral in reaction, melting at 203 to 205° C. It is soluble in about 50 parts of cold water, more soluble in warm water, and readily soluble in all organic solvents except petroleum benzin, in which it is soluble, but from which it crystallizes in feathery aggregations. On prolonged keeping it is prone to undergo decompo- sition, but it keeps permanently in alcoholic solution. It volatilizes gradu- ally at ordinary temperature and readily with steam. Oxycamphor, being decomposed on prolonged exposure to the air, is marketed only in the form of the 50 per cent alcoholic solution under the name of " oxaphor." It is used as a substitute for morphin in respiratory disorders. Camphoric Acid When camphor is treated with nitric acid 1.37 specific gravity, it is converted to camphoric acid, Ci Hi 6 O4, and on further boiling camphor- onic acid, C9H14O6, results with a very small quantity of isocamphoronic acid. Camphoric acid is dibasic and has the accompanying formula ch 2 — ch— cook I C(CH 3 ) 2 CH 2 — C COOH I CH 3 ALDEHYDES AND KETONES 613 while camphoronic is tribasic COOHCOOH I C(CH 3 ) 2 i CH 2 — C— COOH CH3 a stronger chain compound and isocamphoronic is CH 2 : — CH CH2 I I' C(CH 3 ) 2 COOH I COOHCOOH Camphoric acid is odorless, melts 186°, and at a higher temperature is converted to the anhydride. It is somewhat soluble in water, readily in the organic solvents and oils. It is dextrorotatory (a)z>H-46 , but a lsevo form can be obtained from ^-camphor and the combination of the two produces the racemic acid, melting 204°. When heated alone or boiled with acetic anhydride, it yields the anhydride which crystallizes from alcohol, melting 217°. Camphoric acid is an astringent and antiseptic and is used externally in skin diseases, as a gargle alone or mixed with other substances, and for diarrhea, pneumonia, pulmonary affections, calculi, and diseases of the urinary tract. There are many derivatives of this acid which have been offered as possessing certain medicinal properties not obtainable with the parent substance. Phenyl hydrogen camphorate, melting 100° Thymyl hydrogen camphorate, melting 89° Guiacyl hydrogen camphorate, melting 112° Diguiacyl camphorate, melting 124° Eugenyl hydrogen camphorate, melting 115-116° Naphthyl hydrogen camphorate, melting 121-122° Monobromated Camphor, Ci Hi 5 BrO This substance is an a-derivative and is a-Bromocamphor CHBr A CsHi4 \l C ■> CO ft) c i* * r % °S~ 614 ORGANIC SUBSTANCES It forms colorless, prismatic needles or scales, having a mild camphor- aceous odor. It melts 76°, boils 274° without decomposition, sublimes readily and is volatile with steam. It is insoluble in water but dissolves in the organic solvents and oils and in concentrated sulphuric acid from which it separates unchanged on adding water. It is dextrorotatory (a)i>+139 in saturated alcoholic solution. It is decomposed on boiling with silver nitrate solution. On reduction with sodium amalgam in alcoholic solution it yields camphor. Monobromated camphor will often be found mixed with acetanilid and caffeine, and sometimes with the addition of salicylates, Hyoscyamus and Gelsemium. Estimation of Monobromated Camphor in Tablets. — W. O. Emery. — Ascertain the weight of twenty or more tablets, reduce to a fine powder, and keep in a small tube or specimen bottle provided with a tightly fitting cork or glass stopper. Weigh out on a metal or glass scoop an amount of the sample equivalent to not less than 100 nor more than 200 mg. of the camphor derivative alleged to be present. Transfer quantitatively to a small (100 mil) round-bottomed flask, with 20 mils of 96 per cent alcohol and 10 mils of water, containing 15 grams of 1 per cent sodium amalgam. Connect flask by means of a rubber stopper with a short vertical reflux, perferably of the Allin or of the worm type. Heat the mixture over a wire gauze just sufficient to cause the liquid to boil gently for a period of not less than thirty minutes. After cooling slightly, wash out the condenser tube, first with 5 mils of alcohol, then 5 mils of water, receiving the washings in the flask below. Remove latter .to the steam- bath, heating thereon another hour, or until the evolution of hydrogen has nearly or quite ceased. Toward the latter part of this operation, render the liquid about neutral with a few drops of acetic acid in order to further reduction. Transfer the contents of flask to a separatory funnel preferably of the Squibb type, withdrawing and washing the mercury in a second separatory funnel with at least two 50-mil portions of water. Pass the several aqueous solutions quantitatively through a small filter, collect- ing the clear filtrate in a suitable beaker. Precipitate with silver nitrate after the addition of about 5 mils of nitric acid, and proceed with the determination of the resulting silver bromide in the usual gravimetric way, employing if available a Gooch crucible in the operation of filtering The weight of the silver bromide multiplied by the factor 1.23 will give the quantity of monobromated camphor originally present in the sample taken for analysis. A control on the amalgam should be run in order to deter- mine whether any correction is necessary with respect to the presence of halogen in material quantity. This procedure can be used when monobromated camphor occurs alone or in combination with caffein and antipyretics. ALDEHYDES AND KETONES 615 Fenchone, Ci Hi 6 O Fenchone bears a close resemblance to camphor in odor and general properties, but it is a liquid. The d-form occurs in fennel and the Z-form in thuja oils. It melts" 5-6°, specific gravity .943-.946, forms an oxime melting 164-165°, but does not react with bisulphite or phenylhydrazine. Thujone, Ci Hi 6 O Thujone or tanacetone is a constituent of the oils of thuja, tansy, sage, wormwood, and other species of Artemisia. It has a characteristic odor to which the oils owe in part their aroma, which odor serves a ready means for its identification. Pure thujone is a colorless, oily liquid, boiling 84.5° at 13 mm., specific gravity .9126 to .916 at 20°, and rotation +68°. It forms a bisulphite compound, an oxime melting 54-55°, and a semicarbazone melting 171— 172°. As thujone is a normal constituent of oil of wormwood its presence would naturally be expected in the beverage known as absinthe, but in neither of the white nor green varieties, as sold in this country previous to the embargo, was the writer able to detect the slightest trace. Tansy oil is used in female pills, and wormwood oil is an ingredient of a certain type of antiseptic liniment combining the virtues of a number of essential oils in menstruum of acetone or alcohol. Thuja oil, from Thuja occidentalis, the Arbor Vitse or White cedar, is used as a tonic and emmenagogue, and as an antiseptic in skin diseases. Pulegone CK 3 CHa v t! c / \ H 2 C CO I I H2C CH2 !H— CH3 ^ Pulegone is the chief constituent of the oil of Mentha pulegium, Euro- pean pennyroyal, and occurs also to a considerable extent in the oil of Hedeoma pulegioides. These oils, though from botanically different species, are similar in composition and are probably used indiscriminately as " pennyroyal oil " in medicinal products. 616 ORGANIC SUBSTANCES Pulegone is a colorless liquid with a sweet peppermint-like odor, boiling 130-131° at 60 mm., specific gravity .9323 at 20° C, rotation +22.89°. Its oxime melts 118-119°, and its semicarbazone at 170°. It forms a bisulphite compound. When heated with water to 250° under pressure, it yields acetone and methyl hexanone, and on oxidation with potassium permanganate acetone and beta-methyl adipinic acid. Menthone, Ci Hi 8 O Z-menthone occurs in peppermint oil. It is a colorless liquid with a menthol-like odor, boiling 207°, specific gravity .8960 at 20°, rotation -28.18°, oxime melting 59° and semicarbazone melting 184°. It does not unite with bisulphite. THE CARBOHYDRATES The carbohydrates are properly considered at this point, as they possess either the properties of ketone alcohols or aldehyde alcohols. They embrace the very important group of substances known as the sugars which are much more interesting to the food than to the drug chemist. The latter, however, will often meet with sugars, as they make up the bulk of some of the most important classes of galencial preparations, including pills, tablets, elixirs, syrups, and powders, and their determi- nation will often be necessary in arriving at the ultimate composition of a sample under investigation. Cane sugar or sucrose is of common occurrence in all of the above- mentioned classes; commercial glucose which is made up in large part of dextrin and maltose, is used as a builder in pill masses; milk sugar or lactose is present in tablet triturates and in powders as a diluent; maltose will be found in malt extracts; and a mixture of several different carbo- hydrates is usually found in the many different infant foods. The carbohydrates with aldehyde or ketone groups form osazones with phenylhydrazine, and these bodies are of value in arriving at the identity of a sugar. It is inadvisable, however, to place too great a depend- ence on these compounds, because the melting-points are in some instances fairly close to each other, and it is often a question whether one is dealing with an impure osazone of an individual, or the mixed osazones of two different sugars. For a detailed account of the chemistry of the carbohydrates one should refer to the special books on the subject; but as a guide to the workers the accompanying table has been compiled, and in it will be found a brief summary of the principal distinguishing properties of these sub- stances. ALDEHYDES AND KETONES 617 Common Name Formula Products of Hydrolysis Specific Rotation Osazone Dextrose ...... Grape Sugar or Glucose CH>OH(CHOH) 4 CHO +52.80 Melts 204-5° Levulose Fruit sugar or Fructose CH 2 OH(CHOH) 3 COCH 2 OH —90.2° Melts 204° Sorbose CeHisOs —42° Melts 164° Galactose CH 2 OH(CHOH) 4 CHO +81° Melts 196 Arabinose +105° Melts 160° Sucrose Cane sugar or Saccharose Cr^H^Ou Dextrose and levulose +66.50 Xon-reducing Trehalose Occurs in Manna Dextrose +197° Xon-reducing Lactose Milk sugar Cr.H-Oii Dextrose and Galactose +52.50 Maltose C, 2 H-Oii 2 molecules of Dextrose + 138° Starch (CoHioOo)?! Acid hydrolysis gives Dextrin and then dex- trose Diastase gives Dextrin and Maltose Dextrin (CYELoOo),, Cellulose (C6HloOo)fl CosHesOai Levulose —39.5 The accompanying method for detecting the nature of the carbohy- drates present in mixtures is included. Identification of Carbohydrates. — (A) To 5 mils of a weak solution of the substance add a few drops of 15 per cent alcohol solution of a-naph- thol; float this over cone, sulphuric acid, a violet or blue zone at the line of contact indicates a carbohydrate. If the substance is insoluble in water dissolve in 25 per cent sulphuric acid and float over this solution a mixture of water and a-naphthol and observe as above. (B) Shake one gram of the substance with 10 mils water. Decant or filter from any insoluble residue which may be Starch or Cellulose. Save nitrate. To insoluble matter in (^not on filter paper) add few drops dilute aqueous solution of iodin, blue color shows starch. Filtrate divide into 3 portions a, /3, and y. a. Divide into 2 portions 1 and 2. To 1 add an equal volume of 94 per cent alcohol; a precipitate indicates Dextrin. To 2 on a white slab add a few drops of dilute solution of iodin; blue color indicates cooked starch; reddish-brown indicates Dextrin. 0. Boil with Burford's solution of copper acetate; precipitate of CU2O indicates either Dextrose or Levulose or both. Filter and treat 618 ORGANIC SUBSTANCES filtrate as follows: Add excess of basic lead acetate solution; filter and to filtrate, add sodium sulphate solution in excess and filter from lead sulphate. To filtrate, which must still be blue (if not add a few drops of copper sulphate solution) add sodium hydroxide to make alkaline and heat to boiling; a red precipitate of CU2O indicates Maltose or Lactose or both. Filter. To filtrate add a few drops sulphuric acid and boil, neutralize with excess sodium hydroxide, add a few drops copper sulphate and heat to boiling; a red precipitate of CU2O indicates Saccharose (Cane Sugar) . 7. To determine whether Maltose or Lactose are present. Add ammonia in excess, add a few drops of alkaline bismuth solution and set the tube in water at a temperature of about 60° C. Maltose solution reduces the bismuth, while Lactose does not at this temperature within one-half hour. To detect Lactose. To about 5 mils of strong nitric acid; add .5 gram original substance and warm gently until red fumes begin to come off. Set tube in about 200 mils hot water and allow it to remain there until cold ; in a few hours white crystalline mucic acid separates if lactose is present. Hediosit Hediosit, C7H12O7, is the lactone or inner anhydride, of alpha-gluco- heptonic acid, CH 2 OH • (CHOH) 5 COOH. It is a white, crystalline, odorless powder, with a sweet taste. It is readily soluble in water, slightly soluble in alcohol, and almost insoluble in ether. The aqueous solution is acid toward litmus and does not reduce in Fehling's solution. If 1 gram of hediosit is heated on a boiling-water bath with 1 mil of water and .5 gram of phenylhydrazine, and a few mils of absolute alcohol added, a fight-colored crystalline mass will form, which after recrystallization from dilute alcohol melts at 172° C. If 1 gram to 2 grams of hediosit weighed into a flask are dissolved in 10 to 20 mils of water by warming and a few drops of phenolphthalein solution added, 9.1 to 9.6 mils of half -normal sodium hydroxide per gram of hediosit taken should be required to neutralize the solution. If 9 grams of hediosit is dissolved in water to make 100 mils and allowed to stand at the ordinary temperature for twenty-four hours the solution, when polarized at 17° C, should show a specific rotation of about -52° for the sodium fine. After neutralization with caustic soda the solution has a slight dextrorotation. Hediosit is used as a sweetener of the food of diabetic patients. ALDEHYDES AND KETONES 619 ANALYSIS OF INFANT FOODS These products consist usually of carbohydrates and milk solids in varying proportions. They often contain sucrose and sometimes dextrose, but the carbohydrates, which are present in almost all cases are dextrin, maltose, and lactose. As sold on the market these foods are usually in the form of dry powders, and the analysis in so far as the determination of the content of nitrogen, ash, fat, and moisture are concerned, is the same as for any food product. For fat, the Rose-Gottlieb method is preferable to any other. Assay for Carbohydrates. — The method of estimating the individual carbohydrates in infant foods was worked out in my laboratory by Mr. T. M. Rector during the course of an extended research which we made on these products. In preparations containing mixtures of sucrose, maltose, lactose, and dextrin, the sucrose is determined by loss of rotation after inversion with invertase. The dextrin is determined by loss of polarization after pre- cipitation with lead acetate and ammonia. The combined polarization of the sucrose and dextrin is subtracted from the total polarization, giving the polarization of the maltose and lactose. A copper reduction is then run on an aliquot of the solution and the amount of copper reduced by 1 gram of the sample is calculated. From this value and the combined polarization of the maltose and lactose the percentages of these sugars are calculated by a formula. No claims are made for the availability of this method beyond mix- ture of carbohydrates of the malted milk type or those prepared syn- thetically from the same ingredients. Furthermore, the conversion of starch to maltose and dextrin in the preparation of these foods is probably incomplete, and the mixture unquestionably contains dextrin-like sub- stances in various stages of conversion. For this reason the results obtained for dextrin must of necessity be only approximate, and while with known mixtures of the pure ingredients the determination yields theoretical results, in commercial articles the figures obtained would require slight modifications to obtain these actual values. The specific rotary power of maltose is 138, while the same value. for lactose is only 52.5. On the other hand, lactose has a greater reducing power on Fehling's solution than its isomer. Either of these values would serve as a basis to determine the sugars if the total sugar was known, but in the absence of that data a formula, based in the ratios between the polarization and copper-reducing power of the sugars, was devised to determine the ratio of the quantity of one sugar to the other. Then, from the polarization due to the two sugars, their percentages in the mix- ture was calculated. 620 ORGANIC SUBSTANCES To get the best result the constants of the difference carbohydrates should be determined by the analyst himself in order to obviate personal errors as well as possible errors in his polariscope. The constants used are set forth in the following table : Carbohydrates Polarization (Ventzke) Cu.O per gram Maltose Lactose 207.5 79 79.2 100 300 1.277 1.556 2.232 Dextrose Sucrose *Dextrin * The value used for dextrin was the figure given in the text books. Of several commercial samples of declared purity, none ran over 250°. The copper-reduction figures were arrived at by using a quantity of sugar that would give about 225 mg. of CU2O in a reducing sugar deter- mination conducted according to the method of Munson and Walker. The analytical procedure follows: Weigh out 32.5 grams -of the sample and transfer dry to a 250-mil. graduated flask by means of a wide-stemmed funnel. Add 150 mils of water and digest for at least two hours, shaking frequently. Then add 10 mils each basic lead acetate and alumina cream, shaking flask after each addition, and make up to the mark with water. Filter into a flask through a ribbed filter, keeping the funnel covered with a watch-glass. Add sufficient crystals of normal potassium oxalate to remove excess of lead, allow precipitate to settle and filter through a dry double filter, being sure to guard against loss by evaporation. Preserve 25-50 mils of this solution overnight, to destroy birotation, and polarize in a 200-mm. tube. Multiply reading by 2 and denote product by a. Transfer 50 mils of the solution to a 100-mil volumetric flask, add invertase and keep at from 25-30° C. overnight, in an incubator if neces- sary. Add 5 mils alumina cream, make up to mark, mix, filter, and polar- ize in a 200-mm. tube. Multiply reading by 4 and denote product by b. To another aliquot of the original solution of 50 mils contained in a 100-mil volumetric flask, add 25 mils of a 10 per cent solution of lead acetate and 10 mils of strong ammonia. Make up to volume, shake and allow precipitate to settle. Filter through a ribbed filter with the proper precaution to prevent evaporation, and polarize solution immediately in a 200-mm. tube. Multiply reading by 4 and denote product by c. Make up 25 mils of the original solution to 250 mils and run a copper reduction on 25 mils of this solution according to the method of Munson and Walker. Divide the weight of the reduced CU2O by .325, the amount of sample represented by the aliquot taken, and denote quotient by d. ALDEHYDES AND KETONES 621 In most malted milks and similar products this amount will reduce between 200 and 250 mg. of CU2O. If the weight is outside these limits, the amount of solution should be adjusted to bring the value within their bounds. CALCULATIONS OF CARBOHYDRATES Dextrin P=the polarization of 26 grams pure dextrin in 200 mm. tube at 20°C. = 300. Then o = per cent dextrin in sample. Sucrose Sucrose is calculated from Clerget's formula, which in this case is: 100 (a -b) 142.66 -~ = per cent of sucrose in sample = s Maltose and Lactose P= polarization of 26 grams of pure maltrose in 200-mm. tube at 20° G. = 207.5. P f = polarization of 26 grams of pure lactose under these same con- ditions =79. R = grams of CU2O reduced by 1 gram of maltose under conditions of method. R f = grams of CU2O reduced by 1 gram of lactose under same con- ditions. x — parts of maltose in 100 parts of reducing sugar. 100 —x = parts of lactose in 100 parts of reducing sugar. 7 7 =per cent of total reducing sugar. *S = per cent of sucrose in sample. ml _ c-s Px+(100 -x) P' inen d £x+(100 - x)R' 100 (c -s) = T Px+P'(10Q-x) Tx = = per cent maltose. r(ioo -x)- = per cent lactose. If sucrose is absent, this formula is simplified, the first number becom- ing c/d. By its use any two dextrorotary sugars may be determined, without knowing the total sugars, by substituting the prooer values for their polarization and copper reduction. 622 ORGANIC SUBSTANCES In the appended table the analyses of some commercial brands of infants foods are shown. A and B are samples of malted milks put out by different firms. The others would be recognized as much advertised infant foods if their names were given. Sample a b c d Dextrin Maltose Lactose Sucrose Dextrose Per Cent Per Cent Per Cent Per Cent A 126.4 89.6 .691 12.3 38.3 12.1 B 126.4 88. .694 12.8 37.1 14.1 C 87.4 58.4 54 .322 11.1 11.1 11.6 21.86 D 149 117.8 .786 10.4 55.5 2.5 E 43.2 28.4 .739 4.9 4.2 29.5 Samples A, B, and C contain considerable milk solids, having from 6 to 10 per cent of butter fat besides the milk sugar and casein. Sample C appeared to be a malted milk with cane sugar added. Sample E con- tained a large amount of unconverted starch besides the soluble carbo- hydrates. With the exception of sample E, none of these products gave a blue reaction with iodin. It is probable that the starch was converted entirely to dextrins, and that the dextrins present has a Ventzke value nearer 250 than 300. If this were so, the dextrin value would range higher in the sample than the figures indicate. The results obtained by this method on mixtures of various sugars are consistent enough for all practical purposes, but as a malt prepara- tion of known composition is impossible to obtain, we have no way of finding out how close the results run on commercial preparations. The presence of traces of other sugars may in some cases cause the figures to vary slightly from the true amounts, but the results agree very well with what one would expect in such preparations from a general knowledge of their composition. The results are certainly of more practical use than a meaningless collection of polarization and copper-reduction figures, Cellulose Method for Determination of Crude Fiber.— Extract a quantity of the substance representing about 2 grams of the dried material with ether, using any suitable form of extraction apparatus. To this residue in a 500-mil flask add 200 mils of boiling 1.25 per cent solution of sul- phuric acid; connect the flask with an inverted condenser, heat at once, boiling gently for thirty minutes Filter through silk, and wash with ALDEHYDES AND KETONES 623 hot water until free of acid. Rinse the residue back into the same flask with 200 mils of boiling 1.25 solution of sodium hydroxide, boil at once, and continue the boiling in the same manner as described above for the treatment with acid. Filter through silk and wash with boiling water until the washings are neutral. The residue is then transferred on to a weighed Gooch. This is best accomplished by spreading the silk filter (which is about 18 cm. in diameter, cut and folded like an ordinary filter paper) on a watch-glass slightly larger than the silk filter. The residue is then gently scraped on the weighed Gooch by means of a small spatula. The remaining portion is then rinsed with water, using as little as possible to avoid clogging, suction is then applied, and finally washed with alcohol and ether. Dry to constant weight at 110°; and weigh, after which incinerate completely. The loss in weight is considered crude fiber. The solution of sulphuric acid and sodium hydroxide are to be made up of the specified strength determined accurately by titration and not merely specific gravity. CHAPTER XVII ORGANIC ACIDS ALIPHATIC SERIES The organic acids are encountered to a considerable extent in medi- cinal chemistry. In the aliphatic series we find the monocarboxylic acids of the formic and acetic group of the homologous series C„H2 n +iCOOH, the oxidation products of the glycols which are hydroxy carboxylic or poly- carboxylic, and unsaturated acids of both kinds. The fatty acids of the general formula C«H2n+iCOOH may be regarded as derivatives of the paraffins, alcohols, or aldehydes. HCH3-HCH2OH -HCHO -HCOOH - The grouping -Of is known as the carboxyl and is characteristic X)H of them all. At ordinary temperatures, the lower members of the series are color- less liquids except acetic acid, which solidifies at 16-17°, and are miscible with water, alcohol, and ether in all portions. As the molecular weight increases they become oily in character. The pungency disappears and they are less readily soluble in water. The higher members are waxy or unctuous solids, with a faint odor and insoluble in water. They are all volatile with steam except the higher members, which, however, may be distilled in superheated steam. The specific gravity decreases and the boiling- and melting-points increase as the series is ascended. It should be noted, however, that acids with an odd member of carbon atom melt at a lower temperature than the preceding members containing an even member. These acids are quite stable and are only oxidized with difficulty. The lower members decompose carbonates, dissolve metals and metallic hydrox- ides, but these acid properties soon disappear and the higher members are with difficulty recognized as acids by the ordinary tests. The metallic salts of the lower members are soluble in water, but on passing up the series the solubility decreases, and in the case of the higher acids only the alkali salts are soluble. Many of the salts of the higher acids are soluble in ether. The fatty acids react with alcohols, especially in the presence 624 ORGANIC ACIDS 625 of dehydrating agents, forming ethereal salts and water. When treated . with phosphorus pentachloride they yield acid chlorides, which interact with hydroxy compounds to produce ethereal salts, with ammonia to give amides, and on distillation with an alkali salt of a fatty acid to pro- duce anhydrides. C 2 H5COOH+PCl5 = C2H 5 COCl+POCl3+HCl C2H 5 COCl+CH 3 OH=C 2 H 5 COOCH3+HCl C2H5COCI+NH3 = CH3CONH2+HCI C 2 H5COCl+C2H5COOH = (C2H 5 CO)20+KCl The organic acids and their derivatives will be encountered in a large percentage of the mixtures analyzed by the chemist in this line of work. Often they are subsidiary products to which no attention need be paid, again the crucial feature of an analyis will depend upon their accurate identification and determination, either as a measure of some parent product of which they are a part, or as a measure of their therapeutic efficiency, and still again their influence as contaminating features in the determination of other substances must be considered. In the aliphatic series the acids which are used for their medicinal properties include formic, valerianic, agaricic, citric, tartaric, lactic, angelic, and succinic, and to a lesser extent acetic, oleic, and stearic. In the aromatic series benzoic, salicylic, and phenolsulphonic acids and their derivatives make up an appalling list of medicinal agents. Allusion has already been made to the influence of volatile acids on alcohol determinations. The identification of some of the acids will often give valuable evidence as to the presence of certain drugs; angelic acid will indicate angelica root, valerianic acid may denote that valerian has been employed, and benzoic and cinnamic acids often will lead to the discovery of the aromatic balsams. Again the presence of aliphatic acids furnishes additional evidence regarding the use of specific drugs in complex mixtures, for instance the simultaneous discoveiy of the Sanguinaria alkaloids, and a relatively large amount of acetic acid will indicate that fluid extract of Sanguinaria was one of the components of the mixture. The acids play an extremely important part in the identification of fats and oils, and in mixtures where the ordinary constants of the oils have become modified or rendered doubtful, the separation of the fatty acids is the only means of identifying the original product. Sometimes it will be necessary to convert the mixed acids into volatile esters, fraction- ate the mixture and then reform the acids. By this means more has been 626 ORGANIC SUBSTANCES accomplished in clearing up the chemistry of cod-liver oil than by any other method. One general observation regarding the work of the analytical chemist in detecting organic acids may not be amiss at this point. In identifying the acids by color and precipitation tests it is always advisable to convert the suspected individual into a neutral stable salt and to work with an aqueous solution of the latter. For instance, it is stated that benzoic acid will give a flesh-colored precipitate with ferric chloride, but the analyst will usually be disappointed if he attempts to get this reaction by adding ferric chloride to a residue or an aqueous solution of the free acid. But if he adds sufficient dilute ammonia to dissolve the free acid and then evaporates the excess, the aqueous solution will give a copious precipitate of the characteristic salt. Formic Acid, H'COOH Formic acid is a colorless, hygroscopic liquid at ordinary temperatures, Specific gravity 1.241 at 0° C, it melts at 8° and boils at 101°. It has a pungent, irritating odor, is very caustic, blistering the skin, and is mis- cible with alcohol, water, ether, and glycerin. It is acid to litmus, decom- poses carbonates, and forms well-defined salts. In some of its reactions it resembles the aldehydes, it reduces ammoniacal silver oxide with evolu- tion of carbon dioxide. When mixed with concentrated sulphuric acid it is rapidly decomposed into carbon monoxide and water, this reaction distinguishing it sharply from the other acids of the aliphatic series. All metallic formates have the same property. Formic acid and formates reduce mercuric chloride to mercurous chloride, and this property is available for their determination. On adding magnesium ribbon to formic acid, hydrogen is evolved and the acid is reduced to formaldehyde, which can be recognized by the morphin sulphuric acid reaction. Formic acid can be removed completely from an aqueous solution by distillation, but like hydrochloric acid it forms a definite hydrate which has a definite distillation point, and can never be completely separated from water by distillation. As ordinarily used it will be found in 25 per cent solution and the acid content can be determined by direct titration with normal acid. Formic acid is the essential ingredient of the treatment for rheumatism known as the " bee sting " remedy. It is also used as an antiseptic, diuretic, and tonic, but it is too irritating for general use. Sodium formate is employed for the purposes above mentioned, and also hypodermically in surgical tuberculosis. It is sometimes dispensed with Adonis vernalis (false hellebore) for pneumonia. The metallic formates are all soluble in water, but the lead and silver ORGANIC ACIDS 627 salts are only moderately soluble; they are all decomposed by warm concentrated sulphuric acid with evolution of carbon monoxide, and by dilute acids yielding formic acid. The alkali formates are deliquescent and when heated to 250° they are converted to oxalates with evolution of hydrogen. When ammonium formate is strongly heated, it is first converted into formamide and then to hydrogen cyanide. HCOONH4 = H '• CONH2+H2O HCONH 2 = HCN+H 2 Silver formate is precipitated in colorless crystals on adding silver nitrate to a concentrated solution of alkali formate, but it is unstable and darkens quickly. The detection of formic acid or a formate is accomplished by adding a slight excess of phosphoric acid to the suspected sample and distilling with steam, the distillate being collected in a receiver containing water and barium carbonate. The distillate is then evaporated to drive off any volatile constituents, aldehydes, etc., diluted with water and filtered. Portions of the filtrate are then tested with ammoniacal silver oxide and mercuric chloride for the characteristic reductions, and another portion evaporated to dryness in a test-tube and warmed very gently with con- centrated sulphuric acid and the escaping gas tested with a flame; carbon monoxide will ignite and burn at the mouth of the tube. The detection and determination of formates will sometimes be of moment in the identification of chloral. For the determination of formic acid in fruit juices Seeker has modified Finkes method slightly. The results obtained are accurate and the pro- cedure can be used with medicinal products. In the case of free formic acid this method can be used without modi- fication, but if the qualitative examination indicated a formate, phosphoric acid should be substituted for tartaric. The apparatus required consists of a steam generator S, a 300-mil flask A in which the sample is placed, a 500-mil flask B, con- taining a suspension of barium carbonate, a spray trap T, a condenser, and a 1-liter graduated flask C. The tip of the tube D, leading into B, consists of a bulb containing a number of small holes to break the vapor into small bubbles. For thin liquids like fruit juices, use 50 mils. For heavy liquids and semi-solids like sirups and jams, use 50 grams diluted with 50 mils of water. Place the sample in the flask A, add 1 gram of tartaric acid, and connect as shown, the flask B having been charged previously with a suspension of 2 grams of barium carbonate in 100 mils of water. If much acetic acid is present, sufficient barium carbonate must be used 628 ORGANIC SUBSTANCES so that at least 1 gram remains at the end of the operation. Heat the contents of flasks A and B to boiling and distill with steam from the gener- ator S, the vapor passing first through the sample in flask A, then through the boiling suspension of barium carbonate in B, after which it is con- densed, and measured in the graduated flask C. Continue the distillation until 1 liter of distillate is collected, maintaining the volume of the liquids in the flasks A and B as nearly constant as possible by heating with small Bunsen flames, and avoiding charring of the sample in the flask A. After 1 liter of distillate has been collected, disconnect the apparatus and filter the contents of flask B while hot, washing the barium carbonate with a little hot water. The filtrate and washings should now measure about 150 mils. If not they should be boiled down to that volume. Then add 10 mils of the sodium acetate, 2 mils of 10 per cent hydrochloric acid, and 25 mils of the mercuric chloride reagent. Mix thoroughly and immerse the container in boiling water-bath or steam-bath for two hours. Then filter on a tared Gooch, wash the precipitate thoroughly with cold water and finally with a little alcohol. Dry in a boiling water oven for thirty minutes, cool, weigh, and calculate the weight of formic acid present by multiplying the weight of the precipitate by .0975. If the weight of mercurous chloride obtained exceeds 1.5 grams, the determination must be repeated, using more mercuric chloride reagent or a smaller amount of sample. A blank test should be conducted with each new lot of reagents employed in the reduction, using 150 mils of water, 1 mil of 10 per cent barium chloride solution, 2 mils 10 per cent hydrochloric acid, 10 mils of the sodium acetate, and 25 mils of the mercuric chloride reagent, heating the mixture in a boiling water-bath or steam-bath for two hours. The weight of mercurous ORGANIC ACIDS 629 chloride obtained in this blank test must be deducted from that obtained in the regular determination. Acetic Acid, CH 3 COOH Acetic acid is the bane of the analyst in determining alcohol in drug mixtures. The writer has found it consistently in almost every alcoholic distillate, and as nobody has ever investigated the extent of its influence on the specific gravity, it has to be eliminated before an accurate determi- nation of the alcoholic content can be assured. It is probable that in a great many instances its influence is negligible. Besides occurring as an oxidation product of alcohol, acetic acid occurs in drug products to a large extent as a vehicle; as a medicine pure and simple, the chief employment of glacial acetic acid is as a vesicatory and for removing warts and corns. It is sometimes used as a substitute for cantharides where a speedy blister is desired. Acetic acid is employed in the preparation of pharmaceutical products known as vinegars, of which the most important include cantharides, ipecac, opium, squills, Colchicum, Lobelia, Sanguinaria, and the aromatic vinegar consisting of several aromatic oils in alcohol and dilute acetic acid. Acetic acid also occurs in fluid extract of ergot, Nux Vomica, and Sanguinaria. The dilute acid is used as an excitant in syncope, asphyxia, and head- ache, where the vapors are applied to the nostrils. Camphorated acetic acid is an old remedy composed of camphor, alcohol, and dilute acetic acid. It is recommended in fainting and nervous debility. Pure, anhydrous acetic acid is a crystalline solid, melting 16 • 5°, boiling at 118°, with a pungent, penetrating odor and a burning action on the skin. It is inflammable when near its boiling-point and burns with a feebly luminous flame. It is hygroscopic, miscible with alcohol, water, and ether, is an excellent solvent for many organic substances, and for certain inorganic elements as sulphur and iodin which do not dissolve in water. It is not removed from its aqueous solution by immiscible sol- vents, and by this means it may be separated from many of the higher acids of the same series, and from the aromatic acids w r ith the exception of phenolsulphonic. It is a fairly strong acid, dissolving certain metals and metallic oxides, but differs from formic acid in possessing no reducing properties and being stable towards sulphuric acid. On neutralizing acetic acid with sodium hydroxide and then warming the solution with a little sulphuric acid and alcohol, ethyl acetate is formed and is readily recognized by its characteristic fruity odor. On adding ferric chloride not in excess to free acetic acid a deep-red color soon appears which does not disappear on boiling nor yield a precipitate. If the acid 630 ORGANIC SUBSTANCES has been neutralized with sodium hydroxide, or the suspected sample is an acetate the same deep-red color is obtained, and on boiling, a heavy deposit of basic ferric acetate results. The red color is destroyed by hydrochloric or sulphuric acids, differing from that given by meconic acid, and it is not soluble in ether as is the case with thiocyanates. Formic acid will give a red color, but it has other well-marked reactions differing entirely from those of acetic acid, and is readily differentiated. Citric and tartaric acids and their salts give only a yellow color with ferric chlo- ride, but with Rochelle salts a red color develops on long standing. Chlorine, bromin, chromic acid, etc., convert formic acid into carbon dioxide, but they do not affect acetic acid in this way. Chromic acid is without action on pure acetic acid. The normal acetates are all well-defined salts. The silver salt is sparingly soluble in water and is precipitated in colorless crystals on adding silver nitrate to a concentrated neutral solution of an acetate. The double salts of copper acetate and arsenite are insoluble and have a wide use as insecticides. Lead acetate is used as an astringent, styptic, and sedative. It is given for diarrhea, dysentery, and internal hemmorhages, in gonorrheal injections, externally as an astringent eye lotion, and as a remedy for poison ivy. It will often be found in conjunction with opium and cam- phor in diarrhea mixtures, and with zinc acetate or sulphate and the Hydrastis alkaloids in astringent washes. An aqueous solution of acetic acid may be tested for the presence of the acid by neutralizing a portion with sodium hydroxide, concentrating and then warming with alcohol and sulphuric acid when the character- istic odor of the ethyl acetate is evolved. It will also respond to the test with ferric chloride. In such simple mixtures the acetic acid may be determined by titration with standard alkali. In complex mixtures the acetic acid should be distilled off into an aqueous suspension of barium carbonate, and the distillate concentrated and then filtered, the filtrate being tested as above. Acetic acid in com- bination as acetate may be detected by distilling the mixture with steam in the presence of phosphoric acid, running the distillate through barium carbonate as described under the determination of formic acid and finally filtering off the solution of barium acetate and testing as above. Assay of Acetates. — The assaying of acetates may be accomplished by distillation in the presence of sulphuric or phosphoric acid. The sample is transferred to a distillation apparatus fitted up for steam distillation, using a spray trap to connect the distillation flask with the condenser. The solution is made up to 100 mils and 5 mils of concentrated sulphuric acid added. Distillation is continued until about 600 mils of liquid have been collected, and the acid residue reduced to about 20 mils. The dis- ORGANIC ACIDS 631 tillate is titrated with N/10 alkali, using phenolphthalein as an indicator, finally boiling the liquid until a faint pink color persists. It is well to add a quantity of distilled water to the acid residue and distill over a fraction of 100 mils to be sure that all of the acetic acid has been expelled. Cor* rect the result by a blank determination. Formic acid can be separated from acetic by forming the lead or mag- nesium salts, concentrating and adding excess of alcohol in which the form- ates are insoluble, while the acetates remain in solution. Acetic acid gives three chlor, three bromo, and three iodo- derivatives, one of which, trichloracetic acid is employed to some extent as medicine and has already been described, see page 593. Acetic anhydride is prepared by heating anhydrous sodium acetate with phosphorus oxy chloride. 4CH 3 COONa+POCl3 = 2(CH 3 CO)20+NaP03+3NaCl It is a mobile liquid boiling at 137°, with an unpleasant irritating odor. It does not mix with water but is soon decomposed, especially on warming, giving two molecules of acetic acid. The Valerianic Acids The Valerianic acids need no other characteristic than their odor to assure the analyst of their presence. This odor is characteristic and is a conclusive test. Its penetrating and clinging properties are familiar to all who have had any experience in drug analysis. Valerianic acid or its esters are present in the roots of valerian, angelica and sumbul and in Viburnum bark, and the isolation of the acid from liquid mixtures containing drug extractive, points to the presence of these drugs. Angelica and sumbul contain in addition angelic acid, which has well-defined and character- istic properties. There are four possible isomerides of the molecular formula C5H10O2, but isovalerianic or isopropylacetic acid (CHs^CHCH^COOH, and active CH 3 valerianic or methyl ethyl acetic acid, yCHCOOH are the most im- C 2 H 5 X portant. The former when pure is a transparent colorless oily liquid, boiling 175°, miscible in all proportions with alcohol, ether, and chloroform and fairly soluble in water from which it may be separated by adding calcium chloride. It is the principal valerianic acid obtained from the drugs and is also prepared from amyl alcohol. It is used in nervous affections, hysteria, and mania. Active valerianic acid is the principal valerianic acid obtained from angelica. It boils 172° (a)o -17.85. 632 ORGANIC SUBSTANCES The valerianates are used to a considerable extent in medicine, especially the salts of iron, zinc, quinin, and strychnin. These salts are employed as sedatives in elixirs and liquid products. They are more or less unstable, and are acid in reaction, and give off a strong odor of the acid. The acid is readily separated on warming with mineral acid and distilling with steam. Isovalerianic acid forms a hydrate, C5H10O2H2O, boiling 165°. Iso- valerianates are decomposed by acetic, tartaric, and citric acids. Zinc valerianate is distinguished from zinc caproate by being soluble in water. Nonylic Acids Pelargonic or normal nonylic acid, CgHiyCOOH, is formed when essential oil of rue is oxidized by nitric acid. It is an oily liquid with a faint odor melting 12°, boiling 245°, insoluble in water. The palargo- nates with the exception of the alkalies are insoluble in water. Myristic Acid Myristic acid, C13H27COOH, melts 54°. It occurs in oil of nutmeg, probably in combination. Palmitic Acid Palmitic acid, C15H31COOH, occurs in palm oil as a gly#eride, as an ethereal salt, cetyl palmitate, in spermaceti, and as myricyl palmitate in beeswax. It is also found combined in other fats and waxes of lesser importance, and in the complex resinous constituents of many drugs. Palmitin, the triglyceride, occurs in the most liquid fats such as palm and cocoanut oil, as well as in butter and human fat. The pure acid is a colorless waxy substance, melting at 62° C, soluble in alcohol and ether, insoluble in water and decomposing on distillation, except in the presence of steam. The alkali palmitates are soluble in water and occur in soap. The salts of the other bases are insoluble in water, and even the alkali salts are thrown out of acid solution on add- ing sodium chloride. Margaric Acid, Ci 6 H 33 COOH The acid is obtained by boiling cetyl cyanide with an alkali. It was formerly supposed to exist as a glyceride in natural fats, but subsequent researches seem to prove that the substance obtained at that time was a mixture of palmitic and stearic acid. It is a crystalline waxy substance, melting 59-60° C. ORGANIC ACIDS 633 Stearic Acid Stearic acid, C17H35COOH, occurs as a glyceride in many animal fats, especially suet, and in the solid fats generally. The pure acid is a white crystalline solid, melting at 69° and resembling palmitic acid in its chem- ical and physical properties. Sodium and potassium stearates are soluble in water to a clear solution, but on adding a large excess of solvent, the acid stearates are deposited in scaly crystals. Dioxystearic, Ci7H33(OH) 2 COOH, melting 35°, is. obtained by treating dibromisoleic acid with silver oxide. Isotrioxystearic, Ci7H32(OH)3COOH, melting 111°, is formed on oxidiz- ing castor oil with alkaline permanganate. Tetraoxystearic or sativic, Ci7H 3 i(OH) 4 COOH, melting 159-161°, is formed on oxidizing linoleic acid with alkaline permanganate. Arachidic Acid, C19H39COOH The acid in the form of a glyceride is one of the important constituents of peanut oil. Its separation and identification is a problem familiar to the food chemist, as its presence is used in drawing conclusions as to the adulteration of other edible oils, especially olive oil. As it occurs as a glyceride in other oils and to some extent in olive, its occurrence is not necessarily a conclusion that peanut oil has been used as an adulterant. The pure acid occurs in small shiny plates of a pearly luster, melting 75° C. Behenic Acid, C 2 iH 43 COOH Behenic acid is found in the oil expressed from the seeds of Moringa oleifera (oil of ben). It melts 80-82° and solidifies 79-76°. It has been prepared synthetically from erucic acid and then melts 83-84°. This acid is of interest as it is used in the preparation of a series of organic arsenic compounds for which medicinal virtures are claimed. The salts of the bromo and iodo derivatives of behenic acid prepared from erucic acid are used as remedies in which it is desired to obtain the effects of bromin or iodin. Sabromin, Dibrombehenate of Calcium, ^iBLuBroCOOH^Ca Sabromin is a colorless, odorless, and tasteless powder claimed to contain about 29 per cent bromin and about 3.8 per cent calcium. It is insoluble in water and alcohol, soluble in ether, acetone, benzol, ligroin and tetrachloride of carbon. On heating on platinum foil it is decomposed with liberation of bromin. 634 ORGANIC SUBSTANCES Sajodin, Monoiodobehenate of Calcium, (C 21 H 4 2lCOO) 2 Ca Sajodin is a colorless, odorless and tasteless powder, insoluble in water. On heating it generates an abundance of iodin vapor; on exposure to light the superficial portion becomes yellow without material decompo- sition. It should contain 26 per cent of iodin and 4.1 per cent of calcium. It is used for the same purposes as potassium iodide. Ferro- sarjodin Basic ferric iodobehenate. Ferro-sajodin has the approximate formula (C2iH42lCOO)2(OH)Fe, and containing at least 5 per cent of iron and at least 24 per cent of iodin. It is a reddish-brown powder, unctuous to the touch, insoluble in water; soluble in chloroform and ether, on heating it melts to a brownish-black liquid, which emits an abundance of iodin vapors. It is indicated in conditions in which iron and iodin are employed, such as anemia, rickets, syphilis, chronic bronchitis, arteriosclerosis, etc. C erotic Acid Cerotic acid, C26H53COOH, occurs in Chinese wax as ceryl cerotate an ethereal salt corresponding with cerylpalmitate in spermaceti and in beeswax, and in the free state in the Carnauba wax. It no doubt occurs in many other waxes whose compositions have not been investigated. It is a white powdery substance when pure, melting 78-82° C. SOAPS The chemistry of soap is intimately connected with that of palmitic and stearic acids. Soluble soaps consist of sodium or potassium or ammonium palmitate or stearate or oleate, or mixtures of these, containing more or less water, often perfumed and medicated, and sometimes entirely liquid and con- taining ether or some solvent. The soaps with which we are especially interested are called medicated soaps. The official soap of the Pharmacopoeia is an olive oil soda soap in which of course the oleates predominate. Large quantities of soap are made from palm and cocoanut oils, stearin, and lard oil. Soaps contain varying amounts of water, the better grades little and the cheaper grades most. After the amount of water reaches a certain percentage, about 30 per cent, the soap will float. ORGANIC ACIDS 635 Medicated soaps are offered as remedies for skin diseases, as antiseptic washes, and for introducing oxygen into the system. The latter feature has come into vogue during very recent years in the so-called " peroxide " soaps. If a soap contains sufficient medicament to be of value from a thera- peutic standpoint, the essential ingredients can be readily detected. The sample should be dissolved in water or digested with water until disinte- grated, and then treated with an excess of dilute sulphuric acid, and poured into a separator and shaken with ether. The metallic bases and any alkaloids which might be present will be in the aqueous solution, and the fatty acids, phenols, cresols, iodoform, thymol diiodide and similar sub- stances will be. dissolved in the ether, and any bran, siliceous material and the like will remain undissolved. The acid aqueous solution is then drawn off, and a portion tested with a crystal of potassium chromate and a little absolute ether, and if peroxide is present a deep blue color will be imparted to the ether. The balance of the acid solution is then treated with excess of alkali and shaken with ether to remove organic bases which should be sought for after evaporating the ether, and the alkaline liquid treated with excess of hydrochloric acid and tested for metals, especially mercuiy and zinc, and also for borates. The ether solution containing the fatty acids, etc., should then be shaken with dilute sodium hydroxide, which will remove the acids and phenolic bodies, and then separated and the ether filtered, leaving the bran behind, evaporated and examined for iodoform, thymol diiodide and petrolatum. The alkaline liquid is then treated with excess of hydro- chloric acid and shaken with ether, the solvent filtered and cautiously evaporated and the residue treated with hot water, the water separated and filtered and examined for phenolic bodies, by noting the color given by ferric chloride, and precipitating with bromin water. The bromin precipitate can be purified and its melting-point determined. After a preliminary qualitative test, a quantitative estimation can be made along the same lines indicated. Mercury may be precipitated as sulphide and weighed, and zinc as sulphide, filtered, redissolved, and pre- cipitated as carbonate, ignited, and weighed as oxide. As a general thing it can be said of the soaps now in use, that the amount of metallic ingredients will be sufficient to give a good quantitative test, but that the phenolic bodies are only in minute quantities. Some soaps claim iodin as an ingredient, but it is usually in such small quantity that its detection is difficult, and its determination of little real value. Peroxide soaps are much in vogue, and if more than a trace of peroxide is present it can readily be detected by the method outlined above. If the sample does not respond to this reaction another test should be applied 636 ORGANIC SUBSTANCES with titanium potassium oxalate and any darkening noted. This latter reaction must, however, be considered with caution, because it has not yet been determined whether other substances present might give this same coloration. Soap is employed medicinally as a laxative, antacid, and antilithic and is often combined with rhubarb in remedies for dyspepsia, consti- pation, and biliousness. It has been recommended for urinary calculi, but is of doubtful value, though it should be looked for in such prepara- tions. It is often found in Hniments combined with opium, camphor, and potassium iodide. It is one of the chief constituents of the official soap liniment known as " liquid opodeldoc." Lead soap, which is really lead oleate, is known as lead plaster, and lime soap, lime liniment, or Carron oil, are well-known medicinal agents. Ammonia liniment consisting of olive oil partially or wholly saponified by ammonia in alcohol, is used for croup and inflammatory conditions of the throat. Solid opodeldoc is stearin sodium soap containing alcohol. Assay of Soap. — The moisture in soap is determined by dissolving about .5 gram of the sample accurately weighed in 10 mils of alcohol, and evaporating to dryness in tared dish containing 1 gram clean sand, which has been previously heated to 110°. The residue is dried at 110° to con- stant weight. Insoluble impurities and free alkalinity are determined by dissolving 10 grams in 100 mils of alcohol and filtering any undissolved residue into a tared Gooch and washing with hot alcohol. The residue is dried and weighed, and represents chloride, carbonate, and silica. It is then washed with boiling water, which dissolves the chloride and carbonate, and the silica can then be dried and weighed. Free alkalinity can be determined in the alcoholic filtrate by titrating with standard acid using phenol- phthalein. Fatty acids and total combined alkali metals are determined by using an alcoholic solution of the soap obtained as above. The alcohol is driven off over the steam-bath, the residue taken up with water, transferred to a separator, acidulated with sulphuric acid, and shaken with ether. The acid liquid is drawn off through a filter into a platinum dish, the filter washed, the solution evaporated to dryness and carefully ignited to constant weight as sulphate of the alkali metal present. The fatty acids are in the ether layer and may be estimated by evaporating the ether in a tared dish weighing the residue. Assay of Soap Liniment. — Specific Gravity. — Determine this value at any convenient temperature. Camphor. — Determine rotation in 200-mil tube, using sugar scale. Standard soap liniment averages about 65-70 per cent alcohol, and a solu- ORGANIC ACIDS 637 tion of camphor in alcohol of this strength in the proportion of 4.5 grams of 100 mils, rotates the scale about 9.5°. Alcohol. — Fifty mils are transferred to a distilling flask, diluted to 200 mils, and 100 mils distilled over. This distillate is transferred to a separator, saturated with sodium chloride, and shaken out with low- boiling petroleum ether to remove the volatile oils. The balance of the determination follows the directions given for determining alcohol in the chapter on general methods. Collect the pure distillate in a 100-mil flask. The percentage of alcohol corresponding to the specific gravity will be half that present in the sample. Fatty Acids and Alkali (Anhydrous Soap). — Evaporate the alcohol from a 50-mil sample. Transfer to separator, using water, and add a slight excess of dilute sulphuric acid. Shake out with ether, collecting ether extractions in another separator, washing, and finally evaporating to dryness in a tared beaker, the weight being the fatty acids. The acid liquid is filtered into a platinum dish, the filter washed, the solution evaporated to dryness, cautiously ignited and weighed as sulphate of the alkali present. By calculating the alkali to oxide (Na20 or K2O) and adding the result to the weight of the fatty acid, the final figures will be the quantity of anhydrous soap present. Good soap liniments will average slightly over 6 per cent anhydrous sodium soap. SEPARATION OF ACIDS OF ACETIC SERIES The acids of this series can be separated from each other in several ways. The lower members can be separated from the middle and higher acids by treating an aqueous mixture with calcium chloride and shaking out with ether. By this procedure all of the acids except formic and acetic will dissolve in the ether, and on drawing off the aqueous solution and washing the ether with a solution of calcium chloride, formic, and acetic will be found in the aqueous portion. They can be distilled off with steam from the calcium chloride after acidulating with tartaric acid and separated from each other by taking advantage of the difference in the solubilities of their lead salts in alcohol. The ether solution should then be evaporated and the middle members separated from the higher by washing out the residue with hot water. These acids, which are for the most part volatile, can then be separated by the method of partial saturation. The mixture is divided equally and one of the portions exactly neutralized with sodium hydroxide; the other half is then added and the whole distilled. As the acid strength dimin- ishes with the increase in the number of carbon atoms, the lower acid in the mixture will displace the higher. For instance, butyric acid will dis- 638 ORGANIC SUBSTANCES place valerianic acid, and if the mixture contained equal quantities of the two, the distillate would contain only valeric acid and the residue sodium butyrate. If the valerianic acid predominated, the aqueous solution would contain both butyrate and valerianate, and when distilled in the presence of phosphoric acid, would yield a fresh mixture of the acids which can be treated in the same way. If butyric acid were in greater amount the dis- tillate would contain both acids and must be again treated by partial saturation as before. The non-volatile acids may be separated by the fractional precipita- tion of their lead, barium or magnesium salts, the insolubility of which increases with the number of carbon atoms. The acid mixture is dissolved in alcohol and partially precipitated by an alcoholic solution of lead, barium, or magnesium acetate, the precipitate consisting largely of the acid of highest molecular weight. It is filtered and another precipitate obtained from the filtrate, which will consist of acids lower in carbon and so on. Each precipitate is then decomposed by hydrochloric acid and the new mixture of acids subjected to the same treatment until the sepa- rated acids yield constant melting-points. Another procedure for separating and determining the identity of the higher fatty acids depends on their conversion to their methyl esters and fractionating. Bull adopted this procedure when working with the acids of cod-liver oil. DETECTION AND ESTIMATION OF ACIDS OF ACETIC SERIES WHEN IN ADMIXTURE The free acids obtained by distillation are saturated by barium car- bonate or by the cautious addition of baryta water (using phenolphthalein to indicate the point of neutrality), the latter method being preferable for the higher numbers of the series. In this way, neutral barium salts are formed, which may be obtained in the anhydrous state by evaporating off the water and drying the residue at 130°. These barium salts contain percentages of barium dependent on the atomic weights of the fatty acids present. On moistening the residue with sulphuric acid and then igniting, an amount of barium sulphate is obtained proportional to the percentage of barium contained in the salt of the fatty acid present. Instead of weighing the barium sulphate, a standard solution of baryta water may be employed and the weight of barium (or its equivalent of barium sul- phate) calculated from the volume of solution employed. This method also serves as a useful check on the determination of the weight of barium sulphate. The following table shows the proportions of barium contained in, and of barium sulphate producible from the barium salts of the lower acids of the acetic series: ,he ORGANIC ACIDS 639 Name of Salt Barium, Per Cent Barium Sulphate, Per Cent Barium formate 70.25 53.73 48.41 44.05 40.41 37.33 34.68 32.39 30.38 28.60 119.47 Barium acetate Barium propionate Barium butyrate Barium valerianate 91.37 82.13 74.91 68.73 Barium caproate 63.48 Barium oenanthylate Barium caprylate 58.98 55.08 Barium pelargonate Barium caprate 51.66 48.64 From this table it will be seen that the pure barium salts of the lower acids of the acetic acids can very readily be distinguished from each other by estimating the percentage of barium contained in them. In the case of mixtures of two acids the identity of which is established, the propor- tions in which the two are present may be calculated from the following formula, in which x is the percentage of barium salt of the lower fatty acid in the mixed barium salts obtained ; P, the percentage of barium sulphate yielded by the mixed barium salts on treatment with sulphuric acids; B, the percentage of the same theoretically obtainable from the pure salt of the lower fatty acid; and b, the percentage of the same, theoretically obtainable from the pure salt of the higher fatty acid. Then Bx=100P+bx-100b. For example, suppose a mixed barium salt known or assumed to con- sist of acetate and valerate to have yielded a precipitate of barium sulphate equivalent 78.45 per cent of the weight taken, when treated with sulphuric acid and ignited. Then, by the above formula, therefore and 91.37s = 7845+68.73s 22.643 = 972, 3 = 42.93. 6873, Hence the mixed barium salt consisted of 42.93 of barium acetate, and 57.07 of barium valerate. From these data and the weight of mixed barium salt found, the actual amounts of acetic and valeric acid may be calculated. ACIDS OF THE ACRYLIC OR OLEIC SERIES, CnHna-x COOH The acids of this series are unsaturated and therefore show marked differences from those of the preceding series, but all reactions affecting 640 ORGANIC SUBSTANCES the carboxyl group are analogous. They combine directly with two atoms of bromin to form dibrom substitution products of the acids of the acetic series, thus oleic acid gives dibrom-stearic acid. When these dibrom acids are boiled with alcoholic potash they yield either monobrom substitution products of the acrylic series, or both bromin atoms are removed as hydrobromic acid and a new acid of the next series (propiolic) is produced. The higher members of this series are reduced to saturated acids by hydriodic acid. These acids on fusion with potassium hydroxide are converted to potas- sium salts of two members of the acetic series, the acids produced depend- ing on the position of the double bond; thus acrylic acid yields acetate and formate, and solid crotonic acid two molecules of acetate. The higher members are converted into crystalline isomerides by the action of nitrous anhydride. The Crotonic Acids Solid crotonic acid, CH3CH = CHCOOH, forms needles melting 72°, boiling 189° C. It is somewhat soluble in water, and has an odor like butyric acid, into which it is converted by nascent hydrogen. Liquid crotonic acid is apparently a stereoisomeride of the former, into which t is converted by heating to 180° C. The boiling-point is given at 172°. It is claimed to be present in croton oil. Methyl acrylic acid, CH2 = C(CHs)COOH, has been reported as occur- ring as an ester in oil of chamomile. It melts 16° and boils 160° C. Angelic Acid, CH 2 = CHCH(CH 3 )COOH This acid and its isomeride, tiglic or methyl crotonic acid, are impor- tant in our work. The former occurs as an ethereal salt in the oils of cumin and Roman chamomile and probably other species of Anthemis, and in Arnica montana, and also in angelica root. It forms monoclinic prisms or needles of a spicy odor, melting 45°, boiling 185°, soluble in alcohol, ether, and hot water. It may be obtained by boiling an extract of the root with alkali, filtering, acidifying with phosphoric acid, and distiUing. Tiglic acid, CH 3 CH = C(CH 3 )COOH, an isomer of angelic acid, is a liquid, occurs in croton oil, cumin oil, and chamomile, and is also a product of decomposition of some of the Cevadilla alkaloids. It apparently occurs in croton oil as a glyceride. It is obtained from cumin and chamomile oils with angelic acid. It differs markedly from angelic acid in being a vesicant, and will quickly produce blisters. ORGANIC ACIDS 641 The identification of angelic acid will not necessarily prove the presence of angelica root in a preparation, but if it is found without the accompany- ing tiglic acid, which seems to be absent in the drug, but which does occur in chamomile and cumin, the presence of angelica is probable. Angelic acid may be expected to occur in tonic mixtures, and in some cases the angelica will be apparent by its characteristic odor. It will also be found in hniments and local absorbents and application for ulcers and goiter, where it occurs in some of the tinctures recommended for such ailments, with arnica and chamomile. OLEIC ACID, C 17 H 33 COOH This acid is the most important of the oleic series, and is of interest to us because it is the acid constituent of the salt used to make lead plaster, and is used for making oleates. It occurs as a glyceride in many fats and oils used in ointments and for various other pharmaceutical purposes. It is sometimes used as a medicine in biliary colic. It is an oily liquid, solidifying at 0°, and melting again at 14° C, soluble in alcohol, ether, and chloroform. Under ordinary conditions it cannot be distilled without decomposition, but with superheated steam it goes over at 250°. On fusion with potassium hydroxide it gives acetate and palmitate. Nitric anhydride converts it into isomeric elaidic acid, which is a solid at ordinary temperature and melts at 45°. This s called the Elaidin test and is often applied to oils. It absorbs oxygen with con- siderable readiness, becoming darker in color and as recovered from oils as found in commerce, it seldom is in a chemically pure state. The alkali oleates are soluble in water, and if a large quantity of the solvent is present, insoluble acid oleates are formed. Barium oleate is insoluble in water. The lead salt is soluble in ether, differing markedly in this respect from the lead salts of the saturated acids. This property furnishes a means of separating oleic acid from stearic and palmitic acids. On digesting the mixed acids with litharge for an hour at 100° C, and then treating with ether, the oleate will dissolve together with small quantities of the other lead salts, and on shaking with dilute sulphuric or hydro- chloric acid the lead is precipitated and the pure acid recovered from the ethereal solution. It should not be taken for granted that an acid obtained by this procedure is necessarily oleic acid alone, or even oleic acid at all, for the lead salts of many other unsaturated acids occurring in fixed oils have not been investigated as yet. The oleates are prepared either by treating a metallic oxide or free alka- loid with oleic acid, or by double decomposition of a soluble solution of sodium oleate with a soluble salt of the metal. 642 ORGANIC SUBSTANCES HYDROXY AND DIBASIC ACIDS OF THE ALIPATHIC SERIES These acids may be considered as oxidation products of the glycols, and some of them are extremely important in medicinal chemistry, both from an analytical and therapeutic standpoint They may be divided into four groups. 1. Hydroxy monocarboxylic acids, of which lactic acid is important. 2. Dicarboxylic acids, including oxalic and succinic acids. 3. Hydroxydicarboxylic acids, of which tartaric acid is important. 4. Hydroxytricarboxylic acids, represented by citric acid. Hydroxy Monocarboxylic Acids Theoretically the simplest member of the group should be hydroxy formic O-H-COOH, or carbonic acid; the acid is not known in the free state, but as its anhydride, carbon dioxide. CH 2 OH ! Gly collie or hydroxyacetic acid, COOH, is obtained by boiling the potassium salt of monochloracetic acid with water. CH 2 ClCOOH-J-HOH = CH2OH+HCI. I COOH It is also produced on oxidizing glycol and by treating amido acetic acid with nitrous acid. Glycollic acid is a crystalline hygroscopic substance, melting 80°, and readily soluble in alcohol, water, and ether. It has both acid and alcoholic properties, neutralizing carbonates and forming salts, oxidizing to the aldehyde acid glyoxalic acid, and on further oxidation to oxalic acid. When the carboxyl group is esterified the hydroxyl may still be displaced by alkali metals and the acetyl group. When heated with sulphuric acid it is decomposed into formaldehyde and formic acid. Lactic Acids There are two lactic acids, a-hydroxypropionic or ethylidene lactic acid, CH3CHOHCOOH, and /3-hydroxy propionic, ethylene lactic or hydracrylic, CH 2 (OH)CH 2 COOH. The former exists in three modifications, dextro, lsevo, and inactive, and the inactive is known as fermentation lactic acid, the commonly occurring acid, and is formed during the fermentation of sugar, starch, etc., in presence of nitrogenous animal matter, and is present in sour milk. ORGANIC ACIDS 643 It will seldom if ever be found in the pure isolated state, but occurs as a thick syrupy aqueous solution, miscible with water, alcohol, and ether, but not with chloroform. It cannot be distilled, and is readily broken up on warming with dilute sulphuric acid, yielding acetaldehyde and formic acid. It functionates as an acid and a secondary alcohol. It forms metallic and ethereal salts, and the salts themselves will react with acetyl chloride with reactions affecting the hydroxyl group; it acts like a secondary alcohol giving a-brom propionic acid with hydrobromic acid, CH3CHOHCOOH+HBr = CH 3 CHBrCOOH+H 2 0, and propionic acid with hydriodic acid, the a-iodo acid first produced being reduced, CH3CHICOOH+HI = CH3CH 2 COOH+I 2 On oxidation with permanganate it is converted into pyruvic acid, a keto acid. CH3CHOHCOOH+O = CH3COCOOH+H2O - Nitric acid converts lactic acid to c :ialic acid, and chromic acid produces acetic acid, carbon dioxide, and water. Most of the lactates are soluble; the zinc and calcium salts are crys- talline and soluble in hot water. It does not give a precipitate with lead acetate. The zinc salt is precipitated when zinc sulphate is added to lactic acid neutralized with ammonia. Salts of the type CH3CHOMCOOM are known, thus sodium sodio-lactate is prepared by the action of sodium on sodium lactate. The combination of lactates with phosphates known as lac to phosphates, have an extensive use in medicine. Copper phosphate produces a deep-blue solution but no precipitate. The strength of the commercial acid is about 75 per cent, and when heated to 150° it is largely converted into a substance called concrete lactic acid or lactide, which is probably an anhydride. It has considerable solvent action on calcium phosphate, and is therefore used to remove tartar from the teeth. Lactic acid can be titrated directly with alkali hydroxides, using phenol- phthalein. When lactic acid syrup is evaporated at the ordinary temper- ature in dry air as in a desiccator, the anhydride and lactide are gradually formed, the same results occur when the acid is heated above 130° C. These substances are nearly insoluble in water, but are reconverted into lactic acid on boiling with water, or when treated with alkali hydroxides. In commercial lactic acid the anhydride commonly runs up to 10 per cent. Concentrated sulphuric acid does not blacken lactic acid in the cold, and on warming the mixture turns brown with copious evolution of carbon monoxide. When heated with dilute sulphuric acid, acetaldehyde and formic acid are evolved. When distilled with calcium oxide, carbon dioxide and ethyl alcohol are evolved. 644 ORGANIC SUBSTANCES Lactic acid gives a lead salt which is soluble in water, and a barium salt soluble in alcohol. Zinc lactate is insoluble in alcohol. A dilute solution of lactic acid on distillation with sulphuric acid and potassium bichromate yields formic acid and acet aldehyde. If the dis- tillate is conducted through barium carbonate as detailed under the Determination of Formic Acid, the presence of the latter can be detected, and the aldehyde identified in the final distillate. If a weak solution of the pure acid is heated to 100° with concentrated sulphuric acid for two minutes, portions of the product will give a rose-red color with alcoholic solutions of guaiacol, and an orange-red with alcoholic codein. The color is due to acetaldehyde. Glycollic acid would give formaldehyde and hence different coloration. Commercial lactic acid is tested for its content of free acid and anhy- dride by the following methods: Free Acid. — Twenty grams are diluted to 250 mils and 25 mils of the dilute solution titrated direct, as rapidly as possible in the cold with N/5 alkali, using phenolphthalein. One mil =.0181 gram lactic acid. The end-point is reached when a pink color appears, which remains on stirring. Anhydride. — Twenty-five mils of the same solution are boiled with a known excess of N/5 alkali for ten minutes, and after adding sufficient N/5 acid to neutralize the alkali, the excess of acid is titrated back with alkali. The difference between the first and second determinations gives the anhydride. The determinations of lactic acid and lactates in pharmaceutical mix- tures is still a problem of research. There are undoubtedly assay methods which give fairly accurate indications of the percentage values of the pure substances, but they are not applicable to mixtures. Inactive lactic acid can be separated into the two modifications by the difference in solubility of the strychnin or morphin salts, the laevo form being the least soluble. Dextro or sarcolactic acid occurs in juices of muscular tissue and in certain body excretions. Its anhydride and salts are laevo rotatory. It is almost completely precipitated from its solution by copper sulphate, while inactive lactic acid yields a deep-blue liquid. The lactic acids give the iodoform reaction. Ethylene Lactic Acid or Hydracrylic Acid This acid is also found in meat juices and is distinguished from ethyl- idene lactic acid in yielding no anhydrides, but acrylic acid and water when heated. When oxidized it yields carbon dioxide and oxalic acid. Its zinc salt is very soluble in water. Lactic acid is used as a remedy for dyspepsia, diarrhea, diabetes, the ORGANIC ACIDS 645 removal of phosphate in the urine, the removal of false membranes as in diphtheria and croup, in tuberculous affections of the mouth and throat, and for removing tartar from the teeth. It is also combined with pepsin,, as it is supposed to increase the solvent power of the ferment on food. Lactic acid is sometimes used in the form of sticks which consist of the acid and menthol held in a gelatin base. It is largely dispensed in syrups and elixirs, combined with alkali metals and calcium. The most important salts medically are those of calcium, magnesium, sodium, potassium, and hthium. Zinc lactate has been employed in epilepsy, and mercury and silver lactates in diseases of the mucous membrane. Glycerol mono- and di-lactates are used medicinally. A compound of lactic acid and santalol is prepared by heating the acid and oil of sandalwood at 130-140° for several hours. The product is purified by washing with water, bicarbonate and hydrochloric acid. It is a reddish-brown liquid, insoluble in water, but soluble in organic solvents. Estimation of Lactic Acid in Lactates. — The method which gives good results in some cases where other methods are either useless or too trouble- some, depends upon the oxidation of lactates in sulphuric acid solution, by means of standard potassium bichromate solution, when the following reaction takes place; 3C 3 H 6 03+2K2Cr207+8H2S0 4 = 2K2S04+2Cr2(S04)3+3C2H402+3CQ2+llH 2 0. An accurately weighed quantity of the material (about .4 gram), or an aliquot part of the solution after having been made up to a definite volume, is, after suitable dilution, boiled gently for one hour with 10 mils of 10 per cent sulphuric acid and 25 mils of N/2 potassium bichromate in an Erlenmeyer flask, fitted with a reflux condenser. The excess of potassium bichromate is titrated in the usual manner with N 10 sodium thiosulphate after the addition of 10 mils of 10 per cent potassium iodide and 1 drop of starch paste. One mil N/2 potassium bichromate corresponds to .01127 gram of lactic acid. If volatile matters which reduce chromic acid are present, they must be first removed by repeated evaporation. The presence of sugar, dextrin and similar materials renders this method useless, as they reduce chromic acid, and, moreover, cannot be separated. Good results are obtained with mixtures of double salts such as antimony calcium lactate and antimony sodium lactate, containing more or less great excess of free lactic acid. In this case, the antimony is first precipitated as sulphide by means of sulphur- etted hydrogen, excess of the latter being subsequently expelled by boiling. 646 ORGANIC SUBSTANCES Lactic anhydride is not oxidized by the above treatment, and if present must be first converted into lactic acid by heating with a slight excess of alkali. DICARBOXYLIC ACIDS The relationship of the acids of this class is shown by the following: COOH 1 COOH 1 COOH 1 COOH COOH / 1 COOH 1 COOH 1 COOH CH 2 CH 2 CH3CH CH 2 CH 2 (CH 2 ) 7 Oxalic 1 1 \ i 1 1 COOH CH 2 COOH CH 2 CH 2 COOH Malonic I Isosuccinic 1 | Azelaic COOH CH 2 CH 2 Succinic 1 COOH Glutaric 1 CH 2 1 COOH Adipic Oxalic acid is not of importance therapeutically, but its salts occur in certain plants, and its identity may be important in establishing the presence of a certain drug. Succinic acid and the succinates are used in medicine. The other acids are of interest to us only from their chemical relation to the group as a whole. Oxalic Acid Oxalic acid forms colorless crystals containing two molecules of water, readily soluble in alcohol and water, and sparingly in ether. It melts at 100°, losing its water, and at 150° sublimes. When heated to a higher temperature it is decomposed into formic acid and carbon dioxide, or to carbon monoxide, dioxide, and water. When heated moderately with concentrated sulphuric acid it is decomposed and gives the final products as above. It has reducing properties, precipitating gold, and is readily oxidized by permanganate. It is dibasic and forms salts with two equivalents of the metallic hydroxide, or with two molecules of a monohydric alcohol. It has fairly strong acid properties, decomposing carbonates and dissolving certain metallic oxides. The alkali oxalates are soluble in water, the acid alka- line salts and silver salts less so, and most of the other salts are insoluble or only sparingly. ORGANIC ACIDS 647 Succinic Acid Succinic acid crystallizes in colorless prisms, melting 180-182° and subliming readily. It is sparingly soluble in water, alcohol, and ether, and insoluble in chloroform and benzol. When strongly heated it forms the anhydride and the vapors produce coughing. It is very stable and little affected by oxidizing agents. It often sublimes without charring when strongly heated. When a soluble succinate is treated with ferric chloride, a rich brown precipitate is produced which might at first be mistaken for the precipitate given by benzoic acid. A solution is not precipitated by calcium or bar urn chlorides. Sodium succinate is used as a saline cathartic, and also in combating infections of the gall bladder and biliary tract. CH 2 CO x Succinic anhydride, | }0, is prepared by heating the acid with CH 2 CCK phosphorus oxy chloride for some time and then distilling. It is a color- less crystalline substance, melting 120°, and when boiled with water or an alkali is reconverted to the acid or a succinate. It is used in the prepa- ration of succinic peroxide, the chemistry of which has been described unde Peroxides. Succinic acid can be determined b}^ shaking out with ether from a solution acidulated with mineral acid, and weighing the residue left on evaporation. Ammonium succinate is used as a diuretic and an antispasmodic in cramps, hysteria, and delirium tremens. Isosuccinic acid melts 130°, and sublimes readily. It does not form an anhydride and when heated alone, or with water, it is decomposed into propionic acid and carbon dioxide. Identification of Succinic Acid — Treat .1 gram acid with .5 gram para- toluidin in a test-tube fitted with a cork stopper and an air cooler and heat for one-half hour in an oil-bath at 200-220°. Cool partially and add 10 mils dilute alcohol (1-1) and boil. Cool well and filter the succin- toluide. Wash with 2 mils alcohol (1-1), crystallize from 5 mils boiling strong alcohol, filter, wash with 1 mil strong alcohol, dry at 100° and determine the melting-point, which should be 254.5-255.5° C. Asparaginic, aspartic, or aminosuccinic acid, COOHCEkCHXNHs)- COOH, results when asparagin is boiled with acids or alkalies. It is sparingly soluble in cold water and alcohol, is readily soluble in hot water and alkalies. Asparagin occurs in many plants, but it has practically no use medicinally. 648 . ORGANIC SUBSTANCES HYDROXYDICARBOXYLIC ACIDS In this group we find malic and tartaric acids, the former of special interest to the food chemist, and the latter to the drug chemist. TARTARIC ACID COOH CHOH I CHOH I COOH Tartaric acid is extensively used in medicine. It is a refrigerant and an antiscorbutic, and in combination with alkalies is a mild laxative and diuretic. It enters into the combination of artificial effervescent mineral water salts and will sometimes be found in granular effervescent prepara- tions together with citr c acid. Seidlitz mixture consists of sodium and potassium tartrate (Rochelle Salt), sodium bicarbonate, and tartaric acid. Effervescent salts of the Carlsbad type contain sodium bicarbonate, tartaric acid, and sugar; of the Kissingen type, potassium and sodium chloride, magnesium sulphate, bicarbonate, acid, and sugar; of the Vichy type, sodium chloride, mag- nesium sulphate, potassium carbonate, sodium bicarbonate, acid, and sugar. As the bitartrate of potassium it will be found in combination with sulphur, and sometimes with camphor, opium, and Asclepias tube- rosa; and with ipecac, arsenous acid, sodium benzoate, and Capsicum. Tartaric acid should be 'ooked for whenever antimony is found, as it forms with this latter an important double salt known as Tartar Emetic. The various combinations containing this substance are described more fully under Antimony. Tartaric acid exists in several forms, and their study from the point of view of stereoisomerism has been exhaustively considered and detailed at length in works on theoretical organic chemistry. These forms include the dextro, laevo, racemic or uvic, and meso. The racemic and meso are inactive, and the racemic can be resolved in both dextro and laevo by appropriate means, but the meso cannot. The dextro is the acid of common occurrence and is the form in which we are interested from an analytical standpoint. The pure acid forms anhydrous, colorless, transparent rhombic prisms, melting 168-170° C. but not sharply as decomposition takes place. Specific gravity 1.74-1.75. It is readily soluble in water and alcohol, very slightly ORGANIC ACIDS 649 in ether, and almost insoluble in chloroform and benzol. It chars with sulphuric acid or when slowly ignited, emitting the odor of burnt sugar. When heated some time at 150° it gives the anhydride and other com- pounds. Neutral potassium salts give a crystalline precipitate with free tartaric acid, insoluble in acetic acid, but dissolving in mineral acids and alkalies. This precipitation is prevented if boric acid is in solution, which must be borne in mind when tablets are being tested, as boric acid is often present in tablets as a lubricant. A solution of the free acid nearly neutralized with ammonia should give no precipitate with calcium sulphate. Oxalic and racemic acids will give a precipitate with this test. When warmed in the presence of ammoniacal silver oxide, a silver mirror is deposited on the walls of the containing vessel. Cinchonidin sulphate gives a white crystalline precipitate with free tartaric acid or its ammonium salt. When a neutralized solution of tartaric acid is treated with a calcium salt, a precipitate is thrown down which is soluble in potassium hydroxide but which comes down again on boiling. The precipitate is also soluble in ammonium chloride. Calcium racemate is insoluble in acetic acid and nearly so in ammonium chloride. Tartaric acid is broken up into the acetate and oxalate on fusion with potash. Nitric acid oxidizes it to oxalic acid. Tartaric acid in solution prevents the precipitation of iron and aluminum by alkalies. Tartaric acid reduces alkaline permanganates. The important salts of tartaric acid are the following : Sodium and potassium tartrate. Rochelle salt or Seignettes salt. Potassium antimonyl tartrate. Tartar emetic. Potassium hydrogen tartrate. Cream of Tartar. Salt of tartar is a misleading name applied to potassium carbonate. When barium chloride is added to a solution of tartar emetic a pre- cipitate is formed according to the equation. 2KSbOC4H406+BaCl2 = Ba(SbOC4H40 6 )2+2KCl. The barium salt on decomposition with sulphuric acid gives an acid solution which soon deposits antimonous hydroxide, but if it is neutralized with potassium hydroxide before decomposition occurs it yields tartar emetic. It would indicate that the emetic was the potassium salt of a tartaric antimony acid, which has been called tartryl antimonous acid, and hences the emetic would be potassium tartryl antimonite. When SD2O3 is dissolved in tartaric acid, antimonyl tartrate (SbO)2- C4H4O6 is produced, and crystallizes from the solution on adding alcohol. 650 ORGANIC SUBSTANCES When this is boiled with normal potassium tartrate it is converted tartar emetic, (SbO) 2 C4H406+K2C4H40 6 = 2KSbOC4H406. Anilin antimony tartrate, GiHsOeSbOCeHyN, is soluble in water, sparingly in alcohol, gives a violet color with calcium chloride, a white precipitate with hydrochloric acid, soluble in excess and a white precipi- tate with nitric acid soluble in large excess. Cobalt nitrate solution gives a red color when added to an alkali tar- trate, the coloring being discharged on adding excess of sodium hydroxide. If the alkaline solution is boiled a deep-blue color appears on again heating. Alkali citrates give an immediate deep-blue color in the cold with cobalt nitrate in the presence of alkali. Tartar emetic does not behave like other tartrates with cobalt nitrate, the reaction being similar to that obtained with citrates. A solution containing free tartaric acid yields a crystalline precipitate in the cold with 10 per cent solution of calcium formate, having a character- istic microscopic appearance. Citric acid gives no reaction in the cold, but on warming, a crystalline precipitate is obtained. Detection of Tartaric Acid in Mixtures. — An aqueous solution of the product is precipitated with excess of lead acetate and the precipitate filtered, washed with water, and 50 per cent alcohol until free from lead, and the precipitate decomposed by hydrogen sulphide in the presence of a little ammonia. The solution is filtered from the lead sulphide and boiled to expel the excess of ammonia, and any ammonia sulphide formed, filtered again if any sulphur is precipitated, and portions tested as follows : Ammoniacal silver oxide will give a silver mirror on warming; calcium chloride gives a precipitate in the cold, becoming granular on boiling and soluble in acetic acid; cinchonidin sulphate gives a precipitate of white needles not always appearing at first but gradually appearing as the solu- tion stands. The accompanying table shows the comparative reactions of the free hydroxy acids and their salts. Determination of Tartaric Acid. — Tartaric acid when it occurs by itself can be estimated without difficulty, and when it occurs simultane- ously with citric .acid the potassium method will give good results. The accurate determinations of citric acid in presence of tartaric acid is still a matter for study. Tartaric acid in an aqueous solution can be titrated directly with alkali using phenolphthalein as an indicator. Tartaric in mixed preparations can be determined with fair accuracy by the method recommended for the determination of the total acid in wines. The method of the Association of Official Agricultural Chemists 1 is quoted herewith: » Jour. A. 0. A. C, Vol. 1, p. 240. to ORGANIC ACIDS 651 Quini- din. ft o -4 a ft o a o a a o Z li p. a o Z a a o 2 a a o 4J a a o 2 +5 a a 2 a a O 2 43 a a o 2 ft ft o z a a o Z p. o. o Z s S3 o ft ft o 2 ft Z 03 } CO ft) 1 ft) .-§1 l .-si o 2 5 a a o a o 2 a o z a a o Z O Z "ft o Z ft a o z ft ft o 2 o s c ft ft o z ft o 2 ft ft 55 a a c ft a c 2 ft - ft o Z a a o 2 a a a o 2 6 a o 2 a o 2 ft a o z O a o z ft ft o Z .1-1 s .2 o 3 73 ft) 3 Z 3 73 93 3 O o 3 73 o Pi 3 ft) 3 ft) 3 .2 o 3 73 ft) Pi 3 .2 o 3 0) Pi 3 _c o 3 73 D 3 _o ft) 3 0) Pi 3 .2 o 3 73 ft) Pi 3 O +a o 3 - 3 .2 3 73 ft) 3 O o 3 73 ft) 12 o t- 73 >> w £ 3 O o OQ P.* Ph ft) .3 00 ftS -3 "Is ■ a — » 3 O 73 3-3 3^ 3 O 73 ft) bfi ac 3 3^ P 3 O T3 bC * 3 ° 3 a o a o a o 2 P, a o z a o Z ft a o Z O ft ft o 2 o 2 o Z • co ~*Z. 5C S" U o © Si jj =0 p. 8 "3 k a t, a ^ ^'1 ft o 2 o o 2 ft o 2 A o Z a o z: o 4) o oj o o si a o O tab o O ti O O bii sj O O O O ft ft a a o 2 ft ft o 2 a 0) IS ft ft 0) IS a a a) IS g 4) IS ft 4) IS PS ft ft 4) IS •d 'o O ft ft ft ft) IS ft a 4) IS a 0) IS a 4) IS a «) IS ft a o a a o 2 a a 2 a 4) IS ft a 0) IS a a IS ft ft 4) IS a a 4) IS ft ft ft) IS 3 ft ft o IS ° M °° 3 a o is .3 X «rH ft) <5 1 3 u i g IS 3 &2 — 3 m 3 ^3 ".2 2 a IS ft a 4) IS p. a 4) IS p ft 4) IS ft ft 4) IS ft ft 4) 1 2 2 1 DO OQ 1 1 1 i OQ CO I o o ft ft 0) IS a 4) O ft) 3 3 3 § o8 1 & S 3 cq O o o o j) CO IS O co IS c © a a 0) — IS ft ft ft) IS 2 o O o o o o a a «) IS a a a; IS o o o © © © © a a «) IS ft ft 4) IS o o o JO oo >> u -2 0) tn ft) o o o o o © o o ° © !2 < O 73 o 12 < o 3 3 r 3 02 d < a ft) o < 4) o 73 O OQ 73 <: = OQ c 3 £ < o 3 73 o GQ 73 < £ IS 73 O 652 ORGANIC SUBSTANCES Neutralize 100 mils of the wine with N/1 sodium hydroxide, calculating from the ac dity, as determined by titration, the number of mils of N/1 alkali necessary for the neutralization. If the volume of the solution is increased more than 10 per cent by the addition of the alkali, evaporate to approximately 100 mils. Add to the neutralized solution .075 gram of tartaric acid for each mil of N/1 alkali added and, after the tartaric acid has dissolved, add 2 mils of glacial acetic acid and 15 grams of potas- sium chloride. After the potassium chloride has dissolved, add 15 mils of 95 per cent alcohol by volume, stir vigorously until the potassium bitar- trate starts to precipitate, and then let it stand in an ice box for at least fifteen hours. Decant the liquid from the separated potassium bitartrate on a Gooch, prepared with a very thin film of asbestos, or on filter paper in a Buchner funnel. Wash the precipitate and filter three times with a few mils of mixture of 15 grams of potassium chloride, 20 mils of 95 per cent alcohol by volume and 100 mils of water, using not more than 20 mils of the wash solution in all. Transfer the asbestos or paper and precipi- tate to the beaker in which the precipitation was made, wash out the Gooch or Buchner funnel with hot water, using about 50 mils in all, heat to boiling and titrate the hot solution with N/10 sodium hydroxide, using phenolphthalein as an indicator. Increase the number of mils of N/10 alkali required by 1.5 mils to allow for the solubility of the precipitate. One mil of N/10 alkali is equivalent, under these conditions, to .015 gram of tartaric acid. Subtract the amount of tartaric acid added from this result to obtain the grams of total tartaric acid per 100 mils of wine. Method Using Calcium Chloride. — Dissolve 5 grams of the tartrate- containing body in hydrochloric acid, filter if necessary. Neutralize with sodium hydroxide free from carbonate, add an excess calcium chloride, and after allowing to stand for some time collect the precipitate on a filter. Wash, dry, ignite, titrate with N/1 hydrochloric acid. Every 100 mils of N/1 acid required to neutralize CaO or CaC03 resulting from the ignition represents 7.5024 grams H2C4H4O6. Kling and Florentine l have proposed a method for determining tar- taric acid which they claim is of special application when working with products containing iron, aluminum, and antimony. Ammonium citrate is employed to replace the tartaric in its combinations with the metals mentioned. The following solutions are required: (a) Ammonium citrate 5 per cent; (b) ammonium Z-tartrate free from d-tartrate, 2 per cent, preserved with 5 mite formaldehyde; (c) calcium acetate prepared by dissolving 16 grams calcium carbonate in 120 mils acetic acid and making up to 1 liter; (d) hydrochloric acid containing 40 grams at 22° B., per liter; (e) 5 grams calcium carbonate dissolved in 20 grams acetic acid Orig. Com. 8th Intern. Congr. Appl. Chem., 1, 237; Bui. Soc. Chem., 11, 886. ORGANIC ACIDS 653 with 100 grams of sodium acetate per liter; (/) potassium permanganate, 1.6 per cent, standardized against a known solution of tartaric acid. The tartaric acid is estimated by dissolving the sample in 150 mils water and treating the solution with 10-15 mils of solution (a), then 25 mils of solution (b), and 20 mils of solution (c), mixing and allowing to stand for twelve hours. It is then filtered, washed with cold water, and the precipitate transferred into another container, using 20 mils of solution (d) which dissolves the racemate, made up to 150 mils; 40-50 mils of solution (e) added and heated to 80° C. on a water-bath. When the solution has cooled and the precipitate settled, it is filtered, washed, dissolved in 10 per cent sulphuric acid, and titrated with permanganate. The factor obtained for tartaric acid in the racemate is divided by two and the amount of ^-tartaric in the original solution determined. Analysis of Granular Effervescent Salt. — Make a thorough admix- ture of sample, separate about 15 grams powder in a mortar and transfer to a weighing bottle. (1) Weigh out exactly about 1 gram and determine the total CO2 in absorption apparatus. Calculate to sodium and potassium bicarbonates. (2) Determine phosphoric acid in .5 gram and calculate to sodium phosphate, Na 2 HP0 4 2H 2 0. (3) Determine chlorine in 1 gram and calculate to sodium chloride. (4) If magnesium is present determine in 1 gram and calculate to magnesium sulphate, MgSC^TEbO. (5) Determine sulphate in 1 gram and calculate to MgSQiTH^O, and if any excess calculate to Na2SO4l0H 2 O. (6) Dissolve 1 gram in water, boil, and titrate. If acid, calculate to mixed citric and tartaric acids. This figure will give the acid in excess of that necessary to neutralize the bicarbonates. To determine the amount used up by the bicarbonates, figure back from the results obtained in Xo. 1. This amount plus the amount found in excess will give the total acids. The final figure is of course only approximate, but it will often come out within 1 to 2 per cent of the quantity known to have been added. There is no method of determining the relative quantities of citric and tartaric acids in a mixture of the two. If the sample is alkaline, the determination in No. 1 of the total bicar- bonate minus the excess alkalinity (figured to bicarbonate) will give the amount of alkalinity consumed by the mixed acids and from which figure they may be calculated. • In the official granular salts the proportion of tartaric and citric acids is about 3 to 2. (7) Determine caffein in a 1-gram sample. (8) If hexamethylenetetramine is present, determine ammonia in a 5-gram sample and calculate to hexamethylenetetramine. Caution must 654 ORGANIC SUBSTANCES be observed, too, in keeping sample dry and to add undiluted concentrated sulphuric acid. (9) Determine moisture in 1 gram by drying in vacuo over sulphuric acid. (10) Make a qualitative test for Hthium with spectroscope, and if advisable determine the quantity. Many commercial tartaric acids and tartrates contain small quantities of lead, and their wholesomeness has become a problem for the food chem- ist. We are not especially concerned with the feature, but it may happen that the purity of a sample with respect to lead will be a question of importance in our work. The small quantity present is usually determined by color comparison, which is not a very safe method unless the absence of other heavy metals has previously been ascertained. Hence, in cases of moment or doubt the analyst ought to run careful qualitative tests before he attempts to arrive at any conclusions as to the quantity present. HYDROXYTRICARBOXYLIC ACIDS This group is represented by Citric Acid COOH I CH 2 I C(OH)COOH I CH 2 I COOH. Citric acid is used to considerable extent in medicine, occurring in a variety of products exploited for refrigerant and laxative purposes. It is somewhat antiseptic and antiscorbutic, is employed in pruritis, diph- theria, post partum hemorrhage, gangrene, sore mouth, excessive sweat- ing, inflammation of the throat, and scurvy. Ammonium citrate is almost always present in preparations containing beef peptones, such as beef, iron and wine, and cod-liver oil wines. It is present in granular effervescent salts and lithia tablets, and in combination with magnesium. It is a constituent of anti-fat mixtures combined with sugar. Citric acid crystallizes with one molecule of water. When heated -it dissolves in its water of crystallization and at 75° the water begins to evaporate. It becomes anhydrous at 135° and melts between that temper- ature and 152° C. Citric acid is efflorescent in warm air and deliquescent in moist air. Its presence in a sample is soon manifested if it is left exposed ORGANIC ACIDS 655 in a laboratory. It dissolves in the water it attracts, and if sugar is present forms a sticky unsightly mass which is difficult to dry. At a high temperature it gives aconitic acid, and on further heating itaconic and citraconic. When slowly ignited it is gradually decomposed without the odor of burnt sugar and it dissolves in hot sulphuric acid with a brownish-yellow color, instead of the charring phenomenon characteristic of tartaric acid. It is readily soluble in alcohol and water, slightly in ether, and prac- tically insoluble in chloroform, benzol, and petroleum ether. It gives no precipitate with potassium chloride or acetate. Calcium hydroxide in excess gives a precipitate on boiling, which redissolves on cooling. When this test is performed, a little calcium may be precipitated by the carbon dioxide in the air, and when the solution is cooled the pre- cipitate will not entirely dissolve. Calcium citrate is insoluble in potassium hydroxide, but soluble in ammonium chloride and acetic acid. Neutral citrates are precipitated by calcium chloride on boiling, but free citric acid gives no precipitate. It does not reduce alkaline permanganate nor ammoniacal silver oxide. Citric acid in solution prevents the precipitation by alkalies of iron and zinc. It dissolves iron oxide, and on evaporating the liquid it will remain clear and finally scale when dry; tartaric acid dissolves the oxide, but on evaporating a precipitate occurs. Fusion with potash gives acetate and oxalate. When heated with hydriodic acid it is converted to tricarballylic acid, COOH • CH = (CH 2 COOH) 2 . Detection of Citric Acid. — Citric acid can be precipitated from its solution by lead acetate and the precipitate washed and decomposed by hydrogen sulphide exactly as described under the Detection of Tartaric Acid. The solution of ammonium citrate should then be tested with cal- cium chloride, calcium hydrate, and the other reagents noted in the table on page 651. L. Gowing-Scopes J proposes the following method, which he states is accurate in the presence of tartaric, succinic, oxalic, benzoic, and phos- phoric acids, but when malic, lactic, or salicylic acids are present the results are too high. The sample containing not over .04 gram of citric acid is exactly neutralized with N/10 alkali, using phenolphthalein, treated with 10 mils of a reagent (consisting of 68 mils cone, nitric acid, 51 grams mercuric nitrate, 51 grams manganese nitrate; 100 mils water, finally made up to 250 mils and filtered) diluted to 200 mils and heated three hours with a reflux. The precipitate is washed by decantation, 1 Analyst, 1913, 38, 12. 656 ORGANIC SUBSTANCES collected in a tared Gooch, and dried at 100° for five hours, one-sixth of the weight of the precipitate gives the amount of citric acid. The residue should be cream colored, any yellowish coloration indicating the formation of basic salts, which will cause too high results. Citric Acid in citrates and lemon juice * The method consists in decomposing the citric acid (first separated as calcium citrate) by gently warming with concentrated sulphuric acid and measuring the evolved carbon monoxide, 1 molecule of which is obtained from each molecule of citric acid. The apparatus used is shown in the accompanying figures. The upper part A is fitted to the flask B f=£? (150-mil capacity) by a ground joint, and the tubes D and Eand G and E may be connected respectively through the tap R, as also may the flask and the exterior. Two grams of the calcium citrate, moistened with water, are introduced into B, and the air in the flask is completely displaced by carbon dioxide, the absence of air being ascertained by means of an auxil- iary nitrometer, filled with potassium hydroxide solution (1:5) and attached to the T-piece; 25 mils of concentrated sulphuric acid are then run into B from A, and a slow current of carbon dioxide is again passed into the flask, which is warmed to 80-100° C. and occasionally shaken, the carbon monoxide evolved being collected in a nitrometer of 200 mils capacity, of which the lower part B 1 (100 mils capacity) is graduated in fifths of a mil. When the volume of gas becomes constant, the nitrom- eter is allowed to stand for half an hour and then, after washing the gas with potassium hydroxide solution, introduced through J, the volume is read, and the usual corrections are made for temperature and press- 1 M. Spica., Chem. Zeit., 1910; 34, 1141. ORGANIC ACIDS 657 ure. One mil of carbon monoxide, at 0° C. and 760 mm. indicates .009407 gram of citric acid (C6H6O7, H2O). The same apparatus may be used for the determination of carbonate in a citrate, by decomposing with a known volume of concentrated hydrochloric acid and measuring the evolved carbon dioxide over water. Citarin Sodium anhydromethylene citrate is the normal sodium salt of anhydromethylene-citric acid. CH 2 COONa | yCH 2x CO< >0 I X CO / CH 2 COONa Citarin Anhydromethylene-citric acid is obtained by reacting on citric acid with paraformaldehyde, or with chlormethyl alcohol, CH 2 C10H. It is a white, granular, somewhat hygroscopic powder, having a faintly saline and aciduous taste, and a slightly acid reaction. It is readily soluble in about 1.5 parts of water, but insoluble in alcohol. Its solution splits off formaldehyde when heated, particularly in the presence of alkalies, and mineral acids separate from its concentrated solutions methylene- citric acid. It is incompatible with acid and alkalies and is decomposed by heat. It is claimed to be useful for gout and chronic rheumatism. Aconitic Acid COOH I CH 2 I CCOOH II CH I COOH This acid is produced on heating citric acid to a high temperature. It occurs naturally in aconite tubers, larkspur, black hellebore, yarrow, Equisetum, and probably other plants. CHAPTER XVIII ORGANIC ACIDS— AROMATIC SERIES CARBOXYLIC ACIDS The aromatic carboxylic acids may be considered as derived from the hydrocarbons of that series by the substitution of one or more carboxyl groups for a corresponding number of hydrogen atoms. Two classes of compounds may be obtained, depending on whether the substitution is in the nucleus or in the side chain. Thus we may have toluic acid, /CH3 CeH4NH+2H 2 x COOH x CO / The sulpho acids yield hydroxy acids when fused with potash. Mohler's x test for benzoic acid, modified by von der Heide, 2 has been used extensively at the Bureau of Chemistry in testing food products. The suspected residue is dissolved in 1-3 mils of N/3 sodium hydroxide and evaporated until all the water is driven off. To the residue 5 to 10 drops of concentrated sulphuric acid and a small crystal of potassium nitrate are added, and the mixture heated ten minutes in a glycerol bath at 120-130°, or for twenty minutes in a boiling water-bath. Meta-di-nitro benzoic acid is formed and the mixture is cooled, 1 mil water added and an excess of ammonia and boiled to break up any ammo- nium nitrite which may have been formed. After cooling, the solution, which should be in a test-tube, is treated with a drop of freshly prepared colorless ammonium sulphide without allowing the layers to mix, and the appearance of a red-brown ring indicates benzoic acid; on mixing, the color diffuses through the whole liquid, and on heating changes to greenish yellow, owing to the decomposition of the amido acid. Both cinnamic and salicylic acids yield amido acids, which give a red-brown ring, but the color is not destroyed on subsequent boiling. Phenolphthalein interferes with the test. Jonescu 3 recommends a simple test in which the suspected residue is dissolved in water slightly acidified with acetic acid, and ferric chloride and a few drops of hydrogen peroxide added. The liquid assumes a yellow tint, which gradually becomes violet owing to the conversion of benzoic acid to salicylic. Modified Jonescu Reaction. — One to 5 mg. of the acid in aqueous solu- tion are treated with 3 drops of ferric chloride (26 per cent (anhydrous basis) diluted 1-10), 3 drops hydrogen peroxide 1-10, and 3 drops ferrous sulphate 3 per cent, shaking after each addition. In about thirty seconds the reaction commences and the violet coloration attains its maximum in five to ten minutes. In the general scheme of analysis of medicinal preparations, benzoic 1 Bui. Soc. Chim., 1890, 3 (3), 414. 2 Zts. Nahr. Genussm., 1910, 19 (3), 137. 3 J. Pharm. Chem., 1099 (4), 29, 523. 662 ORGANIC SUBSTANCES acid will appear on shaking out the acid solution with petroleum ether. If none comes out at this point, but on shaking out subsequently with ether an impure residue is obtained which on testing apparently contains benzoic acid, it is evident that a small quantity only is present in the prod- uct. The residue left on evaporating petroleum ether is always purer than that obtained with ether, for this latter solvent has a solvent action on a wider range of substances. The crystalline residue should be examined first by allowing it to remain on top of the water-bath, but not over the direct steam, and observ- ing any sublimate which may collect on a watch-glass placed over the top of the receptacle. Benzoic acid soon collects in beautiful iridescent stalactites which can be easily scraped off and their melting-point deter- mined. The sublimate should also be subjected to Mohler's reaction and another portion dissolved in dilute ammonia, evaporated, and a solution of the residue treated with a drop of ferric chloride. Salicylic acid sublimes more slowly than benzoic and collects in quantity on the sides of the flask. Acetanilid also sublimes and might be mistaken for benzoic acid, but it is readily detected by the carbylamine reaction. Cinnamic acid does not sublime under these conditions. If salicylic acid or acetanilid occur simultaneously with benzoic acid, they should be separated before making the chemical test. The residue may be dissolved in water with a little acetic acid and precipitated with bromin water. On filtering, the benzoic acid will be in the filtrate, and after destroying the excess of bromin it can be shaken out and tested. Before attempting to determine the quantity of benzoic acid in a drug product, it is absolutely necessary to identify the other ingredients, and if other acids are present, their influence on the method must be taken into consideration, and appropriate procedures for their elimination con- ducted. If the sample is a tablet it should be thoroughly extracted with alcohol and the solvent evaporated in the presence of a slight excess of alkali. If the sample is a liquid the alcohol should be evaporated under similar conditions. The residue is then diluted with water, transferred to a separator and slight excess of hydrochloric acid added. It is then shaken with four successive portions of chloroform, using 70, 50, 40, and 30 mils, the combined solvents washed with water or saturated sodium chloride, the chloroform partly recovered by distillation and the balance evaporated to dryness in a beaker at room temperature, using a blast of dry air to hasten the evaporation. The residue of benzoic acid is dissolved in neutral alcohol, about one-fourth the volume of water added, and titrated with N/10 sodium hydroxide, using phenolphthalein as indicator. One mil N/10 alkali = .01217 benzoic acid. Salicylic acid if present can be separated and determined at the same ORGANIC ACIDS— AROMATIC SERIES 663 time by dissolving the chloroform residue in warm water acidulating with acetic acid, cooling, and precipitating the salicylic acid with excess of bromin water, filtering and weighing the tribromphenol bromide as described under salicylic acid, and then shaking out the benzoic acid from the filtrate exactly as described above. If phenolic substances are present the residue must be dissolved in chloroform and shaken out three times with 10 per cent sodium bicar- bonate, which will remove the acids, and the alkaline solution acidified and again shaken out with chloroform. Cinnamic acid can be determined in presence of benzoic by treating a solution faintly acid with sulphuric acid with excess of standard bromin in potassium bromin, and after allowing the mixture to stand tightly corked, agitating occasionally, potassium iodide is added and the liber- ated iodin titrated with thiosulphate. The dilution of the cinnamic acid should be about 1-200. This method permits the simultaneous determination of both acids. The titration or gravimetric figure for the two is obtained, and then the solution in alkali is acidulated and the cin- namic acid determined. Garsed 1 described this method in his work on the Assay of Crude Cocain. There are a number of proprietaiy products containing small amounts of aromatic balsams the presence of which can be ascertained by detecting the acids. If the sample is evaporated until all the water is driven off and then extracted with alcohol, the balsams will dissolve, and on con- centrating and adding a little potash and boiling, the ester will be saponi- fied and on evaporating the alcohol, dissolving in water, acidifying with hydrochloric acid and shaking with ether or chloroform, the benzoic or cinnamic acid or both will go into solution, and on carefully evaporating the solvent they will be left in the residue and can be identified. HIPPURIC ACID. BENZOYL AMINO ACETIC ACID, C 6 H 5 CONHCH 2 COOH Hippuric acid occurs in the urine of herbivorous animals, from which it may be obtained in crystals, melting 187.5°. It decomposes at a higher temperature, giving a sublimate of benzoic acid and an odor suggestive of hay, followed by one characteristic of hydrocyanic acid. It is difficultly soluble in ether and cold water, more readily in hot water, and easily in alcohol and ethyl acetate. Calcium hippurate is used in cystitis, lithiasis, difficult dentition, and uric-acid diathesis. Methylene Hippuric Acid — Hippol This substance, about which there seeems to be some ambiguity as to its formula, is used as an urinary antiseptic. It melts 151°, and is soluble in alcohol, chloroform, ethyl acetate, and slightly in water. 1 Pharm. J., 1903, 784. 664 ORGANIC SUBSTANCES SACCHARIN yS0 2 v c 6 hZ )>nh Saccharin is sold under a variety of names, including garantose, gluside, glycophenol, glycosine, saccharinol, saccharinose, saccharol, saxin, sykose, zucherin, glusimide, agucirina, toluolsuss, neo-saceharin, etc. It is prescribed in cystitis and for sweetening foods and preparations used in diabetes and for obesity; to cover the bitter taste in certain prod- ucts, and as a general sweetener in pharmaceuticals. It is usually sold in tablet form with or without sodium bicarbonate. It is a common sweetener used in tooth pastes. It is a white or yellowish, odorless, microcrystalline powder, melting 220°, somewhat soluble in water, and completely soluble in alkaline solu- tions from which it is precipitated on the addition of mineral acid if the solution is concentrated. It dissolves readily in alcohol and ether, but is practically insoluble in petroleum ether, chloroform, and benzol. It is best known on account of its intense sweet taste, which is apparent at considerable dilution. In order to compare its sweetening power with that of other substances, equal amounts should be dissolved in water con- taining, if necessary, sufficient bicarbonate to effect solution, and then each solution diluted until no sweet taste is apparent, the difference in dilution being a measure of the comparative sweetness. As it appears in analysis, saccharin is usually an amorphous residue which is left on evaporating the ether shake-out from an acid solution. It will be indicated on removing a small quantity on the end of the finger and touching it to the end of the tongue. Its presence should be further substantiated by dissolving the residue in ether and shaking out with dilute sodium hydroxide, which will remove the saccharin, but will leave any dulcin or other sweetener in the ether. The alkaline solution is trans- ferred to a test-tube, immersed in an oil-bath, the water evaporated and the temperature raised to 250° and held at that point for about twenty minutes. The alkaline mass is then dissolved in water, acidulated and shaken with ether, and the residue left on evaporation tested for salicylic acid, which results on fusing saccharin. The absence of salicylic acid in the original material must be assured by previously testing a portion with dilute ferric chloride. If salicylic acid is found, it can be separated by dissolving the residue in warm dilute hydrochloric acid, cooling, precipi- tating the acid with bromin water, filtering and boiling the nitrate to expel the excess of bromin, then adding a piece of sodium hydroxide and proceeding with the alkaline fusion as described above. ORGANIC ACIDS— AROMATIC SERIES 665 Dulcin is an entirely different chemical substance and may be con- sidered either as a derivative of urea or phenetidin: /NH 2 /OC2H5 C^O or C 6 H4< \NHC6H4OC2H5 x NHCONH 2 It is also used as an artificial sweetener, but is not as intense in its power as saccharin. Licorice root contains a sweet substance, glycyrrhizinic acid, and Eupatorium rebaudianum also contains a sweet principle. Saccharin can be readily determined when it occurs by itself or with bicarbonate, by dissolving the tablet in water, and precipitating with hydrochloric acid and shaking out with ether. On filtering and evapor- ating the ether the saccharin will be left as a weighable residue. It can be separated from salicylic acid by means of bromin water, after the manner described for separating that substance from benzoic acid, and then shaken out with ether and weighed. When it occurs in mixtures with other substances soluble in chloro- form these may be dissolved out by the chloroform and the saccharin subsequently shaken out with ether. This method applies to products of the headache remedy type containing caffein, acetanilid, or acetphene- tidin, all of which are removed from an acid solution by shaking out with chloroform. Soluble saccharin is prepared by treating saccharin with sufficient aqueous ammonium carbonate to render it soluble and evaporating the solution to dryness. PHTHALIC ACIDS These are dibasic acids, and the ortho acid is the most important. Ortho phthalic or benzene-o-dicarboxylic acid, |COOH COOH is a colorless crystalline substance, melting at 184° with formation of the anhydride, this being the only phthalic acid capable of forming an anhy- dride. If the melting-point of the new substance is taken it will be found to be 128°. The acid is soluble in water, alcohol, and ether, and forms well-defined metallic salts and esters. When heated with resorcinol and a drop of sulphuric acid, fluorescein is produced, and the reddish-brown product when dissolved in dilute alkali and poured into water gives a yellowish-green fluorescent solution. This 666 ORGANIC SUBSTANCES reaction is given by all the ortho dicarboxylic acids of the benzene series, but not the meta and para acids. Phthalyl chloride, boiling 275°, is obtained on heating the anhydride with phosphorus pentachloride. The anhydride sublimes readily in long needles, melting 128° and boiling 284°. It dissolves readily in alkalies, yielding salts of phthalic acid. On fusion with phenol in presence of zinc chloride it yields phenol- phthalein. Isophthalic acid is the meta form. It melts above 300° and when strongly heated sublimes unchanged. It is very sparingly soluble in water. Methyl isophthalate, CeEUCCOOCHs^, melts at 65°. Terephthalic acid, the para form, sublimes without melting. The methyl ester melts 140°. To prepare the methyl esters for identification the acid is warmed with phosphorus pentachloride and the clear solution poured into an excess of methyl alcohol. When the vigorous reaction has subsided, the liquid is poured into water, the separated salt collected, recrystallized, dried on a porous plate and then in vacuo. PHENOLPHTHALEIN J>C(C 6 H 4 OH) 2 This substance, which is a derivative of phthalophenone, is prepared by heating 3 parts of phthalic anhydride with 4 parts phenol and 5 parts powdered zinc chloride at 1 15-120° for eight hours. The product is washed with water, dissolved in sodium hydroxide, filtered, and phenolphthalein precipitated with acetic acid. It has attained considerable importance in medicine as a laxative and will be found alone and in combination. It occurs as a white or faintly yellow crystalline powder, melting at 250°, readily soluble in alcohol, ether, and alkalies, and slightly soluble in water. The alkaline solutions are deep pink, the acid colorless. It is removed from an acid solution by shaking with ether and will be indicated by shaking out a portion of the ether solution with ammonia. Some of the anthraquinone deriv- atives occurring in rhubarb, senna, cascara, and other laxative drugs will give a pink color under similar conditions, but these derivatives are yellow and the yellow color is imparted to the ether, while the phenolphthalein is colorless in ether. The anthraquinone derivatives dye wool a yellow color from an acid bath. The color is stripped b}^ dilute ammonia and will give a second dyeing. An alcoholic solution of these derivatives on evaporation with ORGANIC ACIDS— AROMATIC SERIES 667 ferric chloride leaves a yellow residue; phenolpkthaiein under similar condition leaves a pinkish residue with odor of phenol, the color disappear- ing on cooling or in the presence of moisture. Phenolphthalein goes onto wool, but no color is imparted, if the treated wool is dropped into dilute ammonia the characteristic pink color will appear. The separation of phenolphthalein from the anthraquinone derivatives has been described in the chapter on the Anthraquinone Drugs. Several derivatives of phenolphthalein are used in medicine, among which are the dicinnamate, diisolverate, dibutyrate, salicylate, and car- bonate. Halogen derivatives are obtained by heating phenols with halo- genated phthalic acid in presence of dehydrating agents. The product obtained from phenol and tetrachlorphthalic and melts at 316°. Tetraiodophenolphthalein or Nosoohen" (C 6 H 2 l20H) 2 C< >CO This substance, also known as Iodophen, is a light-yellow, odorless, tasteless powder insoluble in water and acids, soluble in ether, chloroform, and alkaline solution, and melting with decomposition at about 225° C. It is used as an antiseptic, sometimes being substituted for iodoform. The sodium salt is sold under the name Antinosin, and is a blue powder. It is used in a weak solution for spraying the mouth, nose, and throat in diphtheria, and for other affections of the mucous membrane. The bismuth salt is called Eudoxin. It is a reddish-brown, tasteless powder, insoluble in water, used as an intestinal antiseptic, IODONE Iodone is prepared by treating a solution of phthalic-acid anhydride in acetic ether, with a solution of iodin and potassium iodide and crys- tallizing the product from suitable solvents. It occurs in the form of dark green prismatic crystals which melt with decomposition at 163° C. When freshly prepared it is odorless, but on standing, traces of iodin are liberated, giving it a faint odor of iodin. It is gradually decomposed into phthalic acid, iodin, and potassium iodide by water, in which the decomposition products dissolve until a saturated iodin potassium iodide solution results. Any excess of iodin remaining in contact with the supernatant liquid remains unchanged. Alcohol, chloroform, and ether decompose iodone, but more slowly than water. Iodone crystals are stable in dry air; exposed to damp air, they gradually liberate iodin. 668 ORGANIC SUBSTANCES CINNAMIC ACID, C 6 H 5 CH = CHCOOH Cinnamic acid is one of the best known unsaturated acids of the aro- matic series and is of great importance in drug work. It occurs free and combined in the aromatic balsams of Peru and Tolu and in storax, and as an ester in the aloeresinotannol of Barbadoes aloes. It is prepared com- mercially from these sources, and also by heating benzaldehyde with acetic anhydride and anhydrous sodium acetate. This reaction is known as Perkin's reaction and is a general one for the preparation of unsaturated aromatic acids. C 6 H 5 CHO+CH 3 COOH = C 6 H 5 CH = CHCOOH+H 2 Cinnamic acid is employed in the treatment of tuberculosis and lupus. It is used alone and in combination with arsenic and opium and with cocain. It will be found chiefly, however, in the aromatic balsams, which are used to a large extent, and its chemistry is, therefore, intimately con- nected with these drugs. Cinnamic acid is unsaturated. It crystallizes from water in needles melting 133-135°, boils 300-304°, soluble in alcohol, ether, chloroform, and petroleum ether. It distills with steam, but does not sublime at the temperature of the water-bath. It combines directly with bromine, yielding phenyl a/3-dibrom propionic acid, CeHsCHBrCHBrCOOH. On reduction with sodium amalgam it is converted into phenylpropionie acid, melting 48-49°. When distilled with lime it is decomposed into carbon dioxide and phenyl ethylene or styrolene. C 6 H 5 CH = CHCOOH = C 6 H 5 CH = CH 2 +C0 2 Concentrated nitric acid converts it into a mixture of ortho and para- nitrocinnamic acids. The para acid is readily separated from the ortho and identified by its melting-point. Cinnamic acid when warmed with permanganate is converted in part to benzaldehyde, which is recognizable by its odor. It may be further identified by the formation of the para nitro com- pound. Stir .1 gram of the acid into 3 mils fuming nitric acid. It will dis- solve at first, but a precipitate soon appears. Add 30 mils of cold water, stir, filter, and wash with 10 mils cold water. Transfer the precipitate to a test-tube and boil with 5 mils alcohol, cool, shake, filter and wash with 5 mils cold alcohol. Boil the precipitate with 5 mils ether, cool, shake, filter and wash with 5 mils cold ether, dry precipitate at 100° and determine the melting-point of the paranitrocinnamic acid, which softens ORGANIC ACIDS— AROMATIC SERIES 669 at 270° and melts at 286-287°. Any orthonitro acid or nitrobenzoic acid formed will be removed by the alcohol and ether. It has been claimed that cinnamic acid prepared from Storax differs slightly from the synthetic acid in melting-point, and in the character of its crystalline form, but it is probable that any difference is due to small quantities of impurities. Cinnamic acid can be titrated directly by alkali by dissolving it in neutral alcohol, using phenolphthalein. When it is the only ether soluble acid present in a mixture, it can be determined by dissolving the sample in water, acidifying with dilute sul- phuric acid and shaking out with ether. The ether is washed, filtered, and evaporated at a low temperature or spontaneously and the acid titrated as above. In the case of products which do not dissolve in water, but which may be soluble in ether, the sample is treated with the solvent, filtered if necessary and the ether solution shaken several times with 10 per cent sodium bicarbonate. The alkaline liquid is then acidulated with sulphuric acid and the cinnamic acid shaken out with ether and determined. When the cinnamic acid occurs in esters, resort must be had to saponi- fication. Usually a certain amount of free acid is present at the same time and if desired, both the free and combined acid can be separately determined in one sample. The product is treated with ether and the solu- tion filtered into a separator and shaken out with bicarbonate to remove the free acid which is determined as above described. The ether solution is then treated with excess of alcoholic potash and boiled under a reflux condenser. The alcohol is finally evaporated and the residue dissolved in water, filtered into a separator, the cinnamic acid set free from the potas- sium salt with sulphuric acid, shaken out with ether and finally titrated. Sodium metaoxycyanocinnamate Zimpher C 6 Hi(OH)CH = CCNCOONa This a yellowish-white crystalline substance soluble in water and dilute alcohol. It is used in dyspepsia and in gastro-intestinal atony. TRUXILLIC ACID Truxillic acid, which is a dicinnamic acid, has been described at length under the Coca Alkaloids. Atropic Acid, CH 2 = C.C 6 H 5 — COOK. Atropic acid is obtained on boiling tropic acid for a long time with barium hydroxide. It melts 106-107°, is volatile with steam and soluble in alcohol, ether and slightly. in water. Isatropic Acids, a and 0. 670 ORGANIC SUBSTANCES These acids result on heating atropic acid. The a acid is C6H5CCOOHCH2C6H4CHCOOHCH2. It melts 237-238°. The /3-acid melts 206°. Tropic Acid, C 6 H 5 CH(CH 2 OH)COOH. Tropic acid is one of the hydrolytic products of atropin. It melts 117-118° and is soluble in alcohol, ether and hot water. HYDROXY CARBOXYLIC ACIDS There are two classes of these acids according as the OH group is in the nucleus or the side chain. In the first case they have phenolic charac- teristics, and such acids are both phenols and acids. In the second case they have alcoholic characteristics, and compounds of this class, such as mandelic acid, C6H5CHOHCOOH, have properties closely resembling those of the fatty hydroxy acids. The first class contains two acids, which are of especial importance in drug work, salicylic and gallic. The hydroxy acids of this class may be prepared from the hydrocarbons by forming the nitro-compounds and then the amido compounds, which on treatment with nitrous acid gives the hydroxy acid. They also result when the aromatic acids are sulphonated and the sulphuric acids fused with potash, the meta compounds resulting by this methocL The ortho acids result generally when a sodium phenolic compound is heated to about 200° C. in a stream of carbon dioxide. Most dihydric and trihydric phenols may be converted into the corresponding hydroxy acids by heating them with ammonium carbonate or potassium bicarbonate. Another method consists in boiling a strongly alkaline solution of a phenol with carbon tetrachloride, the ortho acid resulting in greatest amount with varying proportions of the para. .COONa C 6 H 5 ONa+CCl4+5NaOH = C 6 H4< +4NaCl+3H 2 X)H These acids are colorless crystalline solids more readily soluble in water and less volatile than the acids from which they are derived, and soluble in the ordinary organic solvents. When heated with lime they are decomposed with the formation of phenols and carbon dioxide. The ortho acids give color reactions with ferric chloride, but the m- and p-acids give no coloration. They form salts with carbonates and with the calculated quantity of caustic alkali, but when an excess of alkali is added the hydrogen of the OH group is displaced. The di-metallic salts are decomposed by ORGANIC ACIDS— AROMATIC SERIES 671 carbon dioxide with the formation of mono-metallic salts, but the metal in the carboxyl group cannot be displaced by it in this way. They yield well-defined precipitates with bromin. The ethereal salts are prepared by saturating a solution of the acid in the proper alcohol with hydrogen chloride. By this treatment only the hydrogen of the carboxyl is displaced and normal salts such as methyl salicylate are produced. These compounds still have phenolic properties and dissolve in alkalies, forming metallic derivatives such as methyl potassium salicylate, which when heated with alkyl halogens yield alkyl derivatives such as methyl methyl salicylate, C6H4(OCH 3 )COOCH3. If dialkyl compounds of this type are hydrolyzed with alcoholic potash, only the alkyl of the carboxyl group is removed. The other alkyl group is not removed even on boiling with alkalies, but when heated with hydro- chloric acid it is converted into the hydroxy acid. OCH 3 /OH C 6 H4< +HI = C 6 H4< +CH3I - x COOH x COOH SALICYLIC ACID Salicylic acid occurs widely distributed in nature in the form of its methyl ester, and this compound forms the greater part of oil of winter- green or gaultheria and oil of sweet birch. It has been prepared commer- cially from these oils and the sodium salt of the acid from this source is still preferred by some practitioners instead of that from the synthetic acid. There may have been some reason for this preference in the early days of the synthetic acid, because of the presence of objectionable impurities, but in its present high state of purity it is probable that any supposed difference is due to prejudice, and not to any inherent difference in properties. Salicylic acid and the salicylates are extensively employed in remedies for rheumatism and gout and to some extent for colds and fever. It is also used in remedies intended for local application in veterinary practice and in corn remedies. Its use as a preservative and an anti-fermentative is well known. The acid is dispensed alone or in the form of its sodium salt in pills and tablets of different strengths, and combined with morphin sulphate. It is combined with sodium bicarbonate, colchicin, and guaiac in rheu- matism tablets; with sodium sulphate, Nux Vomica, ipecac, and Capsi- cum in anti-fermentative tablets; and with astringent drugs for leucorrhea. Elrxir of Salicylic acid compound contains also Cimicifuga, Gelsemium and potassium iodide and it will be found in cough mixtures containing eriodictyon, licorice, wild cherry, potassium bromide, Grindelia, and tar. 672 ORGANIC SUBSTANCES Sodium salicylate is a component of many different tablet compounds. It will be found with acetanilid, acetphenetidin, codein, caffein, and sodium bicarbonate in remedies of the headache and cold type; also with Hyos- cyamus, camphor monobromated, acetanilid and Gelsemium for migraine ; in rheumatism mixture with colchicin, codein, and Digitalis; with aconite, belladonna, bryonia, morphin, mercuric iodide, and oil of gaultheria for follicular tonsillitis; with eucalyptol, thymol, and menthol and sodium benzoate, borate, bicarbonate, and chloride in nasal tablets; and with ginger, Capsicum, and cardamom in anti-fermentative mixtures. Sodium salicylate is used in liquid rheumatism remedies with the salicylates of potassium and Hthium and manaca, and also with colchicin. Bismuth salicylate is a basic salt used for intestinal catharrh, and will sometimes be encountered in tablet form alone, and with zinc sulpho- carbolate and aromatics. Salicylic or ortho hydroxybenzoic acid occurs in white needle-like crystals, melting 156°, subliming at the temperature of the water-bath and volatile in a current of steam. It is slightly soluble in cold water, readily on warming and dissolves in all the ordinary organic solvents. Its neutral solution gives an intense violet color with ferric chloride, it gives a precipitate of tribromphenol bromide with bromin water which on filtering, treating with sodium bisulphite and washing yields tribromphenol melting 92.5-93.5, and from a solution alkaline with soduim carbonate, a violet-red precipitate of tetraiodophenylenquinone, (CeEfe^O^, with iodin in potassium iodide. Silver nitrate and lead acetate give precipi- tates with neutral salicylates, but not with the free acid. Barium chloride does not give a precipitate. Fehling's solution is reduced by the acid. The para and meta hydroxybenzoic acids isomeric with salicylic have different melting-points and do not give the violet color with ferric chloride. The para melts 213-214° and the meta 200°. They are but sparingly solu- ble in chloroform. Alkaline solutions of salicylic acid give a precipitate of the acid when acidified with mineral acid, and on shaking with ether it is entirely dis- solved. It is partially removed from its acid solution by petroleum ether, but if the amount is large this solvent seems incapable of removing the entire quantity, even after several shake-outs. The first two or three shakings remove noticeable quantities, but after this the successive shak- ings seem to have little effect. Salicylic acid may be removed from an ether solution by shaking with sodium bicarbonate, differing in this respect from phenol and furnishing a means of separation. Para-creosotic acid is about the only acid which is likely to be found in salicylic acid, and its presence will be indicated by a lowering of the melting-point. ORGANIC ACIDS— AROMATIC SERIES 673 If .25 gram of the acid is triturated with 5 mils of water and poured into a test-tube, treated with 2 drops of 2 per cent alcoholic solution of furfuraldehyde, shaken, and then 2 to 3 mils of concentrated sulphuric acid poured carefully to the bottom of the tube, a brown zone appears if o-creosotic is present, and a violet zone if phenol or m- and p-creosotic acids are present. One gram of salicylic acid dissolved in 5 mils water and 1 mil nitric acid 1.2 sp. gr. and boiled five minutes, forms nitro salicylic acid, which may be precipitated by pouring into 20 mils water and purified by recrys- tallization from hot water. The nitro acid sinters at 220 and melts at 226°, and serves as a means of identification. Fuming nitric acid converts salicylic acid to picric acid. Salicylic acid dissolves in formaldehyde solution and on adding con- centrated sulphuric acid a precipitate is obtained, colorless at first, but becomes red and the solution magenta. A solution of salicylic acid or a salicylate treated with sodium nitrite, acetic acid, and a drop of copper sulphate and boiled gives a blood red color. Benzoic and cinnamic acid do not give this test. When carried out in the following manner Jorissen's test is stated to be considerably more delicate than the ferric chloride reaction. The solution to be tested is treated with 4 to 5 drops of 10 per cent solution of sodium or potassium nitrite, 4 to 5 drops of 50 per cent acetic acid, and 1 drop of a 1 per cent solution of copper sulphate, the liquid being shaken after the addition of each reagent. After heating in a boiling water-bath for forty-five minutes and cooling the color is examined against a white background, a blank test being carried out in a similar manner. In this way .005 to .01 mg. of salicylic acid in aqueous solution can be detected: faint but perceptible reactions are obtained with 5 to 8 mils of a 1 : 1,000,000 solution, and with 18 to 25 mils of a 1 : 3,500,000 solu- tion. The ferric chloride and Jorissen reactions may be applied to the same solution of salicylic acid, the liquid, after the addition of ferric chloride, being diluted until the violet color disappears and then sub- mitted to the Jorissen test. Benzoic, cinnamic, and tartaric acids, maltol, isomaltol, orcinol, arbutin, resorcinol, and phlorizin do not respond to the Jorissen test. A 1 : 100,000 solution of phenol gives the same color as a 1 : 1,000,000 solution of salicylic acid. With the Millon reagent phenol can be detected at a dilution of about 1 : 2,000,000. With sali- genin the limit of delicacy of the ferric chloride reaction is between 1 : 10,000 and 1 : 20,000; in the Jorissen test saligenin gives a red color at 1 : 10,000, a yellowish tint at 1 : 100,000, and no reaction at 1 : 1,000,000. 2-hydroxyisophthalic acid gives the Jorissen reaction up to a dilution of 1 : 100,000, but is easily distinguished from salicylic acid by the color 674 ORGANIC SUBSTANCES it gives with ferric chloride. Methyl-ethyl acetoacetate gives neither the Millon nor the Jorissen reaction at a dilution of 1 : 1000. The mono-metallic salts are prepared by neutralizing a hot aqueous solution with metallic carbonate and are as a rule soluble in water. The dimetallic salts are obtained by employing an excess of metallic hydroxide and, with the exception of the alkali salts, are insoluble. The dimetallic salts are decomposed by carbon dioxide with formation of the mono- metallic salts. In the general scheme of analysis salicylic acid appears first on shak- ing out the acid solution with petroleum ether, and will be indicated on testing the residue with ferric chloride. If benzoic acid is present it can be separated by precipitating the salicylic acid with bromin water and the identity of the tribromphenol established by washing, drying, and determining its melting-point. If the acid or its salt occurs alone in a product or in a mixture where it is the only substance removable from acid solution by ether, its deter- mination is simple. Tablets in sufficient quantity, usually 5 to 10, should be introduced into a separator, a little water added until they are dis- integrated, diluted, sulphuric added to render the solution distinctly acid and the salicylic acid extracted with ether, using three shakeouts. The combined ethereal solutions are then washed with water, filtered through a dry filter into a tared beaker, washing out separator and filters with more ether, and the solvent evaporated using a fan and then dried in a vacuum desiccator and weighed. Liquids should be acidified with sulphuric acid and the salicylic acid shaken out precisely as above. In some cases it is advisable to shake the acid back into an alkaline solution with dilute sodium hydroxide, and after collecting the alkali in another separator the salicylic acid is liberated by sulphuric acid, and shaking out with ether and determined as above. Salicylic acid can be titrated directly with alkali, using phenolphthalein 1 mil N/10 alkali = .0138 gram acid. In cases where the acid occurs mixed with benzoic acid, the com- bined acids should be shaken out, dried in vacuum and weighed. The residue is then dissolved in about 2 to 5 mils alcohol, diluted with dilute hydrochloric acid, bromin water added in excess, the flask stoppered and allowed to stand until the tribromphenol bromide has settled and the liquid is clear. The mixture can then be filtered through a Gooch, the excess of bromin boiled off from the filtrate and the benzoic acid shaken out with chloroform and determined, or the tribromphenol bromide in the Gooch can be washed with sodium bisulphite solution followed by water, and then dried in vacuo and weighed as tribromphenol. ORGANIC ACIDS— AROMATIC SERIES 675 DETERMINATION OF SALICYLIC ACID BY BROMIDE BROMATE METHOD DESCRIBED IN DETAIL IN THE NEW EDITION OF ALLEN The process is as follows: A known weight of the sample is dissolved in water (preferably with the aid of a little sodium hydroxide) and a volume corresponding to about .100 gram of salicylic acid diluted to about 100 mils with water in a stoppered bottle. Ten mils of hydro- chloric acid (sp. gr. 1.1) is next added (von Genersich states that it is preferable to add the salicylic acid solution to the bromate solution after the acidification of the latter), followed by a known volume (about 50 to 60 mils) of a solution containing sodium bromate and bromide, of which sufficient should be used to give about 75 per cent of bromine in excess of that entering into the reaction. 1 The bottle is closely stoppered, well shaken, and allowed to remain in the dark for at least one hour to ensure the completion of the reaction. 2 Another bottle containing an equal quantity of the bromin solution is similarly diluted and acidified, and left to stand side by side with the sample. A solution of potassium iodide (10 per cent) is next added to the contents of both bottles, and the liberated iodine titrated with a decinormal solution of sodium thiosulphate (24.827 grams of Na 2 S203+5H 2 per liter). Each 1 mil of this thiosulphate solu- tion required represents .008 gram of bromin in excess of that which has reacted with the salicylic acid, .138 gram of which cause the disappear- ance of .480 gram of free bromin, or as much as will be liberated by about 50 mils of the bromin solution. The observation of the end-point may be assisted by the use of starch paste, but it is important that this should not be added until the liquid is nearly decolorized. Hence, if a prepa- ration already containing starch is to be examined, the salicylic acid must first be extracted by alcohol or other suitable solvent, and the process applied to the solution. In the case of wine and beer, the salicylic acid should be first extracted by the use of a mixture of ether and light petro- leum, and the process applied to the aqueous liquid obtained on shaking the above solution with sodium hydroxide. A. Seidell 3 has made an exhaustive study of the determination of sali- cylates by the bromin method of Freyer 4 which is essentially the Koppes- 1 This solution is prepared by dissolving 19.5 grams of bromin ( = 6.5 mils) in about 100 mils of water containing 10 grams of sodium hydroxide. The liquid thus obtained is boiled well, and then diluted with water to 2 liters. The solution keeps indefinitely. On addition of hydrochloric acid, the whole of the bromin present is liberated accord- in to the equation : 5NaBr +NaBr0 3 +6HC1 = 6NaCl +3Br 2 +3H 2 2 A more prolonged standing is desirable when very accurate results are required. 3 J. Am. Chem. Soc, 1909, 1168; Am. Chem. Jour., 1912, 508. * Chem. Ztg., 1896, 20, 820. 676 ORGANIC SUBSTANCES chaar method, and by the iodin method of Messinger and Vortmann x and concludes that the results obtained were not satisfactory or of uncer- tain reliability. At the time of his second investigation he was engaged in evolving a satisfactory method for determining thymol, and he finally accomplished his purpose and showed further that the method was applic- able for estimating salicylic acid. The details of the method as. finally elaborated are as follows: The weighed sample of .1 to .5 gram of thymol or salicylic is placed in a 300- mil glass-stoppered bottle with 1 to 2 mils carbon tetrachloride and 100 mils water. Bromin vapor is then poured into the mixture until the color, after thorough shaking, shows that considerable excess of bromin is present. After one-half hour 5 mils of carbon bisulphide and immediate- ately thereafter 5 mils of aqueous 20 per cent potassium iodide solution are added and the liberated iodin corresponding to the free excess of bromin is titrated with .1/N thiosulphate; an additional amount of potassium iodide solution is added and if no further liberation of iodin occurs the reading on the burette is taken. Five mils of aqueous 2 per cent potassium iodate solution are then added and after thorough shaking the titration with thiosulphate is continued until the iodin color is just discharged for the second time. The completion of the reaction is tested by further addition of potassium iodide and iodate solutions. The dif- ference between the first (which should be from about 5 to 15 mils .1/N thiosulphate) and the second readings corresponds to the hydrobromic acid formed by the action of bromin on the thymol. The calculation is made on the basis of two molecules of hydrobromic acid per molecule of thymol; 1 mil .1/N thiosulphate is, therefore, equal to .0075056 gram thymol, or .006883 gram salicylic acid. W. O. Emery 2 has obtained excellent results by weighing the tetra- iodophenylenequinone obtained by precipitating a solution of salicylic acid in excess of sodium carbonate by iodin. This method may be employed in separating salicylic acid from cinnamic acid, and Emery gives in detail two procedures to be employed in working with liquid and solid headache mixtures, and these have been grouped with several others, in the chapter on acetanilid, acetphenetidin, etc. The details in so far as they apply to salicylic acid are as follows: The acid after separation from other substances by appropriate means, is manipulated into chloroform solution, and run into a 200-mil Erlenmeyer containing 10 mils water and 1 gram dry sodium carbonate, sufficient to fix all the salicylic acid present, and distilled over a small flame until the chloroform has been expelled. The aqueous solution is transferred to a liter flask, treated with 10 grams of dry sodium carbonate, and made up to the mark, 1 Ber. Chem. Ges., 1890, 23, 2753. 2 U. S. Dept. Agri. Bu. Chem., Bull. 152, 1911, 236; Ibid., Bull. 162, 1912, 195. ORGANIC ACIDS— AROMATIC SERIES 677 100-mil aliquots are transferred to 200-mil Erlenmeyers, heated nearly to boiling, 35 mils of N/5 iodine in potassium iodide added (or double this quantity of N/10 iodin) enough to ensure an excess of iodin. The mix- ture is heated on the steam-bath at nearly boiling temperature for one hour, during which time a violet-red precipitate of tetraiodophenyle- quinone (CeEfel^O^, will appear. The excess of iodin is removed by a few drops of sodium thiosulphate, and the liquid decanted through a tared Gooch, care being taken that most of the precipitate remains in the flask. The precipitate is treated with 50 mils boiling water, digested ten minutes, poured into the Gooch, and the balance of the precipitate washed out with hot water. It is then dried to constant weight at 100°. The weight of the substance multiplied by .4654 gives the amount of sodium salicylate. Sodium salicylate is the most important medicinal salt of salicylic acid. It should be readily and completely soluble in water, and on adding hydrochloric or sulphuric acid, the acid is precipitated and may be removed by ether. The acid can be determined by this method, or by the bromide- bromate or iodin methods. Some firms make a specialty of selling a product made from the acid obtained from oil of wintergreen. This is often called " Sodium Salicylate true " and other designations to distinguish it from the salt made with synthetic acid. There is no way of distinguishing between the two if they are both pure, but, if in separating the acid, it is found contaminated with cresotic acid it is evident that the synthetic product was used to make the salt. A negative test, however, signifies nothing. Some products have a suggestion of wintergreen odor, but this also is no proof that the salt was prepared from natural oil. Potassium and lithium salicylate have a limited use in medicine and basic bisumuth salicylate and basic mercury salicylate will be encountered. Didymium salicylate is called dymal. Alkaloidal salts of salicylic acid used commercially include antipyrin salicylate known as salipyrin, hexamethylenetetraamine salicylate, and phenocoll salicylate or salocoll. DERIVATIVES OF SALICYLIC ACID The ingenuity of the manufacturer of pharmaceuticals has resulted in the production of vast numbers of derivatives of salicylic acid. In this list which follows the derivatives have been divided with respect to the molecular change in the original acid. Those where the change affects the nucleus alone are placed together, those where the hydroxyl is esterified are assigned to another group, and so on. The first group consists really of substituted acids, and the chemical 678 ORGANIC SUBSTANCES properties of these are in a general way similar to those of the parent substance. The second group consists of acids possessing a free carboxyl group, but with a substituted hydroxyl. These acids are removed from their solutions in ether by caustic alkalies and bicarbonates, but are very spar- ingly soluble in water, and the aqueous solution does not give any reaction with ferric chloride until it has been boiled and cooled. The third group is made up of alcoholic esters containing the free phenolic hydroxyl of the original acid. They are all removed from their ether solution by caustic alkalies, but are not taken out by bicarbonates. The aqueous solution gives colorations with ferric chloride in the cold. When saponified with alcoholic potash they yield sodium salicylate and an alcohol. If the alcohol is volatile it can be distilled off from the alka- line solution, mixed with the ethyl alcohol of the reagent, and then sep- arated and identified. The members of the fourth group, which includes esters with phenols instead of alcohols, resemble those of the third in their actions toward alkalies and bicarbonates. They are much less soluble in water, and on hydrolysis with alcoholic potash yield salicylic acid and a phenolic com- pound. The alkaline solution may be evaporated until the alcohol has been driven off and then the residue transferred to a separator, acidified, and shaken with ether, which will dissolve both the salicylic acid and the phenol; on separating the solvent and shaking it first with sodium bicar- bonate solution and then with sodium hydroxide, the acid will pass into the bicarbonate and the phenol into the alkali. The two alkaline solu- tions can then be acidified separately and the acid and phenol shaken out with ether and obtained in a condition for identification. The fifth group is relatively small and contains those substances in which both the hydroxyl and the carboxyl groups are esterified. They are of course indifferent to either caustic alkali or sodium bicarbonate when dissolved in ether, and are thus readily differentiated from any of the preceding substances. When hydrolyzed with alcoholic potash they yields acids, alcohols, and phenols depending on their composition, and which may be detected as described in the preceding paragraphs. ORGANIC ACIDS— AROMATIC SERIES 679 "c3 (3 JO "3 43 >> t 00 a 3 d c3 d 00 "♦« CD '■+3 3 CO _d 00 43 ^ ■5 OJ .2 CO 00 a o "o T3 O ft o> .2 1.2 03-_j3 OJ 03 ci ft S3 43 O T3 O 0) . 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O go a d E d cu II «s c c >> "3 43 o d c3 X s c3 OJ £ 10 a a 03 W a X S a 2 Z O w a 13 O 1 iO • oj O O a B S> "d 6 i-, o fe a O O a 6 a c ' g a 3 a oc O ^ J, J, j, N C ^O 1— 1 "0 X M a a a a a f a a 6 c d 6 6 C 6 6 3 oj oj OJ c3 .3 a) 2 >» "el c3 c 00 a g 3 15 3 d^ c3 CJ '3 c3 'S c3 c3 03 73 'E 1 2*1 "3 CJ 00 O 00 TS GO c "r O .2 'd 43 ft 1— 1 T3 o 'o a 03 O ^ Sl3 2 "c3 01 O T3 a _3 T5 % 43 la 2 2 3° a .a or E c "2 "c3 3 ^ la 00 a .a o x 01 — s p X OJ 43 2 5" c X r a < '3 X C 680 ORGANIC SUBSTANCES M s a '■£ p < » .2 >> Si ft M '43 "a G c c3 ri '■+3 G 03 "53 •Jj .2 t ft -S 02 _ i G •S .2 II P. 02 C3 -G Q u Antirheumatic, antipyretic, analgesic 09 3 '■S3 02 No color at first, gradu- all y on standing 09 3 £ ■ 3 m o 3 3 02 03 ft 02 3 o o en So 0) 3 3 GO 02 3 3 CO >> to 02 U O > 11 53 tf 3 02 .2 03 o a «1 3 j2 3 02 03 ft CO 3 02 53 o IO CO 1 o o 00 CO o IO o o O OS' o o> 00 "ft 02 < 1 eS O CI .2 's-< ■ft 02 03 Q _G ■ft 02 03 O .J 02 09 o3 SI G 02 pq J 1 03 o3 02 S Ph w o o o 6 w d o w d R o o g d— o x o — d w g ° 2 o o BOW d /\ d ' 8§ 88 o o - o w \/ w o — o — o o tasS o w o O fc o N/ d w o a8w o w o O 55 O N/ d 'ft B "> c < e -a l > & 3 "§ o3 ^ * Sis ^3 ft g -J &■§ 'I g 2 -S 03 SI 73 .S «j g o GO 73 o3 o "£> "oS 02 73 ■>> .2 '3 o '3 c3 o ■>> o r e8 02 I s 0) ,G ■s o ■>> o 02 % 02 fi 1 o 73 "la 1 § << 3 03 .2 ■>> la 02 ">. 02 6 73 1 02 o < ORGANIC ACIDS— AROMATIC SERIES 681 +3 C 03 0) 3 ft ft OJ .2 03 a 3 S 0} CO 0J P -2 -13 "3 0) OQ a C 03 J3 03 a a 0) -a » - TZ O 03 .2 a 3 03 03 •43 a 03 '-^ 11 o3 C o3 "§ •H* |S ■43 s 3 _o S a 2 « A a ft -£ -js ,4 • rt ft a S .2 .22 .53 T3 •_j3 CC 13 a a B C 03 a a a <«! < < «! •< < < w « o> ,Q ,Q x> a a 3 O m w Ul ^ CO a £1 ,2 3 >) a J2 43 ~ CD O a .a c O a be a QQ m 53 5! N so CO pq O a "3 a t> . 7 9 a CT> H cq O 00 ^j a =g * a I> ~ iH rH a s 41 O 13 g TJ ^ a £ a O w * o .g *H - oo X ft w n W H w rt u o « a m 3 a a .2 * 03 >> M a 03 >> >> O e3 02 £s "ea ■£ ,2 14 & < 682 ORGANIC SUBSTANCES OQ 1 -J- c a = cc ■ Is Hi >> .2* fl C3 ft to .2 3 CD > .& C3 _o ft .2 fl C3 o ^ '43 03 c3 •1 ^ »i c ~ Intestinal antiseptic, anti- rheumatic ,2 3 -2 ^fl 3 DQ 3 02 j>> -fl CQ -2 3 j3 3 CQ r2 3 ^3 3 CQ CD 3 3 CO CD 3 _a 3 CQ -2 3 3 CQ 3 a 3 CQ -2 3 CQ -2 3 j3 3 m 3 CQ CO CD 3 j3 3 CQ 3 3 CQ -2 3 3 CQ -2 3 3 CQ 0) 3 3 CQ 3 DO >> u >> 3 Pi CD ,2 3 3 03 CI 4) 3 fl 3 CD fl 03 3 js 3 cq fl 3 CQ CQ 3 3 CQ fl 3 ^3 3 ca C CD 3 CQ c HH o 1> co T CO CO 00 33 S C 3 13 CQ CQ 3 EG 3 13 CQ o o a o -fl ft o 3 CQ 3 O O 3 'c — ■ 1 8 3 » 5 § 3 g >> 3 CQ 3 3 CQ 3 o ca 3 a O 3 .2 13 OS 3> fl O rfl ft o 3 Q 3> c « ft o 1 03 ft -2 3 *>> 3> -^ o < r Cf E C - CD cc 3 aT as 3> o 3 CQ CQ 6 ° 3 CD 3 >, .2 3 r-t CQ c > c 1 DC 3 > c > c ~ a 3 c B 'S 3 c a 4- T > e 1 a "c D c c, c 1 CD 3 % .2 3 CQ 3 -a 3. ft c3 fl =5 o 3 % .2 3 CQ 3 -A 3 a c3 C e3 4> « \ \ ORGANIC ACIDS— AROMATIC SERIES 683 ESTERS INVOLVING BOTH OH GROUPS, AND THEIR DERIVATIONS /O(X) C 6 H 4 <( X COO(X!) Acetyl methyl salicylate. . . . /OCOCH3 X COOCH 3 Methyl Aspirin 54° Insol. Sol. Sol. Antineuralgic Methyl benzoyl salicylate. . . . c 6 h/ x coo(c 6 h 3 co) Benzosalin 85° Sol. Intestinal anti- septic. Acetyl phenyl salicylate. . . . /OCOCHs X COOC 6 H 5 Vesipyrine Acetyl Salol 97° Insol. Sol. MISCELLANEOUS Salicyl-a- § methyl phenyl-hy- drazone. . . Salicyl-quinin. C 6 H 8 CH»N • N • CH • CeH^OH C 6 H,OHCOOC2oHaN20 Agathin 74 c Cosmin Saloquinine 130' Insol. Insol. Sol. Sol. Sol. Sol Antirheumatic, antineuralgic Antineuralgic, antiperiodic, analgesic, febrifuge Salicyl quinirt salicylate. . . Condensation product of salicylic and gallic acids. . C 6 H 4 OH, COOCOC 6 H 2 (OH).i Salitannol 210° SI. sol. Insol. Spar. Sol. Antineuralgic, antirheumatic Insol. Substitute for salol Condensation product of salicylic and boric acids. . (CcHiOCOOH) 2 BOH Borosalicylic acid Antiseptic Phenyl Salicylate C 6 H40HCOOC 6 H5 Salol Salol is used as an intestinal antiseptic and occurs alone in tablets and in powders and mixed with bismuth subnitrate, subcarbonate and subgallate, calomel, sodium bicarbonate, zinc sulphocarbolate, and pepsin. It is employed in typhoid fever and in some forms of dyspepsia and 684 ORGANIC SUBSTANCES bowel trouble, as chronic constipation. It is often dispensed with acet- anilid, acetphenetidin, lactophenin, and other anilides and phenetidins. It is a compound of many gonorrhea mixtures with sandalwood oil, copaiba, oleoresin of cubeb, and pepsin. It is sometimes used externally as an antiseptic for sores and wounds. Salol is a white crystalline powder with a faint phenolic odor, melting 42-43° C, almost insoluble in water, soluble in alcohol, ether, chloroform, fixed and volatile oils. Its solution in alcohol gives a violet color when treated with dilute ferric chloride, but if a few drops of the alcohol solu- tion is added to 10 mils of dilute ferric chloride, a white cloudiness, but no color, will be produced on shaking. When warmed with sodium hydroxide it is hydrolyzed, and on diluting with water and acidulating, salicylic acid separates and the odor of phenol will be apparent. The two components can then be readily separated and identified. Salol can be removed from a solution of ether or chloroform by fixed alkali, and this property furnishes a ready means of separating it from acetphenetidin and other antypyretics with which it commonly occurs. In order to establish its identity in a mixture of oils, the sample is dissolved in ether, shaken with acid to remove basic constituents, and then extracted with potassium or sodium hydroxide, which will remove the salol. The latter can then be recovered by acidulating and shaking out with ether. If any fatty acids are removed at the same time they can usually be separated from the salol, by shaking the ether solution with sodium bicarbonate, which does not remove the salol. • In order to estimate salol in a mixture of copaiba and other oils, the sample is dissolved in ether, and extracted three times with 2J per cent sodium hydroxide. The alkaline solution is brought to the temperature of the steam-bath and held for five to ten minutes, and the balance of the determination conducted according to the following process: C. C. LeFebvre x has applied the bromin method to the determination of salol in tablets and powders: First extract the salol from a weighed portion of the powdered sample by means of 50 mils ether. In order to prevent moisture from collecting on the paper, use a short extraction thimble in an ordinary extraction tube, the ether being introduced by means of a separatory funnel, the stem of which passes through a stopper in the end of the tube. Run the sol- vent into a flask and remove the solvent by air blast. Then add 10 mils 2| per cent sodium hydroxide and heat for five minutes at the temperature of the steam-bath. After this is complete dilute the alkaline liquid to about 200 mils, add an excess of potassium-bromide bromate solution, followed by 10 mils of concentrated hydrochloric acid. Shake the mix- ture for a minute, and then frequently during a half hour. At the end 1 U. S. Dept. Agri. Bu. Chem. Bull. 162, p. 203. ORGANIC ACIDS— AROMATIC SERIES 685 of this time add 10 mils of a 15 per cent potassium-iodide solution, and frequently agitate the mixture while it reacts for fifteen minutes. Titrate the free iodin with the thiosulphate solution which has been standardized against the bromin solution. From the number of cubic centimeters of the bromin solution expended, calculate the salol on the basis of 12 atoms of bromin to 1 molecule of salol. A few determinations made, where various excipients were added to the salol before saponification and allowed to remain throughout the titration, indicate that none of them except lactose interferes to any considerable degree. Even in this case, the quantity usually present would not throw the result off more than a few per cent. Tragacanth, Indian gum, acacia, lactose, starch, and dextrin were tried. This would seem to show that the method may be carried out directly on salol in the tablet, without previous extraction with ether. The reactions involved are the following: First, the salol is saponified to sodium or potassium salicylate and phenolate : HOCeHiCO • OC 6 H 5 +3KOH = KOCerLtCO • OK+C 6 H 5 OK+2H 2 Phenol is attacked by bromin in excess to form symmetrical tribromo- phenolbromid : C 6 H 5 OH+4Br 2 = C 6 H 2 Br 3 OBr+4HBr Salicylic a.cid also forms the same product, inasmuch as the tribromo- salicyiic acid first formed is very unstable and loses its carboxyl : C 6 H 2 Br 3 OBr+2HI = C 6 H 2 Br 3 OH+HBr+I 2 As a result, 12 atoms of bromide have been used up by 1 molecule of salol. The procedure for assaying mixtures of acetphenetidin and salol is described on page 859. Acetyl paramino phenylsalicylate CelLtOH • COOC6H4NHC.OCH3 Salophen It forms small, white, crystalline leaflets or powder, odorless and taste- less, melting at 187 to 188° C, and containing 51 per cent of salicylic acid. It is almost insoluble in cold water, more soluble in warm water, but freely soluble in watery solutions of the alkalies and in alcohol, ether, and benzene, but not in petroleum benzine. If its alkaline solution be boiled it gradually becomes blue; on con- tinuing the boiling the color is discharged, but is again produced on cooling 686 ORGANIC SUBSTANCES and exposure to air. On addition of ferric chloride to the alkaline solu- tion the violet color characteristic of salicylic acid is produced, but a simple aqueous solution of salophen does not react with ferric chloride and should not be changed by silver nitrate. Acetyl salicylic acid .OCOCHs CeH4< COOH Aspirin Aspirin forms small, colorless, crystalline needles, melting at 129-130°, odorless, and having an acidulous taste. It is soluble in 100 parts of water and freely soluble in alcohol, ether, chloroform, and glacial acetic acid. It is readily split up on boiling with water or with alkalies with the pro- duction of acetic acid and salicylic acid or a salicylate. It forms clear, colorless solutions with water, which do not develop a violet color on the addition of ferric chloride unless previously boiled or hydrolyzed by boiling with sodium hydroxide, or unless it stands for some time in the presence of cold water. It gives no reaction with silver nitrate, and should leave no residue when heated on platinum foil. When added to boiling water the odor of acetic acid is easily dis- tinguished. Acetyl salicylic acid may be removed from chloroform with alkalies and by sodium bicarbonate. If the former is used there may be a certain amount of hydrolysis and free salicylic acid results, but with bicarbonate in ice-cold solution the hydrolysis can be kept down to a minimum. Acetyl salicylic acid does not give a precipitate with bromin water, hence it is easy to detect the presence of free salicylic acid. Dissolve in alcohol, add a few drops hydrochloric acid, then bromin water until a permanent yellow color is obtained. If salicylic is present, the color of bromin will disappear at first, but no color will appear until dilution has reached a certain degree and finally the color of bromin persists and a precipitate agglomerates and settles. If acetyl salicylic is alone present, the color due to bromin does not disappear and no precipitate appears on dilution. Astruc finds that acetyl salicylic acid can be titrated accurately in dilute alcoholic solutions with potassium hydroxide and phenolphthalein without splitting off any of the acetyl group. From the acid number and saponification number the quality of commercial samples can be deter- mined. Dr. Emery found that aspirin of 100 per cent purity softened at 129.5° C. and melted from that temperature up to 130°. Mixtures of the pure substance with salicylic acid showed a tendency to soften several degrees ORGANIC ACIDS— AROMATIC SERIES 687 below the melting-point, in some cases 10-20°, the material then remain- ing in a more or less pasty condition until the point of complete fusion is reached, which in the case of mixtures containing 60-85 per cent of salicylic acid extends over about 10°, the acid not dissolving readily in the melt, but remaining in solid form at the bottom and sides of the capillary. A mixture containing 58 per cent of aspirin melts sharply 115-116°, indicat- ing an eutectic mixture of about that composition. The estimation of free salicylic acid in acetyl salicylic acid may be accomplished by dissolving .1 gram of the sample in 1 mil of alcohol, followed by 48 mils of water and 1 mil of ferric chloride solution (1 volume of test solution U. S. P. to 100 volumes of water). The color is then matched against that produced by known amounts of a standard solution of sodium salicylate (.116 gram to 1 liter) made up to the same volume, and using the same quantity of reagent, Methyl Salicylate, C 6 H 4 OHCOOCH3 Methyl salicylate is an exceptionally interesting substance, both on account of its varied uses, and the anomalous commerical conditions relating to it. It is used to a large extent as a flavoring agent, as an anti- septic and as an antirheumatic. In the trade it is sold under three names with widely divergent prices, depending on the designation. Methyl salicylate is widely distributed in nature, but is especially prominent in the leaves and the fruit of the wintergreen (Gaultheria procumbens) and in the stems and bark of the sweet birch (Betula lenta). also occurs in senega root (Polygala senega), Gaultheria punctata, and G. leucoceupa, and in small quantities in other plants. It probably is combined with other substances in the plant, but in a state where it is readily set free by the action of ferments, heat or water. The pleasant taste of the wintergreen plant probably first suggested its use in the form of an extract or essence for flavoring purposes, and, as the commerce grew and with it a demand for a purer product, the highly rectified oil containing the essential flavoring agent was gradually evolved. Owing to the increasing demand for the oil, and the comparatively limited amount of the plant, the hunt for other sources of crude material was started, and the oil distilled from sweet birch came into the trade. Finally the chemical composition of the oil was established as methyl salicylate, and after synthetic salicylic acid came to be a commercial possibility, it was but another step to prepare the methyl ester, and the latter is now made in a large way. After salicylic acid was found to have a physiological and therapeutic importance, the medical profession seemed to prefer the natural product to the synthetic, but later, when processes of manufacture became more 688 ORGANIC SUBSTANCES refined and no chemical difference existed between the two, this prejudice began to wane. The oil prepared from wintergreen and rectified contains a small quantity of a mixture of substances which appear to give it a shade of flavor differing slightly from the ester made directly from salicylic acid, and the same possibly applies to the oil from birch, though to a much less extent. The condition as regards the flavor is probably analogous to that existing between what is known as straight and rectified whisky. Chemically, these three products are practically the same, the wintergreen oil being the less pure. The anomalous condition is manifested forcibly in the price, for wintergreen sells for $6 to $7 per pound, birch for $5.50 to $6, and the synthetic for about $0.65 to $0.70. In the trade the following classifications are in vogue: oil of winter- green leaf, oil gaultheria prepared from Gaultheria procumbens and now practically off the market: oil betula, oil of wintergreen from Betula lent a: methyl salicylate, synthetic or artificial oil of wintergreen. In a chemical sense, all of these terms are practically synonymous, and in the last edition of the Pharmacopoeia they are all grouped together under the one heading Methyl Salicylate. Some oils will be encountered having a red color, which has been attributed to iron, but it is doubtful if that metal is responsible for the coloration. If a red oil is dissolved in ether and shaken with dilute potas- sium hydroxide and the resultant alkaline solution neutralized, a colorless oil will be obtained. It is probable that the color is due to the same cause which produces a pink tint in phenol when it has stood for some time and which has been conclusively proven to be due to other causes than iron. Power and Kleber investigated the oils of gaultheria and betula, with special reference to the products other than methyl salicylate. They found that Gaultheria contained 99 per cent of the ester, and Betula 99.8 per cent. In order to obtain the impurities, the oil was dissolved in ether and shaken with 7.5 per cent aqueous solution of potassium hydroxide to remove the methyl salicylate, leaving the other constituents in the ether. From gaultheria, these constituents were obtained as a semi-solid mass consisting of a paraffin melting 65.5°; an aldehyde or ketone with an odor like oenanthic aldehyde; a secondary alcohol (CgHieO) boiling 160-165°; and an ester which on saponification yielded the above alcohol, and an acid, C6H10O2. The alcohol and ester possessed the penetrating character- istic odor which gives the peculiar shade of aroma to Gaultheria oil. From Betula the same constituents minus the secondary alcohol were isolated. The author had occasion at one time to study the problem of differenti- ating between the three products, and he came to the conclusion that there was practically no chemical method which would enable the analyst ORGANIC ACIDS— AROMATIC SERIES 689 to assert beyond question that there was any difference. An empirical procedure was used as a makeshift, on account of the practical problem which developed from the use of the oils in which the sample was treated with an excess of sodium hydroxide and left overnight in a stoppered flask. If the odor noticeable was then of a peculiar musty character, the product was deemed to be natural oil, or at least to contain some of the natural product. At one time there was communicated to me by the Bureau of Chemistry a method of differentiation based on the color given by mixing oil with vanillin and sulphuric acid. It is directed to dissolve 7 drops of the oil in 10 mils of a 5 per cent alcoholic solution of vanillin, and on the addi- tion of 1 mil concentrated sulphuric acid, a dark red color appears in the case of oil of Gaultheria, changing to blue on the addition of 2 volumes of alcohol. Methyl salicylate gives a yellow color. I have tried this method with commercial oils and artificial methyl salicylate, and have found that they all react in the same way, all giving the final blue color, changing to a purplish brown after twenty-four hours. Later I experimented with samples of Betula oil according to the procedure of Power and Kleber, and, after recovering that portion of the oil which was not removed by alkali from ether, I tested it according to the vanillin reaction and obtained the same blue color, which in this case was very deep and did not change to purplish brown for several days. It is evident that the color-producing material exists in the impurities, and, from further work done, that it is an unsaponifiable constituent. For assaying methyl salicylate, the following methods are recommended as giving reliable results. U. S. P. Assay Method. — Introduce about 2 mils methyl salicylate into a tared flask. Note the exact weight, add 50 mils of half-normal alcoholic potash, connect the flask with a reflux condenser, and heat the mixture on the water-bath during two hours. Then add a few drops of phenolphthalein and titrate the excess of alkali with half-normal hydro- chloric acid. Each mil of N/2 alcoholic potash consumed corresponds to .07603 gram methyl salicylate. Assay of Methyl Salicylate. — Weigh 1 gram in a closed weighing-tube, and transfer to a 100-mil graduated flask, washing out the weighing tube with alcohol, add 20 mils sodium hydroxide 10 per cent and heat to boiling for two hours. Cool and make up to 100 mils. Remove an aliquot of 10 mils, evaporate any alcohol, transfer to 200-mil Erlenmeyer, add a slight excess of hydrochloric acid, then 1 gram anhydrous sodium car- bonate, 100 mils water, and heat nearly to boiling. Add 35 to 50 mils N/5 iodin (approx. standard), digest on steam-bath for one hour, adding iodin from time to time, if necessary Then add a few drops sodium 690 ORGANIC SUBSTANCES thiosulphate to destroy the excess of iodin, decant liquid on a tared Gooch, digest precipitate in flask with 5 mils hot water for ten minutes, filter, and wash with hot water, using about 150 mils. Dry and weigh. Weight X .4658 X .95 X 10 = weight of methyl salicylate. When methyl salicylate occurs in admixtures with other substance of a volatile nature, its determination will depend largely on the nature of the combination. If the other substances are saponifiable to acids capable of ready separation from salicylic acid, the problem is not difficult. If the sample under examination is a liquid, a measured quantity is transferred to a separator, diluted with water, sodium chloride added, and the soluble oils shaken out with petroleum ether. The solvent, after washing with saturated salt solution is poured into a mixture of alcoholic potash or soda and heated under a reflux for one hour. The alcohol is then removed by evaporation, and the salicylic acid recovered from the alkaline liquid and either weighed or titrated. The methyl salicylate can then be calculated. If other acids are present at this stage, they can be separated by the procedures given under the discussion of salicylic acid. If the methyl salicylate and salicylic acid occur together in the same mixture, a chloroformic or ethereal solution of the two should be shaken with dilute sodium bicarbonate to remove the acid before attempting to determine the ester. For the determination of methyl salicylate in flavoring extracts or in spirit of gaultheria, the method of Hortvet and West 1 will be found to give good results. Measure 10 mils of the extract into a 100-mil beaker, add 10 mils of 10 per cent potassium hydroxide solution, and heat the mixture over a boiling water-bath until the odor of oil of wintergreen has disappeared and the liquid is reduced to about one-half its original volume. By this treatment the methyl salicylate is converted into the potassium salt. Liberate the salicylic acid by the addition of an excess of 10 per cent hydrochloric acid, cool, and extract in a separatory funnel with three por- tions of 40, 30, and 20 mils of ether respectively. Pour the combined ether extracts through a dry filter into a weighed dish, wash the filter with 10 mils of ether, evaporate filtrate and washings slowly at 50° C, dry one hour in a desiccator, and weigh. The per cent of wintergreen oil by volume (M) is obtainable from the weight of salicylic acid (S) by the following formula; 1.101X10XS 1.18 1 J. Ind. Eng. Chem., 1, 1909, 90. ORGANIC ACIDS— AROMATIC SERIES DERIVATIONS OF HYDROXY BENZOIC ACIDS 691 Methyl p-amido m- hydroxy benzpate . . . /OH 3 CgH/-NH 2 4 \COOCH 3 1 Orthoform 120° Spar. sol. Antiseptic, local anes- thetic Sodium Salt of Methyl p-amido m-hydroxy- benzo-sulphonate. . . C7H30 3 (S0 5 Na)(NH2) (CH 3 )+H20 Sulphonated Orthoform 269° Readily sol. Methyl m-amido-p- hydroxy benzoate . . . /COOCH3 1 C 6 H 3 (-OH 4 \NH 2 3 New Orthoform 142° Somewhat sol. Antiseptic, local anes- thetic These substances are derivatives of the acids isomeric with salicylic acid. Their properties have been fully described in the chapter on Anes- thetics. COUMARIC ACIDS, C 6 H 4 (OH)CH = CHCOOH Three forms, known as 1-2,1-3, 1^. The 1-2 form occurs in the leaves of species of Melilotus, sweet clover, and in Angraecum fragrans. It forms colorless crystals, melting 208°, with decomposition. It is freely soluble in water and alcohol, and gives a flourescent solution with alkalies. This acid is converted to salicylic and acetic acids on fusion with potassium hydroxide, but on boiling in alkaline solution it is converted to coumarin. Nascent hydrogen converts it to melilotic acid. The 1-A acid occurs as an ester in Cape aloes, in the resin of Picea vulgaris, and is one of the products of hydrolysis of naringin, Coumarin, C 6 H 4 OCOCH = CH Coumarin or " Tonka-bean camphor " occurs in Tonka, the seed of several species of Dipteryx, also in the leaves of Liatris odoratissium and those of several other plants. It forms colorless crystals, melting 67°, with an odor suggestive of vanillin, but nevertheless highly distinctive, recalling freshly mown sweet grass. It is sparingly soluble in cold water, somewhat in cold alcohol, not readily in hot alcohol and in ether. It is readily distinguished from vanillin as it is not removed from an ethereal solution by caustic alkali. Melilotic Acid, C 6 H 4 (OH)CH 2 COOH Melilotic acid is 1-2 hydrocoumaric acid, and its close relationship is readily noted by a glance at the formula. It is present with coumarin 692 ORGANIC SUBSTANCES in Melilotus officinalis — sweet clover. It melts 82 to 83°, gives a bluish color with ferric chloride, yields acetic and salicylic acids on fusion with yCH2 — CH2 potash, and hydrocoumarin CqH4\ on distillation. X)CO FERULIC ACID, C 6 H 3 (OH)(OCH 3 )CH = CHCOOH Ferulic or m-methoxy-p-hydroxycinnamic acid occurs in several resins including opoponax and asafetida. It may be obtained from the latter by treating the alcoholic solution with alcoholic lead acetate which pre- cipitates the lead ferulate. The lead salt may then be decomposed with dilute sulphuric acid, and the regenerated acid crystallized out of hot alcohol. It reduces Fehling's solution and gives a brownish precipitate with ferric chloride, which must not be confused with the buff-colored pre- cipitate obtained with benzoate. TOLUIC ACID DERIVATIVES Betanaphthol-Hydroxytoluic Acid C 6 H3(OH)(COOH)(CH 2 C 10 H 6 OH) 2:3:1 Epicarin It forms colorless or yellowish needles, melting at 190 to 195° C, difficultly soluble in water, but easily soluble in alcohol, ether, acetone, and in soaps. It dissolves in oils on the addition of a little ether. It has the character of a strong acid, forming well-crystallized salts, which, however, are sparingly soluble in water, particularly the sodium salt. On exposure to air it acquires a reddish color due to oxidation; if it is then recrystalhzed from glacial acetic acid, colorless crystals are again obtained which melt at 166° C. These, however, retain a little acetic acid, but lose this by heating at 120° C. The alcoholic solution of epicarin develops an intense blue color with ferric chloride. When heated with concentrated sulphuric acid, a red- brown solution, having a vivid green flourescence, is produced. If shaken with chloroform and solution of potassium hydroxide, a yellowish color, changing later to yellowish green is developed, thus distinguishing epicarin from beta-naphthol, which produces a deep blue color under the same conditions. Epicarin is an antiseptic and parasiticide, and is used in the treatment of skin diseases, particularly scabies, and eczema. ORGANIC ACIDS— AROMATIC SERIES 693 Protocatechuic Acid This acid occurs to some extent naturally both in the free state and in combination. It is obtained on fusing or saponifying some of the resins such as catechu, gum benzoin, gum kino, etc. It forms needle-like crys- tals melting 195-199°, readily soluble in water, alcohol, ether, and petro- leum ether. Its aqueous solution gives a green color with ferric chloride changing to blue and dark red on adding veiy dilute sodium carbonate. A neutral solution of a protocatechuate gives a violet color with ferric chloride which might be mistaken for the salicylate reactions. Proto- catechuic acid gives a precipitate with lead acetate and reduces silver- nitrate on warming. GALLIC ACID Gallic or pyrogallol carboxylic acid, C 6 H 2 fOH)3COOH 1.2.3.5, is a trihydroxybenzoic acid. It occurs in gall nuts and various vegetable products and is prepared by boiling tannic acid with a dilute acid. It crystallizes in needles with 1 mol. water which melt with decomposition at 220°, pyrogallic acid and carbon dioxide being obtained. It dissolves in water, alcohol, ether, chloroform, and etlryl acetate and its aqueous solu- tion gives a bluish-black color or precipitate, with ferric chloride soluble in excess of the reagent to a green color. The exact color is affected by the concentration of the solution and often the green tint will be the only one obtained due to the small quantity of the sample. It is a strong reducing agent and precipitates gold, silver, and platinum from solutions of their salts. Gallic acid can be removed from its aqueous acid solution by ether, thus differing sharply from tannic acid. Gallic acid is used in medicine as an antiseptic and hemostatic. It will be found in foot powders and tablets, in pile remedies, in certain gonorrhea mixtures, and in internal remedies for intestinal hemorrhage, night sweats, hematuria, pyrosis, etc. It is combined with opium and Hydrastis in menorrhagic tablets. On adding calcium hydroxide solution to a cold concentrated solution of gallic acid, a bluish-white precipitate will form where the test solution is temporarily in excess and will disappear on shaking. When the reagent has been added in excess the precipitate no longer dissolves, and the liquid acquires a tint which is blue by reflected and green by transmitted light, and becomes pink on the addition of a large excess. With tannic acid the precipitate first formed is pale bluish white and does not dissolve on shaking. It deepens in color when an excess has been added and the solution becomes pinkish with a large excess. 694 ORGANIC SUBSTANCES Gallic acid gives no precipitate with gelatin, alb" min or the common alkaloids, differing in all these particulars from tannic acid. Gallic acid is not precipitated from solution by bromin water nor by bromide-bromate reagent. With dilute hydrochloric acid and formal- dehyde no precipitate appears at first, but on standing it comes down. Tannic acid reacts in the same way. Gallic acid gives a light-yellow precipitate with lead acetate. Neither acid can be titrated with alkali. Though it gives no precipitate with bromin, there is some reaction in solution for on subsequently recovering the acid product with ether, it no longer gives the characteristic color with ferric chloride. GALLOGEN C 6 H(OH) 2 CO O C 6 (OH) 2 -COOH Ellagic Acid is anhydrous ellagic acid prepared from Divi-divi, the pods of Caesalpina coriaria. It is a yellowish, odorless, tasteless powder, insoluble in all acid and neutral liquids, but soluble in alkaline liquids to the amount of 2 per cent, such solutions being, however, very readily oxidized. Its solutions in alkaline media give all the reactions of tannic acid with iron salts, gelatin solution, etc. With fmning nitric acid it gives a* characteristic dark red color. Gallogen is an astringent and antidiarrhetic and is used in dysentery, cholera infantum, and diarrhea. Bismuth subgallate, sometimes called " Dermatol," is a yellowish powder of somewhat variable composition and may yield from 52 to 57 per cent Bi2C>3 on ignition. It is insoluble in water, alcohol, and ether, but is readily soluble in hot mineral acids and alkali hydroxides, forming with the latter a clear yellow solution rapidly turning red. If the salt is agitated with hydrogen sulphide water, a black precipi- tate of bismuth sulphide is obtained, and on filtering and boiling off the excess of hydrogen sulphide from the filtrate, the cooled liquid will give a blue-black color with ferric chloride. Aluminum gallate, known as Gallal, is soluble in ammonia. Bismuth oxyiodomethyl gallate or iodogallicin is a dark-gray powder used as a substitute for iodoform. ORGANIC ACIDS— AROMATIC SERIES 695 Galloformin This substance is a reaction product of gallic acid and hexamethylene tetramine. It is slightly soluble in water, alcohol, ether, and glycerin, and is decomposed by heat. It is used as an antiseptic. Gallanilide or Gallanol, C 6 H 5 NHCOC 6 H 2 (OH) 3 +2H20 Gallanol is a brownish crystalline powder, melting 205° C, soluble in alcohol, ether, and boiling water, insoluble in chloroform and benzol. It is employed externally as an antiseptic and astringent. Gallicin, or Methyl Gallate This substance is a grayish- white crystalline powder, melting 202°, soluble in alcohol, ether, and hot water. It is used in eye and throat troubles to relieve inflammation and congestion. Gallobromol, C 6 Bi 2 (OH) 3 COOH Dibromogallic acid is a light-brown powder, melting 140-150° C, sol- uble in alcohol, ether, and water. It is used internally as a substitute for potassium bromide and externally as an astringent and antiseptic. Gallotannic Acid This acid is probably the anhydride of gallic acid, as it is resolved into the latter by boiling with dilute sulphuric acid. Ci 4 Hio09+H20 = 2C 7 H 6 05 The pure acid is an almost colorless amorphous substance which dis- solves readily in water, alcohol, and glycerin, somewhat soluble in ethyl acetate, and almost insoluble in ether and chloroform. It is removed from its acid aqueous solution to a very slight extent by ether, but is taken up gradually by ethyl acetate, especially if the solution is saturated with salt. Its aqueous solution gives a blue-black precipitate with ferric chloride, with most alkaloids including cinchonin, and with gelatin. It is completely precipitated by lead acetate, and this property furnishes a means for its quantitative estimation. It is also removed from its aqueous solution by hide powder and by this means can be separated from citric or tartaric acids. Tannic acid is used for the same purposes as gallic acid and is valuable in chronic diarrhea and as an antidote in alkaloidal poisoning. It is used 696 ORGANIC SUBSTANCES to a considerable extent in pile remedies, where it is combined with opium, camphor, menthol, boric acid, etc. Combined with glycerin it forms an efficient gargle for sore throat. Iodotannic acid used in gonorrheal injec- tions consists of an alcoholic solution of tannic acid and iodin. The commercial acid is often impure, containing varying amounts of foreign or transformation products insoluble in water. In order to determine tannic or gallic acids a procedure based on that recommended by the writer for tea may be advantageously employed. Lead tannates contain definite quantities of lead, and if a solution contain- ing the acid is precipitated by a known quantity of lead acetate in excess, and the lead remaining in solution determined, it is a simple matter to arrive at the amount of tannic acid. To carry out this procedure properly one must know the lead content of the tannate yielded by the drug in question, and this will naturally require a certain amount of research, for it will first be necessary to prepare the tannin in the pure condition. In the case of tea tannin the lead content is 48.3 per cent. The following method will enable one to obtain a very accurate esti- mation of the quantity of tannic acid in tea: Ten grams of powdered tea are transferred to an Erlenmeyer of 100- mils capacity, 50 mils petroleum ether added, stoppered, and shaken occasionally and allowed to stand overnight. It is then filtered through a dry filter and the flask and filter washed with petroleum ether until the filtrate comes through colorless. The powder is dried, returned to the flask, treated with 50 mils of 50 per cent alcohol, shaken from time to time, and allowed to stand overnight. It is filtered into a 500-mil graduated flask and filter washed with three portions of hot 50 per cent alcohol. After cooling, an excess of 10 per cent lead acetate solution is added (usually 50 mils will be sufficient), the mixture well shaken, made up to mark with -50 per cent alcohol and thoroughly mixed. As soon as the precipitate has settled, leaving a clear supernatant liquid, 10-mil portions are pipetted, concentrated over the steam-bath to drive off the alcohol, treated with 1 to 2 mils of dilute sodium hydroxide, washed into a small beaker, and submitted to the action of hydrogen sulphide. As soon as the precipitation is complete, the lead sulphide is filtered into a tared Gooch, washed with water, and dried in vacuo over sulphuric acid. At the same time, a blank is run, using the same quantity of lead acetate made up to 500 mils, the difference in the lead sulphide figures, of course, being a measure of the lead taken up by the tannin. In this compound the lead amounts to 48.3 per cent, and it is thus a simple matter to figure the percentage of tannin. Tannic acids are widely distributed in the plant world, and reactions for them will be obtained in most mixtures containing vegetable constit- uents. The study of the different tannins occurring in the medicinal ORGANIC ACIDS— AROMATIC SERIES 697 plants has hardly commenced. Their presence in mixtures is best detected in the aqueous alkaline solution after the shaking-out process. The liquid should be evaporated until the ammonia is driven off, lead acetate added in excess, the precipitate filtered, washed, and decomposed in the presence of alcohol to which a trace of ammonia has been added. On filtering and evaporating the alcohol the tannate will be left as an ammonium salt, and will give the characteristic tannic acid reactions. Tannalbin Tannate of albumin is a compound of tannic acid and albumin. It is a fight-brown, odorless, and tasteless powder, containing about 50 per cent of tannic acid. It is practically insoluble in water or alcohol but slowly soluble in alkaline fluids, which split it up into its constituents. It is employed as an astringent in diarrhea. Tannigen Diacetyl-tannin is tannyl acetate, (CHsCO^CmHsOo, the acetic acid ester of tannin. It is a light-gray, almost odorless and tasteless powder, which undergoes no change when heated alone, even to 180° C, but softens when heated in water at 50° C. It is practically insoluble in cold water, scarcely solu- ble in hot water, but soluble in alcohol, and also in solutions of borax, sodium phosphate, sodium carbonate, lime, etc., being precipitated from these solutions b} r acids. It is rapidly saponified by boiling sodium or potassium hydroxide solutions, or gradually in the cold, into acetic and gallic acids, while ammonia produces acetic and tannic acids. Its aqueous solutions produce with ferric salts a green color, instead of the blue- violet color characteristic of tannic acid. A slightly alkaline solution in sodium phospate exhibits all the characteristics of an astringent and precipitates albumin, but these properties are destroyed by borax or more alkali. Protan — Tannin Nucleo-Proteid Protan is said to be a chemical combination of casein with tannic acid containing about 50 per cent tannic acid. When shaken with water and filtered, a colorless solution should be obtained, which should give not more than a faint trace of color with ferric chloride solution, showing absence of more than traces of free (uncom- bined) tannic acids. The resistance of Protan to the action of the gastric juice may be shown by mixing 2 grams (dried at 100° C.) with 40 mils ,2 per cent hydro- 698 ORGANIC SUBSTANCES chloric acid containing ten times the theoretical amount of 1 : 3000 pepsin necessary to digest the proteid present, warming to 40° C. for six hours, filtering off the residue, drying and weighing; 60 to 70 per cent of the amount taken may thus be recovered. The tannin may best be determined by difference, the casein being determined by decomposing it by the Gunning method and estimating the nitrogen. It is employed as an intestinal astringent in all forms of diarrhea. Tannismuth Bitannate of bismuth is the bismuth salt of tannic acid in which approximately one atom of bismuth is combined with two molecules of tannic acid having approximately the formula, Bi(OH)(Ci4H 9 09)2, and containing between 17 and 21 per cent bismuth. It is a light yellow powder with slightly astringent taste, insoluble in water, soluble in cold caustic alkalies, and in diluted hydrochloric acid. Tannismuth is used in chronic intestinal catarrh. Tannoform Tanninformaldehyde or methylenditannin, CH^CuHgOg^, is a con- densation product of formaldehyde with gallotannic acid. It forms a voluminous, reddish powder, odorless and tasteless. It is insoluble in water, but soluble in alkaline liquids and in alcohol. One one-hundredth gram of tannoform dissolved in 2 mils concentrated sulphuric acid forms a brown solution which on warming becomes green and later changes to blue. The green or blue solution, on addition of alcohol, assumes a brilliant blue color, which gradually changes to wine color, while on addition of dilute sodium hydroxide the color is pale green. Tannopin Hexamethylene-Tetramine-Tannin, or Tannon, (CuHgOg^CE^eN^ is a condensation product of tannin with hexamethylenamine. It is a fine, fawn-colored, odorless and tasteless, non-hygroscopic powder, containing 87 per cent of tannin and 13 per cent of hexamethyl- enamine. It is insoluble in water, weak acids, alcohol, chloroform, or ether, but slowly soluble in dilute alkalies. On heating dry tannopin, it swells and gives off the odor of formaldehyde. The odor of formal- dehyde is also developed on heating tannopin with dilute sulphuric or hydrochloric acid, while on boiling with sodium hydroxide solution it splits off ammonia. The clear aqueous filtrate from tannopin does not give a reaction with ferric chloride. It is used in intestinal catarrh. ORGANIC ACIDS— AROMATIC SERIES 699 Tanosal Tanosal, creosal, or creosote tannate, is obtained when birchwood creosote and tannic acid are heated with phosphorus oxy chloride. It is a dark-brown powder with a creosote odor, soluble in water, alcohol, and glycerin, but insoluble in ether, and used as an astringent and antiseptic. Bismuth oxyiodotannate or ibit is a product of uncertain composition, used as a substitute for iodoform. Pankreon is obtained by the action of tannin on pancreatic substances. It is soluble in alkaline li quids but not in water or acids, and is used in some forms of intestinal dyspepsia, gastritis, and carcinoma. Gorter found that the tannic acids ascribed to many plants are in reality chlorogenic acid, C32H 38 0ig. This body is a dibasic acid, crystal- lizing in white anhydrous needles, melting 206-207°, having an astringent and slightly acid taste. It is soluble in water, ethyl and isobutyl alcohol, and acetone, slightly soluble in ether and acetic ether, insoluble in chloro- form and carbon tetrachloride. Laevograte (a) D = -33°1. Alkalies in excess color it yellow. It can be determined by titration with alkali, the end-point being marked by a yellow color. With ferric chloride it gives a green color changing to blue and to violet, red on addition of sodium hydroxide. Warmed with sulphuric acid and manganese dioxide the odor of quinone is given off. It reduces silver nitrate on warm- ing, but Fehling's solution only slightly. Exposed to the fumes of ammonia in the air its solutions are first yellow gradually become green. In alcoholic solution it is precipitated yellow by alcoholic potash and by lead acetate. It gives well-defined crystalline salts with calcium, mag- nesium, zinc, lead, benzidine, and strychnin. It exists in coffee as the double salt of caffein and potassium, colorless, crystalline prisms, becoming yellow at 150° and charring without melting at 225°. The caffein is not removed by chloroform in the dry state, but when water is present it is separated. On boiling with potash it is hydrolyzed to caffeic and quinic acids, C32H38O19H2O = 2C9H8O4+2C7H12O6. On acetylization a crystalline body is formed having 5 acetyl groups: Ci6Hi 8 09(C9H 3 0)5. The group CieNisOg is called by Gorter hemichloro- genic acid, and is considered as proceeding from the decomposition of chlorogenic acid with the loss of one molecule of water. C32H38O19 = H20-r2Ci6Hi809. In its turn hemichlorogenic acid is decomposed by alkalies or acids into one molecule of quinic and one molecule of caffeic acids. 700 ORGANIC SUBSTANCES Chlorogenic acid would then be formed from two molecules of quinic and two of caffeic acids without the least trace of carbohydrate. Caffeic acid is 3-4 dioxycinnamic acid OH x >C 6 H3-CH = CHCOOH OBK It melts at 194-195°, gives a yellow color with ferric chloride, becoming reddish violet on adding sodium hydroxide. It is colored yellow by ammonia, reduces silver nitrate and gives a yellow precipitate with lead acetate. Quinic acid is tetraoxyhexahydrobenzoic acid. C 6 H 7 (OH) 4 COOH It melts at 161°, is lsevogyrate, soluble in water, and gives a white precipitate with neutral lead acetate but none with basic. Quinic acid has medicinal uses, being employed in uric acid diathesis in the form of salts, the most important being Uthium qumate or urosin, piperazin quinate or sidonal, hexamethylenetetramine quinate or chino- tropin, and urea quinate or urol. For the detection of the acid in plants, the following color reaction is used: Ten grams of leaves are boiled with 50 mils of dilute hydrochloric acid during one hour in a reflux apparatus. The filtrate from this is shaken with 15 mils of ether. The latter is washed with a dilute solution of sodium hydrogen carbonate and then twice with water, and to it is added a small quantity of a very dilute solution of ferric chloride, when, if chlorogenic acid is present in the leaves, a violet coloration is produced in the aqueous layer on shaking, while the ethereal layer develops a yellow tint. Out of 230 species of plants examined by Gorter in this way, 98 gave a positive result. The acid appears to occur in many plants of the orders Acanthacece Araliaceoe, Convolvulacece, Boraginacece, Gesneraceoe, and Composite. Gorter's experiments also proved that the acid of Nux Vomica, formerly known as igasuric acid, was identical with chlorogenic acid. VEGETABLE ACIDS USED MEDICINALLY There are a few other acids occurring in drugs which are extracted in a more or less pure state and used for their medicinal properties. They are more conveniently considered under the discussion of the individual drugs, but attention will be called to them at this point. Anacardic acid, from Anacardium occidentale (cashew nut), used as a vermifuge in the form of its ammonium salt. ORGANIC ACIDS— AROMATIC SERIES 701 Embelic acid, from the fruit of Embelia ribes, soluble in alcohol, ether, and cholorofonn, and used as a tape-worm expellant. Filicic acid, from Malefern, used for the same purpose. Caincic acid, from the root of Chiococca anguifuga or C. racemosa (Cainca root), soluble in alcohol and ether, and used in dropsy as a diuretic cathartic. Quillaic acid, from the inner bark of Quillaja saponaria (soap bark), soluble in alcohol and water and used as an expectorant. ARABIC ACID, C 6 H 10 O 5 +H 2 O Arabic acid'br arabin occurs in gum acacia, and may be obtained by dissolving the gum in water, adding hydrochloric acid and precipitating with alcohol. Its aqueous solution is acid in reaction and on evaporation leaves a vitreous mass which loses water above 120°, yielding metarbin. The latter does not dissolve but swells in water. THE AROMATIC GUM-RESINS AND BALSAMS The chemistry of the aromatic gum-resins and balsams is intimately connected with the chemistry of benzoic and cinnamic acids. The drugs themselves are complex mixtures, and no definite standards have been ascribed to them, in fact with the possible exception of gum benzoin it is doubtful if many of the analytical figures obtained and reported were obtained with pure products, collected under personal observation, and any data quoted must be taken with reservation. The quantitative estimation of these drugs as a whole is really of little moment in comparison with the importance of estimating the amount of the potent ingredients in such products as Xux Vomica, aconite, etc. If a quantitative value is important, it may be confined to the determi- nation of the aromatic acids in the free and combined condition, and as a matter of fact this is about all that can be accomplished with the pure drugs themselves, except where they are grossly adulterated and an approx- imate determination of the adulterant is desired. The drug chemist often finds it necessary to pass upon the quality of a specimen of gum or resin, hence we will first discuss the properties and the composition of the individual drugs in the light of our present knowledge concerning them, and before proceeding with a detailed study of the com- position, the worker should familiarize himself with the names and signifi- cance of the esters of benzoic and cinnamic acids which will figure largely in any work he will take up. These include: Benzyl benzoate. Benzyl cinnamate. Cinnamein. Cinnamyl benzoate. Cinnamyl cinnamate. Styracin. 702 ORGANIC SUBSTANCES The term " cinnamein " is applied not only to the ester benzyl cinna- mate, but to the mixtures of esters, alcohols and other substances existing in the balsams of Peru and Tolu which are not extracted from an ethereal solution by alkalies. This point must be borne in mind constantly by the analyst, because its application may become a matter of importance in legal work. Gum Benzoin Gum benzoin, according to the Pharmacopceia, comes from the Styrax benzoin (Styracese) and probably other species of Styrax, but the researches of Holmes and those of Rordoff indicate that Siam benzoin comes from S. tonkinense. The trees producing it grow in the East Indies and Southern Asia and as far as can be determined different commercial grades of gum, Penang, Sumatra and Siam all come from the same plant. Gum benzoin is the source of natural benzoic acid. Medicinally it is employed as a stimulant and expectorant in pectoral troubles and as a soothing lotion for wounds, fissures, bed sores, etc. Traumatic balsam, Turlington's balsam or Friar's balsam consists of an alcoholic solution of benzoin, storax, Peru and Tolu balsams, alces, myrrh, and angelica root, sometimes with licorice. Compound tincture of benzoin contains benzoin, aloes, storax, and Tolu. Mixtures similar in composition to Friar's balsam have been known at different times as Jesuit's drops, Wade's balsam, baume de commandeur, etc. These " baumes " will often be encountered by those who work with imported preparations. Benzoinated lard is prepared by incorporating fluid benzoin with pure lard or by digesting hot lard with powdered gum and then straining. This substance will often be found in salves and ointments mixed with various ingredients such as menthol, oil of mustard, Capsicum, etc. Sumatra Benzoin The drug occurs in irregular masses composed of yellowish or reddish- brown tears of Variable size, and a reddish-brown and translucent or grayish-brown and opaque matrix; it is brittle and the tears are milky white internally. The drug becomes soft on warming and benzoic acid is yielded on sublimation; the odor is agreeable and balsamic, resembling that of storax, and the taste is aromatic. The mass often contains con- siderable quantities of imbedded bark. Pelembang benzoin resembles the Sumatra, but is somewhat more transparent. Penang benzoin resembles the Sumatra in appearance, but resembles the Siam more in composition. ORGANIC ACIDS— AROMATIC SERIES 703 Siam Benzoin This drug occurs in concavo-convex white tears, often imbedded in a rich amber-colored translucent resin, with more or less admixed bark. The finer varieties are composed almost entirely of these tears loosely agglutinated together. It has a vanilla-like odor and a bitter taste. Constituents of Sumatra Benzoin. — It is made up of about 75 per cent of a resinous substance, benzoresin, which consists of two esters, one an ester of cinnamic acid and resinotannol amounting to 90 per cent or more of the benzoresin, and the other an ester of cinnamic acid and benzoresinol. Benzoresin on saponification yields 30 per cent cinnamic acid, 65 per cent of resinotannol, and 5 per cent benzoresinol. Sumatra benzoin also contains traces of benzaldehyde and benzol, .1 to 1 per cent of vanillin, 1 per cent phenypropyl cinnamate, 2 to 3 per cent of styracin (cinnamyl cinnamate) and 14 to 17 per cent of insoluble matter, mostly woody tissue. Constituents of Siam Benzoin. — It is composed largely of a resinous substance, siabenzoresin, consisting of 90 per cent of an ester of benzoic acid and siaresinotannol, and about 10 per cent of an ester of benzoic acid and benzoresinol. Siabenzoresin on saponification yields 38 per cent benzoic acid, 57 per cent siaresinotannol, and 5 per cent of benzoresinol. Siam benzoin also contains .3 per cent of a benzoic ester, .15 to 1.5 per cent vanillin, a small quantity of free benzoic acid and 1 to 4 per cent of woody impurities. Dieterich states that cinnamic acid takes part in the composition of Siam as well as of Sumatra benzoin. This gum usually commands from four to five times the price of the Sumatra gum. Gum benzoin is produced under the stimulus of a wound in the tree, and cannot be a product of the bark. It is probably a pathological prod- uct of the injured protoplasm. The common adulterants of benzoin are, besides excessive amounts of wood and bark, colophony, turpentine, storax, dammar, and other resins. Reinitzer 1 states that Siamese benzoin first exudes as a milky wiiite body and does not contain the brown siaresinotannol described by Ludy as its principal constituent. The benzoin in loose tears is crystalline, melting 59°, and on heating to 40 to 50° in the dark it becomes darker and amorphous, probably owing to an oxidation process. The purified crys- tals melt 72.8°, and consist of the benzoate of an alcohol which Reinitzer terms lubanol. They give a green color with ferric chloride, and are cap- able of combining with a further quantity of benzoic acid. They give the Liebermann-Salkowski reaction and a fine blue color on warming with chloral hydrate. Siamese benzoin also contains the benzoate of a body resembling Ludy's benzoresitannol, but containing more oxygen. It melts at 279° C, crys- 1 Ges. dent. Naturforacher und Aerzto, Sept., 1909; J. S. C. I., 1909, 1148. 704 ORGANIC SUBSTANCES tallizes in large prismatic needles, and is dextrorotatory in alcoholic solu- tion. Remit zer calls it siaresinol. It gives a sodium salt sparingly soluble in alcohol. It is nob oxidized on heating to 50°, does not give a color with ferric chloride, but responds to the L-S reaction. Siamese benzoin also contains an amorphous benzoate which turns reddish brown at ordinary temperatures and yields two bodies to carbon bisulphide. When heated at 100° in alkaline solution it is converted to Ludy's siaresinotannol. Sumatra benzoin likewise exudes originally with a white color and the sumaresinotannol is a secondary oxidation product. K. Dieterich has devised an examination applicable to benzoins in the commercial condition. This includes the estimation of ash and of data termed, respectively, " indirect acid number," " cold-saponification num- ber/' and " ester number." The last value is derived from the first two. The procedures are as follows: The weighed portions should be taken from a comparatively large amount of the material that has been finely powdered and well mixed. Indirect Acid Number. — One gram is mixed in a flask with 10 mils of half -normal alcoholic alkali and 50 mils of 96 per cent alcohol. The mixture is allowed to stand exactly five minutes, and then titrated with half -normal sulphuric acid and phenolphthalein until the solution is yellow, and a fresh portion of the indicator does not turn red on being dropped into the liquid, and the sodium sulphate separates readily. The super- natant liquid must be yellow. The mils of alkali neutralized by the sample, multiplied by 28.08, gives the acid number. Cold-saponification Number. — One gram of the sample is placed in a glass-stoppered flask with 20 mils of half-normal alcoholic alkali and 50 mils of light petroleum (sp. gr. .700). The flask, tightly closed, is allowed to stand for twenty-four hours at room temperature; after dilu- tion with alcohol, the liquid is titrated with half-normal sulphuric acid and phenolphthalein. The mils of alkali neutralized, multiplied by 28.08, gives the cold-saponification number. The ester number is the difference between the above data. Dieterich gives the following as the limits of values with pure samples of the different benzoins: Siam Sumatra Palambang Padang Penang Ash Per cent 0.03-1.5 140-170 220-240 50-75 95 Per cent 0.0-1.5 100-130 180-230 65-125 70-80 Per cent 1.1-4.02 113.4-130.9 198-219.8 84-91 91 Per cent 1.07 121.8-124.6 201.6-205.8 79.8-81.2 Per cent 0.38-0.77 Ind. A-N 121.8-137.2 Cold S-N 210-296.8 E-N Sol. in 96 per cent alcohol.. 87.5-91.7 94 ORGANIC ACIDS— AROMATIC SERIES 705 Balsams of Peru and Tolu These drugs are so closely related chemically that both can be considered simultaneously. The botanical source of Peru balsam has been the subject of some misunderstanding, and whether the species assigned to it has been confused with that of Tolu is a question for further study. Peru is, according to the Pharmacopoeia, a product of the Toluifera or Myroxilon periera (Leguminosae) . Kraemer describes the tree as grow- ing to the height of 50 feet and having a short trunk with branches appear- ing about 6 to 10 feet from the base. The leaves are compound and with seven to eleven alternate oblong, acuminate, glandular, punctate leaf- lets; the flowers are white and in simple axillary racemes; the fruit is a winged indehiscent one-seeded legume. The balsam is collected by mak- ing incisions in the bark and collecting it in gourds. The plant is found over the whole of Northern South America, extending through Central America into Mexico, and is cultivated in Singapore. A very fragrant vanilla-like balsam is obtained from the fruit of the same plant, and in San Salvador it is known as white Peru balsam to dis- tinguish it from the dark product obtained from the trunk. Dr. Albert Hale, 1 formerly of the Pan-American Union, has made a study of the interesting drug in its native heath, which he says is confined to a small area in the Republic of Salvador. This Balsam coast extends along the western Pacific slope of Salvador, between the ports of Acajutla and La Libert ad, a distance of only scant 40 miles, or allowing a short distance on either side the extreme limits of the recognized growth of the tree in all this region is only 50 miles. Assuming that this strip has a depth from the coast of 15 miles, which is very liberal indeed, there is an area of only 750 square miles at the most over which the tree is exploited. Why nature restricts her activities so curiously as in this instance is an interesting problem for the botanist. The balsam tree is one of the most beautiful of a tropical forest. It may be found, in its natural state, in groups so evenly distributed as to suggest a plantation, but usually it grows rather isolated from its kind and even separated from its neighbors a respectful distance. In appear- ance it is a stout tree, measuring at full development about 1 meter (about 40 inches) in diameter and reaching upward as tall as 25 to 35 meters (80 to 115 feet). The trunk is cylindrical, the bark somewhat cracked, of a grayish or ashen color, with whitish blotches due to the parasitic lichen that cling to it. Few branches spring from it until the spread is reached, but the robust roots, especially in mature trees, extend along the surface 1 Bull. Pan-Amer. Union, Vol. 22, 1911, 880. 706 ORGANIC SUBSTANCES of the ground before sinking finally beneath the soil. The bark of the branches and twigs is also gray or reddish and covered with numerous little white and hard excrescent-like spots. The outer wood is white, the inner is red or almost black, and extraordinarily hard ; as it is also very durable it offers splendid material for construction work and furniture. Flowering takes place through a stem of about 10 centimeters (4 inches) long, with numerous white blossoms. The fruit is a pale yellow, mem- branous, feathery pod, with only one seed, as a rule. The life of the balsam tree is about one hundred years. The gathering of the sap is begun at the age of twenty-five years and may be continued indefinitely unless some accident to the tree occurs meanwhile. A well-nourished balsam tree will yield on the average from 3 to 4 pounds of sap a year; the best of them, if cared for in anything like a modern agricultural system, can part with 8 pounds a year and still remain uninjured for the next seasom. Only the inner bark yields pure balsam, and then only from the mature tree; although the immature tree does give juice, it is nevertheless thin, light, poor in quality, and of small commercial value. This report from a man who has been on the ground certainly must be regarded in the light of authority. Tolu comes from Toluifera or Myroxilon balsamum, a tree which, according to Kraemer, reaches the height of 75 to 80 feet and whose branches appear at a height of 50 to 60 feet. Otherwise its description is the same as T. pereira. It grows in Northern South America. T. pernifera growing in Northeastern South America yields a balsam rimilar to Tolu. It would seem as if Kraemer's description of the Tolu balsam tree more nearly corresponded with the tree which Hale found yielding Peru balsam. Adulterants. — Peru balsam may contain Tolu balsam and storax, copaiba and gurjun balsams, turpentine, colophony, benzoin, castor oil. Owing to the rigid inspection during the last few years the grosser adulter- ation has ceased, but there exist in the market certain so-called " artificial " or " synthetic " Peru balsams, made from storax, Tolu and other sub- stances with probably a little Peru. Tolu balsam is relatively cheap and is not as liable to adulteration as is Peru. Colophony is the principal adulterant. Peru is a warm stimulating stomachic and expectorant and emollient. It is used in chronic catarrh, asthma, phthisis, and pectoral complaints generally, and also in gonorrhea, leucorrhea, amenorrhea, chronic rheuma- tism, and palsy. Locally it is employed for ulcers, running sores, skin affections, and blood poisoning. Combined with benzoin, tolu, etc., it is one of the constituents of Friar's balsam and other balsams and " baumes." It is dispensed in ORGANIC ACIDS— AROMATIC SERIES 707 syrups and with mucilage of acacia and mixed with lead plaster it is used as a remedy for blood poisoning, wounds, and other skin affections. Tolu balsam has the same medicinal properties as Peru and will be found in the same class of compounds. Its greatest fame, however, is as a stimulant to the bronchial mucous membrane, and it occurs in the formulas of many mixtures recommended for coughs and colds. Syrup of Tolu is official in the Pharmacopoeia; liquid mixtures contain Tolu together with opium, ammonium chloride, licorice, wild cherry, and aromatics in syrupy form. Inhalants contain Tolu, iodin, phenol, gly- cerin, camphor, and cubebs. Bronchial tablets are composed of Tolu with ammonium chloride, licorice, cubeb, Hyoscyamus, senega, and ipecac, sometimes with opium; and other formulas include Tolu with licorice, cubeb, and sassafras; with coltsfoot, licorice, peppermint, Capsicum, and anise. Throat pastiles are composed of mixtures of some or all of the following: Tolu, coltsfoot, licorice, sugar, acacia, horehound, wild cherry, anise, cubeb, and Capsicum. Peru is a viscid balsam like syrup, honey, or molasses, of a dark red- dish-brown color, a fragrant vanilla-like odor, and a warm bitterish taste, leaving when swallowed a burning or prickling sensation in the throat. It does not harden on exposure. Tolu has at first a soft tenaceous consistency which varies considerably with the temperature. By age it becomes brittle and hard like rosin. It is shining, translucent, of a reddish or yellowish-brown color, a highly fragrant odor and a warm, somewhat sweetish and pungent, but not dis- agreeable taste. Allen tersely summarizes these drugs as follows : The cinnamic balsams are closely allied, consisting essentially of the benzyl and cinnamyl esters of benzoic and cinnamic acids, mixed with resinous oxidation products of these esters, free benzoic and cinnamic acids, and the Irydrocarbon cinnamene. The leading or characteristic constituents of Peru balsam may be said to be the cinnamein or benzyl cinnamate and styracin or cinnamyl cinnamate. Free benzyl alcohol is also present. In Tolu balsam, on the other hand, the proportion of resin is large; but of the esters benzyl benzoate predominates, and cinnamyl benzoate and cinnamate exist in but small proportions. In liquid storax of Mexican origin, phenylpropyl cinnamate exists in considerable quantity together with two isomeric alcohol-like substances called a and storesinol, to which the formula C3 6 H 5 5(OH)3 is attributed, and the cinnamic esters of these substances. In some cases the substances obtained from the cinnamic balsams have been decomposition products of the methods of analysis. The following method may be adopted for the recognition of the principal constituents of aromatic balsams: The substance is dissolved in 2 or 3 708 ORGANIC SUBSTANCES parts of ether, and filtered from any insoluble matter. The solution is agitated with an equal volume of normal sodium hydroxide, the alkaline liquid withdrawn, and the agitation repeated with a fresh quantity of solution. If desired, the total acidity of the balsam can be deduced from the titration of an aliquot part of the alkaline liquid. The ethereal layer is then washed with water, and distilled at a gentle heat, the residue of neutral ester, etc., being weighed. The residue is then fractionally dis- tilled. The first fraction will contain any cinnamene which may be present, the next being rich in benzyl alcohol, which may be extracted by agitation with water and will yield benzaldehyde and benzoic acid by oxidation. Cinnamyl alcohol and benzyl benzoate pass over next, and at the higher temperature benzyl cinnamate and cinnamyl benzoate and cinnamate may be obtained. These esters suffer more or less decomposition unless the distillation is conducted in vacuo, and hence the last fraction consists largely of cinnamic acid, which can be removed by agitating the distillate with sodium carbonate solution. The alkaline liquid separated from the ethereal solution should be saturated with carbon dioxide, which precipi- tates much resin. The liquid is filtered, concentrated, and treated with hydrochloric acid, when a bulky precipitate is obtained representing the free benzoic and cinnamic acids of the balsam. These substances may be identified by their ordinary reactions. For their approximate separa- tion, one-half of the precipitate may be boiled with milk of lime and the liquid filtered and allowed to become cold, when the sparingly soluble calcium cinnamate is deposited in shining needles, the more soluble ben- zoate remaining in solution. When an exact estimation of the free acids of a balsam is desired, it is better to agitate the ethereal solution with sodium carbonate instead of sodium hydroxide, as the latter reagent is liable to cause some decomposition of the esters. Methods for the Examination of the Peru and Tolu. — Direct Acid Number. — One gram of the sample is dissolved in 200 mils of alcohol (96 per cent) and titrated with decmormal alcoholic alkali, using phenol- phthalein. The mils of alkali required multiplied by 5.616 gives the direct acid number. Cold Saponification Number. — The procedure is mainly as given under " Benzoin," using 1 gram of the sample in a 500-mil glass-stoppered flask with 50 mils of light petroleum (sp. gr. .700) and 50 mils N/2 alcoholic alkali. After standing twenty-four hours at room temperature, 300 mils of water is added, well shaken, until the separated dark alkali salt has been dissolved, and the solution titrated, with continuous agitation, with N/2 sulphuric acid in the presence of phenolphthalein. The mils of alkali neutralized by the sample, multiplied by 28.08, gives the cold saponifica- tion number. ORGANIC ACIDS— AROMATIC SERIES 709 The ester number is obtained by subtracting the direct acid number from the cold saponification number. Ether Insoluble Matter. — This is obtained by Dieterich by adding warm ether in small portions to a weighed portion of the sample until a portion of the solvent no longer leaves any residue on evaporation. The undissolved portion is then weighed. It will probably be better to extract in a Soxhlet tube. Aromatic and Volatile Ingredients. — The ethereal extract is shaken with 20 mils of a 2 per cent sodium hydroxide solution, separated and evaporated at room temperature until no odor of ether is perceptible. The residue is placed for twelve hours in the desiccator, weighed, placed for a second twelve hours in the same and weighed again. The mean between these two weights is taken as the datum for fixed matter from which the volatile matter can be calculated. Esters of Resin-acids. — The alkaline solution separated from ether by the action of the alkali, as noted in the last paragraph, is rendered acid by dilute hydrochloric acid, filtered through a tared filter and washed by the aid of a filter pump with as little water as possible until the wash- ings are free from chlorides. The residue dried at 80° to constant weight is taken. With these processes, Dieterich obtained from commercial samples of Peru Balsam the following range of data: Sp.gr : 1.135 1.145 Direct acid number 60.0 80.0 Cold saponification number 240 . 270 . Ester number 180.0 200.0 Resin esters 20.0% 28.0% Aromatic and volatile ingredients 60.0% 77.0% Ether insoluble 1.5% 4.5% From authentic pure specimens from Honduras the following figures were obtained. / II III Direct acid number 77.4 76.9 77.3 Cold saponification number 241.0 214.3 215.0 Ester number 165.6 137.4 137.6 Resin esters 15.7% 13.2% 17.3% Aromatic and volatile ingredients . . 71.4% 77.5% 73.6% Ether insoluble 4.4% 4.3% 3.5% The United States Pharmacopoeia requires that Peru balsam shall have a sp. gr. between 1.130 and 1.160 at 25°, that when mixed with sodium hydroxide solution, one extraction with ether shall remove 50 to 56 per cent of cinnamein, and that the latter shall have a saponification value of from 235 to 238. According to the same authority, Peru balsam must 710 ORGANIC SUBSTANCES have an acid value not less than 50 nor more than 84. The German Pharmacopoeia regulation is satisfied if the 56 per cent of cinnamein is obtained by three successive extractions with ether, but it must require at least 23.66 per cent of potassium hydroxide for hydrolysis, and the balsam must have a cold saponification value not less than 224.6. The acid number of Tolu balsam according to the U. S. P. should be not less than 112 nor more than 168, and the saponification value not less than 154 nor more than 220. The U. S. P. method for determining these figures is as follows: Dissolve about 1 gram of the Balsam, accurately weighed, in 50 mils of alcohol, add 1 mil of phenolphthalein T. S. and titrate the solution with half -normal alcoholic potassium hydroxide V. S. The acid number thus obtained is not less than 112 nor more than 168. Now add sufficient half- normal alcoholic potassium hydroxide V. S. to the neutralized liquid to make the total amount of the volumetric alkali solution exactly 20 mils; heat the liquid on a water-bath for half an hour, under a reflux condenser, and allow it to cool. Mix this liquid with 200 mils of distilled water, or more if necessary, and titrate the excess of potassium hydroxide with N/.5 sulphuric acid V. S.; the total amount of N/.5 potassium hydroxide V. S. consumed corresponds to a saponification value of not less than 154 nor more than 220. The detection of rosin in Peru balsam may be effected by dissolving the balsam in ether and shaking the solution with sodium hydroxide which will dissolve out the acid constituents of the resin including any abietic acid. The alkaline liquid is then drawn off into another separator, acidi- fied, and shaken with ether, the ether evaporated and the residue of mixed acids washed several times with boiling water to remove the cinnamic and benzoic acids, and then subjected to the test for abietic acid. This acid dissolves in chloroform and on adding a drop or two of acetic anhy- dride followed by a drop of concentrated sulphuric acid a purple color changing to blue is obtained. Perrot and Goris detect rosin in Tolu by shaking 5 grams with 30 mils of carbon bisulphide in the cold or with gentle warming. The solvent is decanted and evaporated, the residue treated with 10 mils of light petro- leum ether, filtered and shaken with a 1-1000 solution of copper acetate. The presence of rosin is indicated by the appearance of a green color. The authors state the reaction is not applicable to Peru balsam as the pure drug gives a green color. This assertion may be correct, but it is also possible that at the time the researches were in progress the Peru balsams all contained rosin. Hartwich and Jama 1 from a study of the situation conclude that the balsams all come from the same tree, but of distant botanical varieties: 1 Schweiz. woch. Chem., Pharm. 1909, 47, 625 and 841; J. S. C. 1 , 1901,1271. ORGANIC ACIDS— AROMATIC SERIES 711 Tolu from Myroxylon balsamum (L) var a-genuinum (Baill) . Peru from Myroxylon balsamum var perier3e (Baill) . Quino-quino Myroxylon balsamum var J. punctatum (Baill). They tabulate the analysis of these bodies as follows : Saponification No. Cinnamein Saponification No. of Cinnamein 257.4 65 236 255.5 65.5 243.5 261.3 65.9 243.6 263.7 62.4 262 265 61 264 255.3 60.8 265 272.1 57 271 269.3 60 265 A sample labeled " synthetic " gave: Saponification No. 263.7, cinnamein 62.5 per cent, saponification No. of cinnamein 244. Heiduschka and Rheinberger r record the results of some observations made with a bromination test upon Peru balsam containing various admix- tures. A flask is fitted with a two-hole cork containing a pipette graduated to hold 1 mil of bromin and a thermometer; 20 mils of the solution of 10 grams balsam in 100 mils chloroform are introduced into a flask and when the thermometer has attained the temperature of the mixture the bromin is added and the temperature noted after lj minutes. The pure balsam showed a value of 17°. Drug Tolu Castor Oil Storax Copaiba Turpentine Venice Turpentine Resin Santal OH Gurjun Balsam . . . Benzoin Bromin value with o per cent admixture. Degrees Bromin value with 10 per cent admixture. Degrees 17 17 17.75 18.25 17.85 19 18.00 18.75 18.75 21.50 18.75 20.50 19.00 20.00 19.50 21.75 19.75 22.75 r- 18.25 Jensen 2 records that cinnamein from reliable Peru showed iodin numbers of 23.8 and 25.5 against 1.5 from synthetic esters. Upon frac- 1 Pharm. Centrh., 50, 220. 2 Pharm. J., 90, 210. 712 ORGANIC SUBSTANCES tional distillation of cinnamein the first 30 per cent was optically active when derived from the true balsam, but inactive when derived from the synthetic. Benzylbenzoate boils approximately 320° (ordinary pressure), 173° at 9 mm., sp. gr. 1.121, saponification number 264.1. Benzyl cinna- mate boils 360° approx. (ordinary pressure), 213-214° at 9 mm., sp. gr. 1.098, saponification No. 235.3. Merck's Method of Determination of Acid and Saponification Value. — One gram balsam is dissolved in 50 mils alcohol, 6 mils N/2 potassium hydroxide added, a few drops of phenolphthalein and after shaking, 200- 300 mils water; the excess of alkali is titrated with N/2 hydrochloric acid and the volume of alkali used up by the balsam X 28 gives the acid value. The saponification value is determined by dissolving 1 gram balsam in 50 mils alcohol, adding 20 mils N/2 alcoholic potash, heating one-half hour over the steam-bath, adding 200 to 300 mils water and titrating with N/2 hydrochloric acid. The volume of alkali consumed by the saponi- fication X28 gives the saponification value. A method for determining " cinnamein " in aromatic balsams has been described by Lehmann and Muller. 1 A mixture of 2.5 grams of the balsam and 5 mils water is shaken for one minute with 30 mils ether in a 75-mil separator, 5 mils sodium hydroxide solution are added, shaken one minute and allowed to stand ten minutes ; the aqueous solution run off until about 3 mils are left. After the addition of .5 gram tragacanth, the separator is shaken for three to five minutes and the ether poured off or filtered into a tared flask, evaporated and weighed. Delpin's 2 method of testing balsams in order to differentiate between the acid and resin esters is as follows: Balsam is dissolved in ether and shaken with N/1 sodium hydroxide, followed by 10 mils water. The ether is then evaporated and residue weighed as cinnamein. The alkaline solution is treated with 2 grams sodium bicarbonate and a stream of carbon dioxide slowly driven through the mixture for an hour, the solution filtered through a tared Gooch and the precipitate washed with warm water until the washings are no longer alkaline, the filtrate and washings being reserved. The precipitate on the Gooch is dried and weighed as resin ester. The alkaline solution is then treated with excess of hydrochloric acid, and the precipitated acids collected on a tared Gooch, washed with boiling water, dried and weighed as resin acids. The acid filtrate and washings are then shaken out with ether, and the cinnamic acid determined gravimetrically by drying in vacuo or by titrating in alcoholic solution. i Arch. Pharm., 1912, 250, 1. 2 Svensk. Farm. Tidshr., 1907, 3, 415. ORGANIC ACIDS— AROMATIC SERIES 713 Honduras Balsam Tschirch and Werdmuiler, 1 from an examination of three samples of light balsam, report specific gravity 1.0886, 1.0905, 1.0884, average acid value 32.67, average saponification value 173.2, corresponding to a total amount of 45.66 per cent cinnamic acid and 8.6 per cent free acid. Its odor resembles storax. When shaken with sodium carbonate it yielded cinnamic acid and a resin ester which yielded cinnamic acid and hondu- roresinol, melting 166-167°. On boiling with strong potassium hy droxide a phytosterol-like substance separated on cooling. The alkaline solu- tion also yielded an amorphous substance called /3-honduroresin, melting 300°, insoluble in hot alcoholic potash, alcohol, ether, acetone, or petroleum ether with no phytosterol reactions. The " cinnamein " remaining after extracting the ether solution with alkali is a mixture of a hydrocarbon, CgHio, hondurane, boiling 154-155°, distyrene; another hydrocarbon, C9H12, boiling 140-155°; cinnamyl and phenyl-propyl cinnamates, and hondurol, C17H16O2, a dihydric unsaturated alcohol, melting 42.5°. Two dark samples gave an average acid value 29.9 and saponification value 153.9. They yielded products similar to the above. Tschirch and Werdmuller 2 have investigated Cabureiba balsam from Myrocarpus fastigiatus and M. frondosus from Peru, an aromatic balsam. It contains benzoic acid, vanillin, and a new resinotannol, but no cinnamic acid nor cinnamein. Patents have been obtained for soluble preparations of Peru balsam obtained by mixing the ingredients in the following proportions : 100 grams balsam with 50 grams glycerin, 50 grams 90 per cent alcohol and 50 mils potassium hydroxide solution 43° B., heating for several hours at 60° C. and running in gaseous formaldehyde, the process being continued until the product forms a clear solution with water. Storax Storax, styrax, or Oriental sweet gum, is obtained from the plant Liquid- ambar orientalis (Hamamelidaceae) . The tree grows profusely in the forests of Asia Minor, it is from 20 to 40 feet high. The leaves are palmate, the divisions obscurely three-lobed, serrate, smooth, bright green on upper and pale on under sufrace. Other species of Liquidambar yield a similar, if not an identical gum; L. styraciflua, the sweet-gum tree of this country exudes a storax used to some extent commercially and the resins from L. formosana and L. altingiana are of commercial importance. Storax is also obtained from the trees of the closely related genus Altingia. 1 Arch. Pharm., 248, 420. 2 Aj C h. Pharm. 248, 431. 714 ORGANIC SUBSTANCES At the present time our Pharmacopoeia recognizes only the resin of L. orient alis. It may be found adulterated with turpentine, colophony, castor or olive oils, labdanum, and cheap resins. It is used for the same purposes as Peru and Tolu balsams and may be found in the same class of formulas. Storax furnishes the aromatic component of some of the imitation Peru balsams. An extract of the bark of L. styraciflua furnishes a mucilaginous astringent which has been used in diarrhea and dysentery. Storax is a viscid, grayish, more or less opaque semiliquid mass, deposit- ing on standing a heavier dark brown, oleoresinous stratum; translucent in thin layers; odor agreeable, taste balsamic. It consists of about 50 per cent of two resin alcohols, a-storesin, and /3-storesin, which are partly free, partly in combination with cinnamic acid and partly with sodium, a-storesin (a-storesinol) is an amorphous substance that is very sparingly soluble in water and forms a crystalline compound with potassium. /3-storesin (/3-storesinol) occurs in white flakes somewhat soluble in water, and not forming a crystalline compound with potassium. Storax also contains from 10 to 20 per cent of an ester consisting of cinnamic acid and storesin; from 5 to 10 per cent of cinnamyl cinnamate; 10 per cent of phenylpropyl cinnamate, odorless and viscid; 2 to 3 per cent of phenylethylene (styrene) which occurs as a colorless liquid possessing the odor and pungent taste of the drug; from .5 to 1 per cent of a laevorota- tory volatile oil; 2 to 5 per cent of free cinnamic acid; about .15 per cent vanillin, and small quantities of benzoic acid, ethyl vanillin, resin, caoutchouc, and undetermined substances. It sometimes yields more than 20 per cent of free cinnamic acid. Burmese storax from Altingia excelsa is a soft white crystalline balsam developing the fragrant odor of styrene, and contains about 50 per cent of cinnamic esters. A brown solid balsam is also obtained from the same tree having a cinnamein-like odor, and containing a trace of free cinnamic acid and about 10 per cent of cinnamic esters. The examination of storax should in general follow the lines indicated under the other balsams and the same directions may be followed. Tschirch and van Itallie 1 have examined storax from L. orient alis and find free cinnamic acid, vanillin, stryol, styracin, ethyl cinnamate, and storesinol partly free and partly as ester. No benzoic acid was detected. Storesinol is a white, odorless powder, melting 156-161°, C16H26O2, insoluble in light petroleum ether, but dissolves in other organic solvents and in alkalies. It is isomeric with benzoresinols but with a 1 Arch. Pharm., 239, 506. ORGANIC ACIDS— AROMATIC SERIES 715 lower melting-point. It forms crystalline compounds with potassium hydroxide, separating in acicular crystals. It yields acetic and salicylic acid on alkaline fusion. On distillation with zinc dust it yields, phenol, toluene, and benzene. It does not acetylate nor give a benzoyl compound, nor any derivative with hydroxylaixiin nor phenyl hydrazine. Oxidized with nitric acid it gave picric and oxalic acids. The same authors 1 working on American storax say that the con- stitutents are much the same, consisting of cinnamic acid, vanillin, styrol, styracin, cinnamic phenyl propyl ether, and styresinol partly free and partly in form of cinnamic ester. No ethyl cinnamate was detected. Styresinol is apparently an isomeride of storesinol having the same formula and melting-point but differing in optical activity, its specific rotation being +13° 19' as compared with +52° for storesinol. In all other respects the resins are identical. Determination of Total Cinnamic Acid. — The sample is saponified with excess of alcoholic potash, the alcohol evaporated, the residue dis- solved in water, transferred to a separator, washed with 10 mils ether and the ether rejected. An excess of dilute sulphuric acid is added and the liberated acids shaken out with 3 portions of ether. The ether is collected in a flask, evaporated, and the residue boiled with 50-100 mils of water under a reflux; the water filtered off while hot into another separator; and the extraction with boiling water repeated twice. The combined aqueous solutions when cool are then shaken out three times with ether, the solvent filtered and evaporated and the residue dried in vacuo or titrated. Umney records the analyses of samples of storax imported from 1907- 1911 in which the acid values rose from 68 to 111, the ester values fell from 112 to as low as 14 in individual cases, but averaged in the last 60- 70, and the cinnamic acid free and combined fell from 19 per cent to 2.5 per cent. He also worked on two samples which Professor Greenish had kept for eleven years, the crude resin showing acid values 50.6, ester value 100.4, total cinnamic acid 20.6 per cent. This sample yielded a purified storax with acid value 60.1, ester value 130.1 and total cinnamic acid 25.5 per cent. Purified storax is prepared by dissolving the resin in alcohol, separating from the insoluble portion and removing the solvent. It is a brownish- yellow viscous balsam, transparent in thin layers, with an agreeable odor and balsamic taste, entirely soluble in alcohol and ether. When heated on a water-bath it should lose not more than 5 per cent. The acid value should range between 60 to 90 and the ester value 110 to 140. Storax adulterated with rosin yields to petroleum ether from 55 to 65 per cent, the extract having an acid value 116 to 121, and saponifica- *Arch. Pharm., 239, 532. 716 ORGANIC SUBSTANCES tion value (cold) 171 to 177. Pure storax gives a 37 to 47 per cent extract with acid value 37 to 47 and saponification value (cold) 194 to 198. Nan-ta-yok or Burmese Storax Hooper * examined this balsam, which has long been used in Burma as incense and for medicinal purposes. It is produced by Altingia excelsa (Noronha), a large tree (150 to 180 feet high) growing in the forests of the Indian Archipelago, Burma, Assam, and Bhutoa, and especially in the Tenasserim province of Burma. It is also found in China, Java, Cochin China, New Guinea, and Sunda Archipelago. Three samples of resinous balsam from Java examined by Tschich and van Itallie were said to be the products of two species of Altingia, but in GreshofPs opinion both trees were Altingia excelsa. The two aromatic exudations from South Tenasserim examined by the author had the following properties : Soft White Crystalline Balsam. — This resembles honey when fresh, but after two years crystallized, and become white, and had a fragrant odor of styrol. It melted at 41° C, and when heated on the water-bath lost 7.65 per cent in weight, the volatile substances being chiefly essential oils. It gives the following values: Acid value, 24.96; saponification value, 199.35; and iodin value, 57.3. About hah the balsam consisted of an ester of cinnamic acid, the amount of the lattei separated being 37 per cent calculated on the original balsam. Dark-brown Solid Balsam. — This consisted of resinous masses which yielded brown powder with an aromatic odor in which that of cinnamon predominated. After clarification with alcohol two samples gave the following results: Resins, 53.72 and 54.70; organic impurities 19.09 and 28.05; inorganic impurities 22.24 and 10.67; and volatile oil and loss, 4.95 and 6.58 per cent. The purified resin (m. pt. 68° C.) was clear, gave amber color, and had the fragrant odor of the crude balsam. It was soluble in chloroform, carbon bisulphide, and benzene, partially soluble in acetic ether, and slightly soluble in petroleum spirit. Acid Value Saponification Value Iodine Value Crude Resins Pure Resins 52.48 76.80 130.10 130 . 44 41.07 51.68 The brown balsam contained a trace of free cinnamic acid, and 9.7 per cent of that acid in the form of an ester. The author's conclusion is that the white balsam is valuable as a perfume and as a source of cinnamic 1 Agri. Ledger, 1904, 115. ORGANIC ACIDS— AROMATIC SERIES 717 acid, while the brown balsam is of value a-s a perfume and as incense. Both possess a sweeter aroma than genuine storax, and when heated with sulphuric acid and potassium bichromate, both evolve an odor of benzal- dehyde. If examined by Dieterich's method the brown resinous balsam cannot be regarded as true storax, while the white balsam only agrees with that resin in the saponification value. Hence the author's results confirm the statement of Tschirch and van Itallie that Nan-ta-yok resin differs in constitution from the genuine storax of Asia Minor. SULPHONIC ACIDS AND THEIR DERIVATIVES Sulphanilic acid, CeH^NH^jSOsK This acid, which is chemically amidobenzene-p-sulphonic acid, is pre- pared by heating anilin sulphate to 200° C. It crystallizes with 2H2O, readily soluble in hot, but sparingly in cold water, and insoluble in alcohol and ether; on heating to 280-300° it is decomposed. It forms salts with bases, but does not combine with acids, the basic character of the amido group being neutralized by the acid character of the sulphonic ; when fused with alkali it yields anilin. Chromic acid oxidizes it to quinone. When dissolved in dilute sodium hydroxide and mixed with a slight excess of sodium nitrite, and poured into cold dilute sulphuric acid, diazobenzene sulphonic acid is formed. /NHa /N : NOH C 6 H< +HOXO = C 6 Hi < +H 2 0, \S0 3 H X S0 3 H which compound immediately loses water and separates as the anhydride "NT • Ttf in colorless C6H4C X S0 3 In medicine sulphanilic acid is used in Ehrlich's diazo reaction for typhoid urines, and is sometimes given for chronic catarrh. /S0 3 Xa Cosaprin, Sodium acid sulphanilate, CqEa\ is used as x XH(COCH3) an antipyretic. PHENOL SULPHONIC ACIDS Phenol-o-sulphonic acid, C6H4OHSO3H, is formed, together with a small quantity of the p-acid when a solution of phenol in concentrated sulphuric acid is kept for some time at ordinary temperatures. It has been stated that on heating to 100-120° the o-acid is gradually converted to the p-acid, but recent experiments indicate that this is erroneous. 718 ORGANIC SUBSTANCES The o-acid known as ortho-sulphocarbolic or sozolic acid, is soluble in water, glycerin, and alcohol, but not in ether. It has a phenol-like odor and gives a violet color with ferric chloride. It is used extensively as an antiseptic. Aseptol, which is sold as a 33 per cent solution of the o-acid, really consists in large parts of the p-acid. Phenol-p-sulphonic acid is a powerful antiseptic and its sodium and zinc salts are official in the Pharmacopoeia. Solutions of this acid coagu- late albumin, and give a violet color with ferric chloride, but the phenol sulphonic acids are readily distinguished from salicylic acid as they are not removed from acid solution by ether or chloroform. On boiling a solution of the acid with an equal volume of concentrated nitric acid and neutralizing with potassium hydroxide, a yellow color due to picrate is produced. On adding bromin to a solution of the acid a precipitate of tribrom phenol is thrown down, and sulphuric acid is liberated in solution, recognizable by its insoluble barium precipitate. The acid, on heating to 250° with potash, gives resorcinol. The potassium salt on fusion with potash yields catechol. When the sodium salt is ignited it leaves in part a residue of sodium sulphate. The zinc salt does not yield the sulphate unless sodium car- bonate is present. The aluminum salt is known as Sozal. It is soluble in water and used as a substitute for iodoform. Mercury phenol parasulphonate also called Hydrargyrol, is soluble in water and glycerin and insoluble in absolute alcohol. It is used as an antiseptic in place of mercuric chloride. The estimation of the acid may be accomplished by the nitric acid reaction, precipitating the sulphuric acid formed, by means of barium, and weighing the barium sulphate, or it may be done by the following bromin method: .2 to .3 gram of the acid or salt with .6 to 1 gram barium chloride are dissolved in 100 mils water containing 10 mils hydrochloric acid 1.19 sp. gr. The mixture is heated to 60 to 65° and slowly treated with a solution containing, 1 gram potassium bromate and 5 grams brom- ide in 100 mils, until a faint persistent yellow color is produced. A small quantity of an alcoholic solution of phenol is added to remove the excess of bromin and then sufficient alcohol to dissolve the tribrom phenol. The container is then boiled and the liquid decanted from the barium sulphate, which is repeatedly washed with 50 per cent alcohol, then with water and finally filtered and weighed. Ni'troparaphenol sulphonic acid in the form of a soluble salt with potassium and mercury known as Phenegol is a reddish-brown, odorless, tasteless powder, soluble in water and used as an antiseptic. Its composi- tion is given as CeHsCONC^SCfeK) : Hg : (KS0 3 N020)C 6 H5. Analogous to the phenolsulphonic acids are resorcinoldisulphonic acid, ORGANIC ACIDS— AROMATIC SERIES 719 C 6 H2(OH)2(S0 3 H)2, and thymol sulphonic acid, Ci H 12 OHSO 3 H, both soluble in water and alcohol, the former decomposing above 100° and the latter melting at 91-92°. Diiodoparaphenol sulphonic, sozioclolic acid or soziodol, C6H2i2(OH) SO3H, is a white crystalline powder, slightly soluble in cold water, readily in alcohol and glycerin, decomposed on heating to 200° with evolution of iodin. It gives a violet color with ferric chloride and a white precipitate with silver nitrate soluble in nitric acid. Its salts are used to some extent in medicine, especially those of mercury, sodium, potassium, zinc, and magnesium. They are antiseptic and antipyretic. Ichthyol Compounds On distilling certain bituminous shales an oily product known as crude ichthyol oil is obtained. This raw product on treatment with concen- trated sulphuric acid yields a sulphonated product, probably a mixture of sulphonated hydrocarbons, and other sulphonated products with a variety of undertermined substances. On neutralizing the sulphonated acids with ammonia and evaporating to a thick syrup, the product known commer- cially as ichthyol or ammonium ichthyol sulphate is obtained. There are a number of other ichthyol compounds and they are all used for anti- septic purposes, owing their efficiency probably to the sulphonic bodies contained therein. They are recommended also as antiphlogistics, anodynes, and alteratives and are dispensed for internal and external use. They are often found in ointments, suppositories, and bougies, in remedies for ivy poisoning and in mixtures for uterine ailments combined with iodin, boric acid, Hydrastis, glycerin, and phenol. There are a number of imitations of the natural product on the market, but whether they are any less effective than the genuine is still a matter for physiological research. The sulphur in the product made from the natural distillate is present in three forms, first the combined sulphur naturally occurring in the dis- tillate, second, the sulphur introduced by sulphonating and third, that in the form of sulphate. Both of the ammonium and sodium compounds are brown syrupy liquids with a bituminous odor and taste. Water or a mixture of alcohol and ether dissolves the liquid, and pure alcohol or ether takes it up in part. Hydrochloric acid precipitates a resinous mass which is soluble in ether. The ammonium compound gives off ammonia on warming with caustic alkalies. The compounds of lithium, zinc, mercury, and silver have been prepared and are used as drugs. The reactions and tests for ichthyol (the ammonium compound) may be briefly stated as follows : 720 ORGANIC SUBSTANCES The aqueous solution (1:10) has a faintly acid reaction upon blue litmus paper, and yields a greenish-black, resin-like precipitate upon the addition of hydrochloric acid. This precipitate is partially soluble in ether and alcohol; soluble in water, but if dissolved in the latter solvent it may again be precipitated from solution by the addition of hydrochloric acid. With barium chloride test solution it gives a brownish-black precipi- tate which is soluble in dilute hydrochloric acid. Ichthyol is incompatible with acid and saline solutions, fixed alkalies, their carbonates and iodides, alkaloidal salts, and mercuric chloride. If dried at 100° C. ichthyol should not lose more than 47 per cent of its weight. If from 5 to 6 grams of ichthyol are weighed into a flask, 25 mils of potassium hydroxide test solution and 100 mils of water added, the mixture distilled until no more ammonia passes over, the distillate col- lected in 15 mils of normal sulphuric acid to which 1 drop of methyl red test solution has been added, and the excess of acid then titrated with N/10 potassium hydroxide, the amount of normal sulphuric acid con- sumed should correspond to from 2.9 to 3.4 per cent of total ammonia (NH 3 ). ' If from 5 to 6 grams of ichthyol are weighed into a beaker, diluted with 50 mils of water, 10 mils of a 10 per cent solution of albumin added, followed b}' 5 portions of 5 mils each of diluted hydrochloric acid, shaking after each addition, the mixture made up to a volume of 500 mils and filtered through a diy filter, and if 200 mils of the filtrate are heated to boiling, 10 mils of barium chloride test solution added, the mixture allowed to stand for twenty-four hours, the precipitate of barium sulphate collected, heated and weighed in the usual way, the weight of barium sulphate obtained should correspond to from 5.7 to 6.2 per cent of ammonium sulphate. If from .5 to 1 gram of ichthyol is weighed into a Kjeldahl flask, diluted with 30 mils of water, 5 grams of potassium chlorate added, followed by 30 mils of nitric acid, the mixture evaporated to about 5 mils, 25 mils of hydrochloric acid again added, this solution evaporated to about 5 mils 100 mils of water added, the solution heated to boiling, 10 mils of barium chloride rest solution added, the mixture allowed to stand for twenty- four hours, the precipitate of barium sulphate collected, heated, and weighed in the usual way, the weight of barium sulphate should corre- spond to at least 10 per cent of the total sulphur. If the ammonia contained in the ammonium sulphate as previously determined in ichthyol is calculated, and the result subtracted from the " total ammonia " as previously determined, the remainder should repre- sent the ammonia combined with the organic sulphonic acids. If this ORGANIC ACIDS— AROMATIC SERIES 721 value is multiplied by 1.88 the result should represent the sulphur present in the sulphonic acids in an oxidized state, i.e., the " sulphonic sulphur." If the sulphur contained in the ammonium sulphate as previously determined in ichthyol is calculated, and the result subtracted from the " total sulphur " as previously determined, the remainder should repre- sent the sulphur present in the organic-sulphonic acids contained in the substance. If the " sulphonic " sulphur in icy thy ol as previously calculated is subtracted from the sulphur in the organic-sulphuric acids as previously calculated, the remainder should correspond to at least 5.5 per cent of " organic " (" sulphidic ") sulphur. Calcium Ichthyol is a derivative of ichthyol in which calcium is sub- stituted for ammonium. It is a brown, tasteless powder, insoluble in water, and containing 2.5 per cent of calcium. Ichthalbin. — Ichthyol Albuminate is a compound of ichthyol-sulphonic acid and albumin analogous to tannalbumin. It is a extremely fine, grayish-white powder, odorless and practically tasteless, insoluble in water, in the gastric juice, or in acid liquids, but completely soluble in alkaline liquids. Ferrichthyol is a brown-black permanent powder, nearly odorless and tasteless, containing 2.5 per cent iron. It is insoluble in the ordinary solvents, acids or alkalies. Tumenol Tumenol is a mixture of sulphones and sulphonic acids obtained from bituminous minerals and in the crude form is a blackish-brown liquid soluble in ether. Tumenolsulphone is that portion of the crude mixture which is extracted by ether after saponification. It is used in antiseptic ointments. The acid products obtained from the crude oil are solid and easily soluble in water. These materials are all used as antiseptics in skin diseases. BILE ACIDS Oxgall or bile both in its original condition and in a purified state is recognized by the U. S. Pharmacopoeia, and as a remedy is employed in gallstones, constipation, catarrhal jaundice, and other conditions of a diseased liver. The purified bile of the hog and other animals is also used medicinally. It is probable that the efficiency of these secretions 722 ORGANIC SUBSTANCES is due, at least in part, to the animal acids which they contain. These acids have been separated in a condition of greater or less purity and sold under various proprietary names for diseased conditions. Inspissated oxgall is prepared by straining fresh bile and evaporating to the consistency of a solid extract. Oxgall is combined with other chemicals in various mixtures intended as tonics for convalescents and for ansemics and consumptives. It will be found in admixture with hypophosphites in liquid preparations, with modified or so-called " metabolized " oils and with extracts of other animal secretions, spleen, testicles, etc. The purified bile is dispensed alone in pill, tablet, and capsule form. Some of the combinations include ginger, colocynth, pancreatin, pepsin, Nux Vomica; also shotgun prescriptions of some or all of them together and with perhaps the further addition of aloes, berberin, stramonium, quinin, and Taraxacum. Comparatively recent investigations have elucidated the composition of bile and demonstrated the presence of complex nitrogenous and nitro- genous sulphur acids. Some of these acids have been separated in a fair condition of purity, and a number of products have appeared on the market, the activity of which is credited to these acids. Glycocholic, C26H43O6N, and taurocholic acids, C25H45O7NS, occur in oxbile in the form of their sodium salts. They may be separated in the following manner. Dry oxbile is treated with absolute alcohol and the tincture precipitated by ether in excess. Both salts are deposited and the glyco- cholate crystallizes upon standing, the taurocholate remaining in amor- phous form, resembling oily or resinous matter. If the deposit is dis- solved in water, solution of lead acetate will throw down a lead glyco- cholate, while the addition of lead subacetate to the remainder will pre- cipitate the taurocholate. All the bile acids respond to Pettenkofer's test. A small portion of the salt is dissolved in a little concentrated sulphuric acid in a small por- celain dish and warmed, care being taken that the temperature does not rise higher than 60° to 70° C. A 10 per cent solution of cane sugar is then added drop by drop while the liquid is stirred with a glass rod. If compounds of cholic acid are present a beautiful red color will appear, which does not disappear at room temperature, but usually in the course of a day becomes bluish violet. The red liquid shows in the spectrum two absorption bands, one at F and the other between D and E near to E. Care must be taken not to heat too much nor to add too much sugar. The sulphuric acid must be free from sulphurous acid and the lower oxides of nitrogen. As albumin, oleic acid, amyl alcohol, morphin, etc., may give a similar reaction, spectroscopic examination should not be omitted in doubtful cases. ORGANIC ACIDS— AROMATIC SERIES 723 Furfurol Test (Myllus): The substance is dissolved in alcohol and for every mil of the alcoholic solution, one drop of a 1 : 1000 furfurol solution and one mil of concentrated sulphuric acid are added and the mixture cooled, if necessary, so that the temperature may not rise too high. The same color reaction occurs as in PettenkofTer's test. Both glycocholic and taurocholic acids generally undergo hydrolysis under the influence of dilute acids or alkalies. The former yields cholalic acid, C24H40O5, and glycocoll, C2H5O2N, and the latter cholalic acid and taurine, C2H7O3NS. Glycocholic acid, C23H39O3 • CO • NH • CH2COOH, forms glistening scales or needles which vary in melting-point from 132-152°, depending on the mode of preparation. It is slightly soluble in hot water and ether, readily soluble in alcohol and insoluble in chloroform and benzole. Taurocholic acid, C22H39O3CONH.CH2CH2— S0 2 OH, forms hygro- scopic silky needles, readily soluble in alcohol and water, insoluble in ether, benzol, and acetone. When heated, it contracts at 140° and begins to break up at 160°, forming a liquid at 180°. Its solution in water has the property of holding up glycocholic acid. Both acids are dextrorotatory. The amount of taurocholic acid may be estimated by calculation from the amount of sulphur contained in an alcoholic solution of the bile. /COOH Cholalic or cholic acid, C2oH3i^(CH-OH)o, crystallizes in the form of \CHOH rhombic plates or prisms with one molecule of water, or from alcohol in rhombic tetra- or octahedra with one molecule of the solvent. The crys- tals are very sparingly soluble in water and ether, but dissolve readily in alcohol. The alcohol molecule may be driven off by heating between 100-120°, and the acid melts 195°. The acid gives a blue compound with iodin. When added to 25 per cent hydrochloric acid at the ordinary temperature, a violet-blue color gradually develops, changing slowly to green and yellow. The blue solution shows an absorption band at D. Glycocholeic acid, C27H45O5N, and taurocholeic, C27H47O6NS, occur in bile. Hyoglycocholic acid, C27H43O5N, is obtained from pig's bile. Cheno-taurocholic acid is the chief taurocholic acid of goose-bile. Hyo- cholic acid, C25H44O4, and chenocholic acid, C27H44O4, are obtained by the hydrolysis of the conjugated acids of the bile of the pig and goose respectively. Oxbile itself may be described as a brownish or dark-green, some- what viscid liquid having a peculiar unpleasant odor and a disagreeable bitter taste. It has a specific gravity of 1.015-1.025 at 25° and is neutral or faintly alkaline. A small quantity of an aqueous mixture when treated with a crystal of sugar which is allowed to dissolve and afterward with a 724 ORGANIC SUBSTANCES drop or two of sulphuric acid cautiously added until the precipitate first found is redissolved will give a brownish color changing to carmine, purple, and violet. Attention should be directed to this reaction because it simulates that given by cod-liver oil and sulphuric acid, and both cod- liver oil or cod-liver extracts are dispensed with oxgall. Purified oxgall is virtually an alcoholic extract of bile. The albumin- oids present in the original secretion are mostly absent, but the bile acids, pigments, etc., are still present. It is completely soluble in water and alcohol and the aqueous solution is not precipitated by alcohol. The mixed salts of bile acids will be found on the market under various proprietary names, Colalin Colalin consists essentially of a mixture of hyoglycocholic and hyotauro- cholic acids, obtained from bile. To preserve the pulverulent condition a little magnesium carbonate is added. It is a yellow powder of faint odor and persistent bitter taste. It melts at 103 to 107° C, is slightly soluble in water, and acid toward litmus. Colalin should be readily soluble in alcohol and this solution should rotate polarized light to the right. It should dissolve almost entirely in a dilute solution of sodium carbonate with evolution of carbon dioxide and in a dilute solution of sodium hydroxide. The solution in sodium hydroxide should not be rendered turbid by the addition of barium hydroxide (absence of fatty acids). It should not contain more than a trace of sulphur (absence of taurin). This product which is usually sold in the form of tablets is recommended for the removal of gallstones, NUCLEIN, NUCLEIC ACID, AND NUCLEATES Nucleins are modified nucleoproteins obtained by peptic digestion or by treatment with dilute acids. They are split up by the action of alkalies or by tryptic digestion into a protein constituent and a nucleic acid vary- ing somewhat with the source of the nucleoprotein from which they are derived. The nucleic acids of commerce are apt to contain some protein in combination. They are most commonly made from yeast cells, but have been made, also, from the wheat embryo, the sperm of certain fishes and from the thymus and pancreas glands. In composition they approxi- mate the formula C40H52N14O25P4. From the wheat embryo products with relatively more nitrogen have been obtained. Nucleins are colorless, amorphous, insoluble in alcohol and ether and insoluble or slightly soluble in water. They are more or less readily dis- ORGANIC ACIDS— AROMATIC SERIES 725 solved by dilute alkalies. They give the biuret test and Millon's reaction. They show a great affinity for many dyes, taking them up from aqueous or alcoholic solutions. The term nuclein is sometimes used to designate an impure nucleic acid, which usage has led to confusion, as the nucleic acids are bodies of definite composition. Both nucleins and nucleic acids yield metaphosphoric acid on inciner- ation. On fusion with potassium nitrate and sodium carbonate they yield alkali phosphates. Nuclein and nucleic acid and nucleates are said to increase the number of white corpuscles, and it has been claimed that this increases the resist- ance to infection. Nuclein and nucleic acid and nucleates have been used in tuberculosis and various infections. The crude nuclein is separated from the yeast by bringing into solu- tion the albuminous substances and nuclein by means of an alkali, pre- cipitating the albuminous substances by adding acetic acid and heating to 75°, filtering and precipitating the crude nuclein from the filtrate by acidulated alcohol. It is purified by dissolving in water or weak alkali, adding dilute potassium permanganate, filtering, and again precipitating with acidulated alcohol. Another process consists in acting on yeast in presence of water at a temperature of 70-75° with sodium zincate, aluminate or similar metallate, acidifying with acetic acid, filtering, heating, and throwing out the sodium nuclein compound with alcohol. From this salt the nuclein is obtained by dissolving it in a little water and pouring into alcoholic hydrochloric acid solution. Pure nucleic acid is a white amorphous powder with an acid reaction readily soluble in water containing a little alkali, insoluble in alcohol and ether. From its solutions in alkalies, it may be precipitated by hydrochloric acid, but not by acetic acid. When chemically pure it does not give the biuret test or Millon's reaction, but the commercial article often gives a slight response to these reactions. It should contain between 14.5 and 16.5 per cent nitrogen and between 8.5 and 10.5 per cent of phosphorus. Nuclein is dispensed both in the solid condition and in capsules. The solutions usually contain about 5 per cent of nucleic acid. The metallic compounds of nuclein are prepared by adding solutions of the metals to an alkaline solution of the nuclein and precipitating the compound with alcohol. Cuprol is a copper compound containing about 6 per cent of the metal. It is a greenish powder soluble in water, and is used as an astringent alter- ative, its special field being in ophthalmic practice. Ferrinol, an iron nuclein compound, is a brown powder freely soluble 726 ORGANIC SUBSTANCES in water, containing about 6 per cent of iron and 4.5 per cent phosphorus combined in the nuclein. It is employed as a tonic and reconstructive. Mercurol is a mercury compound, a colorless or brownish- white powder containing 10 per cent of mercury, soluble in water with a weak alkaline reaction. It is used internally and locally as a substitute for mercuric chloride and is recommended for syphilis. Nargol is the silver compound of this series. It is a gonorrhea remedy and is recommended as a local application in all forms of diseases for which silver nitrate has been used. It is a light brownish-white powder, soluble in water and contains 10 per cent of silver. Complex compounds of silver are prepared by treating the crude nuclein with formaldehyde and subsequently obtaining the silver com- pound by treating a soluble salt with silver nitrate which is dissolved in a solution of some neutral salt, and reprecipitated in a soluble form by alcohol. Sophol Sophol is a compound of silver and methylenenucleinic acid, the silver being in the organic (" masked ") form. It is a yellowish powder, having a metallic taste and claimed to con- tain silver, equivalent to not less than 20 per cent metallic silver. It is readily soluble in water, the aqueous solution having a faint alkaline reaction; it does not give a precipitate on the addition of dilute solution of sodium hydroxide or of sodium chloride; it is insoluble in ether and alcohol. If .5 gram sophol is boiled with 5 mils of sodium hydroxide solution, the latter assumes a black color with the development of a formaldehyde odor. CHAPTER XIX ETHEREAL SALTS— PHENOLS ETHEREAL SALTS The alcohols combine with organic and inorganic acids to form a large class of substances known as ethereal salts or esters. Many of these bodies are of great importance in medicine. Some of them, like the ethereal salts of the halogen acids, are identical with the monohalogen substitution products of the hydrocarbons. The di-, tri- and higher sub- stitution products of the paraffins such as chloroform, CHCI3, are not strictly ethereal salts, but their analogy and relationship is so close that they are conveniently considered under this heading. We shall not undertake a description of all of these bodies, but will treat in full only those of interest to our work. The ethereal salts are in general neutral in reaction, unless in excep- tional cases only they may contain a free carboxyl or phenolic hydroxyl group. They are removable from acid or alkaline mixtures with immiscible solvents, and are hydrolyzed into 'their components by saponification with alcoholic potash. From the alkaline mixture the alcoholic portion can be separated by distillation or by shaking out with ether, and then on adding sulphuric acid, the acid constituent is freed, and may be recognized by appropriate tests, Methyl Chloride Methyl chloride, CH3CI, is the hydrochloric acid ester of methyl alcohol. It occurs, in the condensed state, as a colorless liquid, having an ethereal odor, and a sweet taste. Methyl chloride is insoluble in water, more readily in alcohol, freely in ether and chloroform, and also in acetic acid. At about -25° C. it has a specific gravity of .991, and boils at about —21° C. It burns in air with a greenish flame, though it is not highly inflammable. The neutral solution is not precipitated by solution of silver nitrate, nor is there any reaction with potassium iodide and starch paste. In the liquid condition, it is a powerful refrigerating agent. At very low temperatures it forms with water a hydrate, CH 3 C1-9H20. 727 728 ORGANIC SUBSTANCES It is used as a general anesthetic mixed with ethyl chloride and ethyl bromide. Methyl Iodide, CHJ Methyl iodide or iodomethane is a colorless, transparent liquid, which turns brown on exposure to the light. It boils 42° C, specific gravity 2.279 at 15° C. It is used as a vesicant and sometimes replaces cantha- rides in blistering compounds. Methyl Acetylsalicylate, C 6 H 4 (COCH 3 )OCOCH 3 This ester, known also as methyl rhodin and methyl aspirin, is a crys- talline solid, melting 54°, insoluble in water, but dissolving in alcohol, ether, glycerin, and oils. It is employed as an antineuralgic Methyl Benzoyl Salicylate Benzosalin is methyl benzoyl salicylate, CeH4- (XCH3) • COO(C6H 5 CO), 1 : 2 the benzoyl salicylic acid ester of methyl alcohol. Benzosalin is prepared by a reaction between the methylester of salicylic acid and benzoyl chloride in the presence of sodium hydroxide. Benzosalin consists of fine, white crystals with a very faint aromatic odor. It melts at about 85° C. It dissolves readily in chloroform, ben- zene, and in 35 pans of 90 per cent cold alcohol, also in pure concentrated sulphuric acid. Benzosalin passes the stomach unchanged and is decomposed into its constitutents, benzoic, and salicylic acid in the intestines. It is said to be useful in rheumatic affections, such as arthritis, neuralgia, sciatica, and migraine, and in arthritis deformans. Methyl Salicylate Methyl salicylate has been fully discussed in connection with the chem- istry of salicylic acid, page 687. Methyl Gallate, C 6 H 2 (OH) 3 COOCH3 Methyl gallate or Gallicin forms grayish-white crystals, melting 192- 202°, depending on its purity, soluble in water, alcohol, and ether. It is used as an antiseptic in eye troubles and as an anticatarrhal. Methylenedimethyl Ester, CH 2 (OCH 3 ) 2 Methylal, formal, or methylenedimethylate is a colorless volatile liquid with an odor resembling chloroform. Its specific gravity is .855 at 15°, it boils 42° C and it is readily soluble in water, alcohol, and oils. ETHEREAL SALTS— PHENOLS 729 It has anesthetic, hypnotic, and anodyne properties, and is used in delirium tremens, insomnia, strychnin poisoning, acute gastric and intes- tinal indigestion. When dispensed as a local anesthetic it is usually in an ointment or liniment. Methylene Dichloride, CH 2 C1 2 Methylene dichloride is an anesthetic resembling chloroform in its odor but boils at 40° and has a specific gravity of 1.377. It burns with a smoky flame and dissolves iodin with a brown color. Mixtures of chloroform and alcohol are sometimes substituted for methylene dichloride, but the fraud is easily detected if the sample is diluted with water, and the precipitated heavy liquid tested for its specific gravity and boiling-point. Ethyl Chloride, C 2 H 5 C1 Ethyl chloride or hydrochloric ether is also known by several commercial names, e.g., kelene. It is used for general anesthesia by inhalation and as a local anesthetic. It is a colorless, mobile liquid with a penetrating, pungent somewhat fragrant odor, boiling 12.5°, specific gravity .851 at 12° C, very volatile and inflammable, burning with a smoky green-edged flame and producing vapors of hydrogen chloride. It is slightly soluble in water, readily in alcohol and ether, and dissolves phosphorus, sulphur, fats, and oils. It combines with some of the metallic chlorides such as antimony penta- chloride, and ferric chloride, to form crystalline compounds. Baskerville 1 states that ethyl chloride intended for anesthetic purposes should have the following characteristics : 1. Its boiling-point should be +12.5°. 2. On allowing 30 mils to evaporate from a 12J cm. filter paper, no foreign or unpleasant odor, especially a garlic odor (indicating phosphorus compounds) should be apparent either during or subsequent to evapor- ation. 3. Sixty mils when allowed to evaporate spontaneously should leave no weighable residue. 4. On shaking 10 mils with 10 mils water at 10° C, and then allowing the ethyl chloride to evaporate, no odor of acetaldehyde should develop on adding 3 drops of potassium bichromate followed by 5 drops of dilute sulphuric acid and boiling, nor should a bluish or greenish color develop. 5. Ten mils dissolved in 10 mils 95 per cent alcohol should give no turbidity or precipitate with 3 drops silver nitrate. 1 J. Ind. and Eng. Chem., 1913, 5, 828. 730 ORGANIC SUBSTANCES The presence of ethyl chloride must be declared on the label of a pack- age containing it, as it is a derivative of alcohol. Its assay quantitatively is not a simple matter, because it must be saponified under pressure and there is so much gas developed that the ordinary form of pressure flask will not stand the strain. The result may be accomplished, by using a Carius tube, and heating the mixture at the temperature of the water-bath. The little ampules should be scratched with a file at a point where they may be broken with comparative ease when subjected to concussion, and then introduced into the tube, followed by alcoholic potash. The tube can then be sealed off, the ampule broken by concussion, and after heating, the end of the tube is broken, the liquid washed out, the alcohol evaporated, and the chlorine determined by silver precipitation. Polychlorated ethyl chloride, or Wigger's anesthetic ether, is a mix- ture of tri-, tetra- and pentachlorethane. It has an ethereal aromatic odor suggestive of camphor, and is used as an anesthetic and irritant. It is used chiefly in rheumatic conditions and neuralgia. Ethyl Bromide Ethyl bromide, C2H5Br, is the hydrobromic acid ester of ethyl alcohol containing approximately 1 per cent ethyl alcohol. It is a colorless, strongly refractive, easily volatile liquid, having a pleasant ethereal odor. It is insoluble in water, but readily soluble in alcohol and in ether. It boils at from 38 to 40° C. Its specific gravity at 15° is 1.453 to 1.457. It is stable when pure but when contaminated with ethyl iodide it becomes colored when exposed to light. It burns with difficulty. It is very difficultly saponified by potassium hydroxide and it is not attacked by sulphuric or nitric acids. Silver nitrate gradually precipitates silver bromide. If a mixture of 1 mil ethyl bromide, 5 mils alcohol and 10 drops of 15 per cent sodium hydroxide solution is heated to boiling, cooled, acidified with dilute sulphuric acid then shaken with chloroform and chlorine water added, a brown coloration will be produced in the chloro- form layer. If equal volumes of ethyl bromide and sulphuric acid are shaken together in a bottle previously rinsed with sulphuric acid and closed with a glass stopper, the acid should not be colored yellow within an hour. After shaking equal volumes of ethyl bromide and water, no change of volume should occur in the two liquids, the water separated from the ethyl bromide should not have an acid reaction nor should it become turbid immediately on the addition of a drop of silver nitrate solution. When a small portion is evaporated from a porcelain plate by cau sing- it to flow to and fro over the surface little or no foreign odor is yielded as ETHEREAL SALTS— PHENOLS 731 the last portions pass off, and the plate is covered with a slight deposit of moisture. One mil of ethyl bromin mixed with 3 drops of anilin and 2 mils of alcoholic solution of potassium hydroxide should not give off the odor of isonitrile even after warming. (Absence of chloroform.) About 1 gram of ethyl bromide accurately weighed added to 30 mils of 80 per cent alcohol containing 2 grams silver nitrate will precipitate, after several hours, silver bromide, which when washed and dried should weigh 1.72 grams for each gram ethyl bromide used. Ethyl bromide is a rapid anesthetic, acting much like chloroform. Ethyl Iodide, C 2 H 5 I Monoiodomethane or hydriodic ether is a clear, colorless neutral liquid becoming brown on standing. It boils 70 to 75°, specific gravity 1.94 at 15°, soluble in alcohol and ether but insoluble in water. It is employed as an antispasmodic, anesthetic, stimulant, and alterative, and is recommended in chronic rheumatism, scrofula, syphilis, bronchitis, and asthma. It is given internally and in the form of an ointment. Ethyl Lactate, C 3 H 5 3 C 2 H 5 Lactic ether is a colorless limpid liquid, sp. gr. 1.031 at 19° C, boiling 154° C, and soluble in water. It is employed as a sedative and hypnotic. Ethylene Dichloride, CH 2 C1CH 2 C1 Ethylene chloride or Dutch liquid is, strictly speaking, an addition product of the unsaturated lrydrocarbon ethylene, and is prepared by direct union with chlorine. It is a colorless oily liquid with pleasant odor and sweet taste, specific gravity 1.265 at 15° C, boiling 83 to 85°; its vapors are irritating to the membranes. It is soluble in alcohol, ether, and chloroform, and slightly in water. It is used as a substitute for chloroform as an anesthetic, and externally is employed in rheumatism. Monochlorethylene Chloride, CH 2 C1CHC1 2 This product, also known as ethylene chloride, monochlorinated Dutch liquid, and vinyl trichloride, is a colorless liquid, having a pleasant odor, sp. gr. 1.458 at 9° C, boiling 114° and soluble in alcohol and water. It is used as an anesthetic in place of chloroform. Ethylidene Chloride, CH 3 CHC1 2 Ethylidene chloride is isomeric with ethylene dichloride. It is also termed chlorinated muriatic ether, alphadichlorethane, ethidene bichloride, 732 ORGANIC SUBSTANCES and chloridene. It is a colorless, oily liquid with a chloroform odor, sp. gr. 1.178 at 15° C, boiling 58-60° C, and used as an anesthetic and analgesic. Ethyl Nitrite, C 2 H 5 NO a Ethyl nitrite or nitrous ether is known only in the form of the spirit of nitrous ether or sweet spirit of niter. The spirit is yellowish in color and has a fragrant, pungent odor. The official article contains not less than 4 per cent of the ester in alcoholic solution, and has a sp. gr. of .823 at 25° C, soluble in water and alcohol. It is also sold in a concentrated form which can be readily diluted with alcohol to the official strength. Ethyl nitrite spirit is employed as a diaphoretic, stimulant, diuretic, antipyretic, and antispasmodic. It is used in fevers, colds, dropsy, colic, nausea, and genito-urinaiy troubles, and is almost always dispensed alone, but for dropsical complaints may be found mixed with squill, Digitalis, potassium acetate, or potassium nitrate. For certain states of febrile conditions it is mixed with aromatic spirit of ammonia. Absolute ethyl nitrite is pale yellow, boiling 17-18° C, with sp. gr. .917 to .920 at 0°. The assay of spirit of nitrous ether may be accomplished by the same procedure as is described under Amyl Nitrite. Factor for Ethyl Nitrite, 3.07. Ethylene Dibromide, CH 2 BrCH 2 Br Ethylene dibromide or dibromethane is formed by the direct union of bromin and ethylene. It is a colorless crystalline substance below 9° C. but is usually encountered as a colorless liquid with a chloroform odor, sp. gr. 2.189 at 15° C, boiling 129-131° C, miscible with alcohol, but insoluble in water. It is used in epilepsy and neuralgia, but in small dosage as it is quite toxic. Ethyl Acetate, CH 3 COOC 2 H 5 Ethyl acetate or acetic ether is a colorless fragrant inflammable liquid, boiling 72-77° C, miscible in all portions with alcohol and ether and with 17 parts of water. The official grade contains about 10 per cent of alcohol and a little water. Ethyl acetate is sometimes used internally in nervous affections and to revive one after fainting. Externally it is used to a limited extent as an anesthetic and antirheumatic. The odor of ethyl acetate is characteristic and the formation of this substance recognizable by its odor, is used as a test for acetic acid. ETHEREAL SALTS— PHENOLS 733 Ethyl Benzoate, C 6 H 5 COOC 2 H5 This ester is not used medicinally, but it plays an important part in analytical chemistry, as its formation as determined by its odor, is used as a test for cocain. It is volatile at all temperatures and boils 212-213° C. Ethyl Cinnamate Ethyl cinnamate occurs in storax; sp. gr. 1.0531, boiling 257-258°. Ethyl Diiodosalicylate, C6H 2 l2(OH)COOC 2 H5 Diiodosalicylic ether forms white crystals, melting 132°, soluble in alcohol and fixed oils and slightly in water. It is used in surgery as a substitute for iodoform. Ethyl Formate, HCOOC 2 H 5 Ethyl formate is a mobile, colorless liquid with a peach-kernel odor, sp. gr. .917 at 15° C, boiling 54°, miscible in all proportions with alcohol and ether and with 9 parts of water. It is used as an hypnotic and analgesic. True ethyl formate must not be confused with a substance known as " orthoformic " ether, CH(OC2H5)3, which is prepared from chloroform and sodium ethylate. This product is a colorless, aromatic liquid, boiling 145-146° C. Ethyl Thiocarbimide, C 2 H 5 NCS Ethyl mustard oil is a colorless, pungent liquid, very irritant to the tissues and used externally as a local irritant in rheumatism, neuralgia and local pains. It boils 133° C. Ethyl Valerate, (CH 3 ) 2 CHCH 2 COOC 2 H 5 Isovaleric ether is a colorless liquid with a pleasant fruity odor, sp. gr. .871 at 15° C, boiling 134° C. It is used as a sedative and anti- spasmodic in nervous affections, especially asthma. Amyl nitrite is the isoamyl ester of nitrous acid. It is a yellow, trans- parent, very mobile, volatile, inflammable liquid having a penetrating characteristic odor, and a stimulating effect on the senses. Its sp. gr. is .870 to .880 at 15° or .865 to 875 at 25°, boiling 97 to 99°, evolving an orange-colored vapor, volatile at all temperatures, insoluble in water, 734 ORGANIC SUBSTANCES but dissolving in all the organic solvents. The ester deteriorates rapidly, and is usually dispensed in small hermetically sealed glass bulbs. The commercial nitrite is probably contaminated with the nitrites of other higher alcohols, and furthermore the amyl radicle may be attrib- uted to more than one isomeric form. Assay, U. S. P. Method. — Transfer about 3 mils of Amyl Nitrite, which has been previously shaken with .5 gram of potassium bicarbonate and carefully decanted, to a tared 100-mil measuring-flask, containing about 20 mils of alcohol, and weigh it accurately. Add sufficient alcohol to bring the volume to exactly 100 mils and mix thoroughly. Introduce into a nitrometer exactly 10 mils of the alcoholic solution, followed by 10 mils of potassium iodide T. S., and afterward by 5 mils of diluted sul- phuric acid. When the volume of gas has become constant (within thirty to sixty minutes), note the amount collected, multiply this volume in mils by 4.8 and divide the product by the original weight in grams of the Amyl Nitrite. At standard temperature and pressure, the quotient represents the percentage of Amyl Nitrite in the liquid. The temperature correction is one-third of 1 per cent of the total percentage just found for each degree — additive if the temperature is below 25° C, and sub- tractive if it is above 25° C. The barometric is four-thirtieths of 1 per cent of the total percentage just found for each millimeter — additive if it is above 760 mm. and subtractive if it is below 760 mm. Assay, Modification of the U. S. P. Method. — Use a saturated salt solution in the nitrometer. Weigh the amyl nitrite in a closed container and add 13 drops to about 2 mils of alcohol in the upper tube of the nitrometer and admit to the nitrometer tube. Wash out upper tube with 5 mils of alcohol. Then add a mixture of 10 mils of potassium iodide solution (1 : 10) and 10 mils N/1 sulphuric acid. Allow reaction to cease before taking the reading of the NO. Compute this reading to normal pressure and temperature. Weigh 1 mil NO at N.P.T. = . 001306 gram. From this the amount of amyl nitrite can be calculated. If one is in any way familiar with drug products the physical proper- ties of amyl nitrite are sufficient evidence for its detection. It is a powerful cardiac stimulant and antispasmodic and is used by inhalation or in capsules for whooping cough, angina pectoris, asthma, tetanus, epilipsy, syncope, chloroform asphyxia, etc, Amyl Bromide, C 5 H u Br Amyl bromide is a clear, Colorless liquid, sp. gr. 1.219 at 15°, boiling 120 °C, soluble in alcohol and used as a germicide and antiseptic. ETHEREAL SALTS— PHENOLS 735 Amyl Iodide, C 5 HnI Amyl iodide is a yellowish liquid, sp. gr. 1.48 to 1.50 at 150° C, boiling 140 to 148° C, soluble in alcohol, used as a sedative and antiseptic. Amyl Salicylate, C 6 H 4 OHCOOC 5 Hii Amyl salicylate is a colorless or yellowish liquid, sp. gr. 1.055 to 1.065 at 15° C, boiling 263-265° C, soluble in alcohol, ether, and chloroform and insoluble in water. It is used both internally and externally as an antirheumatic. Amyl Valerate Amyl valerate, CH3 • CHCCHa) ■ CH 2 ■ COCKCH3) • CH 2 • CH 2 ), is the iso- valeric acid ester of iso-amyl alcohol. It is obtained by separating (by distillation) the ester which is formed when valeric acid or soluble valerate is added to a mixture of iso-amyl alcohol and sulphuric acid and the distillate obtained, washed, dried, and redistilled. Amyl valerate is a colorless liquid, having when dilute an odor of apples. It is insoluble in water, soluble in alcohol, ether, and chloroform. It boils at 188 to 190° C. Its sp. gr. is .858 at 15° C. Amyl valerate has been employed in the treatment of gallstone colic. Amylene, (CH 3 ) 2 C = CHCH 3 Amylene, trimethylethylene, or pental is a colorless, mobile inflammable liquid, with a disagreeable odor, sp. gr. .666 at 15° C, boiling 35-38° C, miscible with alcohol and ether, insoluble in water. It is used as an anesthetic in dental surgery. Dimethylacetal, CH c CH(OCH 3 ) 2 Dimethylacetal or ethylidenedimetlvylester is a colorless liquid, specific gravity .879 at 0°, boiling 62-63°, miscible with water and the organic solvents, and employed as an anesthetic as a substitute for chloroform. Carbosant Carbosant is santalyl carbonate, (C15H23) -O-COO- (C15H23), the car- bonic acid ester of santalol. It is an oily yellow fluid, almost tasteless and odorless, insoluble in water, and soluble in alcohol and ether. It contains 94 per cent of san- talol. 736 ORGANIC SUBSTANCES Carbosant is saponified when heated with an alcoholic solution of caustic alkali with the production of potassium carbonate and santalol. Carbosant is employed in the treatment of gonorrhea, cystitis, and prostatitis. Nitroglycerin, C JI d (ON0 2 )3 Nitroglycerin, glyceryl trinitrate, propenyltrinitrate, or glonoin, is used in medicine as a remedy in angina pectoris. Its presence may be expected in remedies for heart troubles. It is commonly prepared for administra- tion in the form of tablet triturates and pills containing from 10 1 00 to ■^o grain, and it is also mixed with Strophanthus or Digitalis, or both and occasionally with strychnin, spartein, Cactus grandiflorus, belladonna, and caffein. Spirit of glonoin is a pharmacopceial product and contains 1 per cent of nitroglycerin in alcoholic solution. Nitroglycerin itself is a colorless or yellowish oil with a sweetish taste, sp. gr. 1.6, soluble in ether, sparingly in alcohol, and insoluble in water. It may be hydrolyzed by boiling alkalies, yielding glycerin and a nitrate, together with a small amount of nitrite owing to secondary reac- tions. On reduction with ammonium sulphide it yields glycerin, ammonia, and free sulphur. Much work has been done on the assay of nitroglycerin tablets, and after an extended study Murray of the Bureau of Chemistry has recom- mended the following tests: Methods for the Determination of Nitroglycerin in Medicinal Tablets. — Preparation of the sample. — Crush 25 tablets under 10 mils of ether. A 25-mil cylindrical graduate makes a convenient container and a stout glass rod is used to crush the tablets. Rinse the rod with a little ether, allow the insoluble material to settle and decant the solution into a 50- mil graduated flask. No special care need be taken to prevent a little insoluble material from going into the flask. Wash the residue repeatedly with 5-mil portions of ether and decant the washings into the flask until it has been filled to the mark. Insert the stopper and mix well. Estimation by the Modified Scoville Method. — Place 20 mils of the ethereal solution in a carefully dried and tared 50-mil beaker. (A second aliquot of 10 mils may be used as a check.) Evaporate the solvent in a vacuum desiccator. Apply the vacuum gradually so as to prevent ebulli- tion. Leave the beaker in the vacuum thirty minutes after the ether has evaporated. Weigh and calculate ether extract per tablet. Treat the residue with 2 mils phenoldisulphonic reagent, rotating the beaker in such a way that the reagent comes into contact with the entire inner surface. After ten minutes add water and wash into a 100-mil flask. (If a check analysis as suggested was made, wash this into a 50-mil flask.) ETHEREAL SALTS— PHENOLS - 737 Dilute to the mark and place 10 mils, representing 1 tablet, in a 100-mil flask, add about 50 mils water and a few drops more potassium hydroxide solution (20 per cent) than is required to neutralize the acid. (Do not use sodium hydroxide.) Dilute to the mark and compare the color with that produced by a standard nitrate solution similarly treated. Use any convenient colorimeter or Nessler tubes. Reagents and Standards. — Phenoldisulphonic Acid Reagent. — Dis- solve 25 grams of pure white phenol in 150 mils of concentrated sulphuric acid, add 75 mils of fuming sulphuric acid (13 per cent SO3), stir well, and heat for two hours at about 100°. Standard Solution. — Dissolve .7217 gram pure KNO3 in 1 liter of water. Evaporate 10 mils of this solution just to dryness on the steam- bath. Cool and treat the residue with 2 mils phenoldisulphonic acid reagent, observing the precautions noted above and using a glass rod if necessary to aid the solution of the residue. After five or ten minutes dilute to 250 mils. Each mil of this solution contains .004 mg. nitrogen. Add an excess of KOH solution to an aliquot of this solution and dilute to 100 mils. It is advisable to prepare a standard of approximately the same color as the unknown. Nitroglycerin is 5.4 times nitrate nitrogen. Estimation by the Modified Hay Method. — Place 5 mils of the ethereal solution in a 50-mil beaker, dilute with 5 or 10 mils alcohol and add about 5 mils of J per cent alcoholic potassium hydroxide. Cover with a watch- glass and allow to stand ten minutes. Place on a steam-bath, allow to boil, remove the watch-glass, and when most of the liquid is evaporated add about 25 mils water and leave on steam-bath until about half the liquid has evaporated or until the odor of alcohol can no longer be detected. Cool and dilute to 250 mils. Each mil of this solution represents .01 of a tablet. Introduce an aliquot representing .02 to .04 milligram nitro- glycerin into a 100-mil graduated flask, dilute with sufficient water to make the volume 90 to 95 mils, add 1 drop concentrated hydrochloric acid, then 2 mils sulphanilic acid solution and 2 mils naphthylamine hydrochloride solution. Complete the volume with water. Prepare at the same tune and in the same way standards containing known amounts of sodium nitrite. Stopper the flasks and mix well. Compare the colors after thirty minutes. Nitroglycerin is calculated by multiplying nitrogen found by 8. Reagents and Standards. — Sulphanilic Acid Solution. — Dissolve 1 gram in 100 mils hot water. Naphthylamine Hydrochloride Solution. — Under a hood boil .5 gram of the salt with 100 mils water for ten minutes, keeping the volume constant. Filter and keep in a glass-stoppered bottle. Standard Solution of Sodium Nitrite. — To a cold solution of about 2 grams of sodium or potassium nitrite in 50 mils of water, add a solution 738 ' ORGANIC SUBSTANCES of silver nitrate as long as a precipitate appears. Decant the liquid and thoroughly wash the precipitate with cold water. Dissolve in boiling water. On cooling the silver nitrite is precipitated. Dry the crystals in the dark at the ordinary temperature (preferably in a vacuum). Weigh out 220 mg. of the dry silver nitrite, dissolve in hot water and decompose with a slight excess of sodium chloride. When the solution becomes clear, dilute to 1 liter. Dilute 5 mils of this solution to 1 liter. This second dilution is the standard to be used. It contains .0001 mg. nitrite nitrogen per mil. Only nitrite free water should be used in the estimation by the modified Hay method. Erythrol Tetranitrate Tetranitrol, C4He(N03)4, is the tetranitrate of erythrite (butane- tetrol), C 4 H 6 (OH) 4 . It forms colorless crystalline scales, insoluble in cold water, readily soluble in alcohol, melting at 61° C. (141.8° F.) On percussion it ex- plodes much like nitroglycerin. It is employed in angina pectoris and vascular diseases. Nitroglucose Nitroglucose is an explosive substance obtained by the action of nitric and sulphuric acid on glucose. It is marketed in either an alcoholic or aqueous solution of about 5 per cent strength, and is used in epilepsy, angina pectoris, and cardiac weakness. CHLOROFORM, CHC1 3 Chloroform is used to a considerable extent as an anesthetic for inha- lation, as a counter-irritant, a narcotic, and analgesic. For internal use it will be found in remedies for flatulent colic, gastralgia, asthma, cough, spasms, hysteria, hiccoughs, scarlet fever, insomnia, and for removing gallstones. Externally it is administered in the form of liniments for rheumatism, neuralgia, colic, etc., and hypodermically for hydrocele. Chloroform is also used to a limited extent in some of the artificial flavors used in foods. The general run of cough mixtures contain in addition to the chloro- form, white pine. bark, wild cherry, sassafras, Sanguinaria, spikenard, balsam poplar buds, eriodictyon, and sometimes morphin; or sometimes this may be varied by substituting codein and Cannabis indica. Com- pound tincture of opium or diarrhea mixture contains opium, camphor, Capsicum, and chloroform. Chloranodyne and preparations of the chloro- dyne type contain chloroform with morphin, Cannabis, hydrocyanic ETHEREAL SALTS— PHENOLS 739 acid, Capsicum, and peppermint. Chloroform is employed to a con- siderable extent in throat lozenges. Spirit of chloroform also called chloric ether, consists of about 10 per cent of chloroform and 90 per cent of ethyl alcohol by weight. Chloro- form water or aqua is official in some of the pharmacopoeias, and is a saturated aqueous solution of chloroform. Emulsions of chloroform are made with tragacanth, oil of almond, egg yolk, sometimes with the addi- tion of camphor. Chloroform hniment is prepared with about 70 per cent of soap hniment and 30 per cent of chloroform. Chloroform is a colorless, heavy mobile liquid with a characteristic odor. Its sp. gr. is 1.49887 at 15° C. and it boils at 60 to 61°, according to Baskerville. The anesthetic chloroform on the American market runs in specific gravity from 1.4730 to 1.4827 at 25° C. It is not inflam- mable, but its heated vapor burns with a greenish flame. It is only slightly soluble in water, but is miscible with alcohol and ether, and it is an excellent solvent, dissolving many of the alkaloids, resins, fats, gutta percha, caoutchouc, balsams, gum chicle, etc. Chloroform is readily decomposed by warm alcoholic potash, yielding potassium formate and chloride. It gives the carbylamine reaction when treated with anilin and alcoholic potash. When brought in contact with a solution of alpha- or beta-naphthol in strong potassium hydroxide and heated to 50° C. a fine blue color is developed, changing in contact with air to blue green, green, green brown and brown. The specifications for chloroform intended for anesthetic purposes have been laid down by Dr. Baskerville x as follows: 1. When 100 mils are evaporated over the steam-bath until 10 mils remain and the last portions are then allowed to evaporate spontaneously from a piece of filter paper, there should result no odor of fusel oil, empyreu- matic matter, or other substances than chloroform and alcohol. 2. One hundred mils should leave no weighable residue on evaporation. 3. When 20 mils are mixed with 15 mils of concentrated sulphuric acid in a glass-stoppered tube of 50 mils capacity previously rinsed with concentrated sulphuric acid, no visible coloration should be imparted after the addition of .4 mil of pure 40 per cent formaldehyde solution, and then shaking thoroughly for five minutes. (Test for organic impur- ities.) 4. When 20 mils of the sample are boiled over 1 gram of clean crystals of calcium carbide, and the vapors evolved are passed into ammoniacal silver nitrate solution, no acetylene reaction should result. Absence of water. 5. Anesthetic and commercial chloroforms will contain a small quantity of alcohol. If it is desired to test for alcohol in a product of higher purity i J. Ind. and Eng. Chem., 4, 1912, 576. 740 ORGANIC SUBSTANCES than the above mentioned, 10 mils are shaken in a separatory funnel with 4 mils of concentrated sulphuric acid, the treatment repeated, and a third time with 2 mils. The acid solution is then mixed with 40 mils of water and the dilute solution gently distilled until 20 mils have passed over. Ten mils of the distillate are treated with 6 drops of 10 per cent potassium hydroxide, warmed to 50° C, a saturated solution of iodide in potassium iodide added drop by drop, with agitation until the liquid becomes perma- nently yellowish brown in color, when it is carefully decolorized with potas- sium hydroxide. No iodoform should be deposited. This test is not peculiar to alcohol, being produced also by acetaldehyde, propyl alcohol, acetone, etc., but pure chloroform should give a negative test. 6. Pure chloroform complying with the iodoform test is free from acetone. Anesthetic chloroform should give a negative test when the following procedure is applied: Ten mils of the sample are agitated with 5 drops of .5 per cent sodium nitroprusside and 2 drops ammonium hydrox- ide (sp. gr. .925) and the mixture allowed to stand for several minutes. Chloroform containing up to 1 per cent of alcohol may impart a yellowish- brown color to the supernatant liquid on agitation, but when acetone is present an amethystine color results. The test must be conducted in the cold. After application to the suspected chloroform direct, the first 10 per cent distillate and the 10 per cent residuum obtained by allowing 100 mils of the sample to distill slowly should be tested. When the proportion of acetone to chloroform is 1 : 500, the amethyst color is marked, but in the presence of 1 : 1000 the coloration is not distinct until the whole mix- ture has been saturated with ammonium sulphate, shaken, and allowed to rest for five minutes. It is advisable to run a blank test on pure anes- thetic chloroform for comparison. Some acetaldehyde is generally present in fresh and properly stored samples of anesthetic chloroform in portions greater than 1 : 3300; usually the reaction is not interfered with by this substance, but in every case the sample should be examined for the presence of acetaldehyde and if it complies with test 7(a) below, a positive reaction upon applying the acetone test may be said to be solely indicative of acetone. 7. The presence of 3 parts of acetaldehyde by volume in 1000 parts of chloroform may be detected by the following reaction and smaller amounts by resorting to fractionation, and chloroform of all grades should comply with the test (a). (a) Five mils of the sample are agitated with 5 mils of there agent of Francois (20 mils of sulphurous acid, 30 mils 1 : 1000 rosanilin acetate solution and 3 mils sulphuric acid) in a glass-stoppered tube; no color- ation should result even after fifteen minutes. (6) Pure chloroform giving a negative reaction in Test 5 may be ETHEREAL SALTS— PHENOLS 741 regarded as free from acetaldehyde; but it should also give no response when 5 mils are agitated with 5 mils Nessler's reagent, U. S. P. and the mixture allowed to stand five minutes. When 10 mils of anesthetic chloroform are agitated with 10 mils of water and 5 drops Nessler's reagent U.S. P., and the mixture then allowed to stand for five minutes, there should result no precipitate and the reagent should assume no coloration, though it may become opalescent or slightly turbid. 8. When 20 mils of either pure or anesthetic chloroform are thoroughly agitated with 10 mils of water and 2 drops of phenolphthalein solution, and then titrated with N/100 potassium hydroxide solution, added drop by drop, not more than .2 mil of standard alkali should be required to produce a faint but decided alkaline reaction permanent for fifteen minutes, when the mixture is shaken for thirty seconds after the addition of each drop of alkali. 9. The following tests are conducted in order to detect the decompo- sition products of pure chloroform: (a) Carbonyl Chloride. — To 15 mils of the sample contained in a 25- mil dry glass-stoppered tube, sufficient of a perfectly clear 1 : 19 barium hydroxide solution is added to fill the tube. After allowing the mixture to stand three hours in a dark place without agitation, the observation as to the formation of a film of barium carbonate is made. (b) Hydrochloric Acid and Chlorides. — Samples complying with 8 are assuredly free from carbonyl chloride, hydrochloric acid and chlorine, but pure and anesthetic chloroform should also comply with the following test: When 10 mils of the sample are agitated with 5 mils of water for five minutes the water extract should not become turbid or give any precipitate on adding silver nitrate solution (absence of hydrochloric acid or chlorides) and no reduction should occur on warming (absence of acetaldehyde, formic acid and formates) . (c) Chlorine and Hydrogen Dioxide. — When 10 mils of the sample are agitated during fifteen minutes with 10 mils of a 10 per cent cadmium potassium iodide solution no iodin should be liberated, as determined by the addition of starch solution. Chloroform of all grades should give a negative reaction with this test. 10. The decomposition products of anesthetic chloroform. (a) The detection of acetaldehyde has been referred to in 7. (b) Anesthetic chloroform failing to comply with 8 should be rejected. (c) When 20 mils of the sample are shaken during twenty-five minutes with 15 mils of concentrated sulphuric acid in a 50-mil glass-stoppered tube previously rinsed with sulphuric acid, and 2 mils are diluted with 5 mils of water, the liquid should remain colorless and clear and should possess no odor foreign to anesthetic chloroform; and the liquid should 742 ORGANIC SUBSTANCES retain its transparency and colorless state when further diluted with 10 mils of water and the transparency should not be diminished on adding 5 drops of silver nitrate solution. Detection and Estimation of Chloroform. — As chloroform is one of the inhibited drugs, its presence in medicinal preparatioms and in food prod- ucts must be declared on the label. In many cases the characteristic odor will indicate that chloroform is present, but of course in others it will be masked by more powerful odors, and the peculiar cooling effect which it imparts on inhalation may be confused with that given by menthol. From liquid mixtures chloroform may be obtained by distillation and on diluting the distillate sufficiently if alcohol is present, the chloroform will settle out in the bottom of the flask. By distilling with steam, this procedure may be made approximately quantitative. The heavy liquid which has settled out should be tested further by applying the phenyl isocyanide test, and determining its boiling-point. Chloroform boils 60 to 61°, bromoform 148 to 150°, and carbontetrachloride 76 to 77°. The latter does not give the phenylisocyanide test. Chloroform can be determined when it occurs in liquid products by distilling into a flask, diluting the distillate with water if much alcohol is present, and decanting most of the supernatant liquid. The chloroform is then treated with 15 to 25 mils of N/1 alcoholic potash and boiled for one to two hours under a reflux. The chlorine is then determined by precipitating with silver nitrate in presence of nitric acid and the chloro- form calculated. With some distillates it might be more desirable to add the alcoholic potash without previous dilution and decantation. Dowzard's x method for the determination of chloroform in lozenges is as follows: A weighed lozenge is digested with 70 mils alcoholic potash in a 200-mil flask with reflux condenser, warming until dissolved and then gently boiling forty-five minutes. Twenty-five mils of water are added and a few drops of phenolphthalein, the solution acidified with nitric acid and then neutralized with calcium carbonate. After cooling the chlorine is titrated with silver nitrate solution, using potassium chromate. A blank may be run, using the same quantities of reagents without the lozenge, and the difference in amount of chlorine calculated to chloroform. Patents have been obtained for a " solid " chloroform w r hich is pre- pared by mixing the substance with peptone and allowing the excess to evaporate. 1 Am. J. Pharm., 80, 1909, 511. ETHEREAL SALTS— PHENOLS 743 Bromoform, CHBr 3 Bromoform, tribromomethane, methenyl tribromide, also called "formyl tribromide," is a heavy colorless liquid with an odor resembling chloroform. Its sp. gr. is 2.829 to 2.833 at 15° C,, or 2.808 at 25° C, boiling 148 to 150 and solidifying 6° C. It is soluble in alcohol and ether, somewhat in glycerin, and almost insoluble in water. It is not used to any great extent, but is an anesthetic, nervine, and sedative, and is employed chiefly in whooping cough. It gives the phenylisocyanide test, but its high specific gravity and boiling-point distinguish it sharply from chloroform. Brometone. Tribrom-Tertiary-Butylalcohol — Acetone-Bromoform Brometone, CBr3-C(OH)(CH3) -CH3, is produced by the reaction of acetone on bromoform in the presence of caustic alkalies. It occurs in fine white, prismatic crystals melting 167°, which possess a camphoraceous odor and taste. It is slightly soluble in water, soluble in alcohol, ether, benzine and most organic solvents. Brometone is claimed to have the sedative action of the bromides without the disadvantages of producing bromism. Trichlorisopropyl Alcohol. CC1 3 • CH = CH 3 OH This substance, known as Isopral, occurs in prismatic crystals, with a camphoraceous odor and pungent taste, melting 49° C, soluble in water, alcohol, and ether. It is employed as an hypnotic and as a substitute for chloral. In its appearance and organoleptic properties it bears a close resemblance to chloretone. Fluoroform, CHF 3 Fluoroform is dispensed in an aqueous solution containing about 3 ' per cent of the drug in water, known as Fluoroformol or Fluoryl. It is odorless and tasteless and is used as an internal antiseptic, alterative, and tuberculocide. It is recommended for consumption and pneumonia. IODOFORM, CHC1 3 Iodoform or tri-iodomethane, famous for its powerful and clinging odor, is formed when ethyl alcohol (not methyl), acetone, aldehyde, and other simple organic substances containing oxygen united with a CH-C group are wanned with alkali or an alkaline carbonate. 744 ORGANIC SUBSTANCES It is used to a large extent as an antiseptic, and though attempts are often made to disguise its presence, its odor will usually be revealed to the operator before he has proceeded far with his investigations. It crystallizes in yellow six-sided plates, melting 115 to 119°, and at higher temperatures emitting vapors of iodin, sublimable with ease and volatile at the ordinary temperature, and with steam. It is very slightly soluble in water and petroleum ether, fairly soluble in alcohol, and readily in chloroform, ether, fixed and volatile oils. When boiled with alcoholic potash it is converted to potassium iodide and formate. Iodoform gives the carbjdamine reaction when heated with aniline and alcoholic potash. When dissolved in chloroform and a crystal of lead nitrate added, a fight rose color appears turning to deep rose and red. Bromoform gives on warming a wine red color passing gradually to garnet- red and finally to reddish-brown. Iodoform unites with many organic bases and sulphocompounds, form- ing definite crystalline compounds, many of which possess antiseptic or other therapeutic properties, but have not the characteristic penetrating odor of iodoform. Estimation of Iodoform. — The determination of iodoform is readily accomplished by boiling for an hour with alcoholic potash under a reflux, evaporating the bulk of the alcohol, diluting with water, acidifying with dilute nitric acid, precipitating with silver nitrate, and filtering the silver iodide onto a Gooch. When working with gauzes or bandages, the sample is introduced into a capacious Erlenmeyer, covered with alcoholic potash and boiled for an hour under a reflux. The liquid is then decanted, and the textile washed with hot alcohol, which is added to the alkaline liquid, and then evaporated, the residue taken up with water, acidified with dilute nitric acid, filtered if necessary, and the iodin precipitated with silver nitrate. Ointments containing iodoform can be similarly treated, but it will be necessary, after acidifying, to shake out any oil or separated acid with ether. The clear aqueous liquid is then drawn off, the ether expelled by gentle heat, and the iodin precipitated with silver nitrate. Iodoform will sometimes be found in pills, either alone or with iron and quinin; also in globules with cod-liver oil; and in oily inhalants with creosote, eucalyptus, etc. In order to present iodoform in a condition where it will be less objec- tionable, various products have been proposed. Aromatized or deodor- ized iodoform is a National Formulary product, prepared by mixing iodoform with 4 per cent of coumarin. Iodoformin is a product obtained by treating iodoform with hexa- methylenetetramine and contains 75 per cent of iodoform. Iodoformogen or Diodoform albuminate is a yellow, fine dry powder, ETHEREAL SALTS— PHENOLS 745 about three times as voluminous as the same weight of iodoform and nearly odorless. The iodoform is liberated on contact with the wounded surface. Ethylene Tetraiodide. Diiodoform, C2I4 Diiodoform crystallizes in yellow needles, odorless when pure, but gradually decomposing on exposure to the light, with the development of a characteristic odor. It melts 187° C, is readily soluble in chloro- form and benzol, slightly in alcohol and ether, and insoluble in water. It is sometimes used instead of iodoform. Iothion, CH 2 ICHOHCH 2 I Iothion or diiodohydroxypropane is obtained by heating dichlorhydrin with potassium iodide in the presence of water. It is a yellowish, oily, heavy liquid, of sp. gr. 2.4 to 2.5, containing 77 per cent of iodin. It is volatile at the body temperature and not unpleasantly odorous. It is insoluble in water but soluble in glycerin, oils, alcohol, and other organic solvents. It is incompatible even with weak alkalies. If iothion is heated on the water-bath under a reflux condenser for five to six hours, with 33 per cent solution of potassium hydroxide and the iodin liberated from the residue by sulphuric acid and sodium nitrate and extracted with carbon disulphide, the titration of this iodine carbon disulphide solution with sodium thiosulphate in the usual way should indicate 77 per cent of iodin. Iodanisol, C^OCHsI • (1 • 2) Iodanisol, or anisol orthoiodide, is a heavy yellow liquid, sp. gr. 1.8 at 20°, boiling 240° C, insoluble in water, but soluble in alcohol, ether, and chloroform. It is an antiseptic and is sometimes used as a substi- tute for iodoform, and is also a local irritant. MERCAPTANS AND THEIR DERIVATIVES Alcohols form two classes of compounds with hydrogen sulphide, the hydrosulphides RSH and the sulphides R2S. The former are called mercaptans on account of their combining readily with mercuric oxide, forming crystalline compounds. The hydrosulphides or sulphhydrates, as they are sometimes called, may be regarded as sulphur- or thioalcohols, and the organic sulphides as thio-ethers. 746 ORGANIC SUBSTANCES Ethyl Mercaptan, C 2 H 5 SH Ethyl mercaptan may be obtained by treating alcohol with phos- phorus pentasulphide, and by distilling a concentrated solution of ethyl potassium sulphate with potassium hydrosulphide. 5C2H5OH+P2S5 = 5C2H5SH+P2O5 C 2 H 5 KS0 4 +KSH = C2H5SH+K2SO4 It is a colorless, unpleasant, garlic-smelling liquid, boiling 36°, it burns with a blue flame, is sparingly soluble in water but dissolves readily in alcohol and ether. It is very volatile and a drop exposed to the air soon solidifies on account of the lowering of the temperature due to the evapor- ation. It is unaffected by caustic alkalies, but sodium or potassium displace hydrogen, fomiing the mercaptides C2H5SM, which are crystalline bodies soluble in water. Mercuric oxide reacts with mercaptan, evolving much heat and form- ing a white crystalline inodorous compound, (C^HsS^Hg, which is insoluble in water, but may be crystallized from alcohol or strong hydrochloric acid. It is unaffected by potash. On oxidation with nitric acid mercaptan is converted into an ethyl sulphuric acid, C2H5SO2OH. The sulphonic acids formed on oxidation of the mercaptan are relatively strong, and their salts differ from the sulphide in not being hydrolyzed when boiled with dilute aqueous potash. Ethyl mercaptan is not a medicinal agent, but it forms the starting- point of a number of important hypnotic drug products, including sul- phonal, trional, and tetronal. These bodies are all obtained by subjecting ethyl mercaptan and an appropriate ketone to the action of dry hydrogen chloride, when condensation takes place and a mercaptol results. On oxidizing the latter with permanganate the hypnotic is obtained. Acetone gives sulphonal, methyl ethyl ketone gives trional, diethyl ketone gives tetronal. Sulphonal, (CHs^CiSC^CoHs^, Diethylsulphonedimethylmethane Sulphonal forms colorless, odorless, tasteless, prismatic crystals, melt- ing 125.5°, slightly soluble in cold water, but dissolving without difficulty in boiling water, alcohol, ether, chloroform, and benzol. When heated with charcoal, mercaptan is evolved, recognized by its garlicky odor, and when heated with sodium acetate, hydrogen sulphide is evolved. ETHEREAL SALTS— PHENOLS 747 Trional, (CHsXCsKoKCSOaCaH^, Diethylsulphonemethylethylmethane Trional forms colorless, lustrous, odorless, crystalline scales, melting 74 to 76° C, fairly soluble in cold water, more readily in boiling water, alcohol, and ether. When heated with charcoal or sodium acetate it gives the same characteristic tests as sulphonal. Tetronal, (C2H 5 )2C(S02C2H 5 )2, Diethylsulpkonediethylmethane Tetronal forms colorless lustrous laminae, with camphoraceous odor and bitter taste, melting 85°, slightly soluble in water, soluble in alcohol and ether. These three bodies are used as hypnotics and sedatives and usually by themselves in the form of pills, tablets, capsules, or powders. They do not give any well-defined color or precipitation tests, but in the general scheme of qualitative analysis they will appear on shaking out an acid aqueous solution with petroleum ether and ether. In the absence of tests indicating other ingredients, portions of the residue should be tested by ignition first with charcoal and then with anhydrous sodium acetate, and if the mercaptan odor is developed in the former and hydrogen sul- phide in the latter, a melting-point determination should be run on the recrystallized substance, and the identity of the individual can then be established. ESTERS OF AROMATIC ALCOHOL The esters of the aromatic alcohols have practically no use in medicine. Benzyl chloride, iodide, sulphide, and benzyl dichloride are all well characterized individuals. The cinnamyl and benzyl esters of cinnamic and benzoic acids are of importance in this work, as they occur in the aromatic balsams and the chemistry of the latter is in large part concerned with the properties of the esters. Thiophene CH=CH I! CH=CH > Thiophene, one of the constituents of coal tar, occurs as an impurity in benzol, and may be separated therefrom by shaking with concentrated sulphuric acid. If the acid contains a trace of isatin (an oxidation product of indigo) a blue color develops which is known as the indophenin reaction. Thiophene is sometimes used as an antiseptic. 748 ORGANIC SUBSTANCES Thiophene Diiodide, C 4 H 2 I 2 S Thiophene diiodide or biniodide in a yellow crystalline substance melt- ing about 40° C, soluble in alcohol, ether, and chloroform, and used as an antiseptic. Thiophene Tetrabromine, C^^S This derivative of thiophene is a yellow powder, melting at 112° C, and used as an antiseptic. THE GLYCEROPHOSPHATES Glycerophosphoric acid, as prepared commercially, is a partially esterified glycerin compound with phosphoric acid. It is probable that only one hydroxyl takes part in the reaction and that two replacable hydrogens of the phosphoric acid remain free. CH 2 OH CHOH CH OH H OH OP OH The salts of glycerophosphoric acid were introduced as nerve foods and tonics and have become very popular. The most important salts found on the market are those of calcium, sodium, and potassium. To a lesser extent we meet with those of iron, manganese, quinin, and strychnin. The glycerophosphates are usually dispensed in the form of elixirs, though sometimes they are given in capsules and of late the manufacture of albumin compounds soluble in water is claimed by processess which consist in mixing albuminoids (milk casein or vegetable casein) suspended in dilute alcohol with the requisite quantity of a glycerophosphate, expelling the alcohol by heat and drying; or in mixing the albuminoid with a dilute solution of the glycerophosphate, filtering, evaporating to dryness, or precipitating with alcohol. Such products are probably more of the nature of mixtures than chemical individuals. Power, Tutin, and Hann, 1 as the result of an interesting research on the glycerophosphoric acids, conclude that the only known products of the reaction between glycerin and phosphoric acid are the monoester (glycerylphosphoric acid), C3Hs(OH)2 • O • PO(OH)2 ; the diester, /\ C 3 H 5 (OH)< >PO.OH; x o/ 1 Trans. Chem. Soc, 1905, 249 and 1906, 1749. ETHEREAL SALTS— PHENOLS 749 and the triester (glycerophosphate), C3H5PO4. The first form can have the unsymmetrical structure CH 2 -OP0 3 H 2 CH2OH CH-OH a-acid or the symmetrical CHOPO3H2 /3-acid CH2OH CH2OH Their investigations indicate that the synthetic product is a mixture of the a- and /3-acids, and that this differs from the acid obtained from lecithin only by a difference in proportion of the components. Glycerophosphoric acid behaves toward methyl orange as a mono- basic acid and toward phenolphthalein as a dibasic acid, similarly to phosphoric acid. Falieres l has worked out a titration method for estimating glycero- phosphates which is applicable to the calcium salt: The determination is carried out by dissolving .2 gram of the salt in a little water, adding 20 mils of decinormal oxalic acid, and making up to 100 mils. Fifty mils of the filtrate, containing the free glycerophosphoric acid, and an excess of oxalic acid, are titrated with decinormal potash and phenol- phthalein and twice the number of mils required =A. The calcium oxalate remaining on the filter, after well washing with boiling water, is dissolved in dilute nitric acid (1 : 10), a few drops of sulphuric acid are added, and the solution is titrated with decinormal permanganate = B. The quantity of lime is expressed by B X .0028, and for 100 grams of glycero- phosphate = BX. 0028X5X100. The formula A+B -20 gives in mils of decinormal potash, the weight of the glycerophosphoric acid contained in .2 gram of the substance, while (A+B -20) X. 0086X5X100 gives the percentage amount of glycerophosphoric acid in the calcium glycero- phosphate. The neutral organic glycerophosphates and the double salts are all amorphous. In the dry state they are stable, but when heated with water they decompose. Quinin glycerophosphate on heating in aqueous solu- tion, gives on cooling a white precipitate of quinin phosphate. For some time the sodium and potassium glycerophosphates were known only in a concentrated solution having the consistency of honey, but a highly purified dry sodium salt has recently been put upon the market. The laboratory of the American Medical Association has made a thorough study of some of the glycerophosphates, and their results quoted below give a very accurate description of the properties of the calcium and sodium salts. ^epert. Pharai., 1898, 10, 8. 750 ORGANIC SUBSTANCES Calcium Glycerophosphate Calcium glycerophosphate is monohydrated calcium glycerophosphate, Ca(CsH5 (OH)2) PO4, H2O, the normal calcium salt of glycerophosphoric acid, H 2 (C3H 5 (OH) 2 )P04, containing not less than 90 per cent of anhy- drous normal calcium glycerophosphate. Calcium glycerophosphate is a fine white powder, odorless and almost tasteless; somewhat hygroscopic. It is slightly (about 1 : 400) soluble in water; almost insoluble in boiling water; easily soluble in dilute acids; insoluble in alcohol or in ether. The aqueous solution is alkaline to red litmus paper. A cold, satu- rated, aqueous solution yields white, iridescent scales when heated to boiling (anhydrous calcium glycerophosphate). At about 130° C. calcium glycerophosphate loses its water of hydra- tion. When heated above 170° C. the salt is decomposed with evolu- tion of inflammable vapors, and at a red heat it is converted into calcium pyrophosphate. On the addition of ammonium oxalate solution, the aqueous solution yields a white precipitate, insoluble in acetic acid or in a solution of citric acid, but soluble in hydrochloric acid. With lead acetate solution the aqueous solution yields a white precipitate which is soluble in nitric acid. If 1 gram of calcium glycerophosphate is dissolved in 10 mils of diluted nitric acid and an equal volume of ammonium molybdate test solution be added, no precipitate should be formed within one hour. If 1 gram of calcium glycerophosphate is dissolved in 100 mils of 1 per cent hydrochloric acid, the solution should not respond to the U. S. P. time-limit test for heavy metals. If .1 gram of calcium glycerophosphate is dissolved in 10 mils of diluted nitric acid and 1 mil of silver nitrate solution added, not more than a distinct opalescence should appear within one minute. If .1 gram of calcium glycerophosphate is dissolved in 10 mils of diluted hydrochloric acid and 1 mil of barium chloride solution added, no distinct turbidity should appear within one minute. If 1 gram of calcium glycerophosphate in water is titrated with N/10 potassium hydroxide, using phenolphthalein as indicator, not more than 1.5 mils of the alkali should be required. If 1 gram of the finely powdered salt is shaken with 25 mils of alcohol, the mixture filtered, the filtrate evaporated on the water-bath and the residue dried for one hour at a temperature not exceeding 70° C. the residue should weigh not more than .01 gram. If from .5 to 1 gram of the finely powdered salt is dried to constant weight at 130° C, the loss should not exceed 10 per cent. ETHEREAL SALTS— PHENOLS 751 If from .3 to .5 gram of anhydrous calcium* glycerophosphate is weighed into a Kjeidahl flask, 10 mils of a mixture of equal parts of fuming nitric acid and concentrated sulphuric acid added, the mixture heated until oxidation is complete, a little more fuming nitric acid being added if necessary, the solution diluted with 50 mils of water and the phosphorus determined in the usual way, by precipitation with ammonium molybdate and final weighing as magnesium pyrophosphate, the weight should cor- respond to from 14.16 to 14.75 per cent of phosphorus. If from .3 to .5 gram of anhydrous calcium glycerophosphate is dis- solved in 20 mils of a 5 per cent solution of citric acid, 80 mils of water added, the calcium precipitated as oxalate in the usual way and weighed as calcium oxide, the calcium oxide should correspond to from 18.7 to 19.8 per cent of calcium. Sodium Glycerophosphate Sodium glycerophosphate is hydrated sodium glycerophosphate, Na 2 (C 3 H5(OH)2)P04 • 5|H 2 0. At about 60° C. it begins to lose its water of hydration; when strongly heated the salt yields inflammable vapors and at a red heat is converted into sodium pyrophosphate. The aqueous solution (1 in 20) is alkaline to litmus and to phenol- phthalein. If an aqueous solution (1 in 20) is acidified with nitric acid, and an equal volume of cold ammonium molybdate solution added, it should remain clear for one hour. On heating, however, a yellow precipitate will be formed. The aqueous solution (1 in 100) acidified with hydrochloric acid, should not respond to the U. S. P. VIII time limit test for heavy metals. The aqueous solution (1 in 100) acidified with hydrochloric acid on addition of barium chloride solution should show no distinct turbidity within one minute. The aqueous solution (1 in 100) acidified with nitric acid should not show more than a slight opalescence with silver nitrate solution. The aqueous solution (1 in 100) acidified with acetic acid should not become turbid within one minute on addition of ammonium oxalate test solution. If 1 gram of sodium glycerophosphate is thoroughly triturated in a mortar with 20 mils of alcohol, the liquid filtered and the alcoholic solu- tion evaporated spontaneously the residue, after drying over sulphuric acid, should correspond to not more than 1 per cent of the weight of the salt taken. If 2 to 3 grams of the salt is weighed, dissolved in distilled water and 752 ORGANIC SUBSTANCES the solution titrated with half-normal hydrochloric acid, using methyl orange as indicator, the acid consumed should correspond to not less than 99 per cent of hydrated sodium glycerophosphate. The pure glycerophosphates in aqueous solution are not precipitated by heat, but are thrown out by alcohol and ether. They give no immedi- ate precipitate with ammonium phosphomolybdate, magnesium mixture, nor uranium acetate. The white silver nitrate precipitate is soluble in excess of water. The white precipitate given by lead acetate is soluble in acetic acid. The presence of glycerophosphates in admixtures is usually indicated by the non-appearance of a precipitate with ammonium molybdate in the cold after considerable time, and a heavy precipitate with the same reagent after another portion has been boiled with nitric or hydrochloric acid. This test, however, is open to objection if one is working with solutions containing a considerable amount of sugar. It is best to make a preliminary test with magnesium mixture which will throw out phos- phates readily even in presence of sugar or oxalic acid. If no precipi- tate is obtained, and on subsequent boiling with nitric acid, neutraliz- ing and adding magnesium mixture, a white precipitate comes out which is soluble in dilute nitric acid and gives a yellow precipitate with ammonium molybdate, the presence of glycerophosphates is established. The glycerophosphates resemble the hypophosphites when subjected to a high temperature in an ignition tube, for they evolve inflammable vapors. They differ from them, however, in their reaction with silver nitrate, for while the hypophosphites give a permanent precipitate which soon turns black, the glycerophosphate compound is soluble in water. If it is desired to determine quantitatively the amount of glycerophos- phates in a mixture, the solution should first be neutralized with ammonia and an excess of magnesia mixture added to precipitate any free phosphate. After filtering and washing, the solution is acidulated with nitric acid and boiled under a reflux for an hour or two. The solution is filtered if neces- sary, treated with excess of ammonia, and precipitated with magnesia mixture. The precipitate is filtered and washed, dissolved in dilute nitric acid, precipitated with ammonium molybdate at 60 to 80° C, the pre- cipitate washed with hot water, dissolved in ammonia water, the solution precipitated with magnesia mixture and allowed to stand overnight. The ammonium magnesium phosphate is then filtered, washed with dilute ammonia, ignited, and weighed as magnesium pyrophosphate. By cal- culating back the amount of glycerophosphoric acid or its salt may be obtained. ETHEREAL SALTS— PHENOLS 753 PHENOLS Phenols are hydroxy-compounds of the aromatic series in which the hydroxy 1 group is attached to the nucleus. They are classed as mono-, di-, trihydric, etc., according to the number of hydroxyls present. Car- bolic acid and the three isomeric cresols or hydroxytoluenes are mono- hydric, resorcinol and its isomers are dihydric, and phoroglucinol is a tri- hydric phenol. Most phenols are colorless crystalline substances, some possessing a characteristic odor, readily soluble in alcohol and ether and to some extent in water, the solubility increasing with the number of hydroxy 1 groups. The monohydric members volatilize readily, while the trihydric phenols usually are decomposed on heating, and distill only moderately with steam. Phenols yield a violet, blue, or green color with ferric chloride, the particular color depending in the case of the di- and trihydric compounds on the relative positions of the hydroxy groups. Ortho dihydric phenols give a green color, becoming violet and then red on adding sodium bicar- bonate, meta compounds a deep violet, and the para a green, immediately changing to yellow due to the formation of quinone. When the phenols are dissolved in concentrated sulphuric acid and treated with a nitroso compound or a nitrite, colored solutions result which after diluting and adding excess of alkali become blue or green. This is known as Liebermann's reaction. The phenolic hydroxyl has certain acid properties, reacting with caus- tic alkalies to fonn salts stable in the presence of water, but decomposed by carbon dioxide and all other acids with regeneration of the phenols. Phenols can thus be removed from ethereal solution by caustic alkalies, and recovered by acidulating and shaking out with ether. They are not removed by carbonates or bicarbonates, and hence are readily separated from acids. The metallic phenolates react with alkyl halides and acid chlorides to form substances analogous to the ethers and ethereal salts, the former being stable to alkalies, the latter undergoing hydrolysis. With phosphorus halides, acetic anhydride and acetyl chloride, the phenols behave in the same way as the alcohols. On oxidation, however, they do not yield aldehydes or ketones. Many of the phenols are of medicinal importance, others are of interest chiefly as they serve to identify certain drugs or essential oils, and still others important in being hydrolytic products of the decomposition of glucosides, and hence aid in the identification of the parent substance. 754 ORGANIC SUBSTANCES Phenol or Carbolic Acid, C 6 H 5 OH Carbolic acid, or hydroxybenzene, is a powerful antiseptic and will often be found as one of the ingredients of a medicinal product. It is dispensed with petrolatum, and occurs in ointments combined with zinc oxide, menthol, turpentine, tannin, glycerin, and other antiseptic and astringent drugs. Some of the most widely advertised ointments and medicated soaps contain as the sole ingredient on which any claim of virtue can be claimed, a minute quantity of phenol or cresol. Solutions of carbolic acid are used for aborting boils, carbuncles, and coldsores; for urethral injections and for spraying the throat and nose. It is also dispensed with iodin in admixture with glycerin and with sodium sulphoricinate. The carbolates or phenates of sodium and potassium are antiseptics, soluble in water, and used internally in diarrhea, dysentery, and t}"phoid fever. Zinc phenate is only slightly soluble in water and is used as a dusting powder in surgeiy and skin diseases. Bismuth phenate is used as an intestinal antiseptic and for external purpose as an iodoform sub- stitute. The phenates of quinin and cocain are of commercial importance, the latter especially being employed in catarrhal conditions, alone and with acetanilid and menthol. A mixture of equal parts of camphor and car- bolic acid is used in dyspepsia, flatulency, toothache, etc. Pure carbolic acid forms beautiful snow-white crystals having a characteristic odor and a caustic action on the skin and flesh. When moist it forms a syrupy liquid, and as usually obtained in -analytical work it remains in the liquid form. The crystals have a peculiar property of gradually turning red, the color appearing in that portion of the mass which is furthest from exposure to the air and extending to the surface. The crystals melt at 40° C. and the liquid boils at 17&-182° C. It is volatile at all temperatures. It is readily soluble in alcohol, ether, chloro- form, glycerin, olive oil, and other organic liquids, and dissolves quite easily in water. It is practically insoluble in petroleum ether, but the absolute acid is miscible, being thrown out if a trace of moisture is present. It may be removed from acid solution with ether, and can be shaken out of ether or other organic solvents by sodium hydroxide, but not by car- bonates. The alkaline phenolate solutions are decomposed by mineral acids. On account of the difference in the behavior of phenols and carboxy acids toward mild alkalies it is a simple matter to separate them by first dissolving in ether and chloroform, shaking out the acids with bicarbonate solution, and then removing the phenols by sodium hydroxide. An aqueous solution of carbolic acid gives with bromin water a white precipitate which at first redissolves and then becomes permanent as more ETHEREAL SALTS— PHENOLS 755 of the reagent is added. It appears to be orange yellow when viewed in solution. This precipitate has the composition of tribromphenol bromide. On filtering and washing with dilute sulphite and then with water, tri- bromphenol is left, which has the composition C 6 H 2 Br 3 OH, and which on drying over sulphuric acid melts 95° C. When a dilute aqueous solution of carbolic acid is treated with a drop of dilute ferric chloride a violet blue color is ob tamed. If an aqueous solution is mixed with a little dilute ammonia water and treated with sodium hypochlorite solution a blue color develops. Albumen and collodion solutions are coagulated by carbolic acid. Ortho and para nitrophenols are obtained by treating phenol with dilute nitric acid in the cold. The former can be separated from the latter by steam distillation. The meta compound is obtainable only indirectly. They melt respectively 45°, 96°, 114°. Trinitrophenol or picric acid is obtained when phenol is dissolved in concentrated sulphuric acid and concentrated nitric acid gradually added. It forms brilliant yellow crystals melting 122.5° C. and is of medicinal importance. When carbolic acid is fused with phthalic anhydride it gives phenol- phthalein, w T hich is recognized by the intense beet-red color imparted to an alkaline solution. The procedure which is also applicable to all phenols is as follows: Equal weights of the sample and reagent, amounting to .05 gram, are introduced into a dry test-tube, moistened with a drop of concentrated sulphuric acid and heated in an oil-bath at 160° for three minutes. The mixture is then cooled, 2 mils of water added and 1 to 2 mils of dilute sodium hydroxide. Resorcin gives fluorescein, guaiacol gives a violet blue to violet color, orcin orange red. When carbolic acid is dissolved in chloroform, a small piece of potas- sium hydroxide added and boiled, the liquid gradually assumes a pink color. Other phenols give more or less characteristic colors. In the general scheme of qualitative analysis carbolic acid will appear as an oily residue on evaporating the ether shake-out from acid solution. If it is present in marked quantity its odor will distinguish it, and its presence can then be further substantiated by dissolving a small quantity in water and testing the solution with ferric chloride. The tribrom deriv- ative should then be prepared and its melting-point determined and the phthalein fusion performed. If the presence of carboxy acids is suspected the residue should be dis- solved in ether and shaken with sodium bicarbonate solution in order to remove them. The phenol can then be shaken out with sodium hydroxide and recovered by adding excess of mineral acid and shaking out with ether. When carbolic acid occurs in ointments or in oily mixtures, it can be 756 ORGANIC SUBSTANCES determined by dissolving a weighed portion in ether and extracting the solution three times with dilute sodium hydroxide. The alkaline solution is acidulated with hydrochloric acid and if a precipitate occurs due to fatty acids, the liquid is cooled, filtered, the filter washed with water, the acid liquid treated with an excess of bromin water, stoppered, and allowed to stand until the precipitate has agglomerated, when it is filtered onto a tared Gooch, washed with sulphite solution, and then several times with cold water. It is then dried over sulphuric acid and weighed. Soaps should be dissolved in warm water and the solution precipitated with hydrochloric acid. When the fatty acids have separated, the mix- ture is poured onto a wet filter paper and the precipitate washed several times with water. The phenol which now is present in the filtrate and washings is ready for the bromin precipitation. The pharmacopceial method for the evaluation of this substance is as follows: Dissolve about 1.5 grams of the Phenol to be assayed, accurately weighed, in sufficient distilled water to make 1000 mils. Transfer an aliquot portion of this solution, containing not less than .038 gram not more than .041 gram of Phenol, to a 500-mil glass-stoppered flask having a long, narrow neck, add 30 mils of N/10 bromine V. S., then 5 mils of hydrochloric acid, and immediately insert the stopper. Shake the flask repeatedly during half an hour, allow it to stand for fifteen minutes, remove the stopper just sufficiently to introduce quickly 5 mils of an aqueous solution of potassium iodide (1 in 5), being careful that no bromin vapor escapes, and at once stopper the flask. Shake the latter thoroughly, remove the stopper and rinse it and the neck of the flask with a little dis- tilled water, so that the washings may flow into the flask, then add 1 mil of chloroform, shake the mixture well and titrate with N/10 sodium thio- sulphate V. S., using starch T. S. as indicator. It shows not less than 97 per cent of C 6 H 5 OH. Each mil of N/10 bromin V. S. corresponds to .001568 gram of C6H5OH. Each gram of Phenol corresponds to not less than 618.6 mils of N/10 bromin V. S. Trinitrophenol or Picric Acid, C 6 H 2 (N0 2 )30H This substance is almost universally known as picric acid, and is remark- able for its brilliant yellow color, which persists even in very dilute solu- tions. It melts 122.5°, soluble in alcohol, ether, chloroform, and to a moderate extent in water. It has strong acid properties, decomposing carbonates and forming explosive salts. The potassium salt is sparingly soluble in water, but the sodium compound dissolves with ease. Picric acid gives precipitates with many of the alkaloids and an especi- ETHEREAL SALTS— PHENOLS 757 ally insoluble compound with antipyrin. It coagulates albumen and gelatin, and forms crystalline compounds with benzol, naphthalene, anthracene and many other hydrocarbons, so that it is sometimes used in detecting and purifying small quantities of these substances. It is removed from its solution in mineral acids by immiscible solvents, and may be identified by the above-mentioned properties and by its dyeing of silk and wool, but not cotton. It can be titrated with alkali, using phenolphthalein as an indicator. Picric acid is an antiseptic. The acid and its salts are used in malaria and trichimasis ; externally for burns, hemorrhage, erysipelas, eczema, etc., and as an injection for gonorrhea. Picric acid gauze is an important agent in surgical practice. The silver compound is called Picratol, and is used as an antiseptic in gonorrhea and in catarrhal affections of the throat and nose. Tribromphenol, C 6 H 2 Br s OH Tribromphenol or Bromal is a white to reddish crystalline powder with a bromin-like odor. It melts 95°, is insoluble in water, but dis- solves in the ordinary organic solvents. It is employed as an external and internal antiseptic. It is given in cases of typhoid fever, cholera infantum, etc., and externally is applied to wounds and running sores, and in the form of glycerin solution in diph- theria. It is often dispensed in an oily medicine or in the form of an ointment. A product of somewhat uncertain composition, but claiming to be a bismuth tribromphenate is known as Xeroform. It contains 57 to 61 per cent Bi2C>3, and is a yellow, neutral, insoluble powder possessing the combined virtues of bismuth and tribromphenol. According to the patent it is obtained by dissolving tribromphenol in sodium hydroxide and adding bismuth nitrate to the sodium tribrom- phenolate solution. The precipitated tribromphenol bismuth is collected and washed with alcohol. It is insoluble in water, alcohol, chloroform, liquid petrolatum, and vegetable oils, but soluble in 2 per cent hydrochloric acid in the propor- tion of 30 : 100. By alkalies it is decomposed with the formation of bromides; it is not decomposed by heat at temperatures below 120° C. It should yield 59.5 per cent of bismuth oxide. If 1 gram is boiled with sodium hydroxide T. S. filtered, the filtrate rendered acid with sul- phuric acid and the white, curdy precipitate washed and dried, it should melt at 95° C. It is useful as an odorless and efficient substitute for iodoform in weeping eczemas; internally, in gastrointestinal catarrh, proctitis, dysen- tery, bacillary and choleraic diarrhea, cholera infantum, etc. 758 ORGANIC SUBSTANCES Paraiodophenol, C 6 H 4 OHI Phenol iodide is a colorless or reddish crystalline substance melting about 92°, used as an antiseptic by itself or in glycerin admixture and is applied in diphtheria, cancer, leucorrhea, ringworm, and other diseases where a strong antiseptic is indicated. Ethyl Carbolate, C c H 5 OC2H 5 The ethyl ester of phenol known as Phenetol is an oily liquid, boiling 172°, soluble in alcohol and ether. The Cresols, C 6 H 4 OH • CH 3 The three isomeric cresols occur in coal tar and a purified mixture of the three compose the pharmacopceial product known as cresol or cresylic acid. It is used as a disinfectant and antiseptic either by itself or in admix- ture with soap. Large quantities of crude cresol are used in the manu- facture of sheep and cattle dips. Household antiseptics of the creolin and lysol type contain essential quantities of neutralized cresols. The cresols resemble carbolic acid in most of their properties; they form sodium and potassium cresylates, which are decomposed by carbon dioxide and by stronger mineral acids, so that on acidifying an alkaline solution they may be shaken out with ether. They yield alkyi derivatives by the displacement of the hydrogen in the hydroxyl group, and on dis- tillation with zinc dust they are all converted into toluene. They give blue colors with ferric chloride. Ortho cresol melts 31°, boils 188°; meta melts 5°, boils 201°; para melts 36°, boils 198°. The presence of the hydroxyl group in the cresols protects the methyl group from the easy oxidation which characterizes the methyl group of toluene. However, if the hydrogen of the hydroxyl is replaced by a radicle, the protective influence is removed and substances like methyl cresol, C6H4CH3 • OCH3, are readily oxidized to benzoic acid derivatives. The cresols are soluble in water to some extent, and mix in all propor- tions with alcohol, ether, and petroleum ether, differing in this last respect from carbolic acid. Estimation of Cresols or Cresylic Acid in Cattle Dips. — Chapin. — Fifty grams of coal-tar cresote or 15 to 20 grams of cresylic acid dip are weighed into a 500-mil round-bottomed flask, 20 mils of 1 : 3 H2SO4 are added, and the phenols are distilled off with steam. The flask will require no heating if a rapid current of steam is passed into it, but may with advan- tage be packed in cotton or felt. Obviously the apparatus must be so set up and the distillation so conducted that particles of resin may not be ' ETHEREAL SALTS— PHENOLS 759 mechanically carried over by the current of steam. Toward the end of the distillation any naphthalene in the condenser is melted out by shutting off the water for a few minutes, or if separated earlier in sufficient quantity to threaten stoppage of the condenser tube, distillation is interrupted while hot water is run through the condenser. The distillate is received in a liter flask approximately marked for each 100-mils capacity and joined to the condenser by a cork, which is pierced by a small glass tube connected to a small U-tube containing a little dilute caustic soda. The latter acts as a trap to prevent any loss of the distilled phenols. Distillation is continued untill 1 or 2 mils collected in a test tube gives no reaction with any appropriate reagent for phenols, such as ferric chloride. A volume of 800 mils is ample in nearly all cases. A supply of benzol should be prepared by shaking a good grade of benzol with dilute sulphuric acid, then with dilute caustic soda two or three times, and then passing through a dry filter. A small wash bottle containing some of this benzol will be found very useful for rinsing the necks of separatory funnels, etc. Of this purified benzol 150 mils are measured out conveniently at hand, the contents of the U-tube and 5 mils of 1 : 1 H2SO4 are added to the distillate, and the latter is shaken up and poured into a separatory funnel of 1500 mils capacity, the flask being rinsed out with successive portions of the 150 mils benzol. When all is in the funnel 25 grams of clean sodium chloride is added for each 100 mils of distillate, and the funnel well shaken for five minutes and left at rest one-half hour. The aqueous layer is then run off slowly and com- pletely, the funnel being allowed to stand until there is no further separa- tion. The benzol solution of phenols and hydrocarbons is transferred to a 500-mil Erlenmeyer flask, while the aqueous portion is poured back into the separating funnel and extracted twice more in the same way, 100 mils of benzol being used each time. The funnel should always be gently handled after the aqueous portion has been drawn off, to prevent any impurities from the sodium chloride which have deposited upon its sides from becoming mixed with the benzol solution. The three benzol extracts are united in the Erlenmeyer flask, 15 mils of pure caustic soda solution, 1 : 2, is added, and the contents of the flask are subjected to a rotatory motion for some time in order that the phenols may be taken up by the caustic soda as completely as possible. After the addition of a few grains of sand the flask is immersed in a water-bath, connected to a condenser, and all but 40 to 50 mils of the benzol distilled off. With the aid of a wash-bottle containing water and provided with a fine jet, only a small portion of water being used at a time, the contents of the flask are next carefully washed into a 150-mil separatory funnel. With proper manipulation the flask should be com* pletely washed when the volume of aqueous portion in the separatory 760 ORGANIC SUBSTANCES tunnel amounts to not more than 50 mils. Ten mils of strong sulphuric acid (100 mils pure concentrated H2SO4 to 120 mils water) is next slowly introduced with gentle rotation of the funnel, the addition of acid being interrupted and the funnel cooled whenever it becomes unpleasantly warm to the hand. Two or three drops of methyl orange are now added; and if on mixing the contents of the funnel the lower layer does not acquire a pink color. tLe addition of acid is continued until acidity is assured. Sufficient benzol is then added to make the two layers in the funnel approxi- mately equal in volume, the funnel is thoroughly shaken, and with loosened stopper, left at rest for two hours. After that time the aqueous layer is slowly and completely run out, the analyst making sure that on longer standing no more will drain down from the sides of the funnel. The benzol solution of phenols is then readjr to be transferred to the measuring tube. The measuring tube consists of a glass-stoppered pear-shaped bulb of about 100 mils capacity, joined at its tapering end to a tube about 1 foot long and of a capacity of 25 to 30 mils. This tube is accurately graduated to contain 25 mils at 20° C. in divisions of one-tenth mil. The apparatus is cleaned thoroughly with soap powder and hot water, and dried, best spontaneously, though alcohol and ether may be used if pure. Perfect cleanliness is essential to insure a properly shaped meniscus. Between 15 and 16 mils of caustic soda solution, 1 : 3, is brought into the tube with a pipette. The caustic soda should not be allowed to come in contact with the interior of the bulb or the upper part of the tube. After a few moments about 1 mil of benzol is added, and after waiting a little the height to the top of the now almost flat meniscus is noted. The benzol solution of phenols is next transferred from the separators funnel to the tube, care being used to avoid mixing with the soda; the separatory funnel is washed out with a little benzol, which is also transferred to the tube, and the height of the meniscus is again noted. The latter may often be obtained more accurately at this point. The tube is then stop- pered, vigorously shaken for three minutes, and set aside for at least three hours. An occasional rapid rotation of the tube between the palms of the hands will insure a complete separation of the layers. Each mil increase in volume of the caustic soda solution may be taken to represent one gram of phenols. All readings of the tube should be taken at the top of the meniscus and at a temperature as near 20° C. as practicable. Europhen Di-Isobutyl-Cresol Iodide, C 6 H3(C 4 H 9 )(CH3)(OI)-C 6 H2(CH3)( : 0)(.C 4 H 9 ), is a condensation product of 2 molecules of isobutylorthocresol, with 1 atom of iodin, analogous to thymol iodide. ETHEREAL SALTS— PHENOLS 761 It forms a yellow, voluminous powder, fusing at 110° C, containing 28 per cent of iodin, and having a faint saffron-like odor. It is insoluble in water or glycerin, but readily soluble in alcohol, ether, chloroform, and the fixed oils. It is permanent in the dry state, but splits off iodin readily when moistened and rapidly when heated with water at 70° C, particularly in the presence of alkalies. When triturated with glycerin and water, it yields a filtrate which is turned bluish by the addition of freshly prepared starch paste. Its alco- holic solution produces a yellow precipitate with mercuric chloride. Triiodometacresol or Losophan, C 6 HI 3 OHCH 3 Losophan is a colorless, crystalline body with a strong characteristic odor. It is insoluble in water and only slightly in alcohol, but dissolves in ether and chloroform and is used in alcoholic solution or in ointments for eczema, acute inflammation and parasitic skin diseases. Cinnamylmetacresol or Hetacresol This is a white crystalline powder, insoluble in water, but dissolving in ether, in which solution it is used as an antiseptic wash for sores, fistulas, and tubercular lesions. The Cresalols The cresylic esters of salicylic acid are called cresalols, CeHiOHCOOCeEUCHa. They are all white crystalline powders soluble in alcohol and ether and insoluble in water, the ortho, melting 35°, is not of importance therapeu- tically; the meta, melting 74°, and the para, melting 39°, are used for the same purposes as salol. Cre satin Meta-cresyl acetate is the acetic acid ester, CH 3 C6H4-0(CH 3 CO), of meta-cresol, CHsCeHi-OH. Cresatin occurs as a colorless, oily liquid, possessing a characteristic odor. It is practically insoluble in water, but soluble in the ordinary organic solvents, miscible with liquid petrolatum, fixed and volatile oils and is volatile with steam. It is said to be useful in the treatment of affections of the nose, throat, and ear. 762 ORGANIC SUBSTANCES Thymol, CH 4 (CH 3 )C 3 H 7 Thymol, which is isomeric with carvacrol, is a monohydroxy-derivative of cymene. Constitutionally it is CH3 / \ OH CH(CH 3 ) 2 Thymol has attained considerable reputation as an antiseptic and anthelmintic. It is usually a component of mouth washes and gargles, and will often be found in tooth pastes and powders. It is used internally for rheumatism, gout, typhus fever, whooping cough, influenza, and gastric fermentation and as an expellant of the hook-worm. Its presence may be suspected in remedies intended for any of the above diseases. The various combinations of mouth washes and gargles are too numer- ous to describe, but any of the listerine type or the glycothymoline type will probably contain thymol. One type of " shot gun " formula recom- mended as an astringent and antiseptic for leucorrhea contains thymol, eucalyptol, tannic, salicylic and boric acids, alum, and the extracts of Hyoscyamus, opium, helonias, and witch hazel, sold in tablet form. Nasal tablets contain thymol, menthol, eucalyptol, methyl salicylate, and the bicarbonate, borate, chloride, benzoate, and salicylate of sodium. Thymol occurs in the volatile oil of Thymus vulgaris the common or garden thyme, in the volatile oils of Monarda punctata, Morula japonica, Cunila mariana, and Carum ajowan. Thymol forms colorless transparent crystals, with a characteristic thyme-like, pleasant odor, melting 50-51° and boiling 220-322°. It dis- solves but slightly in water, but is readily soluble in alcohol, ether, chloro- form, petroleum ether, glacial acetic acid and the fixed oils. It forms soluble salts with alkalies. When triturated with camphor, menthol or chloral hydrate, a liquid is produced. It gradually volatilizes at the tem- perature of the water-bath. An aqueous solution of thymol does not give a blue color with ferric chloride, but a concentrated solution in alcohol gives a transient blue color with a trace of the very dilute reagent. If a small crystal is dis- solved in 1 mil of glacial acetic acid and treated with 6 drops of concen- trated sulphuric acid and 1 of nitric acid, a deep bluish-green color will appear. A solution of thymol in sodium hydroxide when agitated with chloro- form develops a violet color. ETHEREAL SALTS— PHENOLS 763 A veiy characteristic test for thymol consists in dissolving a suspected residue in a small quantity of sodium hydroxide solution and adding slight excess of a solution of iodin in potassium iodide, when a brilliant red precipitate of di-thymol diiodide will gradually settle out. This substance is insoluble in water but dissolves in ether. It has the compo- sition C20H24O2I2. If 1 gram of thymol is dissolved in 1 mil of concentrated sulphuric acid, added to a mixture of 1 mil each of nitric acid and sulphuric acid and subjected to the temperature of a boiling water-bath for three to four minutes, trinitro thymol is formed, which may be obtained in a pure condition by pouring the mixture into 20 mils of cold water, cooling, shaking, filtering, washing, and then recrystallizing from a mixture of 10 mils water, 4 mils alcohol and .5 mil concentrated hydrochloric acid. It melts 109 to 110°. When fused with phthalic anhydride the product has a violet-red to red color, which dissolves in sodium hydroxide with an intense blue. When it is desired to determine thymol in admixture with other anti- septic agents such as are usually found in dentifrices, douches, etc., a measured quantity of the sample is introduced into a distilling flask arranged for steam distillation, with an outlet tube in the form of a spray trap such as is used in running Kjeldahl distillations. The material is diluted with water, acidulated with phosphoric acid, and distilled with the aid of a current of steam. The distillate is recovered in a flask closed as tightly as possible and surrounded with cold water. The amount of liquid to be collected depends on the nature of the sample, but it is well to continue the operation for half or three-quarters of an hour. The dis- tillate is tested for acidity and if the reaction is acid a slight excess of sodium bicarbonate* is added. It is then transferred to a separator and shaken out two or three times with ether, the ether extracts united, shaken with dilute caustic alkali, the alkaline solution transferred to a distilling apparatus of the type above described, acidulated with phosphoric acid and the thymol distilled off, collecting the distillate in a glass-stoppered flask. The estimation of the thymol in the distillate then follows the procedure of Seidell. 1 One mil of carbon tetrachloride is added and then bromin vapor poured in, a little at a time with alternate shaking and addition of bromin until the mixture retains a distinct brown color. After allowing to stand in a dark place for one-half hour, 5 mils carbon sulphide followed by 5 mils of 20 per cent potassium iodide solution are added, the bottle well shaken, N/10 thiosulphate run in until the pink color in the carbon bisulphide layer is just discharged, an additional amount of potassium iodide added, when if no further liberation of iodin occurs, the reading of the burette is taken. Five mils of 20 per cent potas- 1 Amer. Chem. Journal, 47, 508. 764 ORGANIC SUBSTANCES sium iodate solution are added, the flask well shaken, and titration with thiosulphate continued until the iodin color is discharged a second time. The completion of the reaction may be tested by a further addition of iodide and iodate solutions. The difference between the first reading and the second corresponds to the hydrobromic acid formed by the action of the bromin on the thymol. The calculation is made on the basis of 2 molecules of hydrobromic acid to one of thymol. One mil N/10 thio- sulphate is therefore equivalent to .0075056 gram of thymol. Assay of Thymol. — The weighed sample of .1 to .5 gram of thymol is placed in a 300-mil stoppered bottle with 1 to 2 mils of carbon tetrachloride and 100 mils of water. Bromin vapor is then poured into the mixture till there is considerable excess after shaking. After half an hour, 5 mils of carbon bisulphide and 5 mils of 20 per cent potassium iodide solution are added, and the free iodin is titrated by means of N/10 thiosulphide solution. After adding a little more iodide, no further liberation of iodin should take place. Five mils of 2 per cent potassium iodate solu- tion are then added, and the free iodin again titrated. The result is calculated as above described. Dithymol diiodide, (QI^CHsOICsHt^ This substance which we will call simply thymol iodide, is extensively used as a substitute for iodoform in antiseptic dusting powders, medicated gauzes, and bandages. It is sold under a number of different names including aristol, thymoto, iodistol, iodohydromol, iodothymol, iodosol, iosol, iothymol, thymiode, thymodin, etc. Thymol iodide is a bright-red or pinkish red powder with a slight odor and a chalky feel. It is insoluble in water and only ^slightly in alcohol, but dissolves readily in ether, chloroform, and oils. On exposure to light it is gradually decomposed. U. S. P. Method of Assay. — Mix thoroughly about .25 gram of Thymol Iodide, previously dried to constant weight in a desiccator over sulphuric acid and accurately weighed, with about 3 grams of anhydrous sodium carbonate. Cover the mixture with about 1 gram more of anhydrous sodium carbonate and heat it moderately, in a crucible, gradually increas- ing the heat, but not exceeding a dull redness, until the mass is completely carbonized. When sufficiently cooled, extract the residue with boiling distilled water and wash it on a filter with boiling distilled water until the washing ceases to produce an opalescence with silver nitrate T. S. Heat the combined washings, which measure about 150 mils on a water- bath and add an aqueous solution of potassium pemanganate (1 in 20) in small portions, until the hot liquid remains permanently pink. Then add just enough alcohol to remove the pink tint, cool the liquid to room ETHEREAL SALTS— PHENOLS 765 temperature, and dilute it to 200 mils. Mix it well and then filter through a dry filter, rejecting the first 50 mils of filtrate. To 100 mils of the sub- sequent clear filtrate add about 1 gram of potassium iodide (free from iodate) and an excess of diluted sulphuric acid, and titrate the liberated iodin with N/10 sodium thiosulphate V. S., adding starch T. S. near the end of the titration. It shows in the dried Thymol Iodide, not less than 43 per cent of I. Each mil of the N/10 sodium thiosulphate V. S. used corresponds to .002115 gram of I. Each gram of Thymol Iodide corresponds to not less than 203.3 mils of N/10 sodium thiosulphate V. S. Thymol Salicylate, C 10 Hi3OC 7 H 5 O3 Thymol salicylate or salithymol is the reaction product of sodium salicylate with sodium thymolate and phosphorus tri-chloride. It is a white crystalline powder, soluble in alcohol and ether and slightly in water, used as an antiseptic. Thymol Carbonate Thymol carbonate, thymotol, or tyratol is a derivative of thymol obtained by passing phosgene gas into a solution of sodium thymolate. It forms colorless crystals with a faint odor of thymol, soluble in alcohol, ether, and chloroform and insoluble in water. It is used as a vermifuge. Thymoform Thymoform is a condensation product of thymol and formaldehyde, soluble in alcohol, ether, chloroform, and oils, insoluble in water, and used as a substitute for iodoform. Carvacrol Carvacrol has the constitution CH3 OH CH(CH 3 ) 2 showing its close relationship to thymol. It is a liquid of specific gravity .981 at 15 °C, melting +.5° C, boiling 236-137° C, its alcoholic solution giving a green color with ferric chloride. In odor and general character- istics it is very similar to thymol. In concentrated solution with alcohol 706 ORGANIC SUBSTANCES it gives a transient dirty-green color with a small quantity of dilute ferric chloride. This phenol often accompanies thymol in oil of thyme from certain sources, in fact sometimes replaces its isomer entirely. Its chief sources, however, are the oils of several species of Origanum. The oil of 0. vul- gare, Wild Marjoram, is used as an antiseptic and emmenagogue, and in the trade the oil commonly called " oil origanum " is really thyme oil. Cretan origanum oil, of which there are two varieties, the Triest and Smyrna oil, has no special interest to the drug chemist. Dihydric Phenols The dihydric phenols and their derivatives furnish a number of interest- ing and important medicinal bodies. . The relationship of the three iso- meric dihydric phenols is apparent from the following f ormulae : OH OH I I l-OH OH Catechol or Ortho-dihydroxy- Resorcinol or Meta-dihydroxy- Hydroquinone or Para-dihydroxy- benzene benzene benzene Catechol, C 6 H 4 (OH) 2 Catechol or pyrocatechin is widely distributed in nature, being associ- ated with the tannins occurring in a great variety of plants, these par- ticular tannins giving a greenish-black or greenish-brown color with ferric chloride. It is present in catechu or cutch, an extract prepared from the wood of Acacia catechu, and is used as an astrigent. Catechol is a colorless crystalline substance, melting 104° C, readily soluble in water, alcohol, and ether. Its aqueous solution gives a green color with ferric chloride, changing to violet and red on the addition of sodium bicarbonate and being restored to green on the cautious addition of sodium hydroxide. It reduces alkaline copper sulphate and silver nitrate in the cold, and gives a precipitate with lead acetate. In presence of alkalies it absorbs oxygen from the air, becoming brown and black; lime water causes a reddish or brown color. Pine wood moistened with hydrochloric acid is colored blue by a solution of catechol. Catechol is an antiseptic and antipyretic and is used externally in solutions and ointments for burns, wounds, etc. ETHEREAL SALTS— PHENOLS 767 Aqueous solutions of catechol are neutral, but on adding borax the liquid acquires acid properties and decomposes carbonates. Pyrogallol and gallates of the alkalies act in the same way, but resorcinol, hydro- quinone, and orcinol do not. When the phthalein fusion test is applied, the melt gives a blue color with alkali. Catechol is used to a limited extent as a remedial agent, but several of its derivatives are of marked importance. The monomethyl ester is well known as guaiacol, the dimethyl ester as veratrole, the monoethyl ester as guaethol, and the methyl benzyl ester as brenzcain. The sodium salt of its acetate, CeELiOH • OCH 2 COOXa, is called guaiacetin, and is used in tuberculosis. The tetrabrom-compound, useful for identification, may be prepared by dissolving .5 gram of catechol in 2.5 mils chloroform and adding .4 mil bromin. The solvent is evaporated, the residue dissolved in 5 mils cold alcohol, 20 mils water added, shaken, filtered, washed with 5 mils water and the procedure repeated. The resulting product after drying on a tile will soften at about 185-187°, melting 192-193°. Guaiacol or Methyl catechol, CeH^OH^CHs Guaiacol is an important constituent of beechwood creosote, and is present in the distillate of other woods as well. Considerable quantities are obtained on distilling the heart wood of Guaiacum officinale, Lignum Vita?. Pure guaiacol is a faintly yellowish, limpid oily liquid with a character- istic aromatic odor. Its specific gravity is 1.110 to 1.220 at 15° G, and it boils 201 to 207° C, readily soluble in alcohol, ether, glycerin, glacial acetic acid, and fairly soluble in water. Its aqueous solution gives an emerald-green color with ferric chloride. It acts as a reducing agent in alkaline solution. Guaiacol when heated with hydriodic acid yields methyl iodide and catechol. It has the properties of a weak acid, and its salts are decomposed by mineral acids. When potassium guaiacol is heated with methyl iodide, it yields methyl guaiacol, C6Hi(OCH3)2, known as veratrol. Veratrol is an aromatic liquid which is also obtained by heating veratric acid with barium oxide. If .1 gram of guaiacol in 1 mil of water is treated with .2 gram of picric acid in 5 mils of hot water, shaken and cooled slowly, orange crys- tals are obtained which when separated and washed will melt at 86° C. The chief use of guaiacol is in remedies for tuberculosis and pneumonia. It has antiseptic and antipyretic properties also, but its use for these purposes is limited. It is dispensed in capsules and pills and mixed with 768 ORGANIC SUBSTANCES wine and other alcoholic solutions. When used locally it is combined with fixed oils and glycerin. It is often combined with hypophosphites in elixirs and tablets, and may be anticipated in any proprietary remedy advertised for tubercular conditions, malt extract, and cod liver compounds especially. Beechwood creosote has perhaps a more general use than pure guaiacol, but as this creosote, when medicinally pure, consists of about 90 per cent of guaiacol, the chemistry of the two may be considered simul- taneously. Beechwood creosote, and for all intents and purposes guaiacol, will be found combined with bismuth subnitrate in tablets, with cerium oxalate, Nux Vomica and pepsin, with extracts of Podophyllum, Leptandra, Euonymus, and chirata as an intestinal tonic; with cod liver or olive oils in tonic capsules, with oil of santal ar.d eucalyptus; and with iodoform, eucalyptol, and other antiseptics in oily inhalants. Guaiacol has been an attractive body for the chemical manufacturer to manipulate and exploit in various combinations. One of these deriva- tives, the carbonate, is official in our Pharmacopoeia. Guaiacol Carbonate OC6H4OCH3 OC6H4OCH3 co/ The name Duotol is also applied to this substance, which is a white crystalline, odorless, tasteless powder obtained by the action of carbonyl chloride on sodium guaiacol. It is insoluble in water, slightly soluble in glycerin and fixed oils, but dissolves readily in alcohol, ether, and chloroform. It melts 84 to 87°. It is saponified by alcoholic potash, and on acidulating the guaiacol is freed and may be recovered by shaking with ether. An alcoholic solution does not give a bluish-green color with ferric chloride. Guaiacol Benzoate ,OCH 3 CeH4< OOCC 6 H 5 Benzoyl guaiacol or Benzosol is prepared by warming the potassium salt of guaiacol with benzoyl chloride and crystallizing the product from hot alcohol. It forms colorless, minute crystals which melt at 59 to 61° C; they are odorless and tasteless or nearly so. It is practically insoluble in water, sparingly soluble in ether, but readily soluble in hot alcohol. It contains 54 per cent of guaiacol. ETHEREAL SALTS— PHENOLS 769 It forms with sulphuric acid a permanent yellow coloration which on the addition of acetone assumes a characteristic, brilliant cherry-red color, distinguishing it from salol, which gives a yellow color. Ferric chloride produces in the benzosol sulphuric acid mixture a violet color, changing to green and blue, and on the further addition of nitric acid, to orange and green, or of potassium nitrate to green, violet, and yellow. When heated with alcoholic potash, the odor of guaiacol is developed. Its uses are analogous to those of creosote and of benzoic acid. It is said to be useful in incipient pulmonary tuberculosis, as an intestinal anti- septic in fermentation, diarrhea, typhoid fever, diabetes mellitus, and as a urinary disinfectant in cystitis, etc. Guaiacolbenzyl-ester or Brenzcain, /OCH3 X)CH 2 C 6 H 5 Brenzcain is used as a local anesthetic. It forms colorless crystals, melting at 62° C, soluble in alcohol, ether, and fixed oils. Its properties in comparison with the other local anesthetics have already been dis- cussed in the chapter on Cocain. Guaiacol Camphorate, CgHi^COOCeKiOCHs^ This body, also called Guacamphol, is employed in certain conditions of phthisis, and is crystalline, insoluble in water, but soluble in alcohol and chloroform. Guaiacol Cinnamate or Styracol Styracol is guaiacyl cinnamate, C6H5CH : CH-CO-0-(C6H4'OCH 3 ), the cinnamic acid ester of guaiacol. It forms colorless, odorless, and tasteless crystalline needles, melting at 130° C. It is insoluble in water, but easily soluble in alcohol, acetone, chloroform, and benzine. It contains 55 per cent of guaiacol, which is split off by the action of alkalies. Styracol is an intestinal antiseptic. It is useful in the initial stage of tuberculosis, in chronic enteritis, and in intestinal disturbances in general, catarrh of the bladder, etc. Guaiacol Glycerylether or Guaiamar Guaiamar is glyceryl guaiacolate, CH3O • C 6 H 4 • 0(CH 2 OH • CHOH • CH 2 ). 770 ORGANIC SUBSTANCES It is a white, crystalline, non-hygroscopic powder, melting at 75° C. and having a bitter, aromatic taste. It is soluble in 20 parts of water at the ordinary temperature, but dissolves best in warm water; it is solu- ble in alcohol, chloroform, ether, and glycerin. Its solutions are neutral to test paper. It is decomposed by soluble hydroxides and carbonates and by strong acids. It is intended to be used as a substitute for guaiacol in cases in which the latter is indicated. In the form of ointment it has been recommended in acute articular rheumatism. Guaiacol Phosphate, (C 6 H r OCH 3 -0) 3 PO Guaiacol phosphate is a white crystalline powder, melting 98°, insoluble in water and ether, but dissolving in alcohol and chloroform. Guaiacol Phosphite, (CAOCHaO)^ Guaiacol phosphite melts 77-78° C, and is soluble in water and the organic solvents. Guaiacol Salicylate Guaiacol-salol is guaiacol salicylate, C6H4-OH-CO-0-(C6H4-OCH3), the salicylic acid ester of guaiacol, closely related to phenyl salicylate (salol) . It is a white crystalline powder, tasteless, but having a salol-like odor. It is insoluble in water, but soluble in alcohol, ether and chloroform.' It melts at 65° C. It is decomposed by alkalies and alkaline carbonates with the formation of alkali salicylate and alkali guaiacol. The alcoholic solution is colored wine red by the addition of ferric chloride, but if the alcoholic solution is dropped into a watery solution of ferric chloride a turbidity but no coloration is produced. Guaiacol Valerate, CeH^OCHs-OCOCA Geosote is a colorless or yellowish liquid boiling 265° C. Guaiacol Methyl Glycolate — Monotal Monotal is CH 2 (0-CH3)-COO.(C 6 H4-OCH3), the methyl-glycolic acid ester of guaiacol. It occurs as a limpid, colorless oil, of a faintly aromatic odor, easily soluble in alcohol, ether, benzol, and chloroform; difficultly soluble in water. It is soluble in about 6 parts of olive oil. It boils under 15 mm. ETHEREAL SALTS— PHENOLS 771 pressure at about 156° C. It is split up into guaiacol and methylglycolic acid when treated with caustic alkalies. Monotal is easily saponified by aqueous or alcoholic solutions of potas- sium hydroxide and then gives the reactions characteristic of guaiacol and methylglycolic acid. It has a specific gravity of 1.17 to 1.18 at 20° C. It is used as an analgesic. Potassium Guaiacol Sulphonate. Thiocol Thiocol is potassium guaiacol sulphonate, C6H 3 (OH)(OCH3)(KS03) 1:2:6. It is a colorless, crystalline powder, neutral or faintly alkaline, odor- less, and having a faint bitter, followed by a sweet taste. It is readily soluble in water, slightly soluble in ordinary alcohol, but insoluble in absolute alcohol and in ether or oils. Its aqueous solution is not precipi- tated by barium chloride; ferric chloride produces an intense violet-blue color, which disappears on the addition of ammonia, or of concentrated solution of alkali chlorides or sulphates. It is used in pulmonary tuberculosis, acute and chronic bronchitis, pneumonia, whooping cough, etc. Calcium Guaiacolmonosulphonate, Ca(C 6 H 3 OHOCH 3 S03)2 This salt, also known as guaiacyl, is a bluish-gray powder soluble in water and alcohol and used as an anesthetic. Methylene diguaiacol or geoform is a condensation product of form- aldehyde and guaiacol, and has been described in the chapter on " Alde- hydes/' An acetylated compound of geoform is called Euguform. Among the compounds of guaiacol and the alkaloids may be mentioned .piperidin guaiacolate or guaiaperol, melting 80° C, soluble in water, alcohol, and ether; quinin guaiacol bisulphonate or guaiaquin and quinin dihydrobromguaiacolate or guaiaquinol. Silver eosolate is the silver salt of trisulphoacetylguaiacol, C 6 HO • CH3 • OC2H3O • Ag 3 (S0 3 ) 3 , an antiseptic substance used in gonorrhea, in the form of an injection or in bougies. Calcium eosolate, the calcium salt of the same acid, Ca 3 (C 6 HO • CH 3 OC 2 H30(S03)3)2, is soluble in water and acids, and slightly in alcohol. Histosan is a guaiacol-albumin compound soluble in alkaline liquids. 772 ORGANIC SUBSTANCES Creosote Carbonate — Creosotal Creosote carbonate is a mixture of carbonic acid esters, analogous to guaiacol carbonate, prepared from creosote. It is a yellowish, thick, honey-like, perfectly clear and transparent liquid, containing 92 per cent of creosote. It is odorless and has a bland oily taste. It is insoluble in water, but soluble in alcohol, ether, chloro- form, benzene, and in fixed oils. The addition of a few drops of ferric chloride solution to the alcoholic solution should not cause any change in color. On boiling with potassium hydroxide solution the odor of creosote is evolved. Creosote carbonate has the same action as creosote, but is claimed to be non-toxic and devoid of irritant properties. It is recommended as a substitute for creosote for internal exhibition in tuberculosis, pneumonia, and as an intestinal antiseptic. Creosote phosphate is analogous to guaiacol phosphate, insoluble in water and alkalies. Creosote phosphite is called Phosphotal, is soluble in alcohol, water, and ether. Creosote tannate or Tanosal is an astringent antiseptic used for throat and bronchial troubles, soluble in water, alcohol, and glycerin, and insolu- ble in ether. Creosote valerate or Eosote is a colorless or yellowish liquid soluble in alcohol and ether. Creosote oleate is a yellowish oily liquid soluble in alcohol, ether, and chloroform. Methylenecreosote or Pneumin is a condensation product of creosote and formaldehyde. Creosote The creosote used for medicinal purposes is a mixture of phenols and phenol derivatives, which according to the Pharmacopoeia should be chiefly guaiacol and creosol, obtained by purifying a distillate of wood tar, chiefly that obtained from birch wood. It is a colorless or yellowish, highly refractive liquid with a smoky odor, soluble in alcohol, ether, chloroform, fixed and volatile oils, and miscible with considerable water to a cloudy liquid. Its saturated aqueous solution gives a transient violet- blue color, which soon changes to greenish and brown, with a brown pre- cipitate. It gives a reddish precipitate with bromin water. It is generally reported by investigators that creosote varies greatly in composition. Coal-tar creosote commonly consists of that portion of coal tar which distills between 200 to 300° together with the residual oils from the manu- ETHEREAL SALTS— PHENOLS 773 facture of crude carbolic acid, naphthalene, and anthracene. It usually contains naphthalene, phenanthrene, anthracene, diphenyl, and other solid hydrocarbons, carbolic acicl, cresols and other phenols, pyridine and other basic substances, and so-called undetermined indifferent oils. Hager's test for the detection of coal-tar products in wood creosote is as follows: One volume of the sample is agitated in a Mohr's burette with 3 volumes of diluted glycerol (1 vol. water to 3 vols, absolute glycerol) and the mixture allowed to stand until separation has occurred. If the creosote is pure the volume will remain unchanged. If reduced the gly- cerol layer is withdrawn and the treatment repeated and the volume again observed, the residual layer indicating the proportion of real wood creosote in the sample taken. The coal-tar products can be detected in the first glycerol fraction by filtering, diluting with water, and agitating the chloroform. On allowing the separated solvent to evaporate spon- taneously, the residue should be tested by shaking a portion with half its volume of an ethereal solution of collodion when, in the presence of much carbolic acid, the collodion will coagulate to a transparent jelly. If a drop of the residue is treated with a few drops of neutral ferric chloride in a small porcelain evaporating dish the reagent will assume a fine violet coloration. Homocatechol Methyl Ester or Creosol Creosol is homologous with guaiacol and occurs in that fraction of creosote boiling about 220° C. It is colorless when freshly distilled and has a vanilla-like odor. It is soluble in alkalies and a solution in strong alcoholic potash sets to a mass of needles of the potassium compound. It reduces silver nitrate on warming and gives a green color with ferric chloride, Dimethyl Homocatechol, C 6 H 3 CH 3 (OCH 3 ) 2 This body also occurs in beechwood creosote. It gives no color with ferric chloride and is insoluble in aqueous solutions of alkali hydroxides. 774 ORGANIC SUBSTANCES Catechol Monoethyl Ester /OC2H5 X)H This substance is closely related to guaiacol and is called Guaethol and also, though illogically, guaiacol ethyl. The last term is erroneous and confusing because it is not ethyl guaiacol. It is a colorless crystalline mass melting at 27 to 28° C, or an oily almond-colored liquid, with a pleasant aromatic odor. It boils at about 215° C, dissolves in alcohol, ether, and chloroform, but is insoluble in water. It is used for the same purposes as guaiacol. Resorcinol Resorcinol or meta-dihydroxybenzol has been recommended for a number of ailments, but its largest use is probably for aiding the removal of dandruff, and hence its presence may be expected in hair tonics and other mixtures designed to improve the condition of the scalp. Hair tonics may contain in addition to resorcinol, quinin, cantharides, extract of sage, precipitated sulphur, lead acetate, beta-naphthol, glycerin, and alcohol. Resorcinol is also used internally for asthma, hay fever, seasickness, whooping cough, diphtheria, etc., where remedies of an antiseptic, anti- pyretic, or antizymotic action are indicated. It is also applied in inflam- matory conditions of the mucous membrane of all parts of the 'body, and in erysipelas. It will be found in tablets with sodium bicarbonate and borax, and in ointments combined with other antiseptic agents. When pure, resorcin is a white crystalline substance, but on standing and especially on exposure to the light, it turns reddish. It melts 109- 111°, dissolves easily in water, alcohol, and ether, slightly in chloroform, benzol, and carbon bisulphide. Its aqueous solution gives a dark-violet color with ferric chloride, and a crystalline precipitate of tribromresor- cinol with bromin water, but no precipitate is given by lead acetate. It reduces ammoniacal copper and silver salts. When fused with phthalic anhydride the melt dissolves in sodium hydroxide with a beautiful green fluorescence due to the formation of a fluorescein. This reaction is characteristic of other meta-dihydric phenols. The trinitro-compound prepared as described under Thymol melts 175°; .1 gram resorcinol when boiled with 1 mil of potassium hydroxide to which a drop of chloroform is added develops a crimson color. A solution of resorcinol mixed with copper sulphate and sufficient ETHEREAL SALTS— PHENOLS 775 ammonia to redissolve the precipitate first produced, yields a deep black liquid which dyes wool and silk black. Resorcinol may be shaken out of its solution in ether by using dilute alkali, and on acidulating the latter, the resorcinol may be recovered by ether. In the general scheme of analysis it will appear when a residue left by shaking the aqueous acid solution with ether, is examined and it may be identified by applying the reactions above described. CM. Pence 1 has made a study of the methods of estimating resor- cinol, and recommends the following for assaying the commercial article: 1.4563 grams of the sample are dissolved in water and made up to 500 mils in a graduated flask. A 25-mil portion is transferred to a 500-mil glass-stoppered flask, 50 mils N/10 bromin added, 50 mils water and 5 mils concentrated hydrochloric acid, the mixture shaken and allowed to stand for one minute; 200 mils of water are then added, 5 mils of 20 per cent potassium iodide and after five minutes the liberated iodin is titrated with sodium thiosulphate. The number of mils of N/10 bromin solution consumed divided by .4 gives the percentage of resorcinol. A blank is run using 7 to 10 mils of potassium iodide. A mixture obtained by melting together equal parts of resorcin and iodoform is sold under the name of " Resorcinol." It is an amorphous brown powder, with an iodin odor, and is used as an antiseptic in oint- ments and dusting powders. Potassium diiodoresorcinol monosulphonate, C6Hl2(S03K)(OH)2, is used as an antiseptic under the name " Picrol." Resorcinol Monacetate or Euresol /OH C 6 H4< \)COCH3 Euresol is a thick, yellowish, oily liquid with an agreeable odor, boiling 283° C. It is soluble in acetone and in alkaline solutions, and is used in the treatment of chilblains, acne and as a substitute for resorcin in external application. Fluorescein Resorcinolphthalein— O : (C 6 H 3 OH) 2 : C-Cel^-COO. Fluorescein is prepared by the fusion of phthalic anhydride and resor- cinol at 195 to 200° C. till the mass becomes solid. This is extracted with water and the residue dissolved in potassium hydroxide solution, which is then filtered and the fluorescein precipitated with acid. It is an orange red powder, insoluble in water, ether, chloroform, and benzol; soluble in hot glacial acetic acid and boiling alcohol. It dissolves in alkaline solutions with formation of salts. 1 J. Ind. and Eng. Chem., 1911, 3, 820. 776 ORGANIC SUBSTANCES The alkaline solution by transmitted light is red; by reflected light it has a green flourescence even in very dilute solutions. When fluore- scein is boiled with chalk water, the calcium salt of fluorescein is formed which is recognized by its red-brown color and green sheen. The soluble sodium salt of fluorescein has been used for the diagnosis of corneal lesions and detection of minute foreign bodies imbedded in the cornea. Resorcinol-salol and resorcinol-eucalyptol are antiseptics. Resor- cinol-hexamethylenetetramine or Hetralin is used in gonorrhea and cystitis. Resorcmol is combined with mercury in a substance called mercury- resorcinol acetate, a yellow crystalline powder, soluble in alkalies and strong acids, and used as a hypodermic in syphilis, and in ointment form for local application. Resaldol Resaldol is the acetyl derivative of a condensation product of chlor- methylsalicylic aldehyde and resorcin. It is a yellow, amorphous, light powder insoluble in water, but soluble in alkalies. It is used as an intes- tinal antiseptic. Hydroquinone Hydroquinone, though used to a slight extent as an antiseptic and antipyretic, is best known as a photographic developing agent. Its most important feature in connection with drug chemistry is its relation to the glucosides and its appearance as a product of the hydrolysis of these principles. It is one of the products of the hydrolysis of arbutin. It forms colorless crystals, melting 169° C, dissolving easily in alcohol and ether and less readily in water. When its aqueous solution is treated with ferric chloride, fine green metallic crystals of quinhydrone, C6H402-C6H4(OH) 2 , appear, which can be crystallized pure out of boiling water. This substance dissolves in alcohol and ether to a yellow-colored solution and in ammonia to a green, which turns brown on exposure to the air. Hydroquinone-dimethyl ester, melting 56° C, is formed by boiling hydroquinone under pressure with methyl iodide and potassium hydroxide. Dihydroxytoluol or Orcinol /CH 3 1 CeHs^-OH 3 X)H 5 Orcinol occurs in many lichens, probably combined in complex acid or glucosidic combinations, and is freed on hydrolysis. It has been ETHEREAL SALTS— PHENOLS 777 obtained from some of the well-known vegetable colors, litmus, cudbear, and archil, and recovered from the alkaline fusion of aloes. It has a limited use as an antiseptic in skin diseases. Orcinol forms colorless crystals containing 1 molecule of water, which redden on exposure. It has a sweet but unpleasant taste. The crystals melt at 58-59° C, and lose all the water of crystallization below 100°. It dissolves readily in water, alcohol, and ether and the aqueous solution gives a violet color with ferric chloride. It forms a crystalline compound with ammonia, and when its ammonia- cal solution is exposed to the air it absorbs oxygen, giving a purple solu- tion from which acetic acid precipitates a red coloring matter called orcein. The new substance is sparingly soluble in water unless alkaline, but dis- solves in alcohol to a purple solution which is turned red by acid. Maltol, C 6 H 4 0(OH) 2 Maltol is a phenolic body which occurs naturally and which was for a long time confused with salicylic acid in testing for preservatives in malt liquors. It is difficultly soluble in cold water and benzol, but dis- solves easily in hot water, ether and alkalies, and is precipitated from the latter by carbon dioxide. Its aqueous solution gives a violet color with ferric chloride, reduces Fehling's solution and ammoniacal silver oxide. It does not, however, respond to test of Jorissen for salicylic acid, by which a red color is developed in the presence of this acid when 4 to 5 drops of 10 per cent potassium nitrite, 4 to 5 drops 50 per cent acetic acid and 1 drop of 10 per cent copper sulphate are added and shaken with the suspected sample. Maltol appears to be a reaction product resulting from the carameli- zation of carbohydrates. Trihydric Phenols The type compound of this group exists in three isomeric forms, all of which are well known bodies : OH OH OH /\)H (Aj /\ H OH Hol JoH OH Pyrogallol Phloroglucinol Hydroxyhydroquinone Pyrogallol Pyrogallol, called pyrogallic acid by the photographers, is used as an antiseptic in skin diseases. It may be obtained by heating gallic acid 778 ORGANIC SUBSTANCES with 2\ parts of water to 210° in an autoclave, or with glycerin to 195° until the evolution of carbon dioxide ceases. It crystallizes in fine needles, melting 132° C, boiling 210°, very solu- ble in water, alcohol, and ether, and turning brown and black in presence of alkaline solutions due to the rapid absorption of oxygen. Its aqueous solution gives with ferric chloride a red, and with ferrous sulphate con- taining a trace of ferric chloride a deep-blue solution. Pyrogallol has powerful reducing properties, precipitating silver and gold in the metallic state, and therefore being of value in photography, and as a hair dye. When heated with phthalic anhydride it yields gallein, which is used as a red dye, the alkaline solution being rose-red. (Blue, Allen.) When acetylated it yields triacetylpyrogallol, a substance known as Lenigallol, melting 165° C, insoluble in water, and dissolving in alkalies with decomposition. Lenigallol is used in psoriasis, eczema, and other skin diseases. A monoacetate is marketed as Eugallol. Both of these may be saponi- fied by alkalies, setting free pyrogallol, which of course is soon oxidized. Saligallol is said to be pyrogallol disalicylate. It is marketed in acetone solution. An oxidized pyrogallol is sold as a remedy for skin diseases. Phloroglucinol Phloroglucinol is intimately associated with the chemistry of some of the glucosides and resins. It results from the hydrolysis of phloridzin, a glucoside of the bark of the apple tree, and on fusing with potash, gam- boge, dragon's blood, kino, catechin, fustic, etc. In order to obtain it from the gums they are fused with potassium hydroxide until the melt is quiet, the mixture dissolved in water, acidified with sulphuric acid, and shaken with ether, which removes the phloro- glucinol and protocatechin or other acid resulting. After evaporating the ether, the residue is dissolved in water, the acid precipitated with a little lead acetate, the excess of lead removed by hydrogen sulphide and the phloroglucinol again extracted with ether. When resorcinol is fused with sodium hydroxide phloroglucinol results. It crystallizes in colorless prisms with two molecules of water which may be entirely driven off at 100°. The anhydrous body melts 218-220° but a specimen will often begin to melt at 200° if heated slowly. It sub- limes easily, is readily soluble in water, to which it imparts a sweet taste, and dissolves easily in alcohol and ether. Its aqueous solution is colored bluish violet by ferric chloride. It reduces Fehling's solution. Its solu- tion in hydrochloric acid stains wood violet-red. Its alkaline solutions rapidly turns brown in contact with air owing to absorption of oxygen. ETHEREAL SALTS— PHENOLS 779 A cold solution of phloroglucinol in acetic acid reacts with potassium nitrite to form the trinitrosophloroglucinol, which separates on addition of potassium hydroxide and alcohol in the form of its potassium salt, a green, crystalline, explosive body. Phloroglucinol, when dissolved in sulphuric acid and added to a mix- ture of nitric and sulphuric acids, yields the tri-nitro derivative melting 165 to 166° C. It is a yellow, explosive body which dyes wool and silk yellow. When digested with acetyl chloride it yields the triacetyl derivative, melting 106°. By the .phthalein fusion it gives a blue color on adding alkalies. While in most of its reactions phloroglucinol behaves as symmetrical trihydroxy benzol, it also acts like a triketone, as it gives a trioxime, CeH6(NOH)3, with hydroxylamine. It is possible that it exists in tauto- meric forms, the second being represented by H 5 H 2 1° O a triketone of hexamethylene. Phloroglucinol will be found occasionally in medicines intended for antiseptic, antipyretic, and tonic purposes. Hydroxyhydroquinone This phenol is prepared from pyrogallol by fusion with potash pre- cisely as phloroglucinol is obtained from resorcinol. It melts 140°, is readily soluble in water, and its aqueous solution is colored greenish brown by ferric chloride, changing to blue and red on adding sodium carbonate. THE NAPHTHOLS Alpha- and beta-naphthol are monohydroxy derivatives of naphthalene and correspond with the monohydric phenols. Their properties are in many respects similar to those of the phenols; they dissolve in alkalies, forming metallic derivatives which are decomposed by acids and carbon dioxide, and yield acetyl and alkyl derivatives on the hydroxyl group. In other ways, however, the hydroxyl group is shown to be more sensitive than in the phenols, for heating with ammonia-zinc chloride to 250° the 780 ORGANIC SUBSTANCES corresponding amido compound is produced, the same reaction with phenol requiring a much higher temperature, and when heated with an alcohol and hydrogen chloride alkyl derivatives result. Both a- and /3-naphthol are of medicinal importance, but the latter and its derivatives have probably the most extensive use. They are anti- septic and germicidal in action and are used in ointments and washes in skin diseases, and internally are employed in the treatment of typhoid fever, chronic diarrhea, smallpox, scarlet fever, measles, etc. Alpha- naphthol is reported to be somewhat more powerful and weak solutions are credited with preventing the development of the spores of the tubercle bacilli. Alpha-naphthol is a colorless crystalline substance with a faint phenol odor, melting 94°, boiling 278-280° C, readily soluble in alcohol and ether, but sparingly only in hot water. Its aqueous solution gives a scanty white or purplish-white precipitate with ferric chloride or a reddish color turning violet. It is readily acted on by nitric acid, yielding a dinitro derivative, CioH5(N02)2-OH, which crystallizes in yellow needles, melting at 130°, possessing marked acid properties, decomposing carbonates and "forming deep yellow salts which dye silk a golden yellow. The sodium compound, CioH 5 (N02)20Na+H 2 0, is known as Martius yellow. When .5 gram of alpha-naphthol is dissolved in 10 mils of 1 per cent sodium hydroxide and boiled for one-half minute with 5 drops of chloro- form a blue color appears, changing to bluish green and on standing four to five hours to a yellow green. If .1 gram is mixed with .15 gram of picric acid and treated with 10 mils of boiling dilute alcohol (1 : 1) a picrate is formed, which when filtered, washed and dried on a porous plate melts on rapid heating at 188.5 to 189.5° C. An aqueous solution of calcium hypochlorite gives a dark violet color changing to reddish brown. Beta-naphthol forms colorless laminae, melting 122° and boiling 285-6° C, soluble in alcohol, ether, chloroform, and fixed oils, but only slightly in cold water. Its aqueous solution gives an opalescence with ferric chloride or a pale-green tint. Its picrate, prepared as above, melts 155.5 to 156.8° C. When boiled with sodium hydroxide and chloroform a blue color is obtained which fades rapidly. Calcium hypochlorite in aqueous solution gives a pale yellow color, destroyed on adding excess of the reagent. Reuter has described a test for distinguishing between naphthalene and the two naphthols, using chloral hydrate as a reagent: One-tenth gram of the sample is mixed with 2.5 grams chloral hydrate and warmed for ten minutes; and simultaneous tests are run using in addition 5 drops ETHEREAL SALTS— PHENOLS 781 of strong hydrochloric acid in the one case and the same amount of acid and a piece of zinc in the other. The results are as follows: Naphthalene a-Naphthol /3-Naphthol Chloral Hydrate Colorless Ruby red, trans- parent, not flu- orescent Pure blue, trans- parent, not flu- orescent Chloral Hydrate +HC1 Very slight pink Intense dark greenish blue, not transparent Intensely yellow, transparent Chloral Hydrate +HCl+Zn Violet to brown Dark violet blue. Water throws out a violet floc- culent precipi- tate. Alcohohc solution violet with fluores- cence Dark brown. Water throws out a greasy pre- cipitate. Alco- holic solution yellow with blue fluorescence When a small quantity of the sample is treated with 2 mils of iodin in potassium iodide and an excess of sodium hydroxide added, alpha- naphthol gives a turbid liquid of an intensely violet coloration, and beta- naphthol a clear colorless liquid. Estimation of Beta-Naphthol Kuster x recommends digesting a weighed quantity of the sample in a sealed flask with reduced pressure, on a water-bath with a measured quantity of a saturated aqueous solution of picric acid. The naphthol is converted quantitatively into an insoluble picrate and the amount of picric acid remaining in solution is ascertained by titrating an aliquot portion with N/10 barium hydroxide. The picrate formed is slightly soluble in water, so that it is necessary to allow .0075 gram of beta- naphthol per 100 mils of the picric acid solution used. Messinger and Vortmann's iodometric method for determining phenols has been adapted to beta-naphthol. Three grams of the sample are dis- solved in a solution of not less than 3.5 grams sodium hydroxide and diluted to a known volume, not less than 250 mils. A 10-mil aliquot is placed in a small flask, heated to 55° C. and N/10 iodin added until the solution shows a yellow color. A greenish precipitate will settle on shaking. The cooled liquid is acidified with dilute sulphuric acid, made up to 250 mils and an aliquot titrated with sodium thiosulphate. The figure for the iBer., 1894,27, 1101. 782 ORGANIC SUBSTANCES iodin actually used calculated to the whole amount taken and multi- plied by .3784 will give the amount of beta-naphthol present. Alphol Alphol is the salicylic ester of alpha-naphthol, C6H4(OH)COOCio07. It is a reddish-white crystalline powder, melting 83° C, insoluble in water, but soluble in alcohol, ether, and fixed oils. It is used as an antiseptic and antirheumatic. Most of the naphthol derivatives which are encountered in practice are of beta-naphthol. Alumnol Aluminum Beta-naphthol-Disulphonate, A^CioHs- OH -(803)2)3, the aluminum salt of beta-naphthol-disulphonic acid. It forms a fine, nearly white, non-hygroscopic powder, soluble in 1.5 parts of water, forming a faintly acid and slightly fluorescent solution. It is easily soluble in glycerin, but sparingly soluble in alcohol and insoluble in ether. When dried it loses about 9 per cent of water, and when exposed to the air it is darkened in consequence of its reducing prop- erties. It is precipitated from solution by albuminous and gelatinous bodies, but these precipitates are redissolved in excess of the latter bodies. The dried compound should yield 12.7 per cent of ash (alumina) on incineration. It is an astringent and mild antiseptic. Beta-Naphthol Benzoate, C 6 H 5 • COO • Ci H 7 It forms colorless needles, or a white crystalline powder, colorless and tasteless, melting at 110° C. It is almost insoluble in water, but readily soluble in alcohol and in ether; also soluble in chloroform, in glycerin and in olive oil. It is decomposed by heating with caustic alkalies into naphthol and a benzoate which will then give their characteristic reactions. To test beta-naphthol benzoate for the presence of beta-naphthol it should be shaken several times with dilute solution of sodium hydroxide (1 : 10) and immediately filtered. If beta-naphthol is present in con- siderable amount it will separate as a turbidity or precipitate after acidify- ing with dilute sulphuric acid. If the amount of beta-naphthol is small no precipitate appears, but the alkaline solution shows a bluish fluor- escence and if it is boiled with chloroform a green color is produced. It is used internally as an intestinal antiseptic in diarrhea and typhoid fever. Externally it is said to be useful as a parasiticide in the form of 3 to 10 per cent ointment. ETHEREAL SALTS— PHENOLS 783 Betol Naphthalol — Naphthol-Salol— Salinaphthol. Betol is beta-naphthyl salicylate, C6H4 • OH • CO • • (C10H7) , the salicylic acid ester of beta- naphthol. It is a white, shining crystalline powder, colorless and tasteless, melting at 95° C. It is insoluble in cold or hot water or glycerin, difficultly soluble in cold alcohol or turpentine, easily soluble in boiling alcohol, in ether, in benzene, and in warm linseed oil. In the cold it is not changed by acids or alkalies of moderate concentration. When heated with alkalies it is decomposed into its constituents, which, if the solution is acidulated, will crystallize. It is distinguished from salol by its higher melting-point and by the production of a brownish-green color, when a trace of nitric acid is added to its yellow-colored solution in pure sulphuric acid. Bismuth Beta-Naphtholate Bismuth beta-naphtholate occurs in the form of a brownish or grayish powder without odor, almost tasteless and insoluble in water. It is slightly soluble in alcohol. From 1 to 2 grams of bismuth beta-naphtholate is shaken in a separator during one hour with 25 mils of chloroform and 25 mils of concentrated hydrochloric acid, and then 50 mils of water added and the mixture again shaken. The chloroform solution is then drawn off and the acid mixture extracted with three more portions of 10 mils each of chloroform and the combined extracts evaporated and dried to constant weight over sulphuric acid. A residue should remain, weighing at least 15 per cent of the material used, which should respond to tests of identity for beta-naphthol. If bismuth beta-naphtholate is examined by the method given below, the bismuth oxide found should weigh not less than 60 per cent of the material taken. The acid solution from which the naphthol has been extracted is trans- ferred to a beaker, diluted to 200 mils, heated to boiling, ammonia water added till turbidity appears, then sufficient hydrochloric acid to clear up the turbidity, and then 50 mils of 10 per cent ammonium phosphate solu- tion is added to the boiling liquid. The precipitate is allowed to subside, the clear liquid decanted through a tared porcelain Gooch crucible, the precipitate washed with hot water by decantation and finally transferred completely to the crucible. The precipitate and crucible are dried, placed in a nickel crucible, and exposed to the full heat of a Bunsen flame till the weight is constant. The weight of the resulting bismuth phosphate multi- plied by .6869 should yield a figure (representing bismuth, Bi) equal to not less than 60 per cent of the material taken. 784 ORGANIC SUBSTANCES It is used in catarrhal and fermentative gastroenteric disorders, such as gastritis, dysentery, and diarrhea. Diiodobetanaphthol, CioH 6 I 2 2 Iodonaphthol or naphtholaristol is a yellowish-green powder which decomposes on heating with evolution of violet fumes. It is insoluble in water, and only slightly in alcohol and ether, but dissolves readily in chloroform. Betanaphthol Lactate This substance, known as Lactol, is used as an antiseptic. Sodium betanaphtholate is called Microcidin, and is employed as a constitutent of surgical dressings, and in antiseptic sprays for nose and throat diseases. The naphthols combine with sulphuric acid to form a series of sulphonic acids. The calcium salt of beta-naphthol sulphonic acid is called Abrastol or Asaprol, a reddish-white powder, soluble in water and alcohol, and decomposing at about 50° C. It has antiseptic, analgesic, and antipyretic properties and may be found occasionally in medicinal analysis. Detection of Abrastol. — Sinibaldi's Method. — Make 50 mils of the sample alkaline with a few drops of ammonium hydroxide and extract with 10 mils of amyl alcohol (ethyl alcohol is added if an emulsion is formed) . Decant the amyl alcohol, filter if turbid, and evaporate to dry- ness. Add to the residue 2 mils of a mixture of equal parts of strong nitric acid and water, heat on the water-bath until half of the water is evaporated, and transfer to a test-tube with the addition of 1 mil of water. Add about .2 mil of ferrous sulphate and an excess of ammonium hydroxide, drop by drop, with constant shaking. If the resulting precipitate is of a reddish color, dissolve in a few drops of sulphuric acid, and add ferrous sulphate and ammonium hydroxide as before. As soon as a dark-colored or greenish precipitate has been obtained introduce 5 mils of alcohol, dis- solve the precipitate in sulphuric acid, and shake the fluid well and filter. In the absence of abrastol this method gives a colorless or fight-yellow liquid, while a red color is produced in the presence of .01 gram of abrastol. There are several phenols or phenol ethers occurring in essential oils which are in somewhat close realtionship, as they are all either allyl or propenyl derivatives of benzol. They usually have characteristic odors different in each case, and are the main ingredients identifying the par- ticular oils in which they occur. It is impossible to describe these odors, ETHEREAL SALTS— PHENOLS 785 but when one becomes familiar with them they furnish the best evidence of their presence, and unless one is dealing with a straight oil, or has a sufficiently large sample, -this odor is the best and often the only means of identification. Chavicol, C 6 H 4 (CH 2 CH = CH 2 )OH, 1-4 Chavicol is a colorless liquid boiling about 237° with specific gravity 1.033 at 18°, occurring in bay and betel leaf oils. Its aqueous solution gives a deep-blue color with ferric chloride. Methyl Chavicol, C 6 H 4 (CH 2 CH = CH 2 )OCH s , 1-4 Methyl chavicol is a colorless liquid with a faint anise-like odor, boiling 215-216° C, sp. gr. .9714 to .972 at 15° C. It occurs in the oils of anise, star anise, fennel, bay, and basil oils. It is isomeric with anethol, which is the propenyl derivative, and may be converted to anethol by boiling with alcoholic potash. Estragol is also isomeric with methyl chavicol and occurs in tarragon oil. Anethol, C 6 H 4 (CH = CHCH3)OCH 3 , 1-4 Anethol, or paramethyxypropenylbenzene, is also called anise cam- phor. It is a white crystalline substance with a strong anise-like odor, melting 21° C, boiling 233-234°, sp. gr. .985 to .986 at 21 to 25° C. It gives a well-defined bromin compound monobrom anethol dibromide, which melts 107 to 108° C. Anethol is the chief constituent of anise and star anise oils and is present in fennel. Safrol, C 6 H 3 (CH 2 CH = CH 2 )OOCH 2 , 1-3-4 Safrol is the methylene ester of allyl pyrocatechol and is a colorless or faintly yellow liquid with a characteristic odor of sassafras. It boils 233°, sp. gr. 1.108 at 15° C, and on cooling yields crystals which melt at 11° C. When oxidized with chromic acid piperonal (heliotropin) and piperonylic acid C 6 H 3 OOCH 2 • COOH result. Safrol is the characteristic and chief component of sassafras oil, and occurs in camphor oil. It has some use in medicine as a tonic, aromatic, and carminative. By proper treatment it is transformed into the propenyl derivative isosafrol, C 6 H 3 (CH = CH-CH3)OOCH 2 . Eugenol, C 6 H 3 (CH 2 CH = CH 2 )OCH 3 OH, 1, 3, 4 Eugenol is paraoxymetamethoxyallylbenzene, and is also called eugenic or caryophyllic acid. It is a faintly yellow liquid with the odor of cloves, 786 ORGANIC SUBSTANCES it boils 252° at 749 mm., sp. gr. 1.072 at 15°. Its alcoholic solution gives a bluish-green color with ferric chloride, but it gives only a transient grayish green in aqueous solution. Upon oxidation it yields vanillin and vanillic acid, and when treated with benzoyl chloride a benzoic ester is produced which melts 69-70° C. Isoeugenol, boiling 260° C, the propenyl derivative, results on molec- ular rearrangement by boiling with alcoholic potash. Isoeugenol gives a blue-green with ferric chloride. Eugenol is soluble in alkalies and when shaken with ammonia is converted into a yellow crystalline mass. A drop of concentrated sulphuric acid added to 10 drops of eugenol produces a blue color changing to purple on adding more acid. Eugenol is an important constituent of clove oil and is also found in many others, including cinnamon, sassafras, pimento, bay, camphor, etc. It has antiseptic properties and is used as an ointment in skin diseases and tubercular affections and as an antiseptic in dentistry. Methyl Eugenol, C 6 H 3 (CH 2 CH = CH 2 )(OCH 3 )(OCH 3 ), 1, 3, 4 Methyl eugenol has a less powerful though similar odor to eugenol, and boils 248-249°. It gives a bromin derivative melting 78° and on oxidation with permanganate is converted into veratric acid, melting 179-180°. It occurs in bay, citronella, hazelwort, paracoto bark, and other oils. Eugenoform Eugenoform is the sodium salt of a product obtained by the action of. formaldehyde on eugenol. It forms colorless crystals soluble in water and alcohol and is used as an intestinal antiseptic in cholera and typhoid fever, and as a disinfectant. Eugenol Benzoate Benzoeugenol forms white crystals melting 68-70° C, soluble in alcohol, ether, and chloroform and is used in tuberculosis and for neuralgia. Eugenol Cinnamate The ester, melting 90°, forms odorless and tasteless shining needles soluble in ether, chloroform, and hot alcohol. It is used as an antiseptic in tuberculosis. Asarol, C 6 H 2 (CH = CHCH 3 )(OCH 3 )3 Ararol, asaronic, or asarum camphor, is propenyl trimethoxy benzene and occurs in the oils of hazelwort (Asarum europeum) and matico. It is an emetic and cathartic. Asarol melts 62° and yields a dibromide melting 85-86° C. ETHEREAL SALTS— PHENOLS 787 Apiol, C 6 H(CH 2 • CH = CH 2 ) (OCH 3 ) 2 OOCH 2 Apiol or parsley camphor is obtained from oil of parsley seed, Petro- selium sativum, in which it occurs to the amount of about 25 per cent. It also occurs in the oil of the seeds and roots of celery, Apium graveolens. It crystallizes from ether, melting 36° and boils 294°. It is insoluble in toater but dissolves in alcohol, ether, fixed, and volatile oils. Oxidizing agents convert it to apiol aldehyde, and on prolonged treatment to apiolic acid. By the action of nitric acid it is partially converted to oxalic acid and partly to a crystalline yellow nitro compound melting 116° C. Bro- min in carbon bisulphide acts on apiol to produce tribromapiol, which may be crystallized out of alcohol, melting 88° C. Commercial apiol has an oily consistency and is of varying composi- tion. It is used as an emmenagogue and antiperiodic and is dispensed in capsules and in oily solutions, usually olive oil. Celery is used in dropsy and rheumatism and to a large extent in nerve tonics. When apiol is boiled with alcoholic potash it is converted into isoapiol, the propenyl derivative, melting 56° and boiling 304°. It occurs in dill camphor. Saligenin, C 6 H 4 OHCH 2 OH Saligenin is ortho-oxybenzyl alcohol and has the characters of both a phenol and an alcohol. It is one of the products of the hydrolysis of salicin, and can be prepared synthetically from carbolic acid and form- aldehyde. It forms colorless to yellowish crystals, melting 86°, subliming 100°, soluble in alcohol, ether, and hot water. Its alcoholic solution gives a reddish- violet color with ferric chloride changing to yellow. With concentrated sulphuric acid a red color is produced. When boiled with anilin, oxybenzyl anilin is produced, melting 108°. Saligenin is chiefly important as a means of identifying salicin, but it is also used to a slight extent as an antirheumatic. Homosaligenin, C 6 H 3 • CH 3 CH 2 OH • OH, 1, 2, 4 Homosaligenin melts 105°, gives a blue color with ferric chloride, and on boiling with dilute hydrochloric acid yields homo-saliretin, melting 200-205° C. Diosphenol and Buchu The leaves of Barosma betulina (Rutacese) are recognized as the official buchu. The therapeutic value of the drug is due probably to an essential oil, which contains as its chemically recognizable constituent, a phenolic and ketone-like body called diosphenol. The same or closely allied oil is present in the leaves of B. crenulata, which, however, is con- 788 ORGANIC SUBSTANCES sidered an adulterant of official buchu. It would be impossible, however, to detect the difference between these drugs in the extract form, the state in which they occur in medicinal preparations. Buchu is valuable chiefly as a diuretic and is usually combined with some other kidney stimulant such as Juniper berries, potassium nitrate, triticum, and cornsilk. It will be found in many of the proprietary remedies recommended for kidney troubles, and is a constant component of kidney pills, and is often present in the trick pills containing methylene blue, which are used to deceive the unwary regarding the condition of their urine. Liquid preparations contain buchu combined with juniper berries, cubeb, uva ursi, and nitrous ether; with juniper berries and potassium acetate; with Collinsonia, juniper berries, and Pareira; and small quan- tities of buchu are present in the " Buchu Gins " which used to be widely sold as medicinal beverages. Extract of buchu is present in cystitis pills combined with boric acid, triticum, cornsilk, Hydrangea, atropin, and potassium bicarbonate or benzoic acid, or Viburnum prunifolium. It is also combined with Hyoscyamus and potassium bicarbonate; and with Digitalis, squill, and potassium nitrate; and is present in certain capsule formulas combined with cubebs and copaiba. In commerce round and long buchu leaves are distinguished; the first are those of B. betulina and B. crenulata; the second those of B. serrati- folia. E. M. Holmes reports the finding of three different species of leaves which clpsely resemble official buchu, and which might functionate as adulterants. The chief points of difference are as follows: Empleurum serrulatum, leaves acutely jointed, no gland at apex, odor different, and fruit consists of a single follicle with a sword-shaped beak: Barosma echloniana, leaves with rounded base, broader in proportion, thickened margin with very shallow crenulations, no gland at the very obtuse apex and a peculiar dull surface, the flowers have about six purplish glands on each petal: Psoralia obliqua, oblique or unequal sided lamina, recurved apiculus, veins hairy, and difference in structure of the oil glands. The leaves of B. betulina yield on distillation from 1.3 to 2 per cent of oil, and from this the characteristic principle diosphenol separates on standing. The oil has a camphoraceous and mint-like odor. Diosphenol is called buchu camphor. It is a colorless crystalline substance meiting 82°, boiling 232°, or at 112° under 14 mm., and has the properties of both a phenol and a ketone. It may be extracted from oil of buchu by alkalies, from which it is repre- cipitated by acids, and forms an oxime and hydrazone. It gives a dark- green color with ferric chloride. The presence of buchu is usually apparent by its characteristic odor. ETHEREAL SALTS— PHENOLS 789 This odor and the identification of the diosphenol in preparations contain- ing appreciable quantities of buchu are the only means at present for identi- fying the drug. The odor should, of course, be compared with that evolved by a known sample. When the sample under examination is a pill or tablet, the characteristic constitutents of buchu can be separated by grinding, macerating with water, and subjecting to steam distillation. The distillate will contain the essential oil of buchu recognizable by its odor and on shaking with ether this will dissolve. From the ethereal solution the diosphenol can be shaken out with alkali, and recovered by acidulating and extracting with ether. Juniper oil will appear in the distillate if present originally in the sample and if in large amount may disguise the buchu, but the procedure for separating the diosphenol will eliminate the juniper constituents and enable one to detect the buchu, provided there is enough of it present. Detection of Diosphenol Make about 300 mils of the liquor distinctly acid and distill, taking off three fractions of about 100 mils each. Saturate the third fraction with salt and shake out with ether. Evaporate the ether in vacuo, take up residue in 4 to 5 drops of alcohol, add 1 to 2 drops alcoholic ferric chloride — a green color indicates buchu. Confirmatory test can be made by testing a similar residue obtained as above with ammoniacal silver nitrate which should be reduced. Juniper Communis Extract of juniper berries and the oil of that fruit, are conveniently considered at this point in connection with buchu. The distilled oil and extract of Juniper communis (Pinacese) and probably of J. sibirica are chiefly used as adjuvants to more powerful diuretics in dropsical com- plaints, and to round out the formulas of pills and tablets designed to correct a deranged condition of the kidneys and genito-urinary tract. The combinations of juniper and buchu will be found under the dis- cussion of the latter drug, and as a general thing either juniper or buchu and often both together will be found in any proprietary remedy adver- tised as a remedy for diseases of the kidneys. Juniper is one of the com- ponents of elixirs of the " Swamp Root " type, where it is combined with emodin-bearing drugs, aromatic balsams, methyl salicylate, oil of card- amom, and cubeb. Juniper oil has a characteristic odor and has been found to contain pinene and cadinene. Its specific gravity lies between .865 to .882, and it is usually laevogyrate up to -11°. It is miscible with all the organic solvents except diluted alcohol. CHAPTER XX SYNTHETIC ORGANIC NITROGEN COMPOUNDS AMINES, DIAMINES AND AMIDES The nitrogen compounds in organic chemistry include numberless individuals. We have already considered a large class of them under the alkaloids, and the following discussion is concerned with those nitro- genous medicinal agents which are prepared synthetically. ALIPHATIC NITROGENOUS COMPOUNDS The simplest representatives of this group may be considered as sub- stituted products of ammonia in which one or more of the hydrogens is replaced by an alkyl radicle. These bodies are called amines, and are primary, secondary, or tertiary, according as one, two, or three atoms of hydrogen has been displaced. The lower members are gases or low- boiling liquids and are strong bases, usually stronger than ammonia, fuming with nitric acid, combustible (thereby differing from ammonia), and forming double compounds with gold and platinum chlorides. The primary amines give the carbylamine reaction; and are converted by nitrous acid into primary alcohols with evolution of nitrogen. The secondary amines do not give the carbylamine reaction, and on treatment with nitrous acid yield a nitrosamine, which is detected by Liebermann's reaction. In order to perform this test the nitrosamine is separated and treated with concentrated sulphuric acid; a dark-green solution results which, after diluting with water, becomes red, and on adding excess of alkali assumes a blue or green color. The tertiary amines usually remain unchanged in presence of nitrous acid. Moureu and Magnonac recommend the use of ethyl magnesium bromide for distinguishing the amines. When the reagent is dissolved in ether it reacts with primary and secondary amines in ether with the liberation of one molecule of C2H6 for each amine group present in the molecule. No reaction takes place with tertiary amines. The amines occur among the decomposition products of animal and vegetable products, and in our work may be of moment only in rare instances; for example, in the examination of extracts of cod livers, or of oils prepared from animal matter which is in a state of partial decom- position. 790 SYNTHETIC ORGANIC NITROGEN COMPOUNDS 791 Hydrazine, H2N NH2, is the parent substance of a large number of derivatives, some of which are of considerable importance. Hydrazine sulphate, NH2 • NH • H2SO4, called diamidogen or diamine sulphate, is a white crystalline solid, soluble in water and used as an anti- septic and fungicide. Phenylhydrazine, C 6 H 5 NHNH 2 Phenylhydrazine is either a slightly yellow oil or a colorless crystalline mass, melting 23°. It boils with evolution of ammonia at 241-242°, and distills unchanged at 120° under 12 millimeters pressure. It is sparingly soluble in cold water, more readily in hot, and is veiy soluble in alcohol, ether, chloroform, and benzol. It is easily oxidized on exposure to air, becoming red and finally dark brown. It has strong basic properties and forms salts with acids and carbon dioxide. A solution of the hydro- chloride reduces salts of silver, mercury, gold, platinum, and Fehling's solution in the cold, in the latter case nitrogen is evolved, and cuprous oxide precipitated, and anilin and benzol produced. When the hydrochloride is treated with a cold solution of potassium nitrite, a yellow nitroso comp., C6Hs(NO)NNH2, separates, which on treatment with carbolic acid and strong sulphuric acid, yields a brown solution changing to green and blue. Phenylhydrazine has well-marked antiseptic properties, and has been recommended as a substitute for mercuric chloride. A solution of a salt of phenylhydrazine on treatment with caustic alkali yields a precipitate of the free base which is removable by shaking out with ether. Phenylhydrazine reacts with aldehydes and ketones to form hydra- zones, and when heated with excess of the reagent if the substance contains an OH group a second molecule reacts, producing osazones. It also forms hydrazides with hydroxy acids of the sugar group which have the general formula RCOHNNHC 6 H 5 , Phenylhydrazine may be prepared from anilin by diazotizing and subsequently reducing the product thus obtained. It is interesting to note that under a strained interpretation of the term derivative, the well- known antipyrin could be considered a derivative of acetanilid because antipyrin can be prepared from phenylhydrazine, and anilin is one of the products of hydrolysis of acetanilid. ANTITHERMIN CH 3 C(N • NHC 6 H 5 )CH 2 • CH 2 • COOH is the hydrazone of acetopropionic acid, which is CH3COCH2CH2COOH. It forms colorless, odorless crystals from alcohol, melting 108°, nearly insoluble in water, but soluble in alcohol, ether, and dilute acid. It is 792 ORGANIC SUBSTANCES decomposed by alkalies with liberation of phenylhydrazine. It is used as an antiseptic and also in phthisis and Blight's disease. Hydracetin is the acetyl derivative of phenylhydrazine, CeHsHNNH (C2H3O), and is a colorless, crystalline powder, melting 128°, soluble in alcohol and hot water, and slightly in ether. It is used as an antipyretic in rheumatic fevers, and externally in psoriasis and skin diseases. Antipyrin — 1 phenyl 2 — 3-dimethyl pyrazolone /CO CH /C=CH C 6 H 5 N< / or C 6 H 5 N< >0 I \N— C-CH 3 X N^==C I I I CH 3 CH3 CH3 Antipyrin, known also as phenazone, analgesine, metozine, parodyne, phenylone, anodynine, antipyreticum, pyrazoline, sedatine, etc., has an extensive use in medicine as an antiseptic and analgesic, and to some extent as a hemostatic. It is used either by itself or in admixture for bilious and nervous headache, whooping-cough, puerpural fever, sea- sickness, gout, sciatica and neuralgic conditions. As a styptic it is used principally for hemorrhoids. It will often be found in tablets or elixirs mixed with caffein and the bromides, and occasionally acetanilid, acet- phenetidin or codein will be included. When phenylhydrazine reacts with ethyl aceto-acetate there ulti- mately is formed 1-3 phenylmethyl pyrazolone. CH 3 COCH 2 COOC 2 H 5 +C6H 5 HNNH 2 = CH 3 C(NNHC 6 H5)CH 2 COOC 2 H5+H 2 CH3C(NNHC6H5)CH 2 COOC2H5+heat .CO— CH 2 = C 6 H 5 N< I +C2H3OH X N=C— CH 3 On methylating the new substance with methyl iodide antipyrin results. The first formula given above has been ascribed to Knorr and the second to Michaelis. Antipyrin crystallizes in small, lustrous, rhombic needles or plates, odorless, and with a somewhat bitter taste, melting 113-114° unless it contains hygroscopic moisture, which reduces the melting-point to 105- 107°, and which may be driven off at 100°. It sublimes when exposed to a temperature of 100°. It is very soluble in water, alcohol, and chloro- form, very moderately soluble in ether, and but slightly in petroleum ether. It is removed from both acid and alkaline solutions by immiscible solvents, chloroform being the most efficacious and usually preferred in analytical work. Its aqueous solution is alkaline to methyl orange, but not to either litmus or phenolphthalein. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 793 Antipyrin precipitates with a number of the alkaloidal reagents, including potassium mercuric iodide, iodin, picric acid, bromin water mercuric nitrate, potassium bismuth and potassium cadmium iodides, sodium phosphomolybdate, silicotungstic acid, and tannic acid. Antipyrin dissolves in nitric acid with a yellowish color and on evapor- ating on the steam-bath a purple color develops. If the reaction is checked and water added, a violet precipitate is thrown down and the liquid is reddish purple in color. The purple coloration which results on evapo- rating with nitric acid will mask any test for atropin or strychnin which is subsequently made with alcohol potash. When nitrous acid is added to a solution of antipyrin a green color is produced, and if the antipyrin is in quantity a precipitate of green crystals is obtained. The green substance which is visible at consider- able dilution is due to isonitrosoantipyrin. On heating the liquid the color will change to purplish red. This test is best performed by dis- solving a soluble nitrite in a little water, acidifying with sulphuric acid and then adding a solution of the suspected substance. It is not character- istic of antipyrin being given by other pyrazolones, but it is not given by acetanilid or the phenetidines. Pyramidon gives a blue to violet. Antipyrin in dilute solution gives a blood-red color with 1 per cent ferric chloride solution. It is destroyed by excess of mineral acids. It forms certain well-defined salts which are useful in substantiating its identification. The picrate, which is very insoluble in water, forms yellow crystals, melting 188°, the platinochloride. ferrocyanide and salicylate, the latter melting 91-92°. Steensma x has described a reaction of antipyrin with p-dimethyl- aminobenzaldehyde which is useful for detecting small quantities of the substance, especially in toxicological work. The reagent consists of 1 gram of the above-mentioned substance, 5 mils of 25 per cent hydro- chloric acid, and 95 mils absolute alcohol. A trace of the residue suspected of containing antipyrin is dissolved in a few mils of the reagent and evaporated in a porcelain dish, when a residue with red patches or a red ring is obtained. If the amount is extremely minute the reagent should be diluted with an equal volume of absolute alcohol. Pyramidon gives no color reaction, but salipyrin and acetopyrin react like antipyrin. Primot 2 reports a reaction with vanillin which is carried out in the same way as the above test. The reagent is prepared by dissolving 1 gram vanillin in 6 mils dilute hydrochloric acid (1-1) and 94 mils of 95 per cent alcohol. If antipyrin is present the residue is characterized by a deep-orange ring and an orange deposit. Pyramidon does not show this color. Cryogenin (metabenzaminocarbazide) gives a yellow- green tint under the same conditions. 1 Apoth. Zeit., 1097, 22, 819. 2 Bull. Soc. Pharmacol., 1909, 370. 794 ORGANIC SUBSTANCES In the general scheme of analysis antipyrin will appear in consider- able quantity in the residue left on evaporating the chloroform extraction from an acid solution. Traces of an alkaloid-like substance will have been evident in the previous fractions resulting from the petroleum ether, and ether extraction, but antipyrin is not removed to any extent by either of these solvents. If the residue left on evaporating the chloro- form is syrupy in appearance and crystallizes in frostlike forms on cool- ing, and if it dissolves readily in water, gives a precipitate with potassium mercuric iodide, a green color with nitrous acid, a yellow picrate, melting 188°, and deep purple on evaporation with nitric acid, the analyst can feel satisfied that he has found antipyrin. Pyramidon is the only substance in common use which might be mistaken for antipyrin. It melts, however, at 108°, gives a bluish- violet color with ferric chloride, a blue to violet with nitrous acid, and reduces silver nitrate after first yielding a blue color, antipyrin under- going no change with silver nitrate. From acetphenetidin or acetanilid it is easy to distinguish antipyrin, because neither is easily dissolved in cold water, and neither gives a pre- cipitate with potassium mercuric iodide, and on hydrolysis with dilute acid acetphenetidin yields a solution which on dilution gives a blue color with bromide bromate reagent, and acetanilid yields anilin and acetic acid, and furthermore gives the carbylamin reaction. COMPARATIVE REACTIONS OF ANTIPYRIN, PYRAMIDON AND TOLYLPYRIN Antipyrin Pyramidon Tolylpyrin Melting-point 113-114 when anhy- drous 108° 136-137° Ferric chloride Red-brown Blue by reflected, violet by trans- mitted light Violet Silver nitrate No change Blue silver deposit No change Nitrous acid Bright green Blue to violet Green Nitric acid Deep red No red Cherry red Iodin solution Brown red precipi- Violet coloration ; Red-brown precipi- tate disappears on excess of reagent tate which d i s- heating gives a turbidity which dissolves on warming solves on heating Bromin water White precipitate Concentrated solu- tion gives a black or gray color In making quantitative estimations of antipyrin, the first step con- sists in separating it from the body of the product. This may be accom- SYNTHETIC ORGANIC NITROGEN COMPOUNDS 795 plished by treating the solution with a slight excess of sodium hydroxide and extracting three times with chloroform. If the specimen under examination is a pill or tablet in which antipyrin occurs by itself or with bromides, an aqueous solution may be rendered alkaline and shaken out with chloroform and on filtering, carefully evaporating the solvent in a tared dish and drying over sulphuric acid the antipyrin will be pure enough to weigh. If it is desired to check the figure by a volumetric estimation the following method may be employed : To a concentrated aqueous solution of the antipyrin a slight excess of iodin solution (100 mils N/20 iodin containing 10 to 20 grams potas- sium iodide per liter and 4 mils hydroidic acid sp. gr. 1.7) is added and the flask well shaken until the precipitate adheres to the walls and the liquid becomes clear. The liquid is then filtered through a small asbestos filter and the residual iodin determined in an aliquot by titration with thio- sulphate, 21.3 mils N/20 iodin = 0.1 gram antipyrin. Lemaire 1 has suggested a volumetric method depending on the pre- cipitation of the antipyrin by picric acid and titrating the excess of acid with sodium hydroxide. This procedure is of especial value when it is desired to estimate antipyrin alone or in the presence of caffein, as the latter has no influence. ASSAY OF LIQUID HEADACHE MIXTURES Method Involving the Precipitation of Antipyrin with Mercuric Nitrate and Purification of Caffein. — Measure 25 mils of the sample accurately with a standardized pipette or measuring flask, washing out the graduate and introducing into a 16 oz. separatory funnel (Squibb type). Add a slight excess of 10 per cent sodium hydroxide, shake out with four 50-mil portions of chloroform. Each shake-out should consume at least five minutes and the separator be allowed to stand for about five minutes after each shake-out in order that the solvent may completely separate. Run off the chloroform from each extraction into another separator, and when the four shake-outs have been united, run into a flask of about 300 mih capacity and recover the bulk of the chloroform, which can be used over again for subsequent extractions. Finally, run the residual chloroform into a tared beaker or dish, wash out the flask with a little pure chloroform, evaporate over a steam- or water-bath, using a fan or air pressure to hasten the volatilization of the solvent; dry the residue for about an hour at a temperature of 100° and weigh. Dissolve the residue in the beaker in about 25 mils of water. Pour the mixture into a 100-mil graduated flask, wash out the beaker with a little water and ad&an excess of mercuric nitrate solution (1 : 3). This is best accom- h 1 Pharm. J., 1905, 74, 13. 796 ORGANIC SUBSTANCES plished by adding the reagent in small quantities at a time, allowing the precipitate to settle and observing when no further addition of the reagent produces a precipitate. Then make up to the mark with distilled water and shake thoroughly. When the precipitate has settled, filter off one- half of the liquid in a flask, amounting to 50 mils and shake out four times with 50-mil portions of chloroform. Unite the chloroform extractions, add 10 mils of dilute ammonia water, and shake throughly. Run the chloroform into another separator and shake out with water; then run the chloroform into a flask, recovering the greater portion as above, and then evaporate the remainder in the same flask, over a steam-bath, using a current of air to hasten the evaporation. When all the chloroform has been driven off, add 15 mils of dilute hydrochloric acid and 15 mils of iodin solution (10 mils of iodin — 20 mils of potassium iodide — 100 mils water). Allow this to stand overnight, tightly corked. Filter onto a dry filter and wash twice with about 10 mils of iodin solution. Then transfer the filter containing the precipitate back into the flask in which the precipitation was made; add 15 mils of water and about one-third of a gram of sodium sulphite and a drop of dilute sulphuric acid. Warm, and as soon as the precipitate has dissolved and there is no further color of the iodin left, filter into a separator, neutralize with ammonia, and shake out five times with chloroform, using the following amounts: 25 —15— 15— 10— 10 mils. Unite the chloroform extractions, insert a pledget of cotton into the stem of the separator which has been previously dried with a piece of filter paper, run the chloroform through the stem into a tared dish, washing out the inside of the separator once with about 5 mils more chloroform, evaporate the solvent, and weigh the residue as caffein. This weight multiplied by 2 and subtracted from the total weight of the mixture of antipyrin and caffein will give the weight of the antipyrin. By multi- plying this figure by 1.18, the amount of antipyrin in one fluid ounce of the mixture will be obtained, and referring to a comparative table the amount in grains may be read off. Method Involving the Precipitation of Antipyrin with Picric Acid and Titrating the Excess of the Reagent. — Measure out a 25-mil sample of the product as described in the previous method, transfer to a separator, add an excess of sodium hydroxide, shake out four times with 50-mil portions of chloroform, unite all the chloroform extractions obtained, wash with about 10 mils of water, and then run the chloroform through a pledget of cotton into a flask for recovery. Recover the bulk of the solvent and finally evaporate the balance over a steam-bath and leave the residue in the flask in which the distillation was made. After the solvent has been entirely driven off, add about 10 mils of water and warm. Transfer the aqueous liquid to a 50-mil graduated flask, washing out the SYNTHETIC ORGANIC NITROGEN COMPOUNDS 797 distilling flask with a little water to make sure that all of the antipyrin and caffein is removed, and finally make up to the mark with distilled water. Shake thoroughly, remove 10 mils with a pipette, and transfer to a small flask. Add from a burette exactly 40 mils of N/20 picric acid ; shaking as the addition is made. Allow the solution to stand for about an hour, then filter off through a dry filter exactly 25 mils, using a gradu- ated flask to obtain the proper quantity. Transfer the aliquot to a flask of about 100 mils capacity, washing out the graduate and adding about 25 mils of water. Add two or three drops of phenolphthalein and titrate with an exactly N/10 solution of sodium hydroxide. The end-point is reached when one drop of the acid produces a color which does not fade and which resembles in shade the color of the solution of acid bichromate of potassium. A blank must be run on 40 mils of the picric acid solution used. The calculation is as follows : Multiply the number of mils of N/10 alkali required to titrate the excess of picric acid by 4 and subtract this figure from the number of mils of N/10 alkali required to neutralize the 40 mils of picric acid. Multiply this figure by .009338 and the product by 5. which will give the amount of antipyrin in the 25-mil sample taken. It is not necessary to have an exact known solution of picric acid, but it should be made approximately N/20, as a solution of stronger con- centration cannot be obtained, and if a blank is run, its equivalent in terms of N/20 picric acid is easily obtained. Emery recommends the following methods for determining anti- pyrin and the ingredients accompanying it in various combinations. Method of Analysis of Headache Mixtures Containing Antipyrin, Acetphenetidin, and Codein Sulphate. — Antipyrin may be estimated gravimetrically as in the case of caffein, or volumetrically by means of a standard alcoholic solution of iodin in the presence of mercuric chloride. Its separation from acetphenetidin or acetanilid is easily effected by means of chloroform, after subjecting a mixture to hot digestion with dilute sulphuric acid, whereby the arlyamids are changed into the cor- responding sulphates. Ascertain the weight of 20 tablets, then weigh out an amount of the finely powdered sample equal to the average weight of one tablet, transfer to a separatory funnel, add 50 mils of chloroform, 10 mils of water, and a few drops of dilute sulphuric acid. Shake vigorously, allow to clear, then draw off through a pledget of cotton and a small dry filter into a 200- mil Erlenmeyer. Repeat the extraction four times, distilling off a por- tion of the solvent on completion of the third shake-out, in order to accom- modate the chloroform from the final two extractions in the same flask. On completion of the fifth and final shake-out, distill the chloroform down 798 ORGANIC SUBSTANCES to about 10 mils add 10 mils of dilute sulphuric acid (1 : 10 by volume), continue heating gently until all the solvent has passed over, remove to steam-bath, and digest till the volume of liquid amounts to about 5 mils, add 10 mils of water, and continue the treatment until the liquid is again reduced to 5 mils 1 . In order that the hydrolysis may be complete, that is, no particles of acetphenetidin remain on the sides of the flask, rotate the latter gently from time to time during the process of digestion, or better, perhaps, add a few drops of alcohol or chloroform now and then. Antipyrin. — Transfer the aqueous acid solution of phenetidin sul- phate and unchanged antipyrin to a separatory funnel by the aid of water, so that the final volume does not exceed 20 mils. Make seven extractions with 30-mil portions of chloroform, clearing and drying the solvent by means of a cotton pledget and dry filter as hereinbefore de- scribed. Distill the united chloroformic extractions down to about 10 mils, transfer to a tared 50-mil beaker, evaporate on a steam-bath to apparent dryness; cool, and weigh. It has been found that antipyrin retains traces of moisture and chloroform with great obstinacy, hence several days are required, even with the help of a vacuum desiccator, to approximate to a constant weight. It is therefore more expeditious to subject the crude residue to volumetric estimation. To this end dis- solve the antipyrin in 95 per cent alcohol, transfer to a 100-mil graduated flask, and fill to the mark. Titrate an aliquot (20 mils or more if the amount of antipyrin is relatively small) of the alcoholic solution of anti- pyrin thus prepared with an iodin solution prepared and standardized in the following manner: Make up three solutions — A, containing 1.351 grams of resublimed iodin in 100 mils of 95 per cent alcohol; B, contain- ing 1 gram pure antipyrin in 100 mils of 95 per cent alcohol; C, contain- ing 5 grams of mercuric chloride in 100 mils of 95 per cent alcohol. Into a 100-mil Erlenmeyer measure from a burette 20 mils of Solution B, and by means of a pipette 10 mils of Solution C, then run in from a burette the iodin solution until a faint yellow coloration persists after a lapse of three to five minutes. Run several duplicates and it will be found that, under the conditions obtaining in the experiment, approximately 20 mils of the iodin solution thus standardized will very nearly correspond to 1 mil of antipyrin solution, or, by weight, 10 mg. of antipyrin. The value of the iodin solution in terms of antipyrin having been thus deter- mined, subject the aliquot of the alcoholic solution of antipyrin from sample under examination to a similar treatment, basing the final result on an average of two or more titrations. Since the presence of either acetphenetidin or codein is apparently no bar to the accuracy of the above reaction, it is wise to check the value for antipyrin already obtained by treating the original sample as follows: Weigh out on a small (5.5 cm.) filter an amount of the powdered sample SYNTHETIC ORGANIC NITROGEN COMPOUNDS 799 equal to the average weight of one tablet, wash with successive small portions of 95 per cent alcohol, in quantity about 20 to 30 mils, sufficient at least to remove all the antipyrin in the mixture. Collect solvent in a 100-mil Erlenmeyer, add 10 mils of solution C, then run in the standard iodin until a faint yellow coloration persists. The number of cubic centi- meters of iodin required to effect this should agree approximately with the value previously obtained. Acetphenetidin. — Wash the filter used to dry the chloroform solution of antipyrin once with 5 mils of water, allowing the latter to run into the separator containing the phenetidin sulphate. Treat the solution with successive small portions of solid sodium bicarbonate until an excess of this reagent, after complete neutralization of the sulphuric acid, per- sists at bottom of the liquid. Now add 60 mils of chloroform and, for every 100 mg. of acetphenetidin known or believed to be present, about 5 drops acetic anhydride; shake for some time vigorously, allow solvent to clear, then pass through cotton, and dry filter into a 200-mil Erlen- meyer, exactly as in the extraction of caffein. Distill over 50 mils of the chloroform, make up to 60 mils with fresh solvent, and extract again. Draw off chloroform, distill as before, this time about 60 mils, then make a third and final extraction. Distill to about 10 mils, transfer by pouring and rinsing with small quantities of chloroform to a tared 50-mil crys- tallizing dish, evaporate on the steam-bath to apparent dryness, finally removing any considerable excess of acetic anhydride by repeated addi- tions of about 1 mil of fresh chloroform, containing 1 to 2 drops alcohol. The acetphenetidin should finally appear as a whitish, crystalline mass, having usually a faint acetous odor. This will entirely disappear on standing some time in the open, or more quickly in a vacuum desiccator over lime. The residue should be repeatedly weighed until it suffers no further loss. Codein Sulphate. — The estimation of codein can be carried out during the hydrolysis of acetphenetidin. Wash the filter used to dry the chloro- form solution of antipyrin and acetphenetidin once with 5 mils of water, receiving latter in the separator containing the aqueous-acid solution of codein. Add solid sodium bicarbonate in slight excess, then extract three times with 50 mils of chloroform. Clear, dry, and collect solvent from the three operations in a 200-mil Erlenmeyer, then distill down to 10 mils. Transfer to a 50-mil tared beaker, evaporate to apparent dryness on the steam-bath, moisten the amorphous residue with a few drops of alcohol, evaporate again, cool, and weigh. This weight, multiplied by the factor 1.3144, will give the amount of codein sulphate originally present in the sample. It is recommended that this result, which is likely to be somewhat high, be verified by titrating the crude codein with N/50 sul- phuric acid, using 1 drop of methyl red solution as indicator. 800 ORGANIC SUBSTANCES In the event that acetanilicl instead of acetphenetidin is employed in combination with antipyrin and codein sulphate, it would be necessary to modify the procedure only as regards the final treatment of the aqueous acid solution containing in addition to antipyrin the acetanilid, which after being subject to hydrolysis and freed from the former is titrated with potassium bromide-bromate. ESTIMATION AND SEPARATION OF ANTIPYRIN FROM VARIOUS SYN- THETIC PRODUCTS BY MEANS OF ITS PERIODIDE. 1 Direct estimation when no other substance is present which will itself or after treatment with iodin be extracted by chloroform. Method I. — Aqueous solution of the antipyrin (containing not over .25 gram antipyrin in 10 mils water) is poured into a large separatory funnel, 20 mils saturated sodiun bicarbonate solution is added, a few mils of washed chloroform (to remove alcohol), 100 mils water and about 50 mils of approximate N/10 iodin is added. The solution is shaken thoroughly about six times at intervals. The excess of iodin is removed by adding a few mils of sodium thiosulphate and shaking. The resulting iodoantipyrin is shaken out with three 30-mil portions of chloroform and washing each extract with about 10 mils water in a small separa- tory funnel and filtering through cotton into a tared 150-mil Erlenmeyer to a condenser, and chloroform distilled down to recover most of the the chloroform, until about 10 mils remain. This is then evaporated to dry- ness on the water-bath (preferably over a blast) and dried in oven at 110° C. for half hour. Multiply the iodoantipyrin by factor .5992 (H = l) to antipyrin. DETERMINATION OF ANTIPYRIN. SEPARATION BY PERIODIDE METHOD FROM ACETANILID, SULPHONAL, AND PHENACETIN Method II. — To an aqueous solution of antipyrin (not over .25 gram in about 50 mils water) in a 500-mil Erlenmeyer flask, add 20 mils strong hydrochloric acid, about 100 mils of approximate N/10 Iodin in potas- sium iodide, shake well and allow tarry precipitate to settle clear (should be allowed to stand at least three hours). Ten mils hydrochloric acid is sufficient if allowed to stand overnight. Pour off the clear supernatant liquid through a funnel plugged and overlaid with glass wool and a little asbestos. Wash the tar by decantation about eight or nine times with about 20 mils acid water (5 per cent HC1 solution) each time keeping as much of the tar in the flask as possible. Then place the funnel contain- ing some of the tarry precipitate in a large separatory funnel, dissolve 1 W. O. Emery and S. Palkin. J. Ind. & Eng. Chem., 1914, 6, 751. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 801 the tar in the Erlenmeyer by warming slightly with about 50 mils of methyl alcohol (free from ethyl alcohol and acetone) making sure that all the tar is in solution, pour through funnel into the separatory funnel, thus dissolving the tar left on the glass wool. Wash Erlenmeyer and funnel several times with methyl alcohol from a wash bottle until every- thing (all the tar) has been washed in the separatory funnel. Add 30 mils saturated sodium bicarbonate solution, dilute with about 50 mils water, shake thoroughly three to four times at intervals, allowing to stand a few minutes each time. Remove the excess of iodin with a few mils of strong sodium thiosulphate solution, now shake out the resulting iodo- antipyrin with 40 mils chloroform, draw off the chloroform extract into a small separatory funnel and wash with about 10 mils water, and filter through cotton into a tared 150-mil Erlenmeyer. Repeat this operation twice with 40 mils chloroform each time, using the same wash water, (three times in all). Distill the chloroform extracts to recover most of chloroform as described in method I, and finally evaporated to dryness on steam-bath, dry in oven at 110° for half -hour and weigh the iodoanti- pyrin. Multiply the iodoantipyrin by the factor .5992 (H = l) to obtain tne amount of antipyrin. ASSAY OF TABLETS CONTAINING CAFFEIN AND ANTIPYRIN IN ADMIXTURE Method. — Weigh out on a metal scoop or watch-glass 0.25 gram of the sample, transfer to a 150-mil separatory funnel with 5 mils alcohol- free chloroform and 10 mils water, add 0.5 gram sodium bicarbonate and about 10 mils N/5 iodin (or double the quantity of N/10 iodin), then shake vigorously one minute, after which operation a slight excess of iodin should still be apparent in the liquid menstruum, provided all the antipyrin has been converted to iodoantipyrin. If, however, all the iodin has been thus expended, a little more should be added and the mix- ture again shaken. Now discharge the uncombined iodin by means of a small crystal of sodium thio sulphate, add 20 mils U. S. P. chloroform and shake. After clearing, draw off solvent into a second separator containing 5 mils water, shake, and after clearing pass the chloroform through a small dry filter into a tared 50-mil beaker, evaporate to apparent dryness on the steam-bath, accelerating this operation by means of an air blast, if available. Repeat extraction with two (three, in case N/10 iodin were used) 25-mil portions of chloroform, washing, filtering, and evaporating each portion in rotation substantially as directed for the first portion. Recover all traces of crystalline products separating about tips of funnels and edge of filter by judicious washing with chloroform. 802 ORGANIC SUBSTANCES The final colorless, crystalline residue of caffein and iodoantipyrin is dried one-half hour at 100°, then cool, and weigh. Designate this weight A. Dissolve this residue in 5 mils glacial acetic acid, add 10 mils saturated aqueous solution sulphur dioxide, then transfer the resultant liquid by pouring and rinsing with hot water to a 400-500 mil beaker, until the final volume amounts to about 200 mils. Add aqueous silver nitrate solu- tion (containing about 0.25 gram silver nitrate) and follow with a few drops of nitric acid, then heat nearly to boiling, stirring the while in order to agglomerate the silver iodide. Add about 15 mils cone, nitric acid, cover beaker with watch-glass and boil gently five minutes. Filter by decantation through a tared Gooch, wash precipitate twice with boiling water, finally transferring the silver iodide completely to the Gooch, washing several times with hot water and finally with alcohol. Dry one-half hour in air bath at 110°, cool, and weigh. The weight of silver iodide multiplied by the factor 0.8012 yields the quantity of antipyrin present in sample taken. The quantity of caffein present in sample is ascertained by subtracting the product, obtained by multiplying the weight of silver iodide by the factor 1.3374, from the weight designated A. ASSAY OF LIQUID HEADACHE MIXTURE CONTAINING ANTIPYRIN AND CAFFEIN Method. — By means of a pipette standardized at 20°, transfer 10 mils of the solution, previously warmed or adjusted to 25°, to a 150-mil sepa- rator^ funnel containing 0.5 gram sodium bicarbonate. Add about 15 mils N/5 iodin (or double the quantity of N/10 iodin), then shake vigor- ously one minute. All succeeding operations are identical with those outlined for the powder mixture. Comments and Suggestions. — The foregoing procedure is based on the fact that, when an aqueous solution of iodin and sodium bicarbonate is permitted to react with antipyrin, whether alone or with other sub- stances as caffein, mono -iodoantipyrin is formed. This latter substance, together with caffein, is thereupon extracted with chloroform, the weight of such mixture ascertained and the iodin therein estimated as silver iodide, from which the antipyrin is calculated by means of the appro- priate factor. In view of the somewhat radical treatment with dilute nitric acid, to which the caffein is necessarily subjected incidental to the precipitation of silver iodide, a direct determination of that substance is impracticable. The quantity of caffein is, however, ascertained by subtracting the amount of iodoantipyrin, as calculated from the silver iodide, from the combined weight of caffein and iodoantipyrin. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 803 The use of alcohol-free chloroform is specified in order to preclude the possible formation of iodoform, the presence of which would necessarily render the method valueless. The final washing of the silver iodide with alcohol should be thorough in order to eliminate certain unidentified organic substances arising from the action of nitric acid on the antipyrin complex. There are several antipyrin compounds used medicinally. Antipyrin Salicylate, CnH^NaOCeB^OHCOOH is a weak chemical combination of antipyrin and salicylic acid. It occurs as a white, coarsely crystalline powder, or in hexagonal tabular crystals, melting at 71 to 92° C, odorless, slightly sweet, soluble in alcohol, less readily in ether. It is decomposed by acids with the elimination of salicylic acid, and by alkalies with the elimination of anti- pyrin. Its aqueous solution is rendered milky by tannic acid, then colored green by the addition of a few drops of fuming nitric acid. It is colored deep red by ferric chloride, passing to violet red on copious dilution with water. Tussol— Antipyrin Mandelate, CnHi 2 N 2 • C 6 H 6 • CHOH • CO OH, a salt of mandelic acid, CeHoCHOH • COOH, and antipyrin. It is a white crystalline powder, having a bitter taste and melting at 52 to 53° C. It is soluble in 15 parts of water, 3 to 4 parts of alcohol, or 25 to 26 parts of ether, producing solutions of acid reaction. When heated above the melting-point, it gives off the odor of bitter almonds, and finally burns without leaving a residue. It is split into its constituents by milk and by alkalies. Its aqueous solutions give the reactions for antipyrin ; if warmed with potassium permanganate it develops the odor of benzaldehyde, but is not effected by silver nitrate, barium nitrate, dilute sulphuric acid, or hydrogen sulphide; useful in the treatment of whooping-cough. FERROPYRIN, (C u H 12 N 2 0) 3 (FeCl 3 ) 2 Ferropyrin is a compound of antipyrin and ferric chloride, containing about 35 per cent of ferric chloride and 64 per cent of antipyrin. It is a yellowish red, crystalline powder, having an acid-astringent taste. It is soluble in 5 parts of cold water, but requires 9 parts of hot water for solution; it is soluble in alcohol, but insoluble in ether. It should form a clear blood-red solution in water. Its aqueous solu- tion 1 : 5 yields a precipitate of ferric hydroxide on addition of ammonia 804 ORGANIC SUBSTANCES in excess, and the nitrate should give no reaction for nitric or sulphuric acid, nor heavy metals, and should yield a residue on evaporation, which is completely volatilized when heated on platinum. After acidification with nitric acid, the filtrate yields a white precipitate with silver nitrate and in the filtrate from this the antipyrin may be detected by means of ferric chloride or by nitrous acid. It is hematinic, hemostatic, astringent, analgesic, and tonic. Antipyrin Iodide — Iodopyrin The compounds of iodin and antipyrin have been studied by Emery as noted under the methods for the quantitative determination of the base. One of these which is claimed to contain but one atom of iodin is used to a limited extent as an antipyretic, alterative, and analgesic in tuberculosis, syphilis, typhoid fever, bronchitis, and asthma. Antipyrin Monobromide A compound analogous to the one previously mentioned, but contain- ing bromin instead of iodin, is called bromopyrin, and is used as an antipyretic and antiseptic. It melts 114° C. The name a Bromopyrin " is applied to mixtures of the general type of caffein, antipyrin, and alkali bromides. Methylenediantipyrin — Fermopyrin This product results from heating together antipyrin and formal- dehyde. Methylenediantipyrin tetrabromid, salubrol, has been described under formaldehyde. Salubrol is an orange-yellow powder, melting 155° and used as a substitute for iodoform. Antipyrin Salicylacetate There seem to be two products bearing this name, one of which is a salt of acetylsalicylic acid and the other a somewhat uncertain mixture. They combine the virtues of antipyrin and salicylic acid, and are hence used in rheumatic condition where an analgesic is required. The salt of acetylsalicylic acid is also called acetopyrin and acopyrin, and the other product pyrosal. Antipyrin Resorcylate — Resalgin Resalgin or resorcylalgin purports to be a salt of betaresorcylic acid and forms colorless needles melting 115° C. It is used as an antiseptic. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 805 Resopyrin Resopyrin differs from resalgin in that it is a product resulting from the fusion of molecular proportions of resorcin and the base. It is another of those compounds where chemical individuality is a matter of doubt. Chloral hydrate and antipyrin combined are called Hypnal, and the crystalline product melts at 67° and is used in cases of insomnia and spas- modic cough. It reduces Fehling's solution, gives a blood-red color with ferric chloride and chloroform on boiling with alcoholic potash. Antipyrin and paramidobenzenesulphonate produce sulphopyrin, and a mixture of carbolic acid and the base is called Phenopyrin. It will be noted from a survey of the above products that while there are a few well-defined salts of antipyrin, the majority of the compounds are of a more or less doubtful nature. Antipyrin is not a strong base chemically and hence a hard and fast union with the weak acids and phenols is not to be expected. While it is not questioned that an equmbrium of greater or less stability may be obtained as the result of a fusion, the ease with which the compounds are separated and identified when sub- jected to the simple action of water is sufficient to show that no very permanent compound has been formed. Paratolyldimethylpyrazole Tolylantipyrin is prepared by treating paratolylhydrazine with aceto- acetic ester and methylating the resulting product. .CO— CH CH3C 6 H4N< || X -N— C— CH 3 I CH3 It is a colorless crystalline substance with a bitter taste and melts /JJ&-137 . It resembles antipyrin in its physiological properties, and might at first be mistaken for it, but the difference in its chemical character- istic will be noted in the table of comparative reactions on page 794. The salicylate of this base is called Tolysal. It is analogous to anti- pyrin salicylate, and is used as an antineuralgic and antirheumatic. Thioantipyrin CH 3 I C=N — CH3 S<^)N— C 6 H 5 HC=C Melts 166°. It gives a transient green color with ferric chloride, but not with nitrous acid. 806 ORGANIC SUBSTANCES Selenopyrin melts 168°. It gives no color with ferric chloride and only a faint green with nitrous acid. Melubrin Melubrin is sodium l-phenyl-2, 3-dimethyl-5-pyrazolon-4-amido- methan-sulphonate, ,CO C • NH ■ CH 2 • S0 3 Na ^NCCHa)— CCCHs) c 6 h 5 n/ the sodium salt of l-phenyl-2, 3-dimethyl-5-pyrazolon-4-amido-methan- sulphonic acid, differing from antipyrin in that a sodium-amido-methan- sulphonate group, • NH • CEbSOsNa, has replaced a hydrogen atom of the pyrazolon group. It is a white, odorless, almost tasteless crystalline powder, readily soluble in water, but slightly soluble in alcohol. The aqueous solution is neutral in reaction but unstable. If about 0.2 gram of melubrin dissolved in 5 mils of water is boiled with 3 mils of diluted hydrochloric acid, sulphur dioxide and formaldehyde will be liberated. If one-half of the solution thus formed is treated with 3 drops of sodium nitrite solution and 5 mils of an alkaline solution of betanaphthol, a red precipitate will be produced. If the remainder of the above solution is treated with 1 gram of sodium acetate and 15 mils of a saturated aqueous benzaldehyde solution, a yellowish-white, flocculent precipitate will be formed which, when washed and dried, will melt at 173°. If 0.4 to 0.5 gram of melubrin is weighed into a platinum dish, treated with dilute sulphuric acid, and heated to constant weight, the sodium sulphate thus formed should weigh 0.2160 to 0.2250 gram for each gram of material used, representing a sodium content of 6.99 to 7.28 per cent. It is used as a antipyretic in fever and is analgesic, Iodomethyl Phenylpyrazolon A substance claiming to be an iodin derivative of this character is sold under the name of Mydrol. It is soluble in water and alcohol and is used as a mydriatic. Pyramidon ' The use of pyramidon in medicine is probably on the increase, and the analyst may encounter it in any new mixture intended for antipyretic purposes. Especial note is made of this because a worker experienced SYNTHETIC ORGANIC NITROGEN COMPOUNDS 807 in the analysis of medicines knows that there are practically only three antipyretics in general use and that the extent of their prevalence is in the following order, acetanilid, acetphenetidin, and antipyrin. Pyramidon is phenyl-dimethyl-dimethylamino-pyrazolon, C 6 H5N<^ CO C-N(CH3) 2 II N(CH3)-C(CH 3 ) differing from antipyrin in that a dimethylamino group, N(CHs)2, has replaced a hydrogen atom of the pyrazolon nucleus. It is prepared by the reduction of nitroso-antipyrin to amidoanti- pyrin and treating this with methyl chloride or iodide. It forms small, colorless, slightly alkaline crystals, melting at 108° C; almost tasteless; soluble in 11 parts of cold water and readily soluble in alcohol, ether, and benzene. Its aqueous solution saturated at 70° C. deposits oily globules of pyramidon on boiling. Ferric chloride colors the neutral or slightly acidulated solution of pyramidon a bluish-violet color; nitrous or nitric acid produces a fugitive blue-violet color; silver nitrate produces an intense violet coloration when added to the aqueous solution, followed by the formation of a black pre- cipitate of metallic silver, and the same color is produced by platinum chloride, by ammonium persulphate, and by lead dioxide. In hydro- chloric acid solution pyramidon gives a fine crystalline double salt with mercuric chloride. Pyramidon may be estimated by means of picric acid by the same process as antipyrin. Pyramidon Acid Camphorate, C13H17N3O • CioH 16 04 is an acid salt of pyramidon and camphoric acid. It is a white, crystal- line powder of acid reaction, melting (indefinitely) at 84 to 94° C, soluble in 20 parts of water or 4 parts of alcohol. It gives the characteristic reaction of pyramidon with silver nitrate. If the solution in hot water is made alkaline with caustic soda, the pyrami- don may be shaken out with chloroform; if the residual aqueous liquid is then acidified with sulphuric acid the camphoric acid (melting-point 186° C.) may be shaken out with ether. Pyramidon Neutral Camphorate, (CiaHtfN-sO^-CioHieO* is a neutral salt of pyramidon and camphoric acid. It is a white, crystal- line powder, melting (indefinitely) at 80 to 90° C. It dissolves with acid reaction in 15 parts of water or 2 parts of alcohol. 808 ORGANIC SUBSTANCES Pyramidon Salicylate, C13H17N3O • CyHeOa is a salt of pyramidon and salicylic acid. It is a white, crystalline powder, having an acid reaction and melting indefinitely at 68 to 70° C. It is soluble in 16 parts of water or 5 to 6 parts of alcohol. The aqueous solution is colored intensely red by ferric chloride, and produces a white precipitate with silver nitrate, the solution assuming a violet color after a short time. Trigemin Trigemin is prepared by combining butylchloralhydrate and pyrami- don, and is used as an analgesic and sedative. It is soluble in water and other ordinary organic solvents except petroleum ether, which has but slight action, and melts 83-85°. Arhovin, Ci Hi 3 • C 6 H4(COOC 2 H 5 ) (C 6 H 5 ) 2 NH Arhovin is an addition product of diphenylamine and thymylbenzoic acid. It is an oily liquid, with an aromatic odor and a cooling and after- ward burning taste. It is insoluble in water, but dissolves in alcohol, ether, chloroform, and oily liquids and is employed as an antiseptic in venereal troubles. * Agathin— Salicylalphamethyl Phenylhydrazone, C 6 H5-N(CH 3 )N : CH CeHiOH Agathin is a reaction product of alphamethyl phenylhydrazine and salicylic aldehyde. It forms yellowish crystals melting 74° C, soluble in alcohol, ether, and benzol, but insoluble in water. It is used as an antirheumatic and antineuralgic. DIAMINES The diamines are derived from a double molecule of ammonia by the replacement of two or more of the hydrogen atoms by hydrocarbons of the olefine, phenylene, or naphthalene series. Ethylene-diamine, NH 2 CH 2 • CH 2 NH 2 Ethylene-diamine is formed by the reaction of ethylene chloride or bromide and alcoholic ammonia at 100-120° C. It is a viscous volatile liquid, with a slight ammoniacal odor, sp. gr. .902 at 15° C, boiling 117°, easily soluble in water but insoluble in ether. It dissolves albumen and fibin, and is employed in medicine as an adjuvant to the treatment of diphtheria. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 809 It forms with mercuric sulphate a white crystalline substance known as sublamine, which is soluble in water and glycerin and is used instead of mercuric chloride in syphilis, gynecological practice, and as a vaginal douche. A solution of silver phosphate in an aqueous solution of ethylene- diamine is called Argentamine, and is used as an antiseptic or astringent in gynecological and ophthalmic practice. An aqueous solution containing 25 per cent ethylene diamine and 25 per cent cresol is used as a bactericide. Kresamine is a product of this type. Diethylene-diamine — Piperazine, C4H10N2 Piperazine is a well-defined base having the composition H I N HsC./NcHa H 2 cl J-CH 2 N I H It forms colorless, lustrous, tabular crystals, hygroscopic, which melt at 44° C. (104-107° when anhydrous and boils at 145°). It is extremely soluble in water, forming strongly alkaline but non-caustic solutions, which dissolve carbon dioxide. It is not so readily soluble in alcohol. It is volatile. It forms soluble salts with acids, and with uric acid it forms a very soluble salt (in 50 parts of water; lithium urate requires 368 parts of water) . It is not affected by chromic acid, but is slowly oxidized by potassium permanganate. In aqueous solution it gives a characteristic scarlet-red precipitate" with potassium-bismuth iodide, a white precipitate with Nessler's reagent, and is precipitated light blue by copper sulphate, white by mercuric chloride, lemon yellow (crystalline) by picric acid and grayish by tannic acid. Piperazine forms a series of rrydrates containing from one to six mole- cules of water, the latter being the most readily obtained. The picrate is very insoluble in water and is obtained by simply add- ing an excess of a solution of the reagent. The reaction may be used as a means of estimating piperazine, and the details are the same as for determination of antipyrin by the same reagent. 810 ORGANIC SUBSTANCES When sodium nitrite is added to a solution of piperazine in dilute hydrochloric acid, and the mixture warmed, a dinitrosopiperazine sepa- rates which, on recrystallization from boiling water, forms yellowish plates melting 158°. It gives a deep blue color after some minutes with a solu- tion of phenol in sulphuric acid. Piperazine is used in gout, for the relief of irritation of the bladder, rheumatism, renal colic, and for the prevention of the formation of renal and vesical calculi. Sidonal — Piperazine Quinate •CH2CH 2 \ NH< >NH • 2C 6 H 7 (OH) 4 (COOH) ^CH 2 CH 2 ' the normal salt of piperazine and quinic acid. It forms a white, crystalline powder, melting at 168 to 171° C, and having a faint acid taste and reaction. It is very soluble in water and forms salts on mixing the aqueous solutions with solution of alkali car- bonates and evaporating to dryness. It responds to tests for piperazine (precipitate with potassium-bismuth iodide, etc.) and quinic acid. Sidonal is used as a uric acid solvent in gout, neurasthenia, etc. Dimethyl Piperazine— Lupetazin, NH^Hs-CHs^NH Lupetazin is a colorless oily liquid boiling 153-158°, the base of lycetol. It gives precipitates with iodin, picric acid, and bromin water, but not with Mayer's reagent. Lycetol — Dimethyl Piperazine Tartrate NH+H 2 C4H406 CH 2 CH(CH 3 ) ' It is a white, odorless powder, melting at 250° C, anhydrous, but slightly hygroscopic. It is soluble in water, forming agreeably acidulous solutions. Ethylene-ethenyl-diamine — Lysidine Lysidine is an hygroscopic, reddish-white crystalline substance with a peculiar odor resembling coniin and having the composition CH 2 NH X I >C-CH 3 . CH 2 — N^ It dissolves easily in water and is used for the same purposes as piperazine. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 811 It melts 100-106°, very soluble in alcohol, somewhat in chloroform, but insoluble in ether. It gives precipitates with the general reagents for alkaloids, and forms a soluble urate. Naphthylamines, Ci H 7 NH 2 Naphthylamine occurs in two forms, the alpha and beta. i i i U\> TH2 x/V NH 2 The alpha melts 30°, boils 300° C, soluble in alcohol and ether. The beta melts 112°, boils 294° C, soluble in alcohol, ether, slightly in water. Thermin — Tetrahydrobetanaphthylamine Hydrochloride, CioH n NH 2 • HC1 Thermin forms colorless to reddish-white crystals, melting 237° C, soluble in water and alcohol. It is used as a mydriatic, and to increase the bodily temperature. Pyridin The nitrogenous bodies with the nitrogen atom in a closed complex are usually derivatives of pyridin, quinolin, or acridin. The plant alkaloids are generally derivatives of the first two. Pyridin, C5H5N, occurs in bone oil or coal tar. When pure it is a colorless,- mobile liquid with a pungent characteristic odor, boiling 115° and miscible with water in all proportions. It is a strong base, turning red litmus blue and combining with acids to form crystalline salts. The platinochloride crystallizes in orange-yellow needles readily soluble in water, but on boiling, a very sparingly soluble j r ellow salt separates. If pyridin or its homologues are treated with methyl iodide, a methiodide is produced, and if this is then subjected to the action of heat in presence of potassium hydroxide a very pungent and disagreeable odor is evolved. It does not give the carbylamine reaction nor does it react with nitrous acid. Pyridin has the structure H C Hc/N^H Hcl ,CH N 812 ORGANIC SUBSTANCES It is unsaturated, but the positions of unsaturation are not as yet satis- factorily established. Piperidin obtained by boiling piperin with alkalies,' is hexahydro- pyridin H 2 C H 2 (X ^CHa H 2 Cv /Cr±2 N a colorless liquid boiling 106° with a penetrating odor like pepper. Pyrrole CH=CH NH CH=CH Pyrrole and two isomeric methyl pyrroles, are associates of the pyridin bases in coal tar and bone oil. Pyrrole is a colorless pungent-tasting liquid with a chloroform-like odor, sp. gr. .9669 at 20°, boiling 130-131°. It is a weak base, dissolving in acids, and is indifferent to .alkalies. It is soluble in alcohol and ether, but almost insoluble in water. It forms an unstable red picrate, melting 71°, and a grayish-brown tetraiodo com- pound melting between 140-150°. Pyrrole turns brown on exposure to the air. Heating with acid gives pyrrole red, and its vapor reddens a piece of pine wood moistened with hydrochloric acid. A solution of alloxan on boiling with a small quantity of pyrrole turns blue, changing to red on cooling, and to green and blue on addition of alkali. If pyrrole is added to a weak solution of isatin in water, acidulated with sulphuric acid and cooled to 5°, an indigo blue substance is obtained, which is soluble in concentrated sulphuric acid to a blue to bluish-black solution. A solution of phenanthraquinone in acetic acid on treatment with pyrrole and acetic acid yields a brown precipitate soluble in chloroform with a violet-red color. An aqueous solution of benzoquinone when treated with pyrrole and dilute sulphuric acid yields a dark-green pre- cipitate. Iodol— Tetraiodo Pyrrole, C4I4NH Iodol is a grayish-brown powder prepared by the action of iodin in potassium iodide on a solution of pyrrole in the presence of alkali. It SYNTHETIC ORGANIC NITROGEN COMPOUNDS 813 has a faint odor, and on heating is decomposed without melting between 140-150°. It is only slightly soluble in water, but dissolves in the ordinary organic solvents and in acids. It is turned black by hydrochloric acid, and forms an addition compound with eucalyptol, melting with decompo- sition at 112°. With sulphuric acid it gives a green color changing to violet, and on warming an alcoholic solution with nitric acid a bright- red color appears. Iodol is valuable chiefly as an antiseptic and alterative, and is used in syphilis, scrofula, etc., as a substitute for potassium iodide. Locally it is employed as a spray for throat affections, and as an ointment or powder or with collodion in chancre, chronic ulcers, and other suppur- ative conditions. A compound of iodol and egg albumen is recommended for internal administration. It is a yellow, tasteless, and odorless powder, soluble only in dilute alkalies. Quinolin and its Derivatives Quinolin, C9H7N, and its isomer, isoquinolin, occur in bone oil and coal tar, but for commercial purposes quinolin is prepared syn- thetically by Skraup's reaction. Anilin and glycerol are heated with a dehydrating agent such as sulphuric acid and an oxidizing agent such as nitrobenzol. In the reaction it is probable that acrolein is first formed, which then condenses with anilin, forming acrylanilin, and the latter under the oxidizing action of nitrobenzol loses two atoms of hydrogen and is converted to quinolin. H H • HC C CH I I I +H 2 HC C CH \ C /\ N / H Derivatives of quinolin may be obtained by Skraup's reaction, using derivatives or homologues of anilin. Quinolin is a colorless highly refractive oil, sp. gr. 1.095 at 20°, boil- ing 239° C, the commercial boils 230-234°, with a peculiar characteristic odor. It is sparingly soluble in water, but dissolves freely in dilute acids, forming well-defined salts of the composition X-HC1. It forms double salts with hydrogen platinic chloride and with potassium bichromate. The latter is sparingly soluble in water and may be obtained on adding potassium bichromate to a solution of the hydrochloride; it melts at 164-167° C. 814 ORGANIC SUBSTANCES Isoquinolin is a solid melting 22°, boiling 241° C. It has a faint odor resembling benzaldehyde. Quinolin is quite soluble in hot water, but only slightly in cold water. It dissolves easily in all of the ordinary organic solvents and acids. From acid solutions or neutral solutions of its salts quinolin is completely dis- placed by alkalies, and may be shaken out with ether and recovered. It is precipitated by iodin, potassium mercuric iodide, phospho- molybdic acid, picric acid, and potassium ferrocyanide in acid solution. The picrate forms bright-yellow needles melting 205°. The platino- chloride may be crystallized from hot dilute hydrochloric acid, in yellow needles containing 2H2O, melting 225°, and from hot water in small needles with IH2O, melting 218° C. Quinolin also forms soluble salts with acids, the hydrochloride, bisulphate, salicylate, and tartrate. The thiocyanate is used medicinally and the double salt of this acid with bismuth is marketed under the name " Crurin." Quinolin gives no characteristic color reactions with nitric acid or sulphuric acid or oxidizing agents. The tests of special value for its identification are its precipitation reactions and the melting-points of its purified crystalline salts. Quinolin and its salts are used in medicine for their antiseptic and antipyretic properties. It is used as a mouth wash and gargle, especially in diphtheria, as an intestinal antiseptic in dysentery, and for irrigating purposes in venereal diseases. It also has a wide use as a vaginal douche. The tartrate is given for intermittent fever. If it is desired to determine the amount of quinolin in a salt or its solution, the base should be liberated with alkali, shaken out with ether, the ether solution washed, shaken out with a known volume of standard acid, and after separating the acid the excess can be titrated with standard alkali, using methyl red as an indicator. One mil N/10 H2S04 = . 004619 gram quinolin. Crurin— Quinolin-Bismuth. Sulphocyanate, (C 9 H 7 N-HCSN) 3 Bi(SCN)3 It is a fine, brick-red, crystalline powder, with a slight odor of quinolin, insoluble in alcohol and ether, but soluble in acetone and slightly so in pure glycerin. It is decomposed by water with formation, it is stated, of soluble quinolin sulphocyanate, free sulphocyanic acid, and insoluble basic bismuth sulphocyanate or bismuth hydroxide. When crurin is decomposed by water there is formed an insoluble yellow compound and a solution which responds to tests for sulphocyanate in that it yields a deep-red color with ferric chloride and a white precipi- tate with silver nitrate solution, and to tests for quinolin, in that treatment with iodin in potassium iodide solution yields a reddish-brown precipi- SYNTHETIC ORGANIC NITROGEN COMPOUNDS 815 tate insoluble in hydrochloric acid; with picric acid solution it yields a yellow precipitate; with potassium ferrocyanide solution a green pre- cipitate is formed, and with potassium mercuric iodide solution it yields a reddish-yellow precipitate, which dissolves on heating. The yellow insoluble compound, when treated with potassium iodide solution, becomes orange colored, and it responds to tests for bismuth. Crurin treated with dilute nitric acid dissolves with formation of a solution from which bismuth can be separated by precipitation with hydrogen sulphide for quantitative estimation and in which the sulphocy- anate content can be determined by titration with standardized silver nitrate solution. It is useful as a local application for gonorrhea. It is also used in the treatment of ulcers of the leg. Quinoiodin or Chinoiodin is a chlorin-iodin addition product of quinoline, C9H7NICI. It is a yellow powder soluble in alcohol and insolu- ble in water, used as an antiseptic in dusting powders and petrolatum ointments. Iodolin — Quinolin Chloriodomethylchloride, C 9 H 7 NCH 3 C1CH ,Iodolin is a yellow powder soluble in alcohol and slightly in water, also used as an antiseptic. Quinolin gives rise to a number of important derivatives. yCH * CH2 Tetrahydroquinolin, Coih^ , boils 245-251° C, soluble in alco- \NHCH 2 hoi and ether and slightly in water and gives a platinochloride which melts 200°. This is a secondary base, yielding nitrosamin and capable of alkylation. It has strong antiseptic properties. Tetrahydroisoquinolin boils 232° and is soluble in alcohol, water, and ether. 8-Hydroxyquinolin, OHC 9 H 6 N This is the base of Chinosol, a widely advertised antiseptic. It has a characteristic saffron-like odor, melts 75-76°, is volatile with steam, and sublimes slowly at the ordinary temperature. It is soluble with difficulty in ether and cold water, but dissolves readily in chloroform, alcohol, acids, and dilute alkalies. Its acid and alkaline solutions are yellow, and a colorless alcoholic solution turns yellow when water is added. Its aqueous solution gives a green color with ferric chloride, and a red color followed by a black precipitate with ferrous sulphate. The hydroxyquinolin sulphonic acids are employed medicinally. 816 ORGANIC SUBSTANCES Vioform — Iodochloroxyquinolin — Nioform Vioform is iodo-chlor-hydroxy-quinolin, C9H4N • OH • I • CI. It is a voluminous, greenish-yellow powder; crystallizing from glacial acetic acid in needles melting at 177 to 178° C, practically odorless, and insoluble in water, and slightly soluble in alcohol. Vioform contains 41.57 per cent of iodin — it gives a green coloration with Millon's reagent or when the alcoholic solution is treated with ferric chloride solution. It dissolves with a brown color in concentrated sul- phuric acid and the solution evolves iodin on warming. If this solution, after driving off the iodin, is diluted with water, chlorine can be demo- strated by the usual test with silver nitrate. If a solution of vioform in chloroform is shaken with nitric acid, the chloroform acquires a violet- red color, and the nitric acid becomes somewhat yellow. It is antiseptic, and hemostatic. Analgen — 5-acetylamino-8-ethyoxyquicolin CH : C(NHCOCH 3 )C-CH=CH I II I CH=C(OC 2 H 5 ) C— N=CH This substance forms colorless crystals, melting 155°, readily soluble in alcohol, slightly in water, acidified solution yellowish red. The corresponding benzoyl compound is called Benzanalgen, Quinalgen, or Laborin, a white, tasteless crystalline powder melting 208°, readily soluble in dilute acids. Loretin — 7 iodo-8-hydroxyquinolin-5 Sulphonic Acid CH : C(S0 3 H) x I >C 5 H 3 N CI COH x Loretin is a colorless, tasteless, reddish-yellow crystalline powder which darkens on heating and evolves iodin at 260°. It is soluble in alcohol and water and in hot concentrated sulphuric acid without decom- position. The sodium salt is used as an antiseptic and is sometimes dispensed in combination with bismuth subnitrate. Loretin is also combined with iodoform, starch, talc, and magnesia, and is a component of many pencils, gauzes, etc., used in venereal diseases and for skin affections. The solu- ble form is sometimes called " Griserin." Argentol or silver quinaseptolate is the silver salt of hydroxyquinolin sulphonic acid. It is a yellow powder, soluble with difficulty in water. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 817 Diaptherin is a combination of 8-hydroxy quinolin and p-phenol sulphonic acid, green crystals, melting 85°, moderately soluble in water, but with difficulty in alcohol. Ferric chloride gives a bluish-green color which becomes yellow on adding hydrochloric acid. It is used for rheu- matism and as an antiseptic. Diapthol — 7-hydroxyquinolin meta Sulphonic Acid Yellowish-white crystals melting 295°, fairly soluble in water and use- ful as an urinary antiseptic. Atophan Atophan is 2-phenyl-quinolin-4-carboxyic acid, C 9 H5N-C 6 Hs-COOH-2 :4 Atophan crystallizes in small colorless needles, melting at 208-209° C. It is insoluble in water, but readily soluble in alkalies, hot alcohol, and boiling glacial acetic acid. It has a slightly bitter taste. Atophan is used in the treatment of gout and rheumatic conditions, Novatophan Novatophan is ethyl 6-methyl-2-phenyl-quinolin-4-carboxylate, CH3-C 9 H4N-C6H5COOC2H5, 6:2:4, the ethyl ester of paratophan, (6-methyl-2-phenyl-2-quinolin-4-carboxylic acid) . It is a slightly yellow, odorless, and tasteless crystalline powder, melt- ing at 76°. It is insoluble in water, but readily soluble in alkalies, hot alcohol, and strong acids. If 0.1 to 0.2 gram novatophan is boiled for a short time with 0.5 mil sodium hydroxide solution, then 5 mils iodin test solution added and again heated, the odor of iodoform will be apparent. When dissolved in concentrated sulphuric acid, a light-yellow solu- tion results which on the addition of bromin water yields a reddish- yellow precipitate. On adding ferric chloride to an alcoholic solution of novatophan a yellow, not a brown color, is produced. Paratophan Paratophan is methyl-atophan, 6-methyl-2-phenyl-quinolin-4-car- boxylic acid, CH 3 C 9 H 4 N • C 6 H 5 • COOH, 6:2:4. It is a yellow crystalline powder melting at 228Vsoluble in alcohol, ether, chloroform, and alkalies, but insoluble in water. It has a slightly bitter taste and a faint odor. 818 ORGANIC SUBSTANCES Wiien dissolved in concentrated sulphuric acid a light-yellow solu- tion results, which yields a light-yellow precipitate on the addition of bromin water. If ferric chloride solution is added to an alcoholic solution of para- tophan, a brown color is produced. If paratophan is heated above its melting-point carbon dioxide is liberated and methyl-phenyl-quinoline, CH3C9H5N • C6H5, melting at 68° is produced. Thalline — 6-methoxytetrahydroquinolin Thalline is prepared by heating p-aminoanisole and p-nitroanisole with glycerol and sulphuric acid and subsequent reduction. The free base crystallizes in colorless prisms, melting 42°, boiling 283°, pungent, sparingly soluble in water but readily in alcohol, ether, chloroform, and benzol. Thalline is usually marketed as the sulphate which is readily soluble in water. An aqueous solution gives precipitates with the general alka- loidal precipitants and alkalies; ferric chloride added to very dilute solu- tions produces a yellow color, changing to emerald green and finally pass- ing to red; and a green color may also be obtained with gold chloride, mercuric chloride, silver nitrate, chlorine water, and in acid solution with bleaching powder and potassium ferrocyanide. /3-naphthaquinone in aqueous solution treated with a solution of thalline sulphate and a drop or two of sodium hydroxide yields a red color, made more brilliant by nitric acid and soluble in ether or chloroform. The free base dissolves in sulphuric acid without color, but the addition of nitric acid causes a deep-red color changing to a yellowish red. Sul- phuric acid containing sugar produces a red color. The sulphate is used in yellow fever. An addition compound of thai- line and iodin is used for carcinoma. Orexine — 3-phenyl-3, 4-dihydroquinazolin The base of orexine is a derivative of a quinazoline and is obtained by treating formanilid sodium with o-nitrobenzyl chloride and reducing the ortho-nitrobenzylformanilid, C 6 H4< >NC 6 H 5 X CH 2 — / Orexine is the hydrochloride of the base, but the term is applied indis- criminately to the base and the hydrochloride, for there is a substance called orexine tannate which is claimed to be a tannate of the base. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 819 The base is soluble in alcohol, ether, and chloroform, but dissolves in acids and is thrown out of acid solution by alkalies. A solution of the base is precipitated by mercuric chloride, the deposit dissolves in hot water, but crystallizes out on cooling. The precipitate with potassium bichromate has similar properties. Bromin water is decolorized, and a yellow amorphous precipitate thrown down; tannin produces a pre- cipitate and permanganate undergoes reduction. The solid substance when heated with zinc dust evolves phenyl-isocyanide, and the residue, on treatment with hydrochloric acid, filtering and adding calcium hypo- chlorite solution, gives the blue color characteristic of anilin. A solu- tion of the base in concentrated sulphuric acid is colored green by nitric acid, a reddish color appearing on the edges. Orexine hydrochloride crystallizes with 2 molecules of water, G14H12N2HCI+2H2O It produces violent sneezing, and in medicine is used as a tonic and stomachic. The tannate is almost insoluble in water, but dissolves in dilute hydro- chloric acid. It gives the characteristic reaction of a tannate, and the base may be precipitated by alkali from a solution in 30 per cent acetic acid. Phenylene-diamines — Diaminobenzenes, C 6 H 4 (NH 2 )2 There are three modifications, ortho, melting 102-103°; meta, melting 63°; para, melting 140°; boiling respectively 252°, 287°, 267°. Sodium nitrite, added to neutral aqueous solutions, give with separation of amino-azo-phenylene as a colorless oily liquid, with m-yellow or brown color or precipitate of triamino-azobenzene, with p- no color. The meta is easily removed from alkaline solutions by ether. The hydrochloride is a well-defined salt, known commercially as Lentin. The meta-compound is used in acute bowel trouble where an anti- septic is required. The para is used as a hair dye. A solution of the base in weak potas- sium hydroxide when mixed with hydrogen peroxide develops a black color, and with ferric chloride a brown. In case of poisoning caused by hair dyes, this substance or a diamino toluene may be suspected. Paraphenylene diamine is prepared directly from acetanilid by nitra- tion and subsequent reduction. This fact should be borne in mind by the control chemist who may be called upon to testify in cases involving the analysis of a preparation containing the base. It is of course question- able whether a hair dye is a medicine or a drug, being more properly a cosmetic, which is not subject to the drug act as it is at present interpreted. 820 ORGANIC SUBSTANCES Methylene Blue, Ci 6 Hi 8 N 3 SCl. Tetramethylthionine Methylene blue is an oxidation product of dimethyl para-phenylenedi- amine in hydrogen sulphide solution. The medicinal product should be free from zinc chloride. It is a dark-green or red-brown bronzy powder, readily soluble in water to a deep-blue solution, and is removable from an alkaline solution with ether. It dyes cotton mordanted with tannin a blue color which is fast to light and soap. Methylene blue has attained its greatest reputation as a remedy for gonorrhea, and is usually dispensed in capsules or pills. It will be found by itself and in combination with copaiba, and oils of santalwood and cinnamon, methyl salicylate, and haarlem oil. It is the ingredient of kidney remedies advertised to the laity, the literature of which admonishes the patient to observe the urine after taking, and if it acquires a greenish color he may know the remedy is doing its work. These remedies, usually in the pill form, may contain in addition to methylene blue, buchu, juniper, potassium acetate or nitrate, copaiba, cubeb, methyl salicylate, aloes, extracts of Eupatorium, triticum, Pichi, Chondrodendron tormentosum, Hydrangea, cornsilk, and others. Toluylene-diamines — Diaminotoluenes, C 6 H 3 (CH 3 ) (NH 2 ) 2 The substances occur in two types, the alpha and beta. The former is the ortho-para modification (1-2-4), melting 99°, and the latter the meta-para (1-3-4). They closely resemble the phenylene diamines. Comparative reactions of these two substances in neutral or slightly acid solutions have been reported as follows : Ferric Chloride. Alpha — No change at first, orange on long standing. Beta — Wine-red color. Potassium Bichromate. Alpha — Yellowish-brown color. Beta — Reddish-brown precipitate. Potassium Ferricyanide. Alpha — Olive-green crystalline plates. Beta — Dark-red color. Bromin Water. Alpha — Yellowish-white precipitate. Beta — Brown flocks, magenta-red solution. Potassium Nitrite. Alpha — Golden-brown color, dilute. Brown precipi- tate when concentrated. Beta — Salmon-red precipitate. Bleaching Powder Solution. Alpha — Reddish-brown color, light brownish- yellow precipitate. Beta — Dark-red color. Olive-green precipitate. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 821 These bodies are used in hair dyes. The treatment consists of either a solution of the diamine in alkali; or an amount of the crystalline sub- stance sufficient for an application and another bottle containing a reagent which, when mixed with it, will bring out the requisite color. AMIDES Amides may be considered as substituted ammonias in which the hydrogen has been replaced by an acid radicle. There are three classes, primary, secondary, and tertiary. H N— COCH3 HN=(COCH3) 2 N(COCH3) 3 H Acetamide, CH3CONH2, may be obtained by the interreaction of acetyl chloride or acetic anhydride with ammonia, or by distilling ammo- nium acetate in a stream of dry ammonia gas. It crystallizes in colorless, deliquescent needles, melting 80-82° and boiling 222° C. It is almost odorless when pure, but as usually found has a strong mousy odor. It dissolves in water and alcohol and when heated with mineral acids or alkalies is decomposed into acetic acid and ammonia or their salts. On distillation with phosphoric anhydride it loses a molecule of water and is converted into methyl cyanide or acenitrile, CH3CONH2 = CH3CN+H2O. Neuronal— Diethylbromacetamide, Br(CoH 5 ) 2 CONH 2 Neuronal is a white crystalline powder, with a camphoraceous odor and a bitter, cooling taste. It melts 66-67° C. and is somewhat soluble in water, readily in alcohol and ether. It is used as an hypnotic. When heated with dilute sodium hydroxide, sodium bromide and cyanide are produced and diethylketone set free. Salicylamide, C 6 H 4 (OH)CONH 2 Salicylamide is a colorless crystalline substance, melting 138° C, soluble in alcohol, ether, chloroform, and slightly in water. Tt is used as a remedy for rheumatism and fevers and has antiseptic properties like salicylic acid, which it resembles in those reactions which are characteristic of the phenolic group. 822 ORGANIC SUBSTANCES pmiy Valeric Acid Diethylamide, CH 3 CH 2 CH 2 CH 2 CO This body, known as Valyl, is a colorless liquid with a methyl-like odor, boiling 210° C, soluble in alcohol, ether and somewhat in water. It has hypnotic and antineuralgic properties, and is employed in nervous troubles. .NH 2 Urea and Its Derivatives Urea, C=0 , or carbamide, is the amide of the dibasic carbonic \nh 2 acid, C=0 . It is a substance of great importance in physiological \)H chemistry, and methods for its detection and determination have been the subject of a vast amount of research. It is used in a limited way in medicine, but some of its derivatives have an extended use and are of considerable interest to the drug chemist. Urea is used in tuberculosis and as a diuretic. In renal calculus it is sometimes given in comparatively large doses. Urea forms transparent, colorless, somewhat hygroscopic prisms, odor- less, or with a faint odor suggestive of urine, melting at 132° and decom- posing at 150-160° with evolution of ammonia and formation of biuret. It may be distilled in vacuo at 135° C. It is very soluble in alcohol and cold water and much less in hot water. It is but slightly soluble in ether, and the other organic solvents have little or no action. On fusion with caustic alkalies, ammonia is evolved and a carbonate is formed. On heating with strong mineral acid carbon dioxide is given off and a salt of ammonia produced. Pure concentrated nitric acid com- bines with urea without decomposing it, but if nitrous acid is present, nitrogen and carbon dioxide are evolved. Urea forms salts which are dissociated by water, the nitrate and oxalate are easy to prepare, and the latter is but sparingly soluble in cold water. Urea is not precipitated by the usual alkaloidal reagents, nor does it give color tests with the oxidizing agents. When heated at 160° for some time, the residue dissolved in water and made slightly alkaline with sodium hydroxide, the addition of a dilute solution of cupric sulphate will produce a violet or red color. This is known as the biuret test. It is precipitated by mercuric nitrate from a solution free from chlorides and it is not precipitated by mercuric chloride. The mercuric nitrate SYNTHETIC ORGANIC NITROGEN COMPOUNDS 823 compound may be used to good advantage in the purification of urea, because it can be separated from the solution, washed and decomposed by hydrogen sulphide with liberation of the base. Adalin Adalin, C(C 2 H 5 )2Br • CONH • CONH 2 , is bromdiethyl-acetyl-carbamide. It is an almost colorless and odorless crystalline powder, with a melting- point of 116° C, which dissolves readily in alcohol as well as in the other ordinary organic solvents. It is difficultly soluble in water. It is used as a sedative and mild hypnotic. Bromural Bromural, (CH 3 -CH(CH 3 )CHBrCO)HN-CONH 2 , is 2-mono-brom- isovaleryl-urea. It forms small, white, almost tasteless needles which are easily soluble in hot water, ether, alcohol, and alkalies, but less readily in cold water. It sublimes on heating and melts in the neighborhood of 145° C. Bromural can be precipitated from a 10 per cent sodium hydroxide solution with acids. The presence of bromin may be demonstrated by fusion with sodium carbonate and potassium nitrate and testing for a bromide with silver nitrate solution. On heating the alcoholic solution of bromural with sodium ethylate for several hours on the water-bath, sodium bromide will precipitate. If this is filtered off and the filtrate evaporated, a crystalline mass will remain which can be recrystallized from water. This is dimethylacrylic acid, melting at 280° C. If 1 gram bromural is boiled for about one minute with 10 per cent solution of sodium hydroxide, ammonia obtained from the urea will be given off. If the hot liquid is then cooled, acidified with nitric acid and extracted with ether, and the ether evaporated, an oily fluid, 1-brom- isovaleric acid, which has the specific odor of valeric acid, will remain. The biuret reaction cannot be obtained. On melting bromural and adding concentrated sodium hydroxide solution and copper sulphate, no color reaction will take place. Bromural is a nerve sedative. | Thiosinamine^-Allyl Sulphocarbamide — ^llyljrhiourea^ — Rhodaline Thiosinamine is allyl-thio-urea, (NH 2 ) • CS • NHCH 2 • CH : CH 2 . It forms colorless crystals, having a slight alliaceous odor and bitter taste and melting at 74° C. It is moderately soluble in water, but is decomposed by this solvent. It is soluble in about 3 parts of alcohol and readily soluble in ether. 824 ORGANIC SUBSTANCES It is used by hypodermic injection in lupus, chronic glandular tumors, and by mouth in stricture, corneal opacity, chronic deafness. Fibrolysin Fibrolysin, (NH 2 • CS • NHCH 2 • CH : CH 2 )+C 6 H4(OH)(COONa), is a sterilized solution of a double salt of thiosinamine and sodium salicylate containing 15 per cent of the double salt. The tests are those of thiosinamine and sodium salicylate. Maretin— Metatolylhydrazine Carbaminate, CeH^CHsNHNHCONHa Maretin forms colorless, lustrous crystals, melting 183-184°, some- what soluble in alcohol, but only slightly in ether, chloroform, and water. It is an antipyretic. Ethyl Carbamate — Urethane When urea or its nitrate are heated to 100° C. with alcohol, ethyl / OC 2 H 5 carbamate, C=0 , is formed. It is a colorless c^stalline substance, \nh 2 with a faint peculiar odor and a saline taste, melting 48-50° and boiling 180° C. It is readily soluble in water, alcohol, ether, chloroform, and glycerin. On warming with concentrated sulphuric acid, carbon dioxide is evolved and alcohol and ammonium bisulphate remain in solution. On warming with concentrated alkali, ammonia gas is given off. An aqueous solution treated with sodium carbonate and a little iodin, will deposit iodoform on warming. Its aqueous solution gives no precipi- tate with nitric acid, mercuric nitrate, or oxalic acid. Urethane is used as a sedative, hypnotic, and antispasmodic, and will be found in remedies for insomnia, nervousness, and tetanic poisons. Urethane forms a compound with chloral having the composition CCl3CH(OH)(NH)COOC 2 H 5 , and known as chloralurethane, furalium, ural, or uraline. It melts 103° C. and is soluble in alcohol and ether. This substance is also used as an hypnotic. /_Jpthylidene urethane, CH 3 CH(CO(NH)OC 2 H 5 ) 2 , is a crystalline body melting 125-126° resulting from the action of hydrochloric acid on a solu- tion of urethane in acetaldehyde. /OC 2 H 5 Phenyl urethane, CO , is closely allied to urethane. It is NsiHCeHs called Euphorin. The product is prepared b}^ the action of anilin on the ethyl ester of chloroformic acid. It occurs in the form of colorless SYNTHETIC ORGANIC NITROGEN COMPOUNDS 825 needles or a white powder with a faint odor and a clove-like taste, melting 50-51°. It is but slightly soluble in water, but soluble in dilute alcohol, strong alcohol and ether. It is used internally for rheumatism, sciatica, and headache, and externally as a dusting powder for venereal sores, skin diseases, etc. Hedonal — Methylpropylcarbinol Urethane Hedonal is pentan-2-ol urethane, CH 3 • CH 2 • CH 2 • CH(CH 3 )0 • CO • NH 2 . It is a white, crystalline powder, having a faint aromatic odor and taste, melting at 74° C, and boiling at 215° C. It dissolves in 120 parts of water at 37° C. but is more soluble at higher temperatures and is readily soluble in alcohol, ether, chloroform, and other organic solvents. It is readily volatilized with the vapors of water or alcohol, and when boiled with alkalies is split up into its constituents, methylpropylcarbinol, ammonia, and carbon dioxide. On boiling with dilute sodium hydroxide, ammonia is evolved and recognized by the odor and the usual reactions; if then an aqueous solu- tion of iodin in potassium iodide is added, and the mixture allowed to cool, the odor of iodoform derived from the alcohol is distinctly manifested. Hedonal appears to have a greater hypnotic effect than ethyl car- bamate, Neurodin — Acetylparaoxyphenylurethane /OC2H5 c=o ^NHOCOCHsCeHi Neurodin may be considered as a derivative of amido phenol as well as of urea. It forms colorless crystals, melting 87° C, which are slightly soluble in water. It is used as an antipyretic and antineuralgic. Thermodin is claimed to be acetyl paraethyoxyphenyurethane, hence it should stand in close relationship to the last-named substance. Barbituric Acid and Its Derivatives When urea and malonic acid react under proper conditions, barbi- 'NH|ITOH|CO turic acid results, C=0 ")CH 2 . In this body the central NH H OH CO hydrogen atoms have acid properties. 826 ORGANIC SUBSTANCES Veronal — Diethyl Malonyl Urea Veronal is diethyl-barbituric acid, 2, 4, 6-trioxy-5-diethyl pyramidin, .NHCO C 2 H 5 co Nc/ \nH-CO C2H5 a ureide derived from diethylmalonic acid, COOHC^Hs^COOH, and urea, CO(NH 2 ) 2 . It is a white, crystalline powder, melting at about 188-191° C, sub- liming on heating, odorless and faintly bitter. It is soluble in about 150 parts of cold water and in about 12 parts of boiling water. It is quite soluble in ether, acetone and ethyl acetate ; also slightly soluble in chloro- form, petroleum benzine, acetic acid, and amyl alcohol. It forms salts with alkalies which are soluble in water. Prolonged heating with sodium carbonate solution liberates ammonia. Denige's reagent produces a white precipitate; Millon's reagent produces in solution acidulated with nitric acid a precipitate soluble in excess of the reagent. When added to potassium hydroxide, fused in a nickel crucible, and heated for two minutes, the cold mass on dissolving in water should give a blue precipitate with ferrous sulphate; on adding excess of acid and shaking with ether, an oily mass is extracted, having the odor of rancid butter, soluble in water, and giving a wine-red color with ferric chloride. A so-called salt of the above ureide with sodium is marketed as Veronal- sodium, as Medinal and probably other designations. It is soluble in 5 parts of water. Veronal is an hypnotic. Proponal — Bipropylmalonylurea /NH-CO C3H7 0=0 \ \ C3H7 Proponal is closely allied to veronal, dipropylmalonic acid being used in the synthesis instead of the diethyl compound. It forms colorless crystals slightly soluble in cold water, more readily in hot, and easily in alcohol, ether, chloroform and alkalies. It melts 14£°- It is used for the same purposes as veronal. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 827 Luminal — Phenyl-ethyl-barbituric Acid — Phenyl-ethyl-malonyl-urea Luminal is phenyl-ethyl-barbituric acid, 2, 4, 6-trioxy-5-phenyl-ethyl pyramidin, /NH-CO C 6 H 5 do >c/ \nHCO C2H5 Luminal is a white, odorless, slightly bitter powder. It is almost insoluble in cold water, slightly soluble in hot water and readily soluble in alcohol, ether, and chloroform, and in alkaline solutions. It crystal- lizes from boiling water to lustrous leaflets, and is precipitated unchanged by acids from its alkaline solutions. It melts at 173-174° C. If about 0.3 gram is shaken for a short time with 1 mil of normal sodium hydroxide and 5 mils of water, and the mixture filtered, the filtrate will yield white precipitates on the addition of mercuric chloride and of silver nitrate solutions. If about 1 gram is boiled for five minutes in 10 mils of a 50 per cent solution of sodium rrydroxide, ammonia will be evolved. If about 1 gram is dissolved in 5 mils of normal sodium hydroxide and the solution heated for four hours on a boiling water-bath, the evapo- rated water being replaced, crystals of pheny-acetyl-urea will separate on cooling. When recrystallized from dilute alcohol these crystals melt at 147° C. Luminal is used as an hypnotic in nervous insomnia and conditions of excitement of the nervous system. Adrenalin — Epinephrin The suprarenal glands of sheep and other animals contain a basic substance which has a strong physiological action causing a rise in the blood pressure, and is used in hemorrhage, catarrhal, and congestive conditions. The blood pressure raising principle has been separated and purified and is now a commercial article being sold under several names, adnephrin, adrenalin, adrin, epinephrin, supracapsulin, suprarenalin, etc. Some controversy has arisen as to the name which was first applied to this substance before its composition was known, but the merits of the case need not be discussed here. The active principle is usually marketed in a weak solution (1 : 1000) of the hydrochloride, and as it is very unstable, some preservative such as chloretone is added to the solution, and it is further inertized by satu-^ rating with carbon dioxide. There is also a large demand for the desic- cated glands and their extract. 828 ORGANIC SUBSTANCES The active principle is sometimes combined with cocain and with spartein in tablets, it is also formulated with sodium chloride and boric acid in order to yield a non-irritant solution. It is put up in oily mix- tures to be used as a nasal spray and in ointments and suppositories. The oily inhalants usually contain alcohol. Its use is extending to com- plex lotions and ointments, but it is of such an unstable nature that the value in these products is questionable. Epinephrin is 1, 2-dihydroxy-4 2 -methylamino ethyl-4 1 -ol benzene, CeHs (OH) 2 (CHOH • CH 2 NHCH 3 ) . It is a finely crystalline white or yellowish powder, odorless and slightly bitter. It melts at 201-207° C, turning brown and decomposing at the higher temperature. It shows a slightly alkaline reaction to moistened red litmus paper. It is almost insoluble in cold water, more readily in hot water. It is difficultly soluble in alcohol and insoluble in ether. The colorless aqueous solution is easily oxidized on contact with the air, becoming pink, then red, and eventually brown. The base reacts with acids to form salts which are readily soluble in water; it is also soluble in the fixed alkalies, but not in ammonium hydroxide or in solutions of the alkaline carbon- ates. The following reactions are the most characteristic: The addition of ferric chloride to a solution of the alkaloid produces a beautiful emerald- green color which by careful addition of caustic alkali becomes purple, and then carmine red. Strong acid prevents the reaction with ferric chloride, limiting the change of color to a dirty yellowish-green. It gives a vivid pink color with iodin. The alkaloid reduces silver salts and gold chloride very energetically, and the liquid turns red. A drop of 1 : 10,000 solution instilled into the eye will, within a few seconds, pro- duce a pallor of the conjunctiva. L-Suprarenin Synthetic L-suprarenin synthetic is epinephrin produced synthetically accord- ing to the method of Stolz and Flaecher. 1 It is a white, odorless powder nearly insoluble in water, alcohol, and ether. It melts at 211-212°. It has the power of rotating polarized light to the left: , , 19.6° K1 AO (a) -g-= -51.4 . It has the chemical and physical properties and physiologic effect of natural epinephrin obtained from suprarenal glands. Methods for the determination of adrenalin in order to arrive at a 1 Ztschr. f. physiol. Chem., 58, p. 189. SYNTHETIC ORGANIC NITROGEN COMPOUNDS 829 standard for desiccated suprarenal glands, have been the subject of much study. Hale and Seidell published a method based on a color comparison with platinic chloride and cobalt chloride, Folin, Cannon, and Denis recommended the use of phosphotungstic acid, and later Seidell sub- stituted gold chloride for platinic chloride in his original method. These procedures in the order of their appearance are included. Method of Hale and Seidell. 1 — .01 gram of the desiccated gland is treated with 5 mils dilute hydrochloric acid and 5 mils potassium iodate solution 0.2 per cent, heated just to boiling, allowed to stand fifteen minutes, filtered and the color compared with a series of standards. The latter are made up from a mixture of potassium platinic chloride and cobalt chloride solutions, which develop a color similar to that given by epinephrin and potassium iodate and which have been previously stand- ardized against the ash-free active principle. The yellowish extractive matter present in the aqueous solution interferes with the test, but may be obviated by using a small quantity of the sample and not diluting. Method of O. Folin, W. B. Cannon, and W. Denis. 2 — The glands are extracted with N/10 hydrochloric acid and water, the mixture being finally heated to boiling. After the addition of sodium acetate solution and further boiling, the mixture is diluted with water and filtered or centri- f aged to obtain a clear extract. As a rule, 100 mils of extract are obtained from 2 grams of gland. Five mils are put into a 100-mil flask and 1 mil fresh uric acid solution containing .0010 gram of the acid is put into another flask. A special reagent is then made as follows: 100 grams sodium tungstate and 80 mils of 85 per cent phosphoric acid are boiled gently with 750 mils water for two hours and then made up to 1 liter. Ttt-o mils of the reagent and 20 mils of saturated sodium carbonate solu- tion are added to each of the 100-mil flasks, allowed to stand for a few minutes, shaken and made up to the mark. The colors of the deep-blue liquids are compared in a Duboscq colorimeter. The amount of epine- phrin can be calculated from the fact that it produces three times as much color as an equal weight of uric acid. Johannesohn used this method for estimating epinephrin in ordinary commercial preparations, but found it inapplicable in the presence of novocain or alypin. Method of A. Seidell. 3 — 0.01 gram of the sample is shaken with 0.005 gram of manganese dioxide and 10 mils water and after standing one hour the mixture is filtered into a test-tube and the color compared with that of a color standard in a tube of similar dimensions. The color l Am. J. Pharm., 83, 551. 2 J. Biol. Chem., 1913, 13, 472. 3 J. Biol. Chem., 1913, 15, 197. 830 ORGANIC SUBSTANCES standards are prepared from solutions of cobalt chloride 2 per cent (with 1 mil cone. HC1) and gold chloride 0.1 per cent as shown in the following table : Color Standard Epinephrin Cobalt Solution Gold Solution Water Gram Mils Mils Mils .00001 1.15 .70 8.15 .00002 1.85 .95 7.20 .00003 2.40 1.10 6.50 .00004 2.95 1.25 5.80 .00005 3.50 1.30 5.20 .00006 4.05 1.35 4.60 .00008 5.15 1.55 3.30 .00010 6.30 1.75 1.95 The oxidation product of epinephrin which results when a solution of the base is treated with an excess of ammonia, is soluble in amyl alcohol, but does not dissolve in chloroform, ether, or petroleum ether. It gives a bluish-green color with a very dilute solution of potassium ferricyanide containing ferric chloride, and a blue color with an ammoniacal solution of phosphomolybdic acid. It does not respond to the other character- istic reactions for epinephrin according to Venturoli and Gailbrani, 1 who have made a study of the oxy body. Tyramine Tyramine is para-hydroxy-phenyl-ethyl-amine hydrochloride OH ■ C 6 H 4 • CH 2 • CH 2 • NH 2 • HC1 The base para-hydroxy-phenyl-ethyl-amine was first isolated by Barger from ergot and also prepared synthetically by him by the reduc- tion of para-hydroxy-acetonitrile with sodium in alcoholic solution. It is chemically and physiologically related to epinephrin (C6Hs(OH)2 (CHOHCH2NHCH3). Tyramine occurs as an almost white crystalline powder, easily soluble in water, forming a neutral solution. Taken internally or injected subcutaneously tyramine increases the blood pressure; for this reason it can be used in shock or collapse; it is also claimed to be valuable for producing post-partum contraction of the uterus. It is useless as a local hemostatic. 1 Giom. Farm. Chun., 1911, 60, 97. CHAPTER XXI ANILIDES AND PHENETIDINS ANILIN, C 6 H 5 NH 2 Anilin is an important substance in the chemistry of medicinal products, but it is seldom used itself as a drug. Its properties are anti- septic. It is one of the intermediary products formed in the quantitative estimation of acetanilid, and it results in the hydrolysis of some closely allied chemicals whose identity it may help to establish. Hence it. is advisable to be thoroughly familiar with the properties of anilin and /OK also the analogous compounds, amino phenols, C6ELi\ , which are X NH 2 obtained by the reduction of nitro phenols, while anilin comes from nitro benzol. The pure substance is colorless, but it becomes yellow or brown on exposure to light and air due to oxidation. It is of oily consistency, sp. gr. 1.0254 at 15° C, solidifying 6°, boiling 184°. It is but slightly soluble in water, but dissolves easily in alcohol, ether, chloroform, acetone, and acid liquids. It is thrown out of an acid solution by excess of alkali, and can be recovered unchanged by shaking with ether. It dissolves sulphur, phosphorus, and colophony, but not caoutchouc nor copal. It combines readily with bromin to form tribromanilin, and the aqueous solution of anilin gives an immediate precipitate if treated with bromin water or bromide-bromate reagent. Anilin is a strong base, forming well-defined stable salts with acids of the composition of CeHjN-HR. A cold aqueous solution of an anilin salt is converted into a salt of diazo benzene when treated with nitrous acid or a nitrite and mineral acid, and on subsequent boiling phenol is produced with evolution of nitrogen. Anilin gives the well-known and disagreeable carbylamine reaction when warmed with chloroform and potassium hydroxide. With sulphuric acid and manganese dioxide a purple color results, and purplish shades are given under the same conditions in presence of other oxidizing agents. The reactions somewhat simulating those of strychnin. Nitric acid gives a purple color in the cold, changing to indigo blue and then to greenish blue on heating over the steam-bath, then as the reaction becomes more 831 832 ORGANIC SUBSTANCES violent a brownish-black shade develops. The residue gives an aromatic odor with alcoholic potash. When a small amount of anilin is treated with an aqueous solution of carbolic acid followed by a solution of bleaching powder, yellow streaks, changing to greenish blue, are obtained. If anilin is treated with 2 to 3 drops of dilute solution of bleaching powder 1 in 200, in such a manner that the two liquids do not mix, a purple or blue color will form at the junction of the liquids. Anilin combines with equivalent amounts of dilute and concentrated acids, except nitric to form salts, and it furthermore yields stable deriv- atives on treatment with excess of acids and subjecting to higher tempera- tures, thus with sulphuric acid a series of annno-benzene sulphonic acids, C6H4 • NH2SO3OH, result, and with acetic acid, acetanilid, C 6 H 5 NH-COCH 3 , is formed. Nitric acid, when dilute, converts anilin to nitranilins and when con- centrated to quinone and other substances. If a solution of anilin in concentrated hydrochloric acid 1 in 3 diluted with an equal volume of water is diazotized with sodium nitrite and the diazotized solution saturated with dry sodium chloride and poured off from any undissolved salt, the ice-cold solution, when treated with stan- nous chloride in concentrated hydrochloric acid, 6 to 2 J (in proportion to the anilin used) will separate out phenylhydrazine hydrochloride after several hours standing. This reaction is of interest to the drug chemist, from a theoretical point of view, because antipyrin can be prepared from phenylhydrazine. We have thus an anomalous situation in control work for antipyrin, though not an inhibited drug, can be obtained directly from anilin, the base substance of acetanilid, while acetphenetidin, which is not made from anilin at all, but from amino phenol, is classed as a derivative of acetanilid. Bromamide Bromamide is the hydrobromide of tribromanilin, CelTtBrsNHBr. It forms colorless, odorless, tasteless needles, melting 154-155° C, soluble in chloroform, ether, and hot alcohol, but insoluble in water. It is used as an antipyretic, antineuralgic, and antirheumatic. Paraiodanilin, C 6 H 4 NH 2 1. 1-4 This a colorless to bluish crystalline substance, melting 60° C, soluble in alcohol, ether, and chloroform. Its hydrochloride is yellowish, soluble in alcohol and slightly in water. It is used as an antiseptic. The homologues of anilin have similar properties. ANILIDES AND PHENETIDINS 833 There are three toluidines and six xylidines; they are all liquids at the ordinary temperature except para-toluidin. Their identification or determination becomes a matter of moment when one is working with an abnormal specimen of some anilin derivative which is suspected of containing derivatives of its homologues. The acetyl derivatives of some of them are credited with possessing antipyretic properties and may sometimes be substituted for acetanilid. Melting-point Boiling-point Melting-point of acetyl derivat've Ortho-toluidin below -20° 199.5° 114° w-toluidin below -13° +45° 197 198 223 107 p-toluidin 65-66 ■u-ortho xylidin 1 : 2.3. . 134 a-ortho xylidin 1 : 2.4. . +49° 226 99 w-meta xylidin 1 : 3.2. . 216 176.8 a-meta xylidin 1 : 3.4. . 212 129 s-meta xylidin 1 : 3.5 . . g 220 140.5 Para xylidin 1 : 4.2 . . 213.5 139 ACETANILID, C 6 H 5 NHC 2 H 3 The anilides are derivatives of anilin in winch one or more of the hydrogen atoms of the amino group are replaced by acid radicles. The homologues yield similar derivatives and we therefore have toluides, xylidides, etc. Unquestionably the most important derivative of anilin in the realm of pharmaceutical chemistry is acetanilid. Tins substance, which also goes by the name of phenylacetamide and antifebrin, is sold in enormous quantities as an antipyretic and analgesic and in various combinations with cafTein, sodium bicarbonate, and bromides, occurs in by far the largest proportion of the headache mixtures sold on the market. Acetanilid is also used as an antirheumatic, anesthetic, and antiseptic, and for the latter purpose it will be found in hydrogen peroxide. Acetanilid is usually dispensed in tablets or powders. The com- binations include acetanilid with cafTein and bromides, usually sodium; with cafTein, bromides and sodium bicarbonate, sometimes with the addi- tion of codein or heroin or quinin sulphate; with salol; with morphin; with quinin sulphate, with Gelsemium; with bromides, hyoscyamin and digitalin; with cafTein and monobromated camphor; with salicylates, Gelsemium, monobromated camphor and hyoscyamin; with bromides, cafTein, Hyoscyamus and morphin; with quinin, Hyoscyamus, arsenic, strychnin and Cannabis; with quinin, bromides, aloin, cascara, and Capsicum. 834 ORGANIC SUBSTANCES Acetanilid will also be found in liquids usually of the elixir type, where it is combined with bromides and caffein, to which are often added codein, Gelsemium, salicylates, antipyrin, and other drugs in combina- tions similar to those occurring in tablets. Acetanilid is obtained by boiling a mixture of molecular proportions of anilin and glacial acetic acid under a reflux, and recrystallizing the resulting product out of water. It forms laminary crystals having a smooth feel, recalling that of boric acid, subliming at the temperature of the steam-bath, melting 111-113°, depending on the condition of its purity and distilling unchanged at 295°. It dissolves sparingly in cold water, but is fairly soluble in boiling water and readily dissolved by alcohol, ether, chloroform, or benzol. It is somewhat soluble in petroleum ether, and is removed from acid solutions by that solvent. Acetanilid is a weak base and does not form stable salts with acids, nor give any precipitate with Mayer's reagent, iodin solution, nor picric acid. It is easily removed from an acid solution by immiscible solvents. When warmed with potassium hydroxide and chloroform it yields phenyl isocyanide, thereby differing markedly from antipyrin and anti- phenetidin, though the latter often gives a suggestive odor. Its aqueous solution yields a precipitate with bromin water; this precipitate is a parabrom acetanilid, which is quite insoluble in water and melts 164-156° C. Acetphenetidin does not give any precipitate with bromin water. If this test is modified by digesting the acetanilid with dilute sulphuric acid 1 in 5, over the steam-bath for two or three hours and not allowing the hot acid to become concentrated enough to produce charring, the drug will be broken up into its basic substances, acetic acid evolved and anilin sulphate remaining in solution. The cold dilute solution will give a heavy flocculent precipitate with bromin water. Acetphenetidin under similar conditions yields phenetidin sul- phate, and a blue color results on adding bromin water. This procedure allows for the simultaneous identification of both substances if they occur together. If desired, the acid aqueous solution obtained by digesting the acet- anilid may be treated with excess sodium hydroxide and liberated anilin shaken out with ether. On boiling 0.1 gram of acetanilid for several minutes with 2 mils of hydrochloric acid and adding to the cool solution 3 mils of phenol 1 in 20 and a saturated solution of calcium hypochlorite, the mixture, which will be brownish red, will acquire a blue color with excess of ammonia water. Acetanilid dissolves without change in concentrated sulphuric acid, and remains unchanged if heated at the temperature of the water-bath for half an hour. After exposure for four to five hours at this temperature, ANILIDES AND PHENETIDINS 835 it is converted mostly to sulphanilic acid with a small amount of acet- sulphanilic acid. Acetphenetidin when heated for an hour or two with concentrated sulphuric acid at the temperature of the water-bath yields phenetidin sulphonic acid. If a little water is present there is an evolution of ethyl acetate and para-amidophenol is formed which is subsequently changed to the sulphonate. Watson 1 found that when acetanilid was mixed with boric acid in a porcelain dish and heated on a free flame an odor suggestive of sweet clover or arbutus was evolved and a yellow residue remained. Acet- phenetidin left a yellow residue, bat the odor was different and antipyrin gave a naphthalene odor and a pink residue. In the case of mixtures the odor was increased by adding a drop of water to the residue. As acetanilid is removable from acid solutions by means of immiscible solvents it will appear in the general scheme of shake-out analysis in all the fractions obtained by shaking out the acid mixture. It will, of course, appear in greatest amounts in the ether and chloroform fractions, but small quantities are removed by petroleum ether. If the acetanilid is unaccompanied by any other substance removable from acid solution by immiscible solvents, its identification is easy, for it can be recrystallized from water and its melting-point and other characteristic properties determined. The carbylamine test should be first applied and if negative no further concern is necessary. Caffein if present may be separated without difficulty by dissolving the residue in dilute hydrochloric acid and then throwing out the caffein with iodin. The acetanilid remains dissolved, and after the precipita- tion is complete, and filtration has been accomplished, it may be recovered from the filtrate by destroying the excess of iodin with sulphite, and then shaking out with chloroform. If it is desired to identify the caffein it is recovered from the iodin precipitate by solution in sulphite solution, and shaking out with chloroform from an ammoniacal mixture. The presence of antipyrin is indicated by treating with Mayer's reagent a portion of an aqueous solution of a suspected mixture, obtained by shaking out an acid solution with immiscible solvent. If a well-defined precipitate is obtained with this reagent and subsequent tests with picric acid and nitric solution give the characteristic antipyrin reactions, a separation of the acetanilid may be effected by dissolving the residue in hot water allowing enough to hold up the acetanilid when cool, and pre- cipitating the antipyrin with picric acid. On filtering the acetanilid can be recovered from the filtrate unchanged by shaking with chloroform and any picric acid carried along by the solvent is removable by shaking with dilute alkali. On evaporating the chloroform the acetanilid will be found in the residue and should be crystallized and examined for identification. ^m. J. Pharm., 1911, 83, 269. 836 ORGANIC SUBSTANCES If it should happen that caffein were present simultaneously with the anti- pyrin and acetanilid, the same procedure for separating the antipyrin can be employed and the chloroform residue, containing the caffein and acetanilid, is treated exactly as described in the preceding paragraph. Antipyrin, and acetanilid in admixture cannot be satisfactorily separa- rated by crystallization, and when mixed the melting-point is depressed some 40-50°. In connection with a mixture containing antipyrin, the picrate ought to be separated, washed, and its melting-point determined, especially if the sample under investigation is to form the basis of litiga- tion. If the presence of acetanilid is indicated by the carbylamine reaction and caffein is absent, the presence of a phenetidin may be shown by treat- ing the residue with dilute sulphuric acid 1 in 5, transferring to a small Erlenmeyer and heating over the water-bath for an hour or two, noting the odor evolved, and in cases of extreme importance collecting the vapors after running them through a condenser and testing them for acetic and formic acid. The acid solution in the flask is then diluted and treated with bromide-bromate reagent which will give a blue color if a phenetidin were present, and a simultaneous precipitate of anilin tribromide if acetanilid. It is doubtful if one will meet the three common antipyretics combined in one preparation and the employment of acet phenetidin and acetanilid together is rare, but in case one encounters a mixture where the preHminary tests with the residues indicates all of them a pro- cedure along the following lines will enable the worker to draw the proper conclusion. The residue should be treated with dilute sulphuric acid 1 in 5 and heated on the steam-bath as described above, collecting the vapors and testing the distillate for formic, acetic, and other acids. The acid solution is then diluted with water and shaken out with chloroform, which will remove the antipyrin and caffein, and leave the phenetidin and anilin sulphates behind. The antipyrin and caffein can then be sepa- rated by picric acid and their identities established. The acid solution is then warmed to drive off any adhering chloroform, and on cooling is treated with iodin solution, which will precipitate the phenetidin in the form of an iodin compound. On filtering, the anilin is recovered from the filtrate by removing the excess of iodin with sulphite, adding excess of alkali and shaking out with ether. The treatment of acet phenetidin with acid under the conditions above described affects only the radicle attached to the NH group. This fact should be borne in mind when drawing conclusions as to identity. If acetic acid is evolved and the residual solution gives the characteristic reactions, it is practically certain that acetphenetidin is present. If desired the residual solution can be acetylated with acetic anhydride and the original phenetidin reproduced. ANILIDES AND PHENETIDINS 837 For the evolution of methods for the determination of acetanilid in its various mixtures and the simultaneous determination of the accompany- ing ingredients we are indebted to W. O. Emery. His procedures are based on extended researches covering a period of many years, and the details have been perfected from the results of an elaborate system of cooperative work. The methods have appeared in the proceedings of the Association of Official Agricultural Chemists beginning in 1908 and they have been collected and published as a unit for the first time in this work. Acknowledgment and full credit is given him herewith. SEPARATION OF CAFFEIN, ACETANILID AND SODIUM BICARBONATE Caffein Weigh out about 3 grams headache powder on a small (5.5-cm.) tared filter, 1 wash with successive portions of' chloroform to the amount of about 30 mils, collecting the solvent in a 100-mil Erlenmeyer. Distill off chloroform by means of a small flame until only a few mils remain. Add 10 mils dilute sulphuric acid, and then continue the distillation till all the chloroform has gone over, disconnect from condenser, heat gently, first on wire gauze to complete solution, 2 finally on steam- or hot-water bath until contents of flask have evaporated to about 3 to 4 mils. Cool, transfer by washing with water to a separatoiy funnel so that the final volume does not greatly exceed 20 mils. Add four times the volume, or about 80 mils of chloroform, shake for some time vigorously, allow to stand until the chloroform clears perfectly, pass through a small drjr filter into a dry 100-mil Erlenmeyer, distill off the solvent and use dis- tillate for a second extraction, observing the same method of shaking, clearing and filtering as above noted. Distill off chloroform to a small volume, transfer residue to a small tared beaker or crystallizing dish by means of a few mils of chloroform. Allow to evaporate spontaneously or if desired on a steam- or hot-water-bath to dryness, in the latter case partially covering the dish toward end of operation with a watch-glass in order to avoid possible loss from " popping.' Cool in desiccator and weigh as caffein, dry alkaloid. 3 1 In cases of powder mixtures or tablets containing ground celery seed, much coloring matter, cinchona alkaloids, laxative or extractive principles other than acetanilid or phenacetin, it is our practice to shake out the latter from dilute sulphuric acid solution or suspension by means of chloroform. 2 In case the preparation contains ground celery seed or certain oily principles it sometimes happens that the acid solution does not become entirely clear at this point. 3 Should the caffein not be colorless or nearly so, the residue is dissolved in about 10 mils of water, filtered if necessary (in case oily matters are present) through a wet filter, and filtrate acidified with dilute hydrochloric acid, the caffein precipitated with 838 ORGANIC SUBSTANCES Acetanilid First Method. — The acid solution remaining in separator and contain- ing anilin sulphate is run into a 100-mil Erlenmeyer, the filter through which the chloroform passed is washed once with a little water, allowing latter to run into the separator. Rinse the latter thoroughly, adding the aqueous rinsings to acid solutions Now run in slowly and with constant agitation a standard solution of potassium bromide-bromate 1 to a faint but distinct yellow coloration. The number of mils employed, multi- plied by the value of 1 mil in terms of acetanilid, will give the amount of acetanilid present. Second Method. — The acid solution aforesaid is treated with successive small portions of sodium bicarbonate until an excess of this reagent is observed in the bottom of separator. Add 50 mils chloroform and 15 to 20 drops of acetic anhydride, shake for some time vigorously, allow chloro- form to clear then pass through the same filter used for the caffein into a 100-mil Erlenmeyer, and distill off most of the chloroform. Use this distillate for a second shake out, clear, filter, and distill down to a small volume, transferring residue and subsequent chloroform washings to a tared beaker or dish precisely as in the case of caffein. Allow solvent to evaporate spontaneously or by means of a blast or fan, avoiding, how- ever, undue heat. 2 Dry in desiccator over quicklime to constant weight. Verify final weight by means of titration with standard potassium bromide-bromate solution as in the first method. Heat residue with 10 mils dilute sulphuric acid a half-hour on steam- or vapor-bath, cool, add 5 mils water and titrate as directed above. Sodium Bicarbonate The residue left after first treatment with chloroform is weighed when dry and represents very nearly the amount of sodium bicarbonate present. It may be more accurately estimated by titrating with N/10 sulphuric 15 to 20 mils of Wagner's reagent, allowed to stand a half hour, filtered and the pre- cipitate washed with a few mils of same reagent, the filter together with precipitate transferred to separator, decolorized -by means of sodium sulphite and the caffein finally extracted with chloroform. 1 For this purpose the solution is prepared by adding bromin in slight excess to a concentrated aqueous solution of 50 mils caustic potash, the liquid diluted till the sepa- rated salts redissolve, boiled to expel any excess of bromin and finally made up to one liter. This solution is standardized with weighed amounts of acetanilid, or it may be so adjusted by further dilution so that 1 mil is exactly equivalent to 1 centigram, of acetanilid. For purposes of titration 1 to 2 decigrams are heated a half hour on the steam- or water-bath with 10 mils dilute sulphuric acid. 2 Acetanilid suffers appreciable loss when heated above 40°. ANILIDES AND PHENETIDINS 839 acid, using congo red as indicator, or it may be ignited with dilute sul- phuric acid and weighed as sodium sulphate. Calculate results on parts per 100. CAFFEIN, ANTIPYRIN, AND ACETANILID A gross separation of these agents from other materials can usually be effected by a procedure similar to that applied to the more simple caffein-acetanilid mixtures. Owing to the veiy high solubility, how- ever, of antipyrin in aqueous media, a complete extraction therefrom by means of chloroform involves a more protracted treatment with this solvent than is required in the case of caffein. The separation of both caffein and antipyrin from acetanilid is based upon the solubility of the former substances and the insolubility of anilin sulphate, into which the acetanilid must first be converted, in chloroform. Caffein and anti- pyrin are separated one from the other by virtue of their behavior toward mercuric nitrate, the antipyrin yielding under the conditions of the experiment a molecular compound with the mercury salt, practically insoluble in the medium in which the precipitation is effected. After filtration, chloroform extracts from an aliquot of the clear filtrate the caffein, which is weighed directly, while the antipyrin is estimated, after regeneration and recovery from its molecular combination with mer- curic nitrate, by titration with standard alcoholic iodin. Caffein Dissolve an amount of antipyrin-caffein mixture containing not more than 1 gram of the former substance in a 200-mil glass-stoppered flask in about 150 mils saturated aqueous solution of potassium nitrate, heat on the steam-bath nearly to the boiling temperature, then treat, a few drops at a time, with a solution of mercuric nitrate (prepared by dissolving 25 parts red oxide of mercuiy in 60 parts of 25 per cent nitric acid by means of gentle heat, diluting with water to 200 mils then saturating this solu- tion with potassium nitrate), the flask being agitated after each addition in order to clarify the liquid; 10 to 12 mils reagent should suffice to effect complete precipitation. Any undue excess of mercuric nitrate is to be avoided. On standing several hours or until the product has acquired the temperature of the room fill flask to mark with saturated solution of potassium nitrate, mix thoroughly, then filter by the aid of suction, using in this connection if available, a small (4-cm.) perforated plate and the requisite filter. Transfer an aliquot (100 mils) of the filtrate to a sepa- ratory funnel and extract five times with 50-mil portions of chloroform, the solvent from each extraction being run through a small pledget of 840 ORGANIC SUBSTANCES cotton and dry filter into a 200-mil Erlenmeyer. On completion of the third extraction, distill the chloroform down to about 40 mils, using the distillate thus obtained for the two final extractions. Add the chloro- form from the fourth extraction to that remaining from the first three, transfer the whole to a second separator and shake vigorously with 5 mils water, in order to remove traces of potassium nitrate. Run the chloroform through cotton and filter into a second Erlenmeyer, to which is added the solvent, from the fifth or final extraction, after this has been subjected to washing in the second separator above mentioned. Distill the chloroform from the combined extractions down to a small volume, transfer residue to a small tared beaker, evaporate at the ordinary temper- ature or at a moderate heat on the vapor-bath, and weigh the residual caffein. If the various manipulations have been conscientiously carried out, it will be found that the product is veiy nearly pure. In any case it should be dissolved in water, a few drops of HC1 added and the liquid saturated with H2S. Should any quantity of the ant ipyrin-merc uric nitrate compound have been taken up by the chloroform, a faint color- ation or even slight precipitate will result, which may be filtered off in a Gooch, dried and weighed. From the formula: C11H12N2O • Hg(NOs)2, it will be seen that 1 part of HgS would correspond to 2.21 parts of the molecular compound, hence the quantity of the latter, calculated from the amount of mercuric sulphide obtained, subtracted from the crude caffein would yield one-half the true amount of caffein present in the original mixture. Antipyrin The amount of this substance can be determined by difference provided the combined weight of both caffein and antipyrin is known, otherwise the estimation may be carried out as follows : Weigh out on a small (5.5 cm.) filter an amount of the powdered sample equal to or a multiple of the average weight of one tablet, wash with suc- cessive small portions of 95 per cent alcohol, in quantity about 20 to 30 mils sufficient at least to extract all the antipyrin present in the mixture. Collect solvent in a 100-mil Erlenmeyer, add 10 mils of an alcoholic solu- tion of mercuric chloride (5 grams in 100 mils 95 per cent alcohol), then run in a standard solution of pure iodin (1.351 grams resublimed iodin dissolved in 100 mils 95 per cent alcohol, 1 mil of which is either exactly or approximately equivalent to 10 mg. pure antipyrin until a faint yellow T coloration persists. The number of mils required to bring about this result, multiplied by the value of 1-mil in terms of antipyrin will give the quantity of this substance present in the sample under examination. Comments and Suggestions. — If desired the antipyrin can be readily recovered from its compound with mercuric nitrate. To this end collect ANILIDES AND PHENETIDINS 841 all the precipitate on the porous plate by the aid of saturated saltpeter solution, remove to beaker, add 50 mils water, acidify with HC1, then saturate first in the cold, finally in the heat with H2S, filter and wash the HgS thoroughly with hot water, collecting filtrate in a porcelain evaporating dish. Neutralize the free acid with ammonia and evaporate on a steam-bath to about 10 mils. Transfer to a separatory funnel by the aid of water so that the final volume does not exceed 20 mils. Extract five times with 50-mil portions of chloroform, drying, and collecting the solvent in the usual way in an Erlenmeyer. Distill off most of the chloro- form, transfer residue to a tared beaker by means of additional solvent, evaporate on a steam-bath to apparent dryness, cool, and weigh. Dis- solve the antipyrin thus obtained in 95 per cent alcohol, and titrate all or an aliquot with standard alcoholic iodin. ACETANILID AND QUININ SULPHATE The separation of these two substances is based on the fact that the bisulphate of quinin in aqueous-acid solution is practically insoluble in U. S. P. chloroform, while acetanilid under the same conditions is readily taken up by this solvent. The procedure, therefore, resolves itself into the following steps : Ascertain the weight of 20 or more tablets, reduce to a powder and transfer to a glass-stoppered or well-corked flask. Weigh out on a metal scoop, watch-glass, or other convenient object an amount of powdered sample equal to or a multiple of the average weight of one tablet, trans- fer to a separatory funnel (Squibb form), add 50 mils chloroform, 20 mils water and 10 drops dilute sulphuric acid, sufficient at least to insure a slight excess of this reagent in the mixture. Shake for some time vigor- ously, allow to clear, then draw off the solvent through a small pledget of cotton and a small (5.5 cm.) dry filter into a 200-mil Erlenmeyer. Repeat extraction twice, using the same amount of chloroform as in the first operation. Use a fresh pledget of cotton for each withdrawal of solvent, putting the moist cotton after passage of the chloroform into the filter, where with the latter it is allowed to dry spontaneously, or by placing a few moments on the cover of a steam-bath. On completion of the third extraction the separation of the two ingredients in question is practically complete, all the acetanilid being in the chloroform, while the quinin remains in the aqueous-acid solution, with traces also in both cotton and filter. Acetanilid Distill the chloroform from the three extractions by the aid of gentle heat down to about 10 mils, add 10 mils dilute sulphuric acid (1 : 10 by 842 ORGANIC SUBSTANCES volume), continuing the distillation until all the solvent has passed over. Remove to a steam- or vapor-bath and digest for about one hour or until the liquid has evaporated to about two-thirds the original volume. Add 20 mils water, digest thirty minutes longer, add 10 mils cone. HC1, then titrate with a standard solution of potassium-bromide-bromate, sub- stantially as outlined in the method for the estimation of acetaniiid and caffein. Quinin Sulphate Wash filter and cotton used in drying the chloroformic solution of acetaniiid once with 5 mils water, allowing latter to run into the aqueous- acid solution of quinin. Add solid sodium bicarbonate (or aqueous ammonia) in slight excess, then extract with three 50-mil portions of chloroform, washing each portion in rotation with 5 mils water, and passing the solvent after clearing through cotton and a dry filter, exactly as in the extraction of acetaniiid. Distill the chloroform from the several extractions down to about 10 mils then, if it seems desirable to weigh the quinin as such, transfer residue to a small tared beaker by pouring and subsequent washing with chloroform, evaporate to apparent dryness on the steam-bath, heat for an hour at 125° in an air-bath, cool, and weigh. If, as is usually the case in combinations like the one at present under examination, the weight of quinin sulphate is desired, distill the chloro- formic solution of quinin to apparent dryness by means of gentle heat, dissolve residue in 3 to 5 mils neutral alcohol (just sufficient to prevent precipitation by the standard acid) and titrate with N/50 sulphuric acid (using two drops methyl-red solution as indicator) till color changes to faint red. Remove to steam-bath and heat until most of the alcohol has been expelled, the color of the liquid having in the meantime become ^^ellow again. Now add sufficient acid to restore the faint red coloration, note number of mils expended, then multiply same by 8.66 the value of 1 mil N/50 sulphuric acid in mgs. of quinin sulphate (C2oH24N202)2 • H2SO4 • 7H2O, to get the weight of this substance in sample taken. In the event that the quinin as such has first been weighed, the weight should be further checked by titration, substantially as outlined above. Comments and Suggestions. — The composition of many medicinal preparations in pill or tablet form is frequently of such a natuie as to com- pletely inhibit any rational separation of the active organic constituents by means of immiscible solvents in the ordinary separatory funnel, owing to the formation of persistent emulsions even on cautious agitation. To obviate this difficulty various flattened types of separators have been suggested one of which illustrated on page 25, yields gratifying results, a twenty-minute treatment on the rotating table suffices to effect a maxi- mum distribution of the substances involved. Wherever available such ANILIDES AND PHENETIDINS 843 separators will be found highly advantageous in obviating the delay and annoyance occasioned by emulsifying mixtures. Since quinin sulphate readily loses a portion of its water of crystalliz- ation when exposed to dry air, the amount of sulphate found, whether calculated from quinin as weighed or from that determined volumetrically, need not necessarily correspond with the declared amount of this com- modity indicated on the sample under investigation. ACETANILID, QUININ SULPHATE AND MORPHIN SULPHATE As in a mixture of acetanilid and quinin sulphate, so likewise in the present combination, the alkaloidal constituents in aqueous-acid solu- tion are separated from the third by virture of the insolubility of their sulphates in chloroform. The separation of the alkaloids themselves is based on the ability of morphin to yield with an alkaline base a morphinate insoluble in chloroform. The procedure thus resolves itself into the follow- ing particulars. Acetanilid Transfer to a separatory funnel an amount of the powdered sample equal to or a multiple of the average weight of one tablet (the amount of morphin sulphate represented should not be less than J grain), add 20 mils water and 10 drops dilute sulphuric acid, then extract with three 50-mil portions alcohol-free chloroform, the subsequent manipulations being substantially as directed for this ingredient in the combination: Acetanilid and Quinin Sulphate. Quinin Sulphate Wash filter and cotton used in drying the chloroformic solution of acetanilid once with 5 mils water, uniting latter with the aqueous-acid solution and quinin and morphin. To this solution add 4 to 5 mils aqueous sodium hydroxide (5 grams pure NaOH in 50 mils water), then extract with three 50-mil and one 25-mil portions U. S. P. chloroform, transferring latter in rotation to a second separator (Squibb type) containing 5 mils water, wash, and pass the nearly clear chloroform through a pledget of cotton and small filter into a 200-mil Erlenmeyer, from which the solvent is later removed by gentle distillation and the residue titrated, sub- stantially as outlined for quinin in the combination: Acetanilid and Quinin Sulphate. Morphin Sulphate Wash filter and cotton empk^ed in the preceding operation with 5 mils water, which latter together with that portion used to wash the 844 ORGANIC SUBSTANCES chloroformic solution of quinin is united with the aqueous-alkaline solu- tion of sodium morphinate. Now add 0.5 gram ammonium chloride (an amount slightly in excess of that required to free the morphin as well as convert the NaOH into NaCl) and to the resulting ammoniacal solution, add 45 mils U. S. P. chloroform and 5 mils alcohol, then extract and draw off solvent into a second separator containing 5 mils water, wash, allow to clear, then pass chloroform through cotton and filter into a 200-mil Erlenmeyer. Repeat extraction and subsequent washing with one 50- mil, one 40-mil, and one 30-mil, U. S. P. chloroform, finally collecting the solvent from all extractions and distilling from the aforesaid Erlen- meyer down to about 10 mils. Transfer by pouring and washing with additional chloroform to a small tared beaker, evaporate on the steam- bath to dryness, cool, and weigh the residual morphin now appearing as a transparent varnish. To render crystalline, dissolve by warming with 1 mil neutral alcohol, add about the same quantity of water drop by drop, rubbing the glass with a rod to induce crystallization, then evaporate slowly on the steam-bath to dryness. Cool and weigh a second time. Check the weight of morphin thus found by titration with N/50 sulphuric acid, using a drop of methyl-red solution as indicator. To this end dis- solve the morphin in 1 to 2 mils warm neutral alcohol, then after solu- tion is complete add the acid till color changes to faint red. Evaporate most of the alcohol on the steam-bath, and in the event that the color has reverted to yellow add just sufficient acid to restore the faint red coloration. Note volume of acid expended, then multiply the number of mils by 7.53 (the number of mg. morphin sulphate equivalent to 1 mil N/50 sulphuric acid) to ascertain the quantity of morphin sulphate in the sample taken. The amount of anhydrous or of crystallized alkaloid can also be determined from the titration value by use of the proper factor. Comments and Suggestions. — For the purpose in question alcohol- free chloroform may be conveniently prepared by washing the pharma- copeal product several times with water. All cotton used for drying chloroform should first be freed from fatty material or other extractives by thorough washing with this solvent, all of which latter may be regained by distillation. In the various operations involving fixation and subsequent liberation of morphin by means of fixed alkali and ammonium chloride, strict atten- tion should be paid to the matter of adding these reagents, since any undue excess of either might nullify the entire procedure. Any large excess of NaOH would naturally require for its reduction a correspondingly large amount of NH4CI, the latter in turn yielding its pro rata of NEUOH, relative large quantities of which through interaction with NaCl tend to inhibit any permanent liberation of the alkaloid and thus prevent a complete extraction. Furthermore, the presence of relatively large quan- ANILIDES AND PHENETIDINS 845 tities of NH4OH as such operates to a partial retention of morphin in solu- tion, due in part, possibly, to the formation of the hydrochloride of this alkaloid. In spite of all precautions in the matter of excluding impurities from morphin, the amount of this substance as found by weight will usually be greater than that determined volumetrically. In order to insure greater accuracy in volumetric operations with alkaloidal substances as quinin, morphin, etc., the suggestion is made, in all cases where possible, that the strength of the standard acid used be checked by titration against the pure alkaloid under examination. ANALYSIS OF MIXTURES CONTAINING CODEIN, ACETANILID, AND SODIUM SALICYLATE The separation and estimation of these three substances is effected in the following manner: Reduce 20 tablets to a fine powder, then weigh out an amount equal to the average weight of one tablet, transfer to a separatory funnel, add 50 mils chloroform, 10 mils of water, and about 1 mil of dilute sulphuric acid, sufficient to insure acidity in the solution. Shake vigorously, allow to clear, then draw off solvent through a pledget of cotton and dry filter into a second separatory funnel of about 200 to 250-mil capacity. Extract a second and third time, using the same amount of chloroform as before. After each withdrawal of the solvent throw the cotton pledget into the separator and substitute a fresh one in its place. Treat the combined chlcroformic extracts as directed under acetanilid. Codein Wash the filter used to dry the chloroform solution of acetanilid and salicylic acid with 5 mils of water, receiving latter in the separator con- taining the aqueous acid solution of codein. Add solid sodium bicar- bonate in slight excess, then extract by means of vigorous shaking with three 50-mil portions of chloroform. Dry the solvent with cotton and filter as above, collect in 200-mil Erlenmeyer, then distill the liquid by the aid of gentle heat down to about 10 mils. Transfer the residue by pouring and rinsing with fresh chloroform, to a small tared beaker, evapo- rate to apparent dryness on the steam-bath, cool, and weigh as anhydrous codein. Verify by moistening the residue with a little neutral alcohol and titrating with N/50 sulphuric acid, using methyl red (1 drop alcohol soluble) as indicator. Acetanilid To the chloroform solution of acetanilid and salicylic acid add 20 mils of water, and for every 100 mg. of salicylic acid known or believed to 846 ORGANIC SUBSTANCES be present, 1 gram of anhydrous sodium carbonate. Shake vigorously, allow to clear, withdraw the chloroform through cotton, and filter into a 200-mil Erlenmeyer. Extract the aqueous-alkaline solution with two 10-mil portions of chloroform in order to remove traces of acetaniiid taken up temporarily by the water. Distill the united chloroformic extracts by the aid of gentle heat down to about 10 mils. Introduce into flask 10 mils of dilute sulphuric acid (1 : 10 by volume) and digest on the steam-bath until the residue amounts to 3 to 5 mils then add 20 mils of water and 10 mils of concentrated hydrochloric acid. Into this solution run slowly a standard solution of potassium bromide-bromate until a dis- tinct yellow coloration persists. Multiply the number of mils required to complete the formation of tribromanilin by the value of 1 mil in terms of acetaniiid to ascertain the amount of this substance originally present in the sample taken. Sodium Salicylate Transfer the aqueous soda solution containing the salicylic acid from the separator to a 200-mil Erlenmeyer, dilute with water to about 100 mils, heat nearly to boiling, then run in from a burette 25 to 50 mils of N/5 iodin in potassium iodide (or double this quantity of N/10 strength) sufficient to insure an excess of this reagent. Digest the product on the steam-bath for one hour, adding iodin solution from time to time in order to maintain a slight excess. The reddish, insoluble precipitate has the composition (CgH 2 120)2, being identical with the " red substance " first described by Lautemahn : and later used by Bougault 2 in the separation of salicylic from benzoic and cinnamic acids. Remove any excess of iodin by the addition of a few drops of sodium thiosulphate solution, decant liquid through a tared Gooch, care being taken that most of the precipitate remains in the flask. Add 50 mils of boiling water to the latter, digest ten minutes on steam-bath, then pour into Gooch, into which all the reddish precipitate is gradually washed, using for this purpose and subsequent washings about 200 mils of hot water. Dry in air-bath to constant weight. The weight of precipitate multiplied by 0.4658 will give the amount of sodium salicylate originally present in the sample. Should acetphenetidin instead of acetaniiid be employed in the above combination, the procedure need be modified only to this extent, that the chloroform solution of acetphenetidin and salicylic acid, after elimination of the latter substance through treatment with sodium carbonate, is dis- tilled down to about 10 mils and the residue transferred to a small crys- 1 Liebig's Annalen, 1861, 120: 309. 2 J. Pharm. Chim., 1908, 28, 145. ANILIDES AND PHENETIDINS 847 tallizing dish for final evaporation .of solvent and weight of resulting acetphenetidin. In this connection it may not be amiss to state that the quantitative separation of codein, acetanilid, and sodium salicylate could be effected in substantially the following manner: To the mixture in separatory funnel add about 100 mg. of sodium bicarbonate, 10 mils of water and 50 mils of chloroform. Extract three times with this quantity of solvent. The sodium salicylate remaining in the separator is transferred to an Erlenmeyer and treated with iodin solution as above directed, after the extraction of codein and acetanilid is accomplished by shaking out the chloroform solution of these two substances with 10 mils of dilute sul- phuric acid. The acid solution is w r ashed twice thoroughly with about 10 mils of chloroform in order to remove traces of acetanilid taken up temporarily by the aqueous medium. The latter substance, after removal of solvent and subsequent hydrolysis, is titrated with standard bromide- bromate solution, as already described. The aqueous-acid solution of codein is treated with solid sodium bicarbonate in excess, the alkaloid thereupon extracted with chloroform. On removal of solvent by distil- lation and evaporation the codein is first weighed and then titrated with N/50 sulphuric acid. ESTIMATION OF CAFFEIN, ACETANILID, QUININ, AND MORPHIN Weigh out an amount of the powdered sample containing at least one-fifth grain (about 12 mg.) of morphin, transfer to a separatory funnel, adding 20 mils of water, 10 drops of dilute sulphuric acid, and 60 mils of alcohol-free chloroform. Shake vigorously, allow to clear, then draw off through a pledget of cotton and small diy filter into a second separator, in which the solvent is washed with 5 mils water to remove any alkaloidal traces that may have been taken up by the chloroform. The latter is finally passed through a small filter into a 200-mil Erlenmeyer for sub- sequent distillation and treatment in the separation of caffein and acet- anilid. Quinin Repeat the extraction of the aqueous-acid mixture with 50, 40, and 30-mil portions of chloroform, each portion of solvent being treated as directed for the first. The wash water is returned to the first separator, the liquid rendered alkaline by the addition of strong caustic soda in slight excess. We now have the morphin as sodium morphinate insoluble in chloroform, while the quinin is precipitated as a white flocculent mass. Shake out four times with 60-, 50-, 40- and 30-mil portions of alcohol- free chloroform, the solvent from each operation being passed through 848 ORGANIC SUBSTANCES cotton and a dry filter, prior to reception in the Erlenmeyer and distillation from the quinin dissolved therein. Transfer to a small tared beaker by pouring and rinsing with a small quantity of chloroform, evaporate to apparent dryness on the steam-bath, heat amorphous residue one hour at 125° C. in an air-bath, cool, and weigh. Dissolve in alcohol, transfer to a graduated 100-mil flask, fill to mark with water and sufficient alcohol to prevent precipitation of alkaloid; then remove with a pipette an aliquot containing at least one-tenth of the total amount of quinin present and titrate with N/50 sulphuric acid, using as indicator 1 to 2 drops of methyl red (100 mg. dissolved in 100 mils of alcohol). The number of mils required multiplied by 8.66 will give the number of milligrams of quinin sulphate in the aliquot titrated. Morphin In order to recover the morphin from its combination with sodium, add an amount of ammonium chloride slightly in excess of that required to react with the caustic soda previously introduced into the separator and as much common salt as the liquid will dissolve. A slight excess of the latter substance above that necessary to saturate the mixture can do no particular harm other than render the subsequent removal of the chloro- form less quantitative. Extract four times by means of vigorous shaking with 50-, 45-, 40-, and 30-mil portions of Pharmacopoeial chloroform, to the first portion of which are added 5 mils of alcohol prior to extraction. Wash each portion of solvent in a second separator with about 5 mils of water, after extraction but before passing through cotton and filter into a 200-mil Erlenmeyer for distillation. Distill off most of the solvent, transfer residue by pouring and rinsing with fresh chloroform to a tared crystallizing dish, evaporate to apparent dryness on the steam-bath, treat residue with a few drops dilute alcohol should it seem desirable to obtain the morphin in crystalline form, heat again to dryness, cool and weigh. Verify by dissolving the alkaloid in a few mils of warm alcohol and titrating with N/50 sulphuric acid, using as indicator a drop of methyl red solu- tion. The number of mils required multiplied by 7.53 will give the number of milligrams of morphin sulphate present in the original sample. Caffein Distill the chloroformic solution of caffein and acetanilid down to about 10 mils, add 10 mils of dilute sulphuric acid (1 : 10), digest on steam- bath until contents of flask have evaporated to about 5 mils, add 10 mils of water and evapora + e a second time; transfer residue to a separator by pouring and rinsing with water so that the final volume does not exceed 20 mils, then make three extractions with 50-mil portions of chloroform. ANILIDES AND PHENETIDINS 849 After clearing, pass solvent through cotton and dry filter into a 200-mil Erlenmeyer; distill from the combined extractions down to about 10 mils then transfer to a small tared crystallizing dish by pouring and careful rinsing with small quantities of fresh chloroform. Allow to evaporate spontaneously, or at a moderate heat, on a vapor-bath to apparent dry- ness. Remove from heat immediately on the appearance of a crystalline residue. Cool in a desiccator and weigh as anhydrous caffein. Acetanilid Draw off the acid solution remaining in separator into the same Erlen- meyer previously used in effecting the hydrolysis, wash out separator several times with water to insure complete removal of former contents; heat the aqueous-acid solution a short time on steam-bath to expel all traces of chloroform; wash the filter used in the preceding operation to dry the chloroform solution of caffein at once with 5 mils of water, receiving latter in the main solution of anilin sulphate; add 10 mils of concentrated hydrochloric acid, and titrate with a standard potassium bromide-bromate, 1 mil of which is equivalent to 10 mg. of pure acetanilid. The number of mils required to complete the precipitation, multiplied by the value of 1 mil in terms of acetanilid, will give the quantity of this substance originally present in the sample taken. In the event that the quantity of acetanilid present in the tablet is relatively large, as is frequently the case w r hen compared with the morphin content, it is best to titrate only an aliquot of the anilin sulphate solution. METHOD FOR ANALYZING LIQUID HEADACHE MIXTURES. EMERY 1 Alcohol Cool sample to 25° C, at which temperature fill a 25-mil flask to mark, weigh, then transfer to a distilling apparatus, rinsing out the flask several times with water, employing for this purpose a total of 25 mils. Distill into a 50-mil flask (surrounded by ice-water) until the liquid in the dis- tilling flask is reduced to 10 mils. Transfer the somewhat turbid dis- tillate (due to volatile oil) to a separator provided with short delivery tube, rinse out the flask several times with a total of 15 mils water, saturate the combined solution with sodium chloride, shake vigorously for two minutes with 25 mils low boiling (40-60° C.) petroleum ether, then allow to stand fifteen minutes. Draw off entire liquid into a second separator, washing out the first (which still contains undissolved salt) with 5 mils saturated salt solution into the second. Draw off the lower layer into first separator, from which the undissolved salt has in the meantime been 1 U. S. Dept. Agri. Bu. Chem. Bull, 152, p. 256. 850 ORGANIC SUBSTANCES removed, and shake it out as above with a second portion of 25 mils satu- rated solution, transferring resultant mixture to the distillation flask. Distill into a 50-mil flask (cooled in ice-water) nearly to mark, allow temperature to rise to 25° C, fill to mark, and determine the specific gravity at this temperature in a Squibb pyknometer, calculating the per cent of alcohol by "volume from tables. The percentage obtained multi- plied by 2 will give the amount of alcohol in original sample. Caffein-Acetanilid Transfer residual crystalline magma containing the cafTein, acetanilid, and sodium salicylate from distilling flask to a separatory funnel by the aid of successive portions of water (ending with a little chloroform if necessary to remove all traces of acetanilid) so that the final volume of the aqueous solution does not exceed 50 mils. Make five separate extrac- tions by means of vigorous shaking, each time with 70 mils chloroform. Allow solvent to clear after each extraction, pass through small (5.5-cm.) dry filter into a 200-mil Erlenmeyer and distill by the aid of a small flame until about 60 mils have gone over. Use this distillate for each subsequent extraction, making up to 70 mils as found necessary with fresh solvent. After the final extraction and distillation of chloroform, add 10 mils dilute sulphuric acid and evaporate to 4 or 5 mils on steam-bath, transfer the residual acid solution of cafTein and anilin sulphate to a 100-mil gradu- ated flask, fill to mark and determine cafTein and acetanilid in an aliquot of 25 mils as directed in method for Estimation of CafTein, Acetanilid, and Sodium Bicarbonate. Sodium Salicylate (Salicylic Acid) The aqueous solution remaining in separatory funnel and containing the sodium salicylate and glycerin is rendered acid with hydrochloric acid and extracted three separate times by means of vigorous shaking, 70 mils chloroform being employed for each extraction. The solvent, after clearing, is run into a 200-mil Erlenmeyer (containing 10 mils water and 1 gram dry sodium carbonate, sufficient to fix all the salicylic acid present) and distilled over a small flame until most of the chloroform has been expelled. After the final distillation and elimination of all chloro- form, transfer the aqueous soda solution of sodium salicylate to a liter flask, add 10 grams dry sodium carbonate, fill to mark, pipette an aliquot, of 100 mils into a 200-mil Erlenmeyer, heat nearly to boiling, then add about 35 mils N/5 iodin in potassium iodide (or double this quantity of N/10 iodin solution), enough to ensure an excess of iodin. Heat one hour on steam-bath to near the boiling temperature, during which time a violet-red precipitate of tetraiodophenylenquinon, (CeEb^O^, will ANILDIES AND PHENETIDINS 851 appear. Remove excess of iodin by the addition of a few drops of hypo solution, decant liquid off into a tared Gooch crucible, care being taken that most of the precipitate remains in the flask. Add 50 mils boiling water to the iodin compound in flask, digest for ten minutes on steam- bath, then pour into the Gooch, into which the precipitate is gradually washed by means of hot water, using for this purpose about 200 mils. Dry to constant weight in air-bath at 100° C. Multiply weight of pre- cipitate by 0.4658 and the product will be the weight of sodium salicylate in aliquot taken. Report all results in parts per 100. Methyl Acetanilid— Exalgin, C 6 H 5 N(CH3)C2H 3 Methyl acetanilid crystallizes in needles or tablets, melting 100- 101° C. It is soluble in alcohol and boiling water, but only slightly in cold water. When hydrolyzed with acid it gives acetic acid and methyl anilin. The latter substance resembles anilin, but is lighter than water and boils 192°, and a solution of calcium hypochlorite colors it violet and then brown. Acetanilid, and exalgin may be distinguished by the following reaction: about 0.05 gram is treated with 10 drops of hydrochloric acid and boiled for two minutes. The liquid is then cooled, 5 more drops of hydrochloric acid are added, then 1 drop of 1 per cent sodium nitrite solution; after allowing reaction to take place for ten minutes, 1 mil of phenol is added and then gradually enough strong sulphuric acid to give a homogeneous mixture. Of this 0.5 mil is treated with sufficient caustic soda solution; sp. gr. 1.332, to give a clear solution. In the case of exalgin a blue color will be obtained and with acetanilid a yellow tint. Mixtures will naturally vary from yellowish to green. The various details of the test must be rigorously observed. It is used medicinally as an analgesic and antirheumatic. Ethylacetanttid, C 6 H 5 N(C 2 H 5 )C 2 H 3 Ethylacetanilid melts 50° C. Iodacetanilid Acetparaiodanilid, CeHsNHI^HsO). Iodacetanilid melts 181-182° C., soluble in alcohol and glacial acetic acid, insoluble in water. Salifebrin Salifebrin or " salicylanilid " is the name given to the product obtained by the fusion of salicylic acid and acetanilid. 852 ORGANIC SUBSTANCES Formanilid, C 6 H 5 NH(HCO) Prepared from anilin and formic acid similarly to formation of acet- anilid. It forms colorless crystals, melting 46°, soluble in alcohol, water, and glycerin. Its physiological properties are similar to acetanilid, and it has many similar chemical properties as would be expected from its similarity in composition. On heating with dilute sulphuric acid, formic instead of acetic acid is disengaged, thus furnishing important evidence as to its identification. Gallanilid, Gallanol, C 6 H 5 NHCOC 6 H 2 (OH) 3 +2 H 2 Gallanol is the anilid of gallic acid. It is a brownish crystalline sub- stance, melting 205° C, soluble in alcohol, ether, and boiling water, and insoluble in chloroform. It is used as an antiseptic in skin diseases. It combines the properties of an anilid and gallic acid and on hydrolysis may be split up into its components which are then separable and can be identified. Benzanilid, Phenylbenzamide, C 6 H 5 NH(COC6H5) Benzanilid is a white or reddish-white crystalline substance, melting 160-162° C, soluble in alcohol, somewhat in ether but only slightly in water. It is used as an antipyretic. Acettoluides The toluides have already been mentioned on page 833. These bodies have some value as antipyretics and may be substituted for acetanilid in headache mixtures. Their general properties will of course simulate those of acetanilid, but they will yield toluidines on hydrolysis with acids. The ortho and meta compounds have a melting-point which is in close proximity to that of acetanilid. Pyoktanins Rosaniline base is triamidotolyl diphenyl carbinol. /C6H3(CH 3 )NH2 NH 2 C 6 H4C(OH)< X C 6 H4NH 2 Dyes of this type may be considered as derivatives of triphenyl methane. In pararosaniline the amido tolyl group is replaced by the amido phenyl. By use of various homologues of anilin many other compounds are pos- sible and have been prepared. ANILIDES AND PHENETIDINS 853 Pyoktanin Blue This compound consists of the hydrochlorides of penta and hexa- methylpararosaniline and is a violet powder. It is soluble in alcohol, chloroform, water, and glycerin and insoluble in ether. It is a valuable antiseptic and disinfectant and is used in diseases of the mucous membrane and especially in veterinary practice, for it has been found to be a valuable remedy in the foot and mouth disease. It is dispensed in solution in capsules and in pencils, and is sometimes applied combined with mer- curic chloride. I Pyoktanin Yellow Pyoktanin yellow or auramine is imino-tetramethyl diaminodiphenyl- methane hydrochloride. It is a yellow powder somewhat resembling- sulphur and is soluble in alcohol and water. It is employed in skin diseases and in ophthalmic practice. AMINOPHENOLS AND THEIR DERIVATIVES Phenetidins When carbolic acid is added to nitric acid sp. gr. 1.11 in the cold a mix- ture of ortho and para nitrophenols is formed. The former may be sepa- rated by steam distillation, and the latter which is left behind, dissolves in hot water from which it separates on cooling. The meta body is pre- pared by reducing meta-dinitrobenzol, diazotizing with dilute sulphuric and nitrous acid and then boiling, by which process the meta nitrophenol is produced. On reduction, corresponding amino compounds are obtained. The acid character of the phenol is lost in presence of the amino group and the products yield salts only with acids, but they may still be esterified on the hydroxyl and the hydrogen of the amino group is replaceable by radi- cles. These esterified bodies are called anisidins or phenetidins, according to the radicles present, the methoxy group gives the former, and the ethoxy the latter. Then, of course there are the o-,m-, and p-modifications of each. The acetylated phenetidins are the substances of this group which have received the greatest attention by the medical profession and the manufacturing pharmacist. The best known is acetphenetidin or phen- acetin. In preparing them the general procedure consists in esterifying the hydroxyl group of the nitro phenol before reducing the nitro group, and after accomplishing the reduction and separating, the acid radicle is introduced into the amino group. 854 ORGANIC SUBSTANCES A tabulation of the aminophenols and their principal derivatives follows: Ortho Meta Para M.pt. B.pt. M.pt. B.pt. M.pt. B.pt. •OH Aminophenol, C 6 H 4 phenol — > nitrophenol — > ethyoxy nitrophenol— »phenetidin— > acet- phenetidin. But this is one of the possibilities of synthetic chemistry, and is applicable to thousands of other substances. Synthetic chemistry has advanced to such a state that it is possible to work forward and back- ward through numberless compounds, to pass from the aliphatic to the aromatic series, and starting with sufficient quantity of a given substance to eventually arrive at countless others. Antipyrin, salicylic acid, oil of wintergreen, acetylsalicylic acid (aspirin), and many other well-known drugs are just as much derivatives of acetanilid as is acetphenetidin if the argument is valid that by any hook or crook you can obtain one sub- stance from another and call it a derivative of the original. Both the ortho and meta acetphenetidin are known and resemble each other closely in their physical properties. The meta is unimportant. The ortho and para bodies may be differentiated by the wide variance in their melting-points and the difference in the boiling-points of the phene- tidins which result on boiling with dilute hydrochloric acid and which may be separated from the acid liquid by rendering it alkaline and shaking out with ether or chloroform. The para compound is completely changed to acetic acid and p-phenetidin sulphate when digested for an hour with sul- ANILIDES AND PHENETIDINS 857 phuric acid 1 in 5, but the ortho compound requires the action of stronger acid sn. gr. 1.575 for two hours at 90°. If in either case this resulting acid solution be diazotized, and then treated with an ammoniacal solution of naphthol-disulphonic acid, a fine reddish-yellow color appears in the case of the para body, and a cherry-red if the ortho is present. The best methods thus far evolved for the quantitative assay of acet- phenetidin mixtures are the result of the researches of Dr. W. 0. Emery and his associates. METHOD OF ANALYSIS OF MIXTURES CONTAINING CAFFEIN, ACET- PHENETIDIN, ETC. Determine the weight of 20 tablets, powder finely, and weigh out on a small (5.5 cm.) tared filter an amount equal to the average weight of 1 tablet. Wash with successive small portions of chloroform to the amount of 40 to 50 mils sufficient at least to insure complete extraction of all caf- fein and acetphenetidin in the mixture, collecting solvent in a 200-mil Erlenmeyer. Distill off chloroform by means of a small flame until only* a few mils of solvent remain in the flask, using if possible in connection with this and similar operations a small spray trap. Add to the residual liquid 10 mils of dilate sulphuric acid (1 volume concentrated acid to 10 of water) and digest on a steam- or vapor-bath until contents of flask have evaporated to about 5 mils, then add 10 mils of water and continue diges- tion until the residue again amounts to about 5 mils. The quantitative separation of caffein from acetphenetidin depending, as it does, on a com- plete hydrolysis of the latter into acetic acid and phenetidin, even- effort should be exerted to the end that all particles of acetphenetidin which may appear on the sides of the flask be gradually made to disappear in the acid liquid by a gentle rotation of flask during the process of digestion or by the addition of a few drops of alcohol or chloroform. Caffein Cool, pour, and rinse with water into a separatory funnel, so that the final volume does not greatly exceed 20 mils. Extract three times by means of vigorous shaking with thrice the volume of chloroform, in the present instance 60 mils. After clearing, pass through a small pledget of cotton (thrust up into the delivery tube of separator) and a small (5.5 cm.) filter into a 200-mil Erlenmeyer, being careful to recover any caffein which may cling to the apex of the delivery tube and edge of filter by washing with a little fresh chloroform. The pledget of cotton is removed by means of a wire and thrown into the separator on the com- pletion of each extraction, a fresh one being introduced into the delivery tube prior to each subsequent withdrawal of solvent. Distill the chloro- 858 ORGANIC SUBSTANCES form from the combined extractions until the liquid is reduced to about 10 mils then transfer to a small tared beaker or crystallizing dish by pour- ing and careful rinsing with small quantities of chloroform. Allow to evaporate spontaneously or at a moderate heat on a vapor bath to apparent dryness, partially covering the dish with a watch-glass toward the end of the operation in order to avoid possible loss by decrepitation. Remove dish from heat immediately on the appearance of a crystalline residue. Cool in desiccator and weigh as anhydrous cafTein. If caffein residue is impure due to fats, essential oils, coloring matter, etc., purify as directed under caffein-acetanilid mixtures. Acetphenetidin Wash filter used to dry chloroform in the preceding operation once with 5 mils of water, receiving latter in the separatory funnel containing the aqueous acid solution of phenetidin sulphate. Treat with successive small portions of solid sodium bicarbonate until an excess of this reagent, after complete neutralization of the sulphuric acid, persists at the bottom of mixture. Now add 60 mils of chloroform and for every 100 mg. of acetphenetidin known or believed to be present, 5 drops acetic anhydrid; shake for some time vigorously, allow to clear, then pass through cotton and a diy filter, as described for caffein, into a 200-mil Erlenmeyer. Dis- till over 50 mils of chloroform, make up to 60 mils with fresh solvent, and extract again. Distill over as before this time about 60 mils then make the third and final extraction. Distill the chloroform down to about 10 mils, transfer residue by pouring and rinsing with small quantities of sol- vent into a tared 50-mil crystallizing dish, evaporate on steam- or vapor- bath to apparent dryness, finally removing any considerable excess of acetic anhydrid by repeated additions of about 1 mil of fresh chloroform, to which has been added a drop of alcohol. The acetphenetidin will finally appear as a whitish, crystalline mass, having usually a faint acetous odor. The latter will disappear completely on standing some hours in the open, or more quickly on a vacuum desiccator over lime. The residue is weighed at intervals until it suffers no further loss. CODEIN, CAFFEIN, AND ACETPHENETIDIN MIXTURE Codein Weigh out about 0.3500 gram of powdered material (if in pill or tablet form at least 10 of these should be reduced to powder), transfer to a sepa- rator funnel by means of 10 mils very dilute sulphuric acid (or sufficient to render the solution decidedly acid after neutralization of any carbonate that may be present), extract by means of vigorous shaking with 50 mils ANILIDES AND PHENETIDINS 859 of chloroform. After clearing draw off the solvent, allowing it to run through a small (5.5 cm.) filter into a 200-mil Erlenmeyer. Distill off about 50 mils chloroform, using a small Bunsen flame. Extract a second and third time with same amount of solvent as first used. Allow the chloroform from each extraction to run into the Erlenmeyer, then distill off all but about 10 mils. Now add 10 mils dilute sulphuric acid (1 volume concentrated acid to 5 of water) and heat on steam-bath until the chloro- form has disappeared and only about 5 mils of the acid liquid remains, then treat as directed under caffein. Render the acid liquid in separator containing the codein sulphate neutral by the addition of solid sodium bicarbonate, wash out filter used in the proceding operation to clarify the chloroform, once with water, allowing latter to run into the separator, then reextract three separate times with 50 mils chloroform. Collect solvent as above directed in a second 200-mil Erlenmeyer, distilling off most of the liquid by the aid of gentle heat. Transfer residual chloroform to a small beaker or evapo- rating dish, using sufficient fresh chloroform for this purpose, heat gently over steam-bath to dryness, cool, and weigh as anhydrous codein. Caffein and Acetphenetidin The aqueous acid solution containing the caffein and phenetidin sul- phate is transferred to a separatory funnel and treated substantially as directed in the preceding method. SEPARATION OF ACETPHENETIDIN AND SALOL The gross separation of the mixtures from powder, tablets, or pill preparations is most conveniently effected by judicious treatment with chloroform. The separation of the two ingredients from each other can be accomplished in either one or two ways, depending : 1st. On the acid hydrolysis of phenacetin, and salol remaining thereby unchanged, or: 2d. On the alkaline hydrolysis of salol, the phenacetin in such case being unaffected. 1st. Acid Hydrolysis Acetphenetidin If the sample is in pill or tablet form, ascertain the weight of 20 or more, reduce to a fine powder and transfer to a small tube or bottle which can be kept tightly closed with a cork or glass stopper. Weigh out on a small (5.5 cm.) tared filter an amount equal to or a convenient multiple of the average weight of such pill or tablet, wash with successive small 860 ORGANIC SUBSTANCES portions of chloroform, in quantity about 40 to 50 mils, sufficient at least to insure complete extraction of all phenacetin and salol present in the mixture. Collect solvent in a tared 100-mil beaker and evaporate by means of a blast to apparent dryness. During this operation the beaker may be allowed to stand on a warm plate (50-60°) without danger of undue loss of solid substance. Allow to stand twenty-four hours at the ordinary temperature in the open, weigh several times or until the weight becomes practically constant, then transfer the residue, by dissolving in and washing with sufficient chloroform, to a 50-mil lipped Erlenmeyer, evaporate solvent by means of a blast and gentle heat, add 10 mils dilute sulphuric acid (1 : 10) and digest at full bath heat until the liquid is reduced one-half. Add 10 mils water, continue digestion as before, add a second 10-mil portion of water and evaporate to 5 mils. Transfer the residual liquid pouring and washing with about 20 mils water to a separatory funnel of the Squibb type and extract in rotation with 15, 10, and 5 mils chloroform, first washing each portion as obtained with 5 mils water in a second separator to recover traces of phenetidin sulphate possibly taken up by the chloroform, finally rejecting this solvent, since it contains all the salol not carried off with the aqueous and acetous vapors eliminated during the process of digestion. To the aqueous-acid solution of phenetidin sulphate in the first sepa- ratory funnel, — into which also the wash water from the second separator has been poured,— add small portions of sodium bicarbonate until an excess of this reagent, after complete neutralization of sulphuric acid, persists at the bottom of separator. Now add 25 mils chloroform and for every 100 mg. acetphenetidin known or believed to be present 5 drops acetic anhydride, shake for some time vigorously, then pass the nearly clarified solvent into a second separator containing 5 mils water, shake, and receive the chloroform in a 200-mil Erlenmeyer, first passing it through a small (5.5 cm.) dry filter. Of this chloroform, which contains unex- pended acetic anhydride, distill off about 20 mils, return same to the first separator, augment with 5 mils fresh chloroform, and repeat the extrac- tion, washing and filtering as before, then collecting the solvent in the Erlenmeyer and again distilling until 25 mils chloroform are obtained. With this portion, make a third and final extraction, repeating the opera- tions of washing, filtering, and distilling to the point where about 5 mils chloroform remain in the Erlenmeyer. Transfer this chloroformic residue by pouring and washing with sufficient fresh chloroform to a tared 50- mil beaker or crystallizing dish, evaporate on a steam- or vapor-bath to apparent dryness, finally removing any pronounced excess of acetic anhydride by repeated addition of 1-mil portions of fresh chloroform to which a drop of alcohol has been added and subsequent evaporation. Allow the whitish crystalline residue of acetphenetidin to stand some ANILIDES AND PHENETIDINS 861 time in the open, or better, in a vacuum desiccator over lime in order to dispel the last traces of anhydride. Weigh at intervals until constant. Salol To ascertain the quantity of salol present in the sample, subtract the weight of acetphenetidin from the combined weight of the two ingredi- ents determined in the early part of the procedure. Comments and Suggestions. — Tared niters for use in this and similar work may be conveniently prepared as follows: Fold, adjust in a small short-stemmed funnel, moisten and fit carefully so that the entire rim of filter closes snugly on the glass. After drying, keep in balance case or any suitable dust-proof container, and when needed weigh on a small metal support or glass tripod. It is self-evident that all weighings with tared filters should be made as nearly as possible under comparable con- ditions. If, for example, the first weight is taken when the hygrometer indicates a humidity of 50 per cent, the second weighing should if possible be made under approximately similar conditions. This is indispensable when it is desired to estimate the quantity of chloroform-insoluble residue, as in preparations containing sodium bicarbonate, sugar, starch, talc, or other more or less inert material. Experience has shown, however, that a variation in humidity up to 5 per cent in the two weighings would not be productive of material error. Before carrying out an extraction in a separatory funnel, the valve should first be " locked " with a drop of water prior to the introduction of any substance in solution, otherwise losses through capillarity may result. All distillations should be carried out over a wire gauze or asbestos provided with a small opening and subjected to a very gentle heat, the flask being connected with the condenser by means of a small spray trap, if available, similar to the type used in Kjeldahl work. Acetphenetidin being only moderately soluble in hot aqueous media is accordingly somewhat difficult of hydrolysis. In order to insure its complete conversion to phenetidin sulphate, special attention should be directed to the end that any visible particles of crystalline substance on the sides of flask during the early part of digestion should be gradually brought into solution by gently rotating the flask, and if necessary by the occasional addition of a few drops of chloroform. 2d. Alkaline Hydrolysis Phenacetin On a small tared filter as above weigh out an amount of the powdered sample containing not more than 100 mg. salol, exhaust with chloroform 862 ORGANIC SUBSTANCES as for acid hydrolysis, collecting the solvent (not more than 25 mils at one time) in a small (50-mil) Erlenmeyer. Add 10 mils 2.5 per cent sodium hydroxide solution and heat five minutes on a vapor- or steam-bath at the temperature of boiling water. At the end of this period remove and cool immediately to room temperature in running water in order to reduce to a minimum any tendency of the phenacetin to undergo partial hydrolysis. Transfer the liquid to a separatory funnel by pouring and washing with as little water as possible, finally rinsing out the flask with the first 20- mil portion of chloroform used in extraction. Extract the aqueous- alkaline solution with three 20-mil portions of chloroform, washing each portion as obtained consecutively in a second separator with 5 mils water, prior to passing through a small (5.5 cm.) dry filter into a 200-mil Erlen- meyer, from which the combined solvent is distilled down to a residue of about 5 mils. Transfer the latter by pouring and washing with sufficient fresh chloroform to a small tared beaker or crystallizing dish, evaporate the solvent on the steam-bath by the aid of a blast, cool, and weigh at intervals until constant. Salol Transfer both aqueous-alkaline solutions from the separatory funnels to a suitable (500 mil) glass-stoppered bottle, dilute with water to about 200 mils, run in from a burette an excess (about 45 mils N/7) of potassium- bromide-bromate, follow with 10 mils cone, hydrochloric acid, close flask and shake one minute and then at intervals over a period of one-half hour. At the end of this time add 10 mils 15 per cent potassium iodide solution, agitating the closed flask at intervals for fifteen minutes. Titrate the free iodin with standard thiosulphate (preferably N/7), previously adjusted to the standard bromin solution, 1 mil of which is equivalent to 0.002548 gram salol. From the number of cubic centimeters of stand- ard bromin solution expended, calculate the salol on the basis of 12 atoms of bromin to 1 molecule of salol. Comments and Suggestions. — In order to facilitate the work and mini- mize errors due to recharging the burettes N/7 solutions are advocated in order that the volume of the thiosulphate rquired may not exceed the capacity of a 50-mil burette. The thiosulphate solution is standardized against pure iodin. The strength of the bromin solution may be checked if desired by the aid of acetanilid. The reactions involved in the foregoing procedure are: First, hydrolysis of salol to sodium phenolate and salicylate: C 6 H 4 (OH)COOC 6 H5+3NaOH=C6H4(ONa)COONa+C6H 5 DNa+2IfcO ANILIDES AND PHENETIDINS 863 Phenol is attacked by bromin in excess to form symmetrical tri-bromo- phenolbromide : C 6 H 5 OH+4Br 2 = C 6 H 2 Br 3 OBr-f-4HBr while salicylic acid finally yields the same product, the tribromosalicylic acid first formed being very unstable and losing its carboxyl : C 6 H4(OH)COOH+4Br 2 = C 6 H 2 Br 3 OBr-|-4IIBr+C0 2 The tribromophenolbromide thereupon reacts with hydroiodic acid to yield tribromophenol and free iodin : C 6 H 2 Br 3 OBr+2HI = C 6 H 2 Br 3 OH-f-HBr-r-I 2 Accordingly, 12 atoms of bromin are required for every molecule of salol. ACETPHENETIDIN AND QUININ SULPHATE So far as the separation is concerned the method differs in no particular from that outlined for the combination of acetanilid and quinin sulphate. In the estimation, however, the procedure as applied to acetphenetidin is materially shortened, in that the physical properties of this substance permit its being weighed directly. Acetphenetidin Extract with three 50-mil portions of chloroform, washing each portion in rotation in a second separator (Squibb form) with 5 mils water and passing solvent after clearing through a pledget of cotton and small dry filter into a 200-mil Erlenmeyer. Distill the chloroform from the com- bined extractions down to about 10 mils, transfer the residue by pouring and washing with additional chloroform to a small tared crystallizing dish, allow to evaporate spontaneously or at a moderate heat on the steam-bath, cool and weigh at intervals until the loss does not exceed 0.5 mg. Quinin Sulphate Follow directions as given under Acetanilid and Quinin Sulphate. Comments and Suggestions. — In all cases where cotton is used to remove suspended moisture from chloroform as suggested in the fore- going work, the material is inserted in the outlet tube, thus intercepting most of the moisture and any suspended matter that might otherwise clog the filter. Acetphenetidin and acetanilid are not dispensed together, but there is always the possibility that a determination of the antipyretic compounds 864 ORGANIC SUBSTANCES in a mixture of these two antipyretics may become a matter of moment. Dr. Emery has developed a method for determining both acetanilid and acetphenetidin when they occur together and also a quantitative assay of a composite of the three antipyretics acetanilid, antipyrin and acet- phenetidin with caffein: ACETANILID AND ACETPHENETIDIN (PHENACETIN) IN MIXTURES. ACETPHENETIDIN Reagents (a) Purified Iodin. — Dissolve 2 parts of resublimed iodin and 1 of potassium iodid in 1 of water, pour the clear solution into a large volume of water, filter and wash the finely precipitated iodin several times on a porous plate with water. Dry in the air and finally in a desiccator over sulphuric acid where it is kept in a glass-stoppered weighing bottle. (b) Standard Sodium Thiosulphate Solution. — Dissolve 30 grams of crystallized sodium thiosulphate in water and dilute to 1 liter. Stand- ardize this solution against the purified iodin as follows : Weigh out about 0.3 gram of the purified iodin in a small glass capsule (about \ inch high and f inch diameter) provided with a closely fitting glass cap or stopper, and place the capsule in a 200-mil Erlenmeyer flask containing 0.5 gram of potassium iodid dissolved in 10 mils of water. After complete solu- tion, titrate with the sodium thiosulphate solution, using 1 or 2 drops of starch solution as an indicator. (c) Standard Iodin Solution. — Dissolve 40 grams of potassium iodid in the least possible quantity of water, add 30 grams of the purified iodin and, after solution, dilute to 1 liter. Standardize 25 mils of this solu- tion against the standard sodium thiosulphate solution. Determination. — (1) Place 0.2 gram of the acetphenetidin-acetanilid mixture in a 50-mil lipped Erlenmeyer flask, add 2 mils of glacial acetic acid, heat gently over a wire gauze to complete solution, and dilute with 40 mils of water, previousy warmed to 70° C. Transfer the clear liquid with two 10-mil portions of warm (40° C.) water to a glass-stoppered, 100-mil graduated flask containing 25 mils of the standard iodin solution warmed to 40° C. Stopper, mix thoroughly, then add 3 mils of concentrated hydrochloric acid, continue shaking until crystallization begins and then set aside to cool. If the ratio of acetphenetidin to acetanilid is equal to or greater than unity, crystalline scales will form almost immmediately on the addition of acid. As the proportion of acetanilid increases, however, the periodide tends to remain in the liquid state. In such cases, gentle agitation or rotation of the flask in water, warmed not to exceed 40° C, hastens the formation of crystals. When the contents of the flask are at ANILIDES AND PHENETIDINS 865 room temperature, fill with water to within 2 to 3 mils of the mark, mix thoroughly, and allow to stand overnight. Fill to the mark with water, mix thoroughly, allow to stand thirty minutes, filter through a 5.5 cm. dry, closely fitting filter into a 50-mil graduated flask, rejecting, however, about 15 mils of the first runnings, but reserving them for the recovery of the acetanilid. Transfer the 50-mil aliquot to a 200-mil Erlenmeyer flask and titrate with the standard sodium thio sulphate solution. Cal- culate the amount of acetphenetidin from the following formula : Acetphenetidin = 1(0.0899 XN) 0.0889 = the quantity of acetphenetidin contained in 1 mil of a normal solution of this substance; N = the normality of the standard sodium thiosulphate solution employed; and I = the number of mils of the standard sodium thiosulphate solution corresponding to the iodin combined with the acetphenetidin. The formula of the precipitated periodide, which constitutes the basis for the above determination, is (C 2 H 5 • C 6 HiNH • COCHs^HI • I4. (2) The gravimetric determination of acetphenetidin may, if desired, be effected as follows : Filter off the periodide, preferably by suction, wash with 10-15 mils of the standard iodin solution, then transfer together with the filter to a separatory funnel, using not over 50 mils of water. Remove both free and added iodin with a few small crystals of sodium sulphite and extract the liquid with three 50-mil portions of chloroform, washing each portion subsequently into a second separatory funnel with 5 mils of water. After washing and clearing, filter the chloroform solution through a dry 5.5-cm. filter into a 200-mil Erlenmeyer flask, distill off most of the chloroform, transfer the residual solution (5 to 10 mils), by means of a little chloroform, to a small, tared beaker or crystallizing dish, evaporate to dryness on a steam-bath, cool, and weigh. For the identification of acetphenetidin, either alone or in admixture with acetanilid, the following test will be found of value: To 1 to 2 mg. of the sample in a test-tube add a drop of acetic acid and 0.5 mil of N/10 iodin, warm the mixture to about 40° C, then add a drop of concentrated hydrochloric acid. If acetphenetidin alone is present, its periodide sepa- rates almost immediately in the form of reddish-brown leaflets or needle- like crystals. If the sample consists largely of acetanilid, the separation takes place on cooling and shaking the liquid. In the globules, which, on vigorous shaking, gradually become crystalline, this test is so delicate that as little as 0.5 mg. of acetphenetidin may, if alone, be detected in the form of its characteristic periodide. 866 ORGANIC SUBSTANCES Acetanilid (1) If the combined weight of the acetphenetidin-acetanilid mix- ture is known, determine that of the latter ingredient by difference; or, (2) Determine it directly from a second aliquot of the filtrate from the acetphenetidin in the foregoing as follows: Pipette 25 to 30 mils of the clear liquid into a separatory funnel, decolorize with solid sodium sulphite and solid sodium bicarbonate in slight excess, add 1 or 2 drops of acetic anhydride, then extract with three 60-mil portions of chloroform, passing the chloroform solution, when cleared, through a small, dry filter into a 200-mil Erlenmeyer flask, and distill the chloroform, by the aid of gentle heat, to about 20 mils. Add 10 mils of sulphuric acid (1 : 10) and digest on a steam-bath until the resi- due has been reduced one-half, add 20 mils of water and continue the digestion for an hour: then add a second 20-mil portion of water and 10 mils of concentrated hydrochloric acid, titrate very slowly, drop by drop, with the standard bromide-bromate solution, until a faint yellow color remains. While adding this reagent, rotate the flask sufficiently to agglom- erate the precipitated tribromanilin. Calculate the amount of acet- anilid present. If the preparation contains caffein or antipyrin or both in addition to acetanilid and acetphenetidin, proceed as follows: (1) Digest the mixture by heating with dilute sulphuric acid to convert acetphenetidin and acetanilid into phenetidin and anilin sulphates, respectively; (2) Separate the caffein and antipyrin by extraction with chloroform; (3) Re-form acetphenetidin and acetanilid by treating the solution of the corresponding sulphates with solid sodium bicarbonate in slight excess, then add a few drops of acetic anhydride and extract with chloroform ; (4) Weigh the residue of acetanilid and acetphenetidin, then dissolve in glacial acetic acid and pour into standard iodin solution using precautions given above for precipitating the periodide of acetphenetidin. Titrate an aliquot and calculate the acetphenetidin; (5) Determine the acetanilid by difference or directly in an aliquot of the clear liquid by destroying the excess of iodin, extracting with chloroform in the presence of acetic anhydride, converting the residue to anilin sulphate by digestion with dilute sulphuric acid, and finally titrating the anilin sulphate with bromide- bromate reagent; (6) The caffein and antipyrin can be separated from each other by precipitation of the latter by picric acid. ANILIDES AND PHENETIDINS 867 Methyl Acetphenetidin /OC2H5 C 6 H4< x N(CH 3 )COCH 3 melts 40° C, distills 300°, and crystallizes on standing. It is moderately- soluble in water, soluble in alcohol, ether, benzol, and chloroform, and is used as an hyponotic, Methoxy acetphenetidin, Kryofine. Kryofine is a condensation product of paraphenetidin and methyl- gly colic acid. /OC2H5 CeH4\ \NHCOCH3OCH3 It is a white crystalline substance, melting 98°, slightly soluble in water, readily in alcohol. Amino Acetphenetidin. Phenocoll or Phenamine ,OC 2 H 5 CgHk ^NHCOCH 2 NH 2 Phenocoll is prepared by the action of chloracetyl chloride on phene- tidin and treating the product of the reaction with ammonia. It is a much stronger base than acetphenetidin and forms salts with acids. The free base (phenocoll) obtained by precipitating the aqueous solu- tion with fixed alkalies or their carbonates forms white, matted needles, containing one molecule of water. In its hydrated condition it melts at 95° C. while the anhydrous base melts at 100.5° C. It is stable and not chemically affected by acids or alkalies unless subjected to prolonged boiling with these reagents, by which phenocoll is split into phenetidin and glycocoll. Phenocoll is usually dispensed or sold in the form of the hydrochloride. Phenocoll salicylate or salocoll is prepared by neutralizing a hot aqueous solution of salicylic acid with phenocoll and cooling the solution. It forms fine, white crystalline needles, having a sweetish taste, spar- ingly soluble in cold water (1 : 200), readily soluble in hot water. It gives a violet reaction with ferric chloride. It is incompatible with soluble hydroxides and carbonates and with bodies which are incompatible with the salicylates in general. It is used in rheumatism, gout, chorea, pleuritis, and fevers, especially in influenza. 868 ORGANIC SUBSTANCES Iodophenin is a product purporting to be a periodide of acetphenet- idin. It is a brownish-black crystalline substance, melting 130-131°, and soluble in alcohol and water. It is employed chiefly for its anti- septic value, though it is claimed that it possesses some value as an internal remedy in articular rheumatism. Thymacetin ,OC 2 H5 / /CH3 Thvmacetin is credited with the composition CeH 2 ^ ( X C 3 H 7 NHCOCH3 It is a white crystalline powder, melting 136°, soluble in alcohol and ether and slightly in water. Phesin Phesin is the name given to a sodium sulpho product prepared from acetphenetidin. It is soluble in water and is used as an antipyretic. The drug trade has been flooded with a quantity of phenetidin deriva- tives closely allied to acetphenetidin. They differ from acetphenetidin in that some other acid radicle is substituted for the acetyl group, or the phenetidin complex is esterified with carbonic acid and another base. Formyl Phenetidin ,OC 2 H 5 C6H4X \NHCOH Formylphenetidin forms colorless crystals, melting 60°, soluble in alcohol and ether but insoluble in water. It is devoid of antipyretic properties, but has been suggested as an antidote for strychnin poisoning and as an antiseptic. Lactophenin Lactophenin is lactylparaphenetidin, CeKU • OC2H5 • NH(CH 3 ■ CHOH • CO) Lactophenin occurs as a white crystalline, odorless powder, of slightly bitter taste and neutral reaction. It melts at 117.5° to 118° C. It is rather difficultly soluble in cold water (1 : 330), and is soluble in 55 parts of boiling water. It is soluble in 8.5 parts of alcohol and is not precipi- ANILIDES AND PHENETIDINS 869 tated from this solution by water. In ether and petroleum ether it is difficultly soluble. On boiling 0.2 gram of lactophenin with 2 mils hydrochloric acid for one minute, then diluting the solution with 20 mils water and filtering when cold the filtrate will become colored a ruby red on the addition of chromic acid solution. On dissolving 0.1 gram lactophenin in 10 mils hot water, and filtering when cold, the filtrate on the addition of bromin water, should develop a decided turbidity which disappears on the addition of much water. Triphenin— Propionyl-phenetidin, C 6 H4(OC2H5)NH(CH 3 CH 2 CO) is a derivative of paraphenetidin, differing from acetphenetidin in that the acetic acid residue has been replaced by the propanoic acid residue, (CH3CH2CO). It is a white, shining crystalline powder, melting at 120° C, odorless and faintly bitter. It is practically insoluble in water, requiring 2000 parts, but soluble in alcohol and ether. In general it responds to the tests for acetphenetidin. From this it may be distinguished by its melting-point, and by identifying the pro- panoic acid evolved when heated with 50 per cent sulphuric acid. Triphenin is antipyretic, analgesic, and hypnotic. Salicylparaphenetidin. Malakin .OC2H5 CeH4< ^NHCOC 6 H 4 OH Malakin forms bright-yellow needles, melting 92° C, soluble in hot alcohol and alkali carbonates, insoluble in water. It is antipyretic, analgesic, and teniacidal, and is used in the expulsion of tapeworm. Phenetidin Salicylacetate or Acetosalicylate, Phenosal /OC2H5 C6H40+2K 2 C0 3 +2C0 2 As(CH3) 2 X It is an intensely evil-smelling liquid, boiling 150° C, extremely poisonous, 873 874 ORGANIC SUBSTANCES and unites with acids forming salts, As(CH 3 )2Cl. On oxidation with mer- curic oxide cacodylic acid is produced. As(CH 3 ) 2 v >0+2HgO+H 2 = 2(CH 3 ) 2 AsO • OH+2Hg As(CH 3 ) 2 X Cacodylic acid is a crystalline, odorless, deliquescent substance, soluble in water and alcohol, and melts 200° C. It is monobasic, acid to litmus and phenolphthalein, and neutral to methyl orange. If 1 mil of the solu- tion of the acid is treated with 10 mils of a solution of hypophosphorous acid containing hydrochloric acid, stoppered and allowed to stand, the odor of cacodyl will be noted on uncorking the flask. The cacodyl complex is decomposed with considerable difficulty. If cacodylic acid or its salts are fused with alkali and afterward dissolved in water, acidulated, and subjected" to the action of hydrogen sulphide, there is considerable precipitation of the sulphide, but the odor of cacodyl is apparent. Similar conditions will be noted in the Marsh test, the mirror forms but there is an odor of cacodyl evolved. The cacodylates are not of great importance medicinally at the present time. They may be used in cases where an arsenic tonic is indicated, such as malaria, diabetes, anemia, chlorosis, etc., and in veterinary practice the sodium salt has been found useful as a remedy for " loco v poisoning. A number of salts have been prepared, including the sodium, potassium, lithium, calcium, magnesium, iron, manganese, silver, and mercury. Some of these, especially with the heavier metals, are of doubtful composi- tion; e.g., the iron salt may be simply a mixture of iron oxide and the acid. The sodium salt is the best known commercial compound. It may contain varying amounts of water, but as marketed it usually contains three molecules. It is a white powder, very soluble in water, forming needle-shaped crys- tals, hygroscopic, but otherwise of marked stability. The aqueous solution is alkaline toward litmus, but nearly neutral toward phenolphthalein. On addition of silver nitrate to a solution of 1 gram of sodium cacodylate in 20 mils of water, a white precipitate is formed which is solu- ble in nitric acid and in ammonia water. If to 1 mil of a 1 per cent solu- tion of sodium cacodylate 10 mils of hypophosphorous acid are added and put aside for one hour in a closed container, a disgusting odor of cacodyl is apparent. If calcium chloride solution is added to a solution of sodium cacody- late (1 : 20) no precipitate will be produced in the cold nor on warming (distinction from sodium menomethyl arsenate). Estimation. — A weighed quantity (approximately 1 gram) is dissolved in 25 mils of water, one drop of methyl orange added, and then normal ORGANIC ARSENIC COMPOUNDS 875 hydrochloric acid added until a faint pink color appears; 1 mil normal hydrochloric acid = 0.2125 gram of sodium cacodylate. If to the finished titration phenolphthalein is added, a volume of normal potassium hydroxide equal to the volume of normal acid used should be required to produce a red color; (CE^AsC-OH being a monobasic acid toward phenol- phthalein. The monomethyl acid, CHsAsO(OH)2, or arsonic acid, is known in the form of its sodium salt, CH3AsO(ONa)2, called Arrhenal or New Cacodyle, which is prepared by the interaction of methyl iodide and sodium arsenate in the presence of an excess of alkali. Arrhenal is soluble about 1 in 1 in water, only slightly in alcohol 90 per cent. A solution of the salt (strongly acidified) with hydrogen sul- phide gives a precipitate of mono- and disulphide of methyl-arsine. Arrhenal solutions do not precipitate with baryta water (sodium cacody- late does), nor with magnesia mixtures (nor does sodium cacodylate), nor by cold solution of calcium chloride (nor does sodium cacodylate), but are precipitated by nitrates of silver (white silky precipitate; sodium cacodylate none) and mercury (also sodium cacodylate; both yellow, arrhenal the darker of the two). Mercuric chloride gives reddish-yellow precipitate with arrhenal, and a white precipitate with sodium cacody- late. Sodium p-aminophenylarsonate gives a white precipitate with these reagents in every case. Arrhenal may be estimated by dissolving about 0.2 gram in 1 to 2 mils of water and adding 15 to 20 mils of hydrochloric and hypophosphorous acid mixture. After twelve hours dilute with 15 to 20 mils of water and filter, washing the residue with water. To the filter and its contents add a known excess of N/10 iodin solution, shake well, and titrate excess with sodium thio sulphate. • CH 3 As+4I+3H20 = CH 3 AsO(OH)2+4HI The black body CH3AS is quantitatively produced from 1 molecule CH3 AsO • (ONa)2, therefore 4 atoms of iodin = 1 molecule arrhenal. Bougault suggested this reagent for testing for traces of arsenic in glycerin (arsenite or arsenate) and for cacodylate. For the latter it is exceed- ingly delicate. To prepare the test, dissolve 20 grams sodium hypophosphite in 20 mils water and add 200 mils hydrochloric acid (1.17 sp. gr.). Sodium chloride is thrown out and removed. To apply the test, 5 mils glycerin is mixed with 10 mils of the reagent. Place in water-bath — brown deposit. This methylarsine, CH3AS, is also obtainable by action of sodium hypophosphite and sulphuric acid on sodium cacodylate, 2H3PO2 + AsCH 3 0(OH) = 2H3PO3 +CH 3 As +H 2 0, as a yellow oil insoluble in water, with strong garlic odor. 876 ORGANIC SUBSTANCES Arsanilic Acid, C 6 H 4 (NH 2 )(As(OH) 2 ) Arsanilic acid is prepared by condensing anilin and arsenic acid. The sodium salt, C 6 H4(NH 2 )(AsO-OH-ONa), crystallizes with 5 mole- cules of water, 3 of which are lost by efflorescence. The arsenic content of the commercial article varies somewhat and the product is known by several names, Arsanin, Atoxyl, Soamin and Sodium arsanilate, all of which may differ slightly in their amounts of arsenic. An acid solution of sodium arsanilate is not affected by hydrogen sulphide in the cold, but precipitation is complete when the solution is warmed. Iodin is liberated when a solution is treated with hydro- chloric acid and potassium iodide, and the resulting solution is precipi- tated by hydrogen sulphide. Mineral acids cause a precipitation of white arsanilic acid, and silver nitrate throws out a white precipitate. An aqueous solution when treated with hydrochloric acid and potassium nitrate, gives a deep red color with a solution of beta-naphthol in sodium hydroxide. Solutions of sodium arsanilate give a yellow precipitate or a yellow color with calcium hypochlorite and a blue color with the same reagent in the presence of phenol. With reducing agents such as zinc and sul- phuric acid in the cold or stannous chloride or hypophosphorous acid in strong hydrochloric acid on warming, a yellow precipitate is obtained. On conversion to arsendiazo benzene by adding a few drops of 0.5 per cent solution of sodium nitrite and a little sulphuric acid, the solution will give a carmine-red color with acetaldehyde, followed by a few drops of potassium hydroxide, and with an excess of alkali the color changes to yellow. Arsacetin, C 6 H4(NHCH 3 CO) (AsO • OH • ONa) +4H 2 Arsacetin is the sodium salt of a derivative of arsanilic acid. It is a white, crystalline substance, odorless, tasteless, and fairly soluble in water. The aqueous solution gives a white precipitate with silver nitrate. If a mixture of 0.1 gram arsacetin, 0.5 gram dry sodium carbonate, and 0.5 gram potassium nitrate are melted in a porcelain crucible, the white mass dissolved in 10 mils water and the solution neutralized with dilute nitric acid, a portion of the liquid yields a white crystalline pre- cipitate on addition of an equal volume of magnesia mixture. A further portion of the neutral liquid furnishes a brown precipitate, soluble in ammonia and also in nitric acid, on addition of a few drops of silver nitrate solution. If 0.2 gram arsacetin is heated with 5 mils alcohol and 5 mils sulphuric acid, the odor of acetic ether is developed. ORGANIC ARSENIC COMPOUNDS 877 The aqueous solution of arsacetin (1 : 10) should be clear and color- less, possess at most a faintly acid reaction, and after addition of 5 mils dilute hydrochloric acid the liquid should not be altered by freshly pre- pared hydrogen sulphide solution. If 0.1 gram arsacetin is dissolved in 20 mils water, 1 mil dilute hydro- chloric acid and 2 drops sodium nitrite solution added and filtered, an alkaline beta-naphthol solution should produce no red coloration in the nitrate. An aqueous solution (1 : 20) to which 20 mils magnesia mix- ture is added should afford no turbidity or precipitate within two hours. Five-tenths gram powdered arsacetin, after heating for four hours at 110-120° C, should show a loss in weight of about 20 per cent. In order to determine the arsenic in atoxyl and arsacetin Rupp and Lehmann 1 heat 0.2 gram of the substance with 10 mils of concentrated sulphuric acid to 70°, and then 1 gram of potassium permanganate is added in small portions with agitation, followed by 5-10 mils hydrogen peroxide until the solution is clear. It is then diluted with 20 mils of water, boiled ten to fifteen minutes and diluted with 50 mils water. After cooling 2 grams of potassium iodide are added and after standing one hour the liberated iodin is titrated with N/10 thiosulphate. ARSENOPHENOL-AMINES These bodies contain two atoms of arsenic believed to be coupled together by a double linkage, the arsenobenzene, CeH 5 • As = AsCgHs, comparable with azobenzene, C6H5N = NCeH5. Arsenphenol-Amine Hydrochloride. Salvarsan. Arsphenamine This interesting body, originally exploited as Erlich's " 606," is 3- diamino-4-dihydroxy-l arsenobenzene hydrochloride HC1NH 2 • OH • CeHsAs = AsC 6 H 3 • OH • NH 2 • HCL+2H 2 The commercial product contains 29.5 to 31.57 per cent arsenic. It is a yellow, crystalline, hygroscopic powder, very unstable in air. It is readily soluble in water, yielding a solution with an acid reaction. The addition of sodium hydroxide solution to an aqueous solution in the ratio of two molecules of sodium hydroxide to one of salvarsan, precipitates the free base (NH 2 • OH • CeHs As : As • C 6 H 3 • OH • NH 2 ) . On the addi- tion of an aqueous solution of sodium carbonate to an aqueous solution of salvarsan, a precipitate is produced which is insoluble in an excess of the reagent. When heated with an alkaline solution of potassium permanganate the permanganate solution is reduced and ammonia given off. 1 Apoth. Zeit., 1911,26,200. 878 ORGANIC SUBSTANCES The addition of ferric chloride solution to an aqueous solution of salvarsan produces a brownish-violet color, which gradually changes to a dark red; finally the liquid becomes turbid. Silver nitrate solution added to an aqueous solution of salvarsan acidi- fied with dilute nitric acid yields a dark-yellow precipitate which rapidly becomes black. The addition of concentrated nitric acid to an aqueous solution pro- duces a yellowish-white precipitate. On further addition of the acid the precipitate redissolves and the solution becomes dark red. Salvarsan gives a green color with nickel salts, pink with cobalt, blue with copper, and a yellow precipitate with picric acid. Neosalvarsan — Neoarsphenamine Neosalvarsan is a mixture of sodium 3-diamino-4-dihydroxy-l-arseno- benzene-methanal-sulphoxylate, NH2 • OH • C6H3 -As : As • C6H3 • OH • NH(CH20)OSNa, with inert inorganic salts. The arsenic content of three parts of neosalvarsan is approximately equal to that of 2 parts of salvarsan. It is an orange-yellow powder possessing a peculiar odor. It is very unstable in the air. It is readily soluble in water, yielding a yellow solu- tion which is neutral toward litmus. Upon standing the aqueous solu- tion becomes dark brown, forming a brown precipitate. A freshly prepared aqueous solution (1 in 100) yields a precipitate on the addition of mineral acids, a brown color and black precipitate with silver nitrate, and with ferric chloride a violet color should be produced, which soon changes to a dark red. If to 10 mils of the aqueous solution 5 mils of diluted hydrochloric acid are added and the mixture heated, sulphur dioxide will be evolved. If to 10 mils of the aqueous solution 5 mils of diluted hydrochloric acid are added, the precipitate collected on a filter and treated with zinc dust and warmed with diluted hydrochloric acid in a test-tube, and if paper moistened with a 5 per cent cadmium chloride solution is held in the mouth of the tube, the paper should be stained yellow within a few minutes (distinction from salvarsan). If to 10 mils of the aqueous solution 5 mils of diluted hydrochloric acid are added, the precipitate removed by filtration, 2 mils of barium chloride test solution added to the filtrate, the mixture allowed to stand for twelve hours, the precipitate of barium sulphate removed by filtration, 5 mils of nitric acid added to the filtrate, the mixture boiled and evapo- rated to dryness, the residue should not be completely soluble in 50 mils of hot water slightly acidified with hydrochloric acid. These remedies are usually dispensed in sealed tubes containing vary- ing quantities or dosages. ORGANIC ARSENIC COMPOUNDS 879 Lehmann x recommends the following method for estimating the arsenic in salvarsan and neosalvarsan : 0.2 gram is weighed into a 200-mil glass- stoppered flask of Erlenmeyer shape (iodin-number flask), 1 gram potas- sium permanganate added, 5 mils dilute sulphuric acid and the mixture agitated repeatedly over a period of ten minutes. Ten mils of concen- trated sulphuric acid are slowly added, rotating the flask meanwhile, followed by 5 to 10 mils hydrogen peroxide solution added drop by drop until the manganese precipitate disappears and a clear solution results. Twenty-five mils of water are now added and the solution boiled for ten minutes, 2 then diluted cautiously with 50 mils water. After cooling 2.5 grams of potassium iodide are added and the flask stoppered and allowed to stand one hour, the free iodin being titrated at the end of that time with N/10 sodium thiosulphate. One mil = .003748 gram arsenic. GRAVIMETRIC DETERMINATION OF ARSENIC IN SALVARSAN Meyers and DuMez 3 obtained results with this method which closely parallel those obtained with Lehmann's procedure. Weigh out accurately about 0.2 gram of the product and transfer it to a Kjeldahl flask of 300 mils' capacity. Add 1.5 grams of a mixture of equal parts of sodium nitrate and potassium nitrate, 200 mils of dis- tilled water and 5 mils concentrated sulphuric acid. Heat the mixture slowly under a hood to allow the escape of the nitric acid fumes. Add a small quantity of concentrated or fuming nitric acid from time to time, until oxidation is completed, which is generally indicated by the disap- pearance of the yellow color. 4 Continue the digestion until the volume of the liquid has been reduced to about 15 mils, 5 cool, add 100 mils of dis- tilled water, and again concentrate to about 15 mils in order to remove the last traces of nitric acid. If the product has been completely oxidized and all traces of nitric acid have been removed, the liquid will be water- clear at this point. After cooling, cautiously neutralize the liquid with strong ammonia water and transfer it to a 300-mil beaker, using a small quantity of distilled water for rinsing the flask. To the solution, which will now contain all of the arsenic in the form of arsenate, add 10 to 20 mils of N/2 ammonium chloride solution for every 1 Apoth. Zeit., 27, 545. 2 Experience has shown that ten minutes' boiling is not sufficient to remove all of the peroxide. Myers and DuMez recommend that after boiling, the last traces of peroxide be removed by the addition of a drop or two of permanganate solution (1 per cent) and the resulting pink color removed with a slight excess of oxalic acid solution. 3 Public Health Reports, 1918, 1003. 4 Sometimes the liquid may still have a pale yellow tint. 5 Concentration should be effected in such a manner that the formation of sulphuric acid fumes in large quantities will be avoided. 880 ORGANIC SUBSTANCES 50 mils of the liquid, then 20 mils of magnesia mixture, drop by drop, with constant stirring. Finally add an amount of strong ammonia water, equal to one-third the volume of the liquid, and 2 mils of alcohol. After allowing the mixture to stand for twelve hours, collect the precipitate, with the aid of a suction pump, in a Gooch crucible, which has been pre- pared as follows: Cover the bottom of the crucible with a thin layer of asbestos, which has previously been washed with ammonia water (2.5 per cent), and dry in an oven at 110° C. Remove the crucible from the oven and place it in a larger porcelain crucible, fitted with an asbestos ring so that the sides and bottom of the two will not touch, put on the cover and heat slowly over an open flame until there is a light-red glow on the outer crucible. Remove the Gooch crucible, cool in a desiccator and weigh. After the precipitate has been collected, dry the crucible as described above, but add a crystal of ammonuim nitrate before heating over the open flame. Finally cool the crucible and weigh. The weight of the precipitate multiplied by 0.48275 represents the amount of arsenic present in the sample taken for analysis, Salvarsan in Forensic Testing Comparatively large amounts of arsenic can be introduced into the body in the form of salvarsan without any symptoms of arsenical poisoning, and it is of importance to distinguish between arsenic in this form and ordinary inorganic arsenic in cases of suspected arsenical poisoning. Positive arsenic reactions are given with the Reinsch, Marsh, and Gutzeit tests. Penicillium glaucum gives the garlic odor, but Bettendorf's test is negative and hydrogen sulphide gives no precipitate. Ferric chloride gives an intense greenish red, auric chloride deep red momentarily; pla- tinic chloride is gradually reduced in the cold, Nessler's reagent is reduced immediately, and phosphomolybdic acid gives an intense blue. Alpha- naphthylamine gives a deep red to violet dye, and the test may be applied directly to urine. Salvarsan may be recovered unchanged from tissue by extraction with alcohol acidified with hydrochloric acid. Silver chloride, bromide, and iodide, when freshly prepared, dissolve in solutions of arsenobenzene hydrochloride. A solution of silver bromide in potassium cyanide is added drop by drop to a solution of the arsenic compound until a permanent precipitate is obtained, which is then redis- solved by the addition of hydrochloric acid drop by drop. From the solu- tion thus obtained sulphuric acid precipitates the arseno-benzene silver compound in the form of an insoluble sulphate, which after being washed ORGANIC ARSENIC COMPOUNDS 881 free from the last traces of potassium chloride and cyanide, forms an orange to brown powder according to the quantity of silver present. It dissolves in water containing a small quantity of sodium carbonate. The chlorine compounds possess the least and the bromin the most anti- septic power and therapeutic value. Dimethylaminotetraminoarsenob enzene CH3 CH3 I I NH NH NH 2 -/ V-NH2 NH 2 — ( V-NH This is a new substance, yellowish green in color, which darkens in the air. It is soluble in acetone and acetic acid but only with difficulty in alcohol and insoluble in water. Arsenoferratin. Sodium Arsenoferrialbuminate Arsenoferratin is an arsenic iron albumin compound, obtained by introducing the element arsenic into the molecules of ferrialbuminic acid. It contains iron in the ferric state equivalent to 6 per cent metallic iron and arsenic equivalent to 0.06 per cent as metallic arsenic. It is a brown almost odorless and tasteless powder, readily soluble in water and dilute alkalies. Arsenoferratose is a solution of this substance obtained by dissolving 5 parts in 68 parts of water with the aid of a little sodium hydroxide, 20 parts glycerin, 6 parts alcohol, and 1 part Angostura essence. For the determination of the iron and arsenic in the solution of Arseno- ferratose and applicable also for the salt the following method is recom- mended by the laboratory of the American Medical Association. Twenty-five mils are evaporated to a viscid consistency in a capacious tared crucible and the residue heated in a drying oven at 100° for three hours to a constant weight. (The author doubts if it is possible to obtain a constant weight by evaporating a mixture containing this quantity of glycerin.) The weight of the evaporated residue multiplied by 4 should be about 23. Now carefully incinerate and ignite. After cooling moisten with nitric acid, ignite and finally take up with 10 mils hydro- chloric acid. The solution is diluted with 30 mils of water and when cold 882 ORGANIC SUBSTANCES 3 grams potassium iodide are added and the mixture allowed to stand for an hour in a well-stoppered bottle at the ordinary temperature. It is then titrated with N/10 sodium thiosulphate. The iodin liberated should require about 12.5 mils of N/10 sodium thiosulphate. If arsenoferratose is treated as given below, and the arsenic titrated with N/10 iodin solution, the iodin consumed should indicate the pres- ence of not less than 0.003 gram arsenic per 100 mils arsenoferratose. Fifty mils o£ the arsenoferratose contained in a distillation flask of about 500-mils capacity, are heated on a water-bath and evaporated to about one-third of its original volume. To the residue are now added 80 mils of arsenic-free concentrated hydrochloric acid and 20 mils arsenic- free 25 per cent solution of ferrous chloride, and the arsenic chloride dis- tilled over, the receiver being kept well cooled by means of cold water. The contents of the receiver are then supersaturated with sodium bicar- bonate, and the arsenic titrated with the N/10 iodin solution. Arsen-triferrin Arsen-triferrin is an iron arsenoparanucleate containing arsenic in organic combination and standardized to contain a definite amount of arsenic by diluting with iron paranucleate. It should contain about 16 per cent of iron, 0.1 per cent of arsenic (As), and 2.5 per cent of phos- phorus, all in organic combination. Arsen-triferrin is an orange-colored, tasteless powder, soluble in dilute alkalies from which it can be precipitated by the addition of an acid. It is also soluble in about 8 per cent of hydrochloric acid on warming. Arsenic Peptonate Arsenic peptonate, for which no definite composition is assigned, is prepared by adding a solution of arsenic bromide in strong alcohoKo beef peptone suspended in dilute alcohol, and stirring. The finished product contains about 45 per cent arsenic figured as AS2O3. For assaying this product pour 5 mils concentrated sulphuric acid upon 0.2 gram sample in a 200-mil beaker. Heat so that SO3 fumes are barely given off, until the liquid becomes clear (cooling and adding more sulphuric acid in case the liquid evaporates to less than a layer J inch thick before becoming clear). Dilute and neutralize the acid with sodium hydroxide. Acidify slightly. Make alkaline with sodium bicarbonate and titrate with N/10 iodin. Each 0.4046 mil N/10 iodin represents 1 per cent AS2O3. If 0.2 gram sample is taken each mil N/10 iodin equals 0.004942 gram AS2O3. ORGANIC ARSENIC COMPOUNDS 883 Enesol. Mercury Salicylarsenate This is a white substance containing 38 to 39 per cent mercury and 14 to 15 per cent arsenic. It is soluble in water and is employed in syphilis. Recently there has been reported x a series of new arsenic compounds prepared from a chlorarsenobehenoleic acid or chlorarsenobehenic acid. The first reports claimed the latter, but in both cases the strontium salt is called "Elarson." The acid is prepared by heating arsenic trichloride with behenic or behenoleic acid. It is a brownish-red oil, insoluble in water, but dissolving in the alkali solvents and in olive oil. The salts resemble soaps. Methyl derivatives have been prepared. The new compounds are recommended for secondary anemia, phthisis, chorea, neuralgia, and Basedow's disease. Elarson contains about 13 per cent arsenic, 6 per cent chlorine and 9 per cent strontium. It is a white, amorphous, tasteless powder, insolu- ble in water, but slightly soluble in alcohol and ether. Elarson is broken up by boiling with alcoholic potash under a reflux. If the alcoholic liquid is diluted, a portion of the solution on treatment with dilute sulphuric acid and filtered, will give characteristic tests for arsenic and chloride. The balance of the solution, diluted with water, acidified with dilute hydrochloric acid and filtered, will yield a precipitate of stron- tium oxalate on treatment with ammonia and ammonium oxalate. 1 Forshn. Therap. d. Gegenw., 54, 1. Am. 403, 106. CHAPTER XXIII PROTEINS AND DIGESTIVES PROTEINS The chemistry of the proteins in so far as it affects the drug analyst is confined to those groups which occur in beef and vegetable extracts, predigested meat products, extracts of fish livers, casein, and nucleic acid preparations. A detailed account and description of all of the different classes of proteins is not essential in a work of this kind, but a brief sum- mary of the characteristics of the important groups will enable the chemist to comprehend the" fundamental status of protein chemistry. Accompanying the proteins in beef are the xanthin derivatives, creatin and creatinin. These nitrogenous substances, though they are not pro- teins, are always important factors in studying meat and vegetable extracts. The xanthin bases have been described in the section on Alkaloids. S. B. Schryver in the new edition of Allen, Vol. 8, p. 17 et seq., gives a very comprehensive resume of the chemistry of the proteins. He classi- fies the proteins as follows: Simple proteins, conjugated proteins, and derived proteins. The first class include the protamines, highly nitro- genous substances; histones, also containing considerable nitrogen; albumins, water-soluble proteins of egg white and blood serum; globulins, insoluble in water and widely distributed; prolamines, soluble in 70 to 90 per cent alcohol, gliadin being an example; glutenins; scleroproteins or albuminoids. The second class include the nucleoproteins; glycopro- teins; phosphoproteins ; hemoglobins, and lecitho proteins. The last class include the metaproteins obtained by acid and alkaline digestion of the proteins; proteoses, peptones, and polypeptides derived by the action of enzymes and the latter also by synthesis. The proteins differ from one another in the number and kind of amino acids which they yield on hydrolysis. They are formed by the conden- sation of several amino acids according to the scheme: R 1 R 11 R m I i NH 2 — CH— CO OH HNHCH— COOH HNHCH— CO OH HNH R N —COOH H PI— 884 PROTEINS AND DIGESTIVES 885 The hydrolytic products of the proteins thus far isolated and identified include about a score of amino acids, the simplest being glycine or amino- acetic acid, (NH 2 )CH 2 COOH. Others thus far identified are: Alanine, alpha-aminopropionic acid, CH3CH(NH)2COOH. CH3. Valine, alpha-aminoisovaleric acid, yCH • CH(NH 2 )COOH. CH 3 CH3. Leucine, alpha-aminoisocaproic acid, yCK • CH 2 • CH(NH 2 )COOH. CH 3 Isoleucine, alpha-amino-beta-methyl-beta-ethyl propionic acid. CH3 \ >CH-CH(NH 2 )COOH C 2 H 5 / Phenylalanine, beta-phenyl-alpha-amino propionic acid, C 6 H 5 CH 2 CH(NH 2 )COOH Serine, beta-hydroxy-alpha-aminopropionic acid, OHCH 2 CH(NH 2 )COOH Cystine, Di-beta-thio-alpha-aminopropionic acid, HOOC • CH(NH 2 ) • CH 2 S— S • CH 2 • CH(NH 2 )COOH Aspartic or aminosuccinic acid, HOOC CH 2 CH(NH 2 ) COOH. Glutamic or alpha-aminoglutaric acid, HOOC • CH 2 ■ CH 2 • CH(NH 2 ) • COOH Arginine, alpha-amino-delta-guanidine valeric acid, NH 2 / NH=C — CH 2 • CH 2 • CH 2 • CH(NH 2 ) ■ COOH \ / NH Lysine, alpha-epsilon-diaminocaproic acid, H 2 N • CH 2 • CH 2 • CH 2 • CH 2 • CH(NH 2 ) • COOH Caseinic or diaminotrihydroxydodecanic acid, Ci 2 H 2 gOsN 2 . Histidine, beta-iminazole-alpha-aminopropionic acid, CH / \ N NH / \ HC==C— CH 2 • CH(NH) 2 • COOH . 886 ORGANIC SUBSTANCES Proline, alpha-pyrrolidine carboxylic acid, CH2 == CH2 I I CH 2 CHCOOH \ / NH Hydroxyproline, hydroxy pyrrolidine carboxylic acid, C5H6O3N. Trytophan, beta-indole-alpha-aminopropionic acid, C— CH 2 • CH • (NH 2 ) • COOH / \ CeHi CH \ / NH The vegetable proteins belong to the albumins, globulins, glutelins, and prolamines, no representative of the remaining groups having been found. Qualitative Reactions of Proteins. — Nitrogen and sulphur are present in proteins and may be recognized by the usual methods of detecting them in organic combination. Some water-soluble proteins coagulate on heating and others require the presence of a little acid. Strong alco- holic solutions usually precipitate. Concentrated nitric acid causes a precipitate with proteins, and potassium ferrocyanide added to a solution distinctly acid with acetic acid produces a white flocculent precipitate. Some of the alkaloidal reagents, notably phosphotungstic and phosphomo- lybdic acids, Mayer's reagent, potassium-bismuth iodide, tannic and picric acid, yield precipitates. The derived proteins, especially the proteoses and peptones, are not affected by the majority of the precipitating reagents. Gelatin does not precipitate with ferrocyanide. Aqueous solutions of proteins give, with Millon's reagent (a freshly prepared solution of mercurous nitrate with nitrous acid in solution), a white precipitate which turns brick-red on boiling, and the supernatant liquid becomes red after standing. Solid proteins turn red on boiling with the reagent. Sodium chloride must be absent when this test is performed. Another important color reaction is the biuret test, which is obtained when a solution of an albumin or globulin is treated with a few drops of a very dilute solution of copper sulphate followed by a slight excess of fixed alkali. The blue precipitate formed by the copper will dissolve with the production of a violet color. With certain proteoses a reddish or rose color is obtained. PROTEINS AND DIGESTIVES 887 MEAT PRODUCTS Beef Extract Beef Extract is a product obtained by extracting fresh meat with boiling water and concentrating the liquid portion by evaporation, after the removal of the fat. Sodium chloride is generally added, and the finished extract is of semi-solid or pasty consistency. It should contain not less than 75 per cent of total solids, nor over 27 per cent of ash, not over 12 per cent sodium chloride, not over 0.6 per cent of fat and not less than 7 per cent of nitrogen. Fluid meat extract has the same characteristic ingredients, but is concentrated to a lower degree. Good meat extract contains no albumin. Creatin is constantly present in flesh, creatinin, its dehydrated form, occurs to some extent in flesh and in larger amount in meat extracts. These two substances are therefore characteristic components of meat extracts. /NH 2 Creatin, NH : C< X N(CH3)CH 2 /NH— CO Creatinin, NH : C< \ X N(CH 3 )CH 2 Meat extract contains the following substances: Non-nitrogenous Extractives. Nitrogenous Extractives. Glycogen Creatin Dextrin and Sugars Creatinin Lactic acid Xanthin Inositol Hypoxanthin Uric Acid Urea Carnin Inositic acid Taurin Methods of Analysis of Meat Extracts. — The methods given are those of the Association of Official Agricultural Chemists 1 and were developed and adapted to this class of products by F. C. Cook. The liquid and semi-liquid extracts should be removed from the con- tainer and mixed before sampling. Warming will expedite the mixing of pasty extracts. Liquid preparations often show a sediment and this should be carefully removed and mixed with the sample. If the sample is in the form of cubes, 10-12 units should be ground. 1 Jour. A. O. A. C, 1, 1915-1916, 280. 888 ORGANIC SUBSTANCES Moisture. — Use 2 grams of powdered preparations,. 3 grams of pastes and 5 to 10 grams of liquids. Dissolve the pasty preparation in water and dry with sufficient ignited sand, asbestos, or pumice to absorb the solution. The determination is made in a vacuum drying-oven at the temperature of boiling water, or in the open in a current of hydrogen. The moisture is usually expelled in five hours. Ash. — Char a quantity of the substance, representing about 2 grams of the dry material, and burn at a low heat, not to exceed dull redness, until free from carbon. If a carbon-free ash does not result, exhaust the charred mass with hot water, collect the insoluble residue on a filter, burn till the ash is white or nearly so, and then add the filtrate to the ash and evaporate to dryness. Heat to low redness till the ash is white or grayish white and weigh. Total Phosphorus. — Use 2 to 2.5 grams of a solid or paste and an equiva- lent quantity of a liquid preparation. Digest in a Kjeldahl flask with concentrated sulphuric acid and potassium sulphate. After the solution becomes colorless, cool, add 100 mils of water and boil for a few minutes. Neutralize with ammonia, cool, and precipitate with magnesia mixture. After standing with an excess of ammonia, this crude precipitate is then to be filtered off, washed with dilute ammonia, dissolved in dilute nitric acid and precipitated with ammonium molybdate. The balance of the determination follows the usual course of a phosphate analysis. Chlorine. — Dissolve about 1 gram of the sample, prepared as directed above in 20 mils of 5 per cent sodium carbonate, evaporate to dryness, and ignite as thoroughly as possible at a temperature not to exceed dull redness. Extract with hot water, filter, and wash. Return the residue to the platinum dish and ignite to an ash; dissolve in sufficient nitric acid (1 in 10), add this solution to the water extract. Add a known volume of N/10 silver nitrate in slight excess, stir well, filter, and wash thoroughly. To the filtrate and washings add 5 mils of saturated solution of ferric alum and a few mils of dilute nitric acid. Titrate the excess of silver with N/10 ammonium or potassium thiocyanate until a permanent light- brown color appears. Fat. — Transfer the residue from the determination of moisture to a continuous extraction apparatus and extract with anhydrous ether for sixteen hours. Dry the extract at the temperature of boiling water for thirty minutes, cool in a desiccator, weigh; continue at thirty-minute intervals, this alternate drying and weighing to constant weight. Total Nitrogen. Gunning Method. — Place .7 to 3.5 grams, according to the nitrogen content, of the substance to be analyzed in a digestion flask (Pyrex type, 500-mil capacity). Add 10 grams powdered potassium sulphate and 15 to 25 mils concentrated sulphuric acid (.1 to .3 gram crystallized copper sulphate also may be added). Place the flask in an PROTEINS AND DIGESTIVES 889 inclined position and heat below the boiling-point until frothing ceases. Digest for a time after the mixture is colorless or nearly so, or until oxida- tion is complete. Cool, dilute with about 200 mils of water, add a few pieces of granulated zinc or pumice stone, if necessary to prevent bumping, a little phenolphthalein, and sufficient strong sodium hydroxide solution to make the reaction strongly alkaline. Connect the flask with a con- denser, using a rubber stopper through which passes the lower end of a Kjeldahl connecting bulb, and distill until all the ammonia has passed over into a measured quantity of standard acid (N/2 is usually the best strength to employ) and titrate with standard alkali. The first 150 mils of distillate will generally contain all of the ammonia. Before receiving the distillate in the acid, the latter should be treated with a few drops of methyl red, which is the indicator to be used for this titration. 1 mil of N/1 acid = .01703 gram NH 3 1 mil of N/1 acid = .014 gram N 1 mil of N/2 acid = .008515 gram NH 3 Nitrogen X6.25 = Protein (Meat, Food and Feeding Stuffs) Nitrogen X 6.38 = Casein and Albumin Nitrogen X 5.7 = Wheat Protein. Insoluble Protein. — Dissolve 5 grams of powdered preparations, 8 to 10 grams of pasty extracts, or 20 to 25 grams of fluid extracts in cold water. Filter and wash with cold water. Transfer the filter and contents to a Kjeldahl flask and determine the nitrogen as directed above. However, if a large amount of insoluble matter is present, transfer the weighed sample to a graduated flask, make up to a definite volume, shake thoroughly, filter through a dry folded filter, and determine the nitrogen in an aliquot of the filtrate. Deduct the percentage of nitrogen in the total filtrate from the percentage of total nitrogen to obtain the percentage of nitrogen in the insoluble protein. Multiply this percentage by 6.25 to obtain percentage of insoluble protein. Coagulable Protein. — Prepare a solution of the sample as directed above. Employ as large an aliquot of the filtrate as practicable, neu- tralize to phenolphthalein by the addition of acetic acid or sodium hydrox- ide, whichever may be necessary, add 1 mil N/l acetic acid, boil for two to three minutes, cool to room temperature, dilute to 500 mils and pass through a dry folded filter. Determine nitrogen in 50 mils of the filtrate. Ten times the percentage of nitrogen so obtained, subtracted from the percentage of soluble nitrogen (total nitrogen minus the per- centage of nitrogen occurring as insoluble protein) gives the percentage of nitrogen present as coagulable protein. Multiply this figure by 6.25 to obtain the percentage of coagulable protein in the sample. 890 ORGANIC SUBSTANCES Proteoses, Peptones and Gelatin. — Modified Tannin-Salt Method. — Use the filtrate obtained in the estimation of coagulable proteins. Trans- fer a 50-mil aliquot to a 100-mil graduated flask, add 15 grams sodium chloride and 10 mils of cold water, shake until the sodium chloride has dissolved and cool to 12° C. Add 30 mils of 24 per cent tannin solution, cooled to 12° C, fill to mark with water previously cooled to 12° C, shake and allow the mixture to stand at a temperature of 12° C. for twelve hours or overnight. Filter at 12° C. through a dry filter, transfer 50 mils of the filtrate to a Kjeldahl flask and add a few drops of sulphuric acid. Place the flask in a steam-bath, connect with a vacuum pump and evapo- rate to dryness. Determine the nitrogen in the residue. Conduct a blank determination, using the same amount of reagents and correct the result accordingly. Multiply the corrected result by 2 and deduct the amount of nitrogen as found from the amount of nitrogen determined in another 50-mil aliquot of the filtrate from the coagulable proteins without the tannin-salt treatment; the difference multiplied by 6.25 gives the percentage of proteoses, peptones and gelatin. Meat Bases. — Deduct from the percentage of total nitrogen the sum of the percentages of nitrogen obtained in the determination of insoluble proteins, coagulable proteins, and proteoses, peptones and gelatin, to obtain the percentages of nitrogen in the meat bases. Multiply the result by 3.12 to obtain the percentages of meat bases. Ammonia. Folin Method. — Employ the apparatus shown below. A is a wash bottle one-quarter full of 10 per cent sulphuric acid; B is a tube containing the sample; C is a rubber disk and D is a 5-mil spray bulb to prevent spray from being carried over in the tube E, which contains the standard acid; F is a safety bottle. PROTEINS AND DIGESTIVES 891 Mix 1 gram of the meat extract with 2 mils N/l hydrochloric acid, wash into tube B with about 5 mils of ammonia free water. Place a measured amount of N/25 or N/50 sulphuric acid or hydrochloric acid in tube E. Then add 1 mil of saturated potassium oxalate solution to the sample in tube B, introduce a few drops of kerosene and finally add just sufficient saturated potassium carbonate solution to render the mixture alkaline. Place the tubes in position at once, pass air through the appa- ratus and titrate the standard acid in tube E at hourly intervals, until ammonia ceases to be given off, using methyl red as indicator. Proteoses and Gelatin. — Use the filtrate obtained in the estimation of coagulable protein. Evaporate to small volume and saturate with zinc sulphate (about 85 grams to 50 mils, avoiding such an excess as would later cause bumping). Let stand several hours, filter and wash the pre- cipitate with saturated zinc sulphate solution, place the filter and pre- cipitate in a Kjeldahl flask and determine the nitrogen. Or, if the pre- cipitate is voluminous, make up to a definite volmne with saturated zinc sulphate solution, filter and determine the nitrogen in an aliquot of the filtrate. Subtract the nitrogen thus obtained from the nitrogen in the filtrate from the coagulable protein to obtain the nitrogen of the pre- cipitated protein (proteoses and gelatin). Acid Alcohol-soluble Nitrogen. — Transfer 10 mils of an aqueous solu- tion of the sample (10 grams dissolved in sufficient water to make 100 mils) or, if the sample is insoluble in water, 1 gram and 10 mils of water, to a 200-mil glass-stoppered measuring cylinder, add 1.2 mils of 12 per cent hydrochloric acid, mix and add absolute alcohol to the 200-mil mark. Mix thoroughly and set aside for several hours. Filter off a 100- mil aliquot, evaporate alcohol and determine nitrogen in the residue. Creatin. — Dissolve about 7 grams of the sample in cold (20° C.) ammonia-free water in a 150-mil beaker, transfer the solution to a 250- mil measuring flask, dilute to the mark and mix thoroughly. Transfer a 20-mil aliquot of this solution to a 50-mil measuring flask, add 10 mils 2/N hydrochloric acid and mix. Hydrolyze in an autoclave at 117 to 120° C. for twenty minutes, allow the flask to cool somewhat, remove and chill under running water. Partially neutralize the excess of acid by adding 7.5 mils of 10 per cent sodium hydroxide solution free from carbonates, dilute to mark and mix. Make a preliminary reading on 20 mils to ascertain the volume to use to obtain a reading of approxi- mately 8 mm. and transfer to a 500-mil graduated flask. Add 10 mils of 10 per cent hydroxide solution and 30 mils saturated picric acid solu- tion. Mix and rotate for thirty seconds and let stand exactly 4| minutes. Dilute to the mark at once with water, shake thoroughly and read in a Duboscq colorimeter, comparing the color with N/2 potassium dichromate set at 8 mm. 892 ORGANIC SUBSTANCES If the reading is too high or too low (above 9.5 or below 7 mm.), cal- culate the quantity necessary to obtain a reading of about 8 mm. The strength of the dichromate solution used must be checked against a standard creatin solution. To obtain the values, divide 81 by the reading and multiply by the volume factor to obtain milligrams of creatinin; sub- tract from the combined creatinin value the equivalent of the pre-f ormed creatinin (determined below); this value Xl.16 gives creatin, which, divided by the weight of the sample and multiplied by 100 gives the per cent of creatin. Creatinin. — Measure about 5 mils of the solution employed above into a 500-mil measuring flask, add 10 mils of 10 per cent sodium hydroxide solution and 30 mils of saturated picric acid solution, mix and rotate for thirty seconds. Allow to stand exactly 4| minutes, then dilute to the mark at once with water. Shake thoroughly and read the depth of color after standing. If the reading is less than 7 or over 9.5 mm., repeat, calculating the quantity of solution necessary to obtain a reading of about 8 mm. Express the results as per cent of creatinin, making the calculations as indicated above. Nitrates. Phenoldisulphonic Acid Method. — Reagents. Phenoldisul- phonic Acid Solution. — Heat 6 grams of phenol with 37 mils of concen- trated sulphuric acid on a water-bath, cool, and add 3 mils of water. Standard Comparison Solution. — Dissolve 1 gram of pure dry potas- sium nitrate in water and dilute to 1 liter. Evaporate 10 mils of this solution to dryness on a steam-bath, add 2 mils of the phenoldisulphonic acid solution, mix quickly and thoroughly by means of a glass rod, heat for about one minute in a steam-bath and dilute to 100 mils. One mil of this solution is equivalent to .1 mg. of potassium nitrate. Prepare a series of standard comparison tubes by introducing amounts ranging from 1 to 20 mils of this solution (.1 to 2 mg. of KNO3) into 50-mil Nessler tubes, adding 5 mils of strong ammonium hydroxide and diluting to 50 mils. These standard tubes are permanent several weeks if kept tightly stoppered. Determination. — Weigh 1 gram of the sample if a solid or 10 mils if liquid, into a 100-mil flask, add 20 to 30 mils of water and heat on a steam- bath for fifteen minutes, shaking occasionally. Add 3 mils of saturated silver sulphate solution for each per cent of sodium chloride present, then 10 mils of basic lead acetate solution and 5 mils of alumina cream, shaking after each addition. Make up to the mark with water, shake and filter through a folded filter, returning the filtrate to the filter until it runs through clear. Evaporate 25 mils of the filtrate to dryness, add 1 mil of the phenol disulphonic acid solution, mix quickly and thoroughly by means of a glass rod, add 1 mil of water and 3 to 4 drops of concentrated sulphuric acid and heat on a steam-bath for two to three minutes, being PROTEINS AND DIGESTIVES 893 careful not to char the material. Then add about 25 mils of water and an excess of ammonium hydroxide, transfer to a 100-mil graduated flask, add 1 to 2 mils of alumina cream if not perfectly clear, dilute to the mark with water and filter. Fill a 50-mil Nessler tube to the mark with the filtrate and determine the amount of potassium nitrate present in the sample by comparison with the standard comparison tubes. If the solution is too dark for comparison with the standards, dilute with water and correct the result accordingly. Glycerin. See pages 548-549. Yeast Extract Yeast on hydrolysis yields extractives similar to those obtained from meat. The water extract on evaporation darkens and acquires an odor similar to beef extract, and on superficial examination the two products appear identical. Yeast extract contains no creatin or creatinin while in a typical meat extract from 10 to 20 per cent of the total nitrogen is present in the form of these bodies. The distribution of the xanthin bases differs in meat extracts, xanthin, and hypoxanthin predominate while in yeast extracts adenin and guanin predominate. The most impor- tant test for determining the nature of the extract is the estimation of the creatin and creatinin. The analytical methods of the A. O. A. C. for meat extracts are applicable to yeast extracts. Beef Peptone Beef peptone is usually prepared by digesting lean beef with pine- apple juce in a steam-jacketed boiler with a mechanical stirrer. When the beef is digested the liquid is strained and concentrated in vacuo to a thick syrup, dried, and pulverized. The product is often sold as Beef Meal and is sometimes mixed with cacao and sugar. Beef Jelly Beef jelly is prepared by mixing 50 parts of beef peptone, with 43 parts beef extract and 7 parts of sodium chloride. Beef, Iron, and Wine Beef, Iron, and Wine is a liquid preparation consisting of extract of beef or beef peptone dissolved in an hydro alcoholic solution (wine) with the aid of sodium or ammonium citrate and accompanied by iron chloride. Cinchona alkaloids, digestives, coca, and other drugs are often added to the formula. 894 ORGANIC SUBSTANCES The actual medicinal content of this class of preparations vanished to such an alarming extent at one time that the Bureau of Internal Revenue ruled that a special tax must be paid for the sale of any product having a protein content lower than 1.4 per cent. This value is a minimum for the average product made according to the National Formulary. Cod-liver extracts when made from fresh livers probably contain some of the proteins occurring in beef extract. If made from putrid livers a number of simpler amines such as butylamine, amylamine, asellin, mor- rhuine, will be found. These extracts are also combined with wine beef extract, beef peptone, hypophosphites, creosote, iron chloride, and citrates. Ruddirnan and Kebler, 1 from a critical study of Beef, Iron, and Wine made according to the National Formulary, conclude that the product should possess the following characteristics: 50 mils when assayed by the Gunning method for total nitrogen should yield not less than . 10 gram of nitrogen coming from the beef extract. If the amount of nitrogen obtained by the barium carbonate method exceeds .006 gram the excess is to be considered as coming from an ammonium compound and is to be deducted from the total nitrogen obtained, the remainder representing the nitrogen coming from the beef extract. Fifty mils should contain not less than .07 gram nor more than .08 gram of iron calculated as metallic iron. The percentage of alcohol should not be under 14 nor over 20. The nitrogen determination is complicated when ammonium salts are present. The National Formulary preparation calls for sodium citrate, but many proprietary preparations are made up with ammonium citrate. Some workers determine the total nitrogen by the Gunning procedure, and then estimate the ammoniacal nitrogen in another sample by distillation with magnesium oxide, the difference between the figures obtained representing the percentage of nitrogen as beef extract. Ruddirnan and Kebler believe that magnesium oxide liberates some of the ammonia from nitrogenous constituents of the beef extract and recommend distillation with barium carbonate. Fifty mils of the sample in a 500-mil Kjeldahl flask are treated with 200 mils of water,. 3 grams of barium carbonate, and a few pieces of granulated zinc or pumice. The flask is connected with the condenser in the usual way and the distillate received in N/10 acid. The ammonia liberated is considered as coming from added ammonium salts. The developement of Folin's aeration method for ammonia pre- viously described under meat extracts took place subsequent to the researches of Kebler and Ruddirnan and is probably applicable to the Beef, Iron, and Wine products. 1 U. S. Dept. Agri., Bu. Chem. Bull., 137, p. 194. I PROTEINS AND DIGESTIVES 895' Nucleoproteins. Phosphoproteins The nucleic acid of yeast is used therapeutically in combination with some of the heavy metals. The solutions of the compounds are usually antiseptic and non-irritant. The silver compound is known as Nargol and Argentose, the mercury compound is called Mercurol and the copper compound Cuprol. Nucleic acid and nucleoproteins contain phosphorus in organic com- bination. They are distinguished from phosphoproteins by the fact that the latter on treatment with 1 per cent sodium hydroxide at 37° undergo hydrolysis and yield their phosphorus in the form of phosphoric acid which can be directly precipitated with ammonium magnesium chloride, whereas the phosphorus of nucleoproteins remains in organic combination when subjected to the same treatment. Nucleic acids yield a number of substances on hydrolysis with acids; the purine bases guanin, adenin, xanthin, and hypoxanthin, cytosin, uracil, and thymin. derivatives of pyrimidin; carbohydrates and their degradation products, formic and levulinic acids; and phosphoric acid. Casein and Vitellin Special preparations of casein are used as concentrated foods for diabetic patients, neurasthenics, and convalescents. They are often com- bined with glycerophosphates, and the casein is rendered soluble by sodium bicarbonate, sodium citrate, sodium or potassium phosphate, etc. Products of the Sanatogen, Eulactol, Plasmon, Nutrose and Sanose types fall in this class. Argonin is a soluble silver casein compound which furnishes a non-irritant antiseptic useful in venereal diseases. Casein compounds are very useful as a means of administering other medicinal agents such as lithium, mercury, silver, iron, arsenic, alkaloids, salicylates, etc. The nomenculature in relation to casein is confusing. Casein or free casein is the base-free or uncombined protein; calcium casein or caseinate is the neutral compound that is believed to be present in fresh normal milk, the CaO being present to the amount of 1.50 per cent; basic calcium casein or caseinate is the compound consisting of casein with 2.50 per cent CaO; calcium paracasein or paracaseinate is the insoluble compound formed by the action of rennet on calcium casein; paracasein or free paracasein is the base free or uncombined protein. Free casein may be separated from milk or its soluble compounds by precipitating with acetic or mineral acids. The amount of casein is obtained by determining the nitrogen by the Kjeldahl-Gunning method and multiplying by 6.38. Casein is a phosphoprotein. This class of substances is distinguished 896 ORGANIC SUBSTANCES from others by the fact that on treatment with 1 per cent sodium hydroxide at 37° for twenty-four to forty-eight hours the whole of the phosphoric acid is set free from organic combination. Vitellin Vitellin in combination with silver is known as Argyrol. Vitellin is a phosphoprotein of acid character which is obtained as a white granular residue on extracting egg yolk with large quantities of ether. It is soluble in saturated sodium chloride, and reprecipitated on adding an excess of water. DIGESTIVES The digestive ferments occupy a prominent place among modern remedial agents. The conditions under which the different ferments act are usually dissimilar; pepsin, for instance, develops its greatest digestive power at a temperature of 40° C. and in a weak acid medium, while the properties of diastase show to the best advantage in a neutral medium. While it was formerly held that a mixture of ferments could be counted upon to be active only with respect to one of the ingredients, it now appears that the value of these mixtures can be attributed to all of their components. The commercial ferments are extractive preparations containing the enzymes which bring about the transformation of foods in the plants or animals containing them. Proficiency in assaying digestive preparations and interpreting the results obtained can be acquired only with considerable practice. The results are always comparative, and the dynamics of the reactions are perhaps more closely connected with physiological chemistry than with those answering the laws of stable elements and compounds. Many factors influence the manipulations. Degrees of concentration should be taken into consideration. In all cases it is good practice to run parallel tests with standard products of known potency. In endeavoring to check claims of digesting value advanced on the label or in the literature of an individual product, due regard must be taken of the fact that for a long time the laboratory of every firm had its own methods of testing, and the claims were based on the results of assays by these methods. The Proteoclastic Enzymes The chief commercial preparations of this class are pepsin, pancreatin, and papain. Pepsin Pepsin is obtained from the mucous membrane of the stomach of the hog, and when purified the commercial product is a yellowish-white scale PROTEINS AND DIGESTIVES 897 or amorphous powder, consisting of albuminous material with varying amounts of the ferment. Pepsin is dispensed in liquid and solid form. The nqmds are usually elixirs, syrups, or wines, and are prepared with saccharated pepsin. The combinations include bismuth and ammonium citrate, ferric pyrophos- phate, extract of cinchona, strychin, gentian, beef peptone, and occasion- ally other drugs. Pancreatin and other digestives are sometimes com- bined with pepsin. Lactated pepsin is a mixture of pepsin, pancreatin, diastase, and maltose, with hydrochloric and lactic acids. This same combination with aromatic powder is sold in tablet form. Digestive powders contain pepsin, pancreatin, bismuth subcarbonate, and aromatics. In tablets and pills pepsin will be found in combination with one or more of the other digestives, bismuth salts, gentian, charcoal, sodium bicarbonate, Nux Vomica, caffein, antipyretic drugs, Capsicum, ipecac, ginger, cerium oxalate, inspissated ox gall, salol, and cinchona alkaloids. Pepsin is an ingredient of chewing gums. The products sold at the present time actually contain detectable quantities of pepsin, which was not the case before the activities of control legislation. Quantitative determinations of pepsin are actually measures of the digestive power of the particular specimen under examination. Two specimens of the same appearance and weight may possess totally different potencies. The pepsin of the U. S. standard is 1-3000, which means that one part of pepsin will digest 3000 times its weight of specially prepared egg albumin at a specified temperature and within a specified period. There are no standards for products containing pepsin, and there is no way of actually measuring the quantity of pepsin present, unless a decla- ration on the label indicates that a certain amount of pepsin of a definite potency has been used. In the latter case a measure of the digesting power will furnish an approximate idea of the quantity used. Prepara- tions containing pepsin, especially those of liquid nature, are subject to fairly rapid deterioration, and while they may be potent as remedial agents when freshly made, they will often be inert after a few months or even weeks unless preserved under special rigid conditions which are generally impracticable from a commercial and household standpoint. Determination of Proteolytic Activity U. S. P. Method for Pepsin. — Mix 25 mils of normal hydrochloric acid V. S. with 275 mils of distilled water and dissolve .1 gram of pepsin in 150 mils of this liquid. Immerse a hen's egg, which is not less than five nor more than twelve days old and has been kept in a cool place, in boiling water during fifteen minutes. As soon as the egg has sufficiently 898 ORGANIC SUBSTANCES cooled to handle it, remove the pellicle and all of the yolk; at once rub, the albumen through a clean, dry hair or brass, No. 40, sieve, reject the first portion that passes through the sieve, and place 10 grams of the suc- ceeding portion in a wide-mouthed bottle of 100 mils' capacity. Immedi- ately add 2 mils of the acid liquid and, with the aid of a rubber-tipped glass rod, moisten the albumen uniformly. Again add 2 mils of the acid liquid, repeat the manipulation with the glass rod, and with gradually increasing portions of the acid liquid, until the total amount added measures 20 mils. Thoroughly separate the particles of albumen from each other, rinse the rod with 15 mils more of the acid liquid, and, after warming the mixture to 52° C, add exactly 5 mils of the solution of pep- sin. At once cork the bottle securely, invert it three times, and place it in a water-bath that has previously been regulated to maintain a temper- ature of 52° C. Keep it at this temperature for two and one-half hours, agitating the contents every ten minutes by inverting the bottle once. Then remove it from the water-bath, pour the contents into a conical measure having a diameter not exceeding 1 cm. at the bottom, and trans- fer the undigested egg albumen which adheres to the sides of the bottle to the measure with the aid of small portions (about 15 mils at a time) of distilled water, until the total amount used measures 50 mils. Stir the mixture well and let it stand for half an hour; the deposit of undis- solved albumen does not then measure more than 1 mil. The relative proteolytic power of pepsin, stronger or weaker than that just described, may be determined by ascertaining through repeated trials the quantity of the pepsin solution, made as directed in the assay, required to digest, under the prescribed conditions, 10 grams of boiled and disintegrated egg albumen. Divide 15,000 by this quantity expressed in mils to ascertain how many parts of egg albumen one part of Pepsin will digest. Method for Liquid Pepsin. — Chestnut has developed a method for determining proteolytic activity which in skilled hands has given excellent results. Preparation of Sample. — Add to 50 mils of the liquid under exami- nation the requisite quantity of either N/10 HC1 or H2O or both, to make the preparation of N/10 acid strength when diluted with N/10 HC1 to 90 mils. Preserve the sample in a refrigerator. Preparation of Reagents. 1. Standard Pepsin. — Powder a good grade of acid soluble U. S. P. pepsin and pass it through a No. 60 sieve; dry in vacuo over H2SO4, pass again through a sieve and preserve in a stop- pered bottle over H2SO4.' The exact pepsin equivalent of the dry powder must be ascertained by the U. S. P. process, and this may be expressed in percentage based on the supposition that the U. S. P. product is 100 per cent pure. PROTEINS AND DIGESTIVES 899 2. Pepsin Solutions. — Weigh off definite amounts of the standard pepsin from a weighing tube into the requisite quantity of N/10 HO to make, 2a: A 1 per cent solution. 26: A .1 per cent solution. These should be freshly prepared, since weak solutions of pepsin in N/10 HC1 suffer decomposition on standing . 3. Add 1 mil of N/10 HC1 to 9 mils of the sample. 3a. Immerse a stoppered flask containing 45 mils of the sample and 5 mils of N/10 HO in boiling water for fifteen minutes and filter. 36. Immerse a stoppered test-tube containing 18 mils of solution 3 in boiling water for ten minutes, and after cooling, add 2 mils of solution 2a, and filter if necessary. 4. Ricin Solution. — The cheap commercial " Ricin Praparatnach Jacoby " manufactured in Germany is ground to a No. 60 powder, thoroughly mixed and dried, and then stored in a desiccator. Digest 1 gram of this powder for one hour at 37.5° C. in 100 mils of 5 per cent of Nad solution, cool and filter. Method. — To each of fifteen tubes first add. from a burette, 2 mils of the ricin solution and a half mil of N/10 HO. Heat to 37.5° C. and then add the quantities of solutions Nos. 26, 3, 3a and 36, indicated in the following tables. Measure off solutions 3a first and then pour in the solutions to be tested as rapidly as possible from graduated pipettes, taking note of the total time consumed in the process and beginning first with tube No. 1 and then following in natural sequence. Sample Tables No. of tubes 1 2 No. of mils 3 added 0. .25 No. of mils 3a added 1 . .75 Time of digestion in minutes . No digestion 68 42 28 19 Series II No of tubes 1 2 No of mils 3a added 1 . .75 No. of mils 36 added 0. .25 Time of digestion in minutes . . Xo digestion 68 42 28 19 Series III No. of tubes 1 2 NoofmilsN/lOHCl 1. .75 No. of mils 26 0. .25 Time of digestion in minutes . . No digestion 98 42 28 19 3 4 5 .50 .75 1.00 .50 .25 0.00 3 4 5 .50 .25 0.00 .50 .75 1.00 3 4 5 .50 .25 0.00 .50 .75 1.00 900 ORGANIC SUBSTANCES If the solutions to be tested are not clear they should be filtered repeatedly through a hardened filter. If, however, it be found that they cannot thus be clarified, check tubes for comparing the end digestion products should be made containing the varying amounts of the prepa- ration made up with N/10 HC1 in place of ricin. After the addition of the solutions to be tested, the test-tubes are immersed in the 37.5° C. bath at once, preferably placed in corresponding order in a partitioned square or oblong wire rack, such as is used in bacterio- logical work. The tubes are shaken and examined from time to time for one or two hours, or overnight in the case of very weak solutions. The time of beginning the digestion and also the time in minutes of com- plete digestion for each tube should be noted (preferably with a stop watch) as indicated in the tables above given. If the rate of digestion is the same in each series 3 contains exactly .1 per cent of pepsin, the amont present in the original solution being .2 per cent. If the rate is more rapid in I than in II or III it is stronger, the comparative strength being closely indicated by the time of action in the tubes containing less of the solution. If the rate of clearing is most rapid in III, the solution contains some substance which interferes with the action of the pepsin, and this must be removed in some way as by dialysis * or evaporation in vacuo or at a low temperature until, upon reexamination, and further dilution or concentration, the rate of diges- tion is identical or nearly so in each series. One mil of 26 represents .001 gram of pepsin. Smaller quantities of pepsin may be determined in the same way by comparing with more diluted solutions of standard pepsin. As small a quantity as .00005 gram of U. S. P. pepsin can thus be readily detected by its nearly complete solvent action on the ricin ppt. inside of two hours and .000005 gram shows marked action on the ricin inside of the same time. After four hours 7 digestion, the absence of any appreciable solvent action, as judged by ocular inspection, indicates the absence of pepsin. The results should be expressed in per cent calculated on the basis of pepsin of U. S. P. quality, being 100 per cent. The proteolytic value of pills, tablets, powders, and liquid prepara- tions containing pepsin may be determined by following the general directions recommended in these methods. In all cases due regard must be taken of the reaction of the solution before it is added to the egg albu- 1 Dialysis tubes are made by pouring collodion into test-tubes or small Erlenmeyer flasks allowing it to dry a little, adding more collodion and drying again two to five minutes or until the collodion does not adhere to the finger when touched, and then removing the film and the glass and plunging it at once into water. The films should be kept moist until used. The special advantage of these tubes is that they are emi- nently adapted for quantitative work. PROTEINS AND DIGESTIVES 901 men. If alkaline it should be neutralized and rendered slightly acid with dilute hydrochloric acid. The presence of preservatives and inhibitory substances must be determined. Papain Commercial papain consists of the inspissated juice of the Carica papaya or paw paw, usually mixed with starch and sometimes the juices of other vegetable growth, some of which have been found to be extremely toxic. Commercial papain is sometimes adulterated with pepsin and while pepsin is probably more valuable as a digesting agent, its admixture with paw paw juice and sale at an exorbitant figure for papain is not to be commended. The ferment of papain acts best in a slightly alkaline media. It may be concentrated from the dried juice by dissolving it in water, dialyzing, and precipitating with alcohol. Papain either in the crude or concen- trated form is used in the preparation of a limited number of digestive products. In the tropics the juice is used by the natives in the treatment of eczema, warts, intestinal worms, ulcers, and many lands of foul sores, and in diphtheria to dissolve the false membrane in the throat. Its greatest use, however, is for the purpose of rendering tough meat tender. In this respect paw paw juice possesses the property of pineapple juice, the latter being largely employed in the preparation of beef peptone. In testing papain and the preparations containing it the following method of Rippetoe : is recommended : Prepare egg albumen as directed under pepsin assay U. S. P. 9th revision. Introduce into a 4-oz. wide-mouth flint bottle 40 mils of a .1 per cent sodium hydroxide solution and add 10 grains of the disintegrated albumen; stopper the bottle and shake vigorously until the albumen is broken up. Then add the papain in fine powder and mix by shaking gently for fifteen seconds. Place the bottle in a water-bath for six hours, removing the bottle every ten minutes and shaking gently for fifteen seconds. At the end of this period transfer the mixture to a 100-mil graduated stoppered cy finder, rinse the bottle with water, add the rinsing to the mixture and make the volume up to 70 mils with water. Set the cylinder aside and after standing for one hour read off the volume of the deposit. The deposit may be read a second time after standing sixteen to eighteen hours (overnight), which seems to give more positive results, especially if the volume is large. The method is also applicable for determining the digestive value of pineapple juice. A sample of dry pineapple juice, using 1 gram of dry juice, neutralized with sodium hydroxide, added to 10 grams of the 1 Journal of Industrial and Engineering Chemistry, 4, 1912, 517. 902 ORGANIC SUBSTANCES albumen in 35 mils .1 per cent sodium hydroxide solution, with three hours' digestion, left a residue of 2 mils, reading after eighteen hours, while a blank read 41 mils. Shelly * suggests the following modification of Sorensen's test for assay- ing papain. Four grams casein (Hammerstein) are dissolved in 100 mils of alkali solution containing 4 mils N/l sodium hydroxide. To 25 mils of this solution are added 25 mils water containing .1 gram dried juice and the mixture digested in an incubator at 37° C. for four hours. To 20 mils of the liquid are added 10 mils of a 40 per cent formaldehyde solution just neutralized with N/5 sodium hydroxide. This mixture, equivalent to .04 gram of sample is titrated with N/5 sodium hydroxide, using phenolphthalein, and at least 1 mil should be required to neutralize the amino acids formed, after subtracting the amount required by a similar mixture without the juice. Thorburn's Method. 2 — .4 gram of papain and .75 gram sodium bicar- bonate are dissolved in 100 mils of distilled water and heated to 50-55° C. Lean round steak is scraped to a pulp, rejecting gristle, fat, etc.; 10 grams are placed in a 200-mil digestion flask, the papain-sodium bicar- bonate solution added and digested for four hours, maintaining a temper- ature of 50-55°. The flask is shaken every ten minutes and at the end of the digestion the contents of the flask are poured into a measuring cylinder and allowed to stand at rest for one-half hour. Not more than 10 mils of residue should remain. A blank digestion of the meat pulp and bicarbonate should be run simultaneously with the papain digestion. After reading the volume of the residue, the mixture is warmed to 50-55° 1.5 mils concentrated hydrochloric acid is added and again digested for four hours, shaking at ten-minute intervals. At the end of this period the volume of the residue should be less than 3 mils. Pancreatin Much has been written concerning the ferments of the pancreas and the activity of commercial pancreatin preparations. The characteristic ferments of the pancreas include amylopsin, a starch digestant, trypsin, a protein digestant, and steapsin, a fat-splitting lipase. Pancreatin is extracted from the pancreas of the hog by water or very dilute acid, the solution precipitated by means of alcohol, and the pre- cipitate dried at 40° C. Pancreatin is used as a medicinal agent in a form representing a com- mercially high concentration of the active ferments, such as pancreatin pure and saccharated pancreatin. It is made up with pills and tablets 1 Analyst. 39. 170. 2 J. Amer. Pharm. Assn., 1915, 4, 224. PROTEINS AND DIGESTIVES 903 alone and with other ferments, with inspissated oxgall, Nux Vomica, Taraxacum, colocynth, bismuth salts, aromatics, salol, etc. Enteric pills of pancreatin are coated with keratin or salol, these agents being sup- posedly undissolved in the stomach, but allow the pills to pass into the intestine, where it is disintegrated by the alkaline medium, and the digest- ive made available. Pancreatin is an important remedy in intestinal indigestion. Liquid pancreatin preparations are usually in the form of elixirs, and may contain pepsin, bismuth and ammonium citrate, strychnin, rhubarb, Hydrastis, and other tonics and stomachics. Pancreatin is also com- bined with malt extract. The amylolytic value of pancreatin and its preparations is determined as follows : Method for the Routine Valuation of Diastase Preparations, by W. A. Johnson. 1 — A standard starch paste is prepared from potato starch which has been purified by washing with water, and dried firstly for three hours in a current of air, and subsequently for four hours at 80° C, so as to contain 90 per cent of anhydrous starch; 22.22 grams of this starch ( = 20 grams of anhydrous starch) are mixed with 100 mils of cold water, and the mixture poured into 800 mils of boiling water, boiled for ten minutes, and made up to 1000 grams. In each test 50 grams of the paste are used in 250-mil flasks clamped in a water-bath kept at 40° C, and ten minutes is fixed as the time of action. In the case of liquid malt extracts, about 10 mils diluted to 100 mils are used, while 200 to 500 mg. of dry preparations in 100 mils of water are usually suitable quantities. Definite quantities of these dilute liquids (say 1 mil to 6 mils) are added to the flasks containing the starch paste, and after about eight minutes, a few drops are tested with iodin solution (2 grams of iodin and 4 grams of potassium iodide in 250 mils). The test is repeated with 100 mils of starch paste in the different flasks, just as in Lintner's method of determin- ing diastatic activity, new limits being found between which the real value must lie, and in every case the disappearance of all color is taken as the end-point. In expressing the results in starch-converting power, allowance should be made for the fact that the statements of the manu- facturers appear to be based upon results obtained with commercial starch which contains about 15 per cent of water. The tryptic energy of pancreatin is determined as follows by the method of Field and Gross : A casein solution of .2 per cent strength is prepared by dissolving 100 mg. of pure casein in 2 mils of N/20 sodium hydroxide, by aid of very gentle heat, and diluting to 50 mils. A dilute acid is prepared with 50 mils of alcohol, 49 mils of water and 1 mil of 100 per cent acetic acid. 1 Jour. Am. Chem. Soc, 1908, 30, 798. 904 ORGANIC SUBSTANCES The trypsin solution is made by dissolving in the proportion of 20 mg. to 50 mils of water. Six portions of the casein solution of 5 mils, each containing 10 mg, of casein, are measured out, and diminishing portions of the ferment solu- tion are transferred to test-tubes, but always made up to 5 mils. For the milligram of casein the weights of ferment may be taken as follows: 2 mg., 1.3 mg., .8 mg., .5 mg., .3 mg., and .1 mg. The series of test-tubes containing casein and ferment so charged are incubated one hour at 40° C. and then withdrawn from the bath. To each tube 3 drops of the dilute acetic acid are added. If full digestion has taken place the acid fails to produce a precipitate. The last tube in which no precipitate is formed gives an approximate measure of the digesting power of the ferment, which may be sufficient. A closer result may be obtained by making up a new series of ferment solutions of just one-tenth the strength of the last. These are to be incubated with the casein solution in the same way, the final tests being made as before. When tested in this manner, 1 part of trypsin should digest at least 75 parts of casein. Method for Determining the Tryptic Value of Pancreatin, C. F. Ramsay. 1 — The materials required for the test are as follows: .5 gram pancreatin added to sufficient distilled water to make 50 mils of solution; 900 mils of milk containing 1.8 grams of sodium bicarbonate; 2 grams of rennin (1 : 30,000 in ten minutes or equivalent) and 1 mil of 6 per cent acetic acid (U. S. P.) added to 50 mils of distilled water. After warming the milk, place exactly 50 mils in a cylindrical tube of about 100-mils capacity. Prepare several such tubes and place in a water-bath, maintaining the temperature at 40° C. Add to the tubes of milk the following amounts of pancreatin solution : Mils 8.33 (1 : 600) 7.69 (1 : 650) 7.14 (1 : 700) 6.66 (1 : 750) 6.25 (1 : 800) In each case note the exact time when the pancreatin is added, mix well, and after digesting fifteen minutes place 5 mils of the digested milk in a test-tube, add 3 mils of the rennin solution, and shake well. No precipitate indicates that the casein has all been peptonized and that the pancreatin is stronger than the strength tested. For example, if there was no precipitation at 1 : 700, but there was a precipitation at 1 : 750, 1 Jour. Ind. and Eng. Chem., 3, 1911, 823. PROTEINS AND DIGESTIVES 905 then it would be necessary to run more digestions between 1 : 700 and 1 : 750. Make a fresh solution of pancreatin and use the following amounts : Mils 7.04 (1 : 710) 6.94 (1 : 720) 6.84 (1 : 730) 6.75 (1 : 740) In this manner it can be determined quite accurately how many times its own weight of milk a given sample of pancreatin will peptonize. In order to get accurate results the test must be carried out strictly in accord- ance with directions. As stated above, acid will precipitate peptonized milk, therefore just enough acid is added to the rennin solution so that 3 mils of this solution will neutralize the sodium bicarbonate in 5 mils of the peptonized milk. Then the rennin will do its work, for it will not form the precipitate in an alkaline solution. Attention must be called to the fact that pancreatin in a neutral solution deteriorates quite rapidly. Therefore this solution should be made up the last thing, so it can be added immediately to the milk. The amount of pancreatin solution suggested is sufficient for testing the strengths as indicated. Determination of Milk-Curdling Properties. — .16 gram pancreatin and .65 gram sodium bicarbonate are placed in a 500-mil flask or bottle, 50 mils water at a temperature of 45° C. are added, the whole well shaken and allowed to macerate fifteen minutes. While this is going on 250 mils of fresh milk are warmed to 45° C. and, at the end of the maceration period, added to the pancreatin solution, mixed and maintained at 45° for one and one-half hours. The container is gently agitated from time to time during the first half hour to disintegrate the curd and at the end of this time there should be no appreciable curd. At the expiration of one and one-half hours there should be no appreciable curdy mass. No quantitative methods have been reported for determining the lipase action. Mellanby and Wooley have determined that steapsin is very unstable. In alkaline solution at 40° it decreases 10 per cent an hour, 50°, 50 per cent an hour and at 60° is completely destroyed in five minutes. In the acid solution its destruction depends on the H ion concentrate. It is stable in the presence of large quantities of the higher fatty acids, but is destroyed quickly by small amounts (.02 NHC1) of free mineral acids. It is rapidly destroyed by trypsin. Serum or egg albumin pro- tects steapsin from trypsin in activating pancreatic juice because of the presence of anti-trypsin in them. The action of steapsin is accelerated by bile and bile salts, but unaffected by electrolytes such as neutral salts. 906 ORGANIC SUBSTANCES Bauer, 1 in reporting some experiments performed with pancreatin on free fat, describes a process which might be useful in a study of the lipase action. In using these preparations they are first formed into a homogeneous paste with water, which is then mixed with the fat to be hydrolyzed in the proportion of about 5 per cent. When the oil or melted fat is mechani- cally stirred with the paste, emulsification soon occurs. After thirty minutes to one hour, 5 per cent sodium carbonate solution is gradually added, the addition being so regulated that the emulsion when tested with red and blue litmus paper always produces a violet stain on each. After about one to two hours the requisite amount of alkali (corresponding to about 25 per cent of the fatty acids) will have been added, and the mass will usually have become too thick from the separation of fatty acids for the stirring to be continued. The mass is then left to itself. After five hours from 60 to 80 per cent of the fat will usually have been hydrolyzed, and the hydrolysis will be complete in one to four days. In one of the typical experiments quoted, 100 grams of ox-tallow were melted and mixed at 40° C. with 6 grams of pancreas powder made into a paste with 60 mils of water. The mass was stirred for an hour at 35° C, after which 80 mils of N/l sodium carbonate solution were added little by little. After five hours 66 per cent of the fat had been hydrolyzed, and the reaction was complete in four days. If hydrolysis ceases after a time when pancreas-lipase is allowed to act on a fat (almond oil), this is due to an alteration of the activity of the enzyme; further hydrolysis takes place if a fresh quantity of pancreatic juice be added, and sometimes, also, on addition of a fresh quantity of the fat. The hydrolysis of fat by fresh active pancreatic juice is acceler- ated, but not increased, by addition of bile. The hydrolysis is com- pleted more rapidly if the pancreatic juice be added in successive portions; in this case, addition of bile does not accelerate the hydrolysis, but indeed sometimes retards it. There are a number of commercial preparations of the pancreas gland which contain larger quantities of the ferments, or at least show greater digesting power, than the standard pancreatin of the Pharmacopoeia. Some of these have received distinctive names such as Holadin, Panase. Some firms claim to have succeeded in concentrating a trypsin compara- tively free from other digesting agents, which has a proteolytic value con- siderably greater than pancreatin. These products are usually desig- nated as Trypsin with the name of the manufacturer hyphenated. Much criticism has been directed toward those manufacturers who offer digestive preparations containing simultaneously pepsin and pan- creatin, but the results of recent experiments seem to indicate that these 1 Soc. Chem. Ind., 29, 1909, 149. PROTEINS AND DIGESTIVES 907 ferments exercise no destructive action upon one another, and that with the proper degree of acidity they can be kept in the same solution perma- nently for two and one-half years at least, the loss of activity noted by other observers having been due entirely to the reaction of the solution and to the degree of such reaction. Solutions containing 10 per cent each pepsin and pancreatin, containing HO in graduated strength, from .075 to .65 per cent volume absolute, after two and one-half years, have retained their full pepsin activity. Those containing less than .35 per cent have retained their full trypsin activity, and those of .075 per cent have retained in full the amylopsin activity with that of the trypsin and pepsin. Pepsin and pancreatin can be administered in such a solution, or mixed together in dry form, in all proportions, and the pepsin will retain its full proteolytic power and the pancreatin both its full amylolytic and tryptic activity, which latter is developed after passing the stomach and becoming mixed with the alkaline secretions of the intestine. 1 AMYLOCLASTS The chief starch-converting products of medicinal importance are diastase, malt extract, and pancreatin. The latter has already been considered. The commercial diastases are more or less concentrated forms of the enzyme, which are prepared either by growing the fungus on wheat bran and extracting with water, or by extracting malt, con- centrating the aqueous solution under reduced pressure, and precipitating with alcohol. The crude diastase is then dried, or if a liquid preparation is desired, it is made up with the filtered precipitate. Diastase is used alone for the treatment of ailments arising from faulty digestion of starch, and is dispensed in tablets, capsules and in liquid form. It is also combined with other digestants in general remedies for dyspepsia. The activity of diastase products is determined by measuring the amount of maltose produced in an excess of soluble starch, or by the power of the enzyme to form products which no longer give a color with iodin solution. Both of the methods can be used with diastase, but the former is unsatisfactory for malt extracts because of the relatively small amount of active enzymes present admixed in the first place with a con- siderable quantity of maltose. The second method is the simplest and most rapid, and is the one generally employed in commercial work. The success of the operation depends on the close adherence to details, and these are well emphasized in the method of Francis which was originally worked out for testing Taka-Diastase. 1 A. Zimmerman, Jour. Ind. and Eng. Chem., 3, 1911, 751. 908 ORGANIC SUBSTANCES Taka-Diastase Test, 1-150 in Ten Minutes. Solution for Diastase. — Weigh out very accurately .1 gram diastase. Transfer to a small mortar containing a small quantity of water and grind the mixture. Transfer to a 75-mil measuring flask, washing out the mortar very carefully, the washing being poured into the flask and adjusted to 75 mils. Ten mils of the above solution (containing .133+ gram of diastase) will convert 150 times its weight (2 grams) of starch into hydrolyzed derivatives in ten minutes. Standard lodin Solution. — Dissolve 2 grams of pure iodin in q. s. H2O containing 4 grams KI and adjust to exactly 250 mils. For the test dilute 1.5 mils of the solution to 1000 mils with distilled water. Fill this dilution into 2-ounce clear vials, putting 50 mils (meas- ured by means of a measuring flask) into each. Place vials on a white porcelain slab. (The strong solution of iodin should be kept in a green or amber bottle in a dark place.) Starch Paste. — Pour about 900 mils of distilled water into a tared vessel (preferably copper) and bring to vigorous boiling. Into this pour slowly 20 grams starch suspended in about 30 mils of cold distilled water, stirring vigorously. Stir well and continue to boil for ten minutes so as to produce a homogeneous thin jelly (use only absolutely neutral potato starch). Place container and starch paste on balance (with tare) and add distilled water q. s. to adjust weight of starch solution to exactly 1000 grams. Cool with vigorous stirring to 40° C. If paste is not absolutely uniform discard it, as lumps invalidate the test. Provide a sufficient number of cylindrical glass tubes, into which, after counterbalancing, pour exactly 100 grams starch paste. Nearly immerse the tubes of paste fitted with rubber stoppers in a water-bath at 40° C. and allow to stand until contents have attained this temperature; after which the digestive solution is added and test begun. Water-bath. — In order to have an even temperature it is best to arrange a metal water-bath containing a perforated rack. Put in the proper measure of water and keep at a temperature of 40° C. by means of a gas burner. Large flat-bottomed tubes are best suited for containing the starch solution, but vials of any kind having wide mouths can be used. Digestion. — Add 10 mils of the diastase solution accurately measured with pipette to starch solution in the tube, close the tube by means of a tightly fitting rubber stopper and shake vigorously, meantime note the minute and second at which shaking began. Place in water-bath and allow digestion to proceed, shaking the tube occasionally to prevent the formation of a ring of starch around the upper surface of the liquid, which does not digest so rapidly and interferes with the end reaction. At the end of ten minutes' digestion fill a medicine dropper with the digested solution and drop two drops into one of the iodin vials. Agitate PROTEINS AND DIGESTIVES 909 the contents of the vial; no blue color indicative of starch should be pro- duced. Method of Sherman, Kendall, and Clark. — The starch paste is pre- pared as follows : Enough clean air dry potato starch to contain 10 grams of water-free substance is suspended in about 100 mils of cold distilled water; enough more distilled water to make one liter is poured into a 2- to 3-liter flask immersed in a brine bath and connected with a reflux condenser. The bath is then heated and if the water boils the heating is stopped so that the water may cool somewhat, then the suspension of starch is poured very carefully into the hot water, the heating resumed and the paste boiled two hours under the reflux condenser. This long boiling renders the starch paste less viscous, more homogeneous and transparent, and more easy of digestion by the amylase. In order to determine how long the boiling of the starch paste should be continued, experiments were made in which 250-mil portions of the paste were treated with 40 mg. of taka-diastase No. 2 dissolved in 20 mils of water and the time required for digestion to products giving no color with iodin was determined as follows: Boiled one-half hour, required fifty minutes; one hour, required forty-six minutes; one and one-half hours, thirty-six minutes; three hours, thirty-three minutes; six hours, thirty minutes. Hence boiling beyond one and one-half hours had little effect upon the digestibility of the stach as thus determined. Moreover, it was noted that up to two to three hours the solutions remained color- less while on three to six hours' boiling they became slightly yellowish. Two horn's was therefore decided upon as the best length of time for boiling the starch paste. The paste at a temperature not above 40° is weighed out in 250-gram portions (equivalent to 2.5 grams anhydrous starch) into Erlenmeyer flasks of 350-400 mils' capacity and immersed in a water-bath kept at 40°. The desired amount of enzyme is then introduced along with 20 mils of water (in which the enzyme may be dissolved, or which may be used to wash it into the flask), the contents of the flask well mixed and the tempera- ature of 40° carefully maintained. The digestion is considered completed when .25 mil of the contents of the flask removed and mixed with 5 mils of the dilute iodin test solution x in a test-tube shows, when viewed against a white background, no color which can be distinguished from that of the untreated iodin test solution. The experiment is repeated with dif- ferent amounts of enzyme, if necessary, until that amount is found which completes the digestion in thirty minutes (d=one minute). The result may then be conveniently expressed by dividing the weight of starch 1 Two grams of iodin and 4 grams of potassium iodide are dissolved in 250 mils water. For use, 2 mils of this solution are diluted to 1 liter and 5 mils of this dilute solution are employed for each test. 910 ORGANIC SUBSTANCES (2.5 grams) by the weight of enzyme required to digest it under these fixed conditions. U. S. P. Method for Assaying Diastase. — Mix a quantity of potato starch, purified as directed under Pancreatin, equivalent to 5 grams of dry starch, in a beaker with 10 mils of cold distilled water. Add 140 mils of boiling distilled water, and heat the mixture on a water-bath with con- stant stirring for two minutes, or until a translucent, uniform paste is obtained. Cool the paste to 40° C. in a water-bath previously adjusted to this temperature. Prepare a fresh solution of .1 gram of Diastase in 10 mils of distilled water at 40° C. and add it to the paste. Mix them well and maintain the same temperature for exactly thirty minutes, stirring frequently; a thin, nearly clear liquid is produced. Add at once .1 mil of this liquid to a previously made mixture of .2 mil of N/10 iodin V. S. and 60 mils of distilled water; no blue or reddish color is produced. W. L. Baker's Method for Assaying Diastase. — A clean grade of potato starch is thoroughly washed and carefully dried at a low temperature and finally at a higher temperature to about a 10 per cent moisture con- tent. The exact moisture content to be determined in a separate experiment. For the test enough of the starch is taken (about 11 grams) to make to 500 mils of an exactly 2 per cent (anhydrous) starch content. The boiling of the paste should be continued for ten minutes with con- stant stirring to keep from burning. For each test quantities of exactly 25 grams of the paste are weighed in a series of 250-mil flasks placed in a water-bath and kept at a temperature of 40° C. The iodin test solu- tion is made by dissolving 2 grams of iodin and 4 grams of potassium iodide in 250 mils of distilled water, 2 mils of this solution is then diluted with pure water to make 1000 mils. The diastase solution is made by dissolving or suspending .2 gram of diastase in 100 mils of distilled water. The solutions are used in the following way : Definite volume's of the solu- tion are added to the different flasks containing the starch solution and the mixtures are well shaken. The volumes added may be as follows: 4 mils, 4.5 mils, 5 mils, 5.5 mils, 6 mils. In eight minutes tests are begun by removing volumes of 5 drops from each of the digesting mixtures by a pipette, and adding this to 5 mils of the dilute iodin solution in a clear white tube standing over white paper. If at the end of ten minutes drops from one of the flasks fail to give the iodin reaction, we are ready for the more accurate test; for example, the flasks containing 5 mils diastase solution did not respond to the iodin reaction, but the one containing 4.5 mils did, then a second test should be carried out under exact ly the same conditions as the former, using 4.6, 4.7, 4.8, 4.9, and 5 mils diastase solu- tion to 25 grams of the starch paste. The diastase solution must be of the same temperature as the starch paste. The test is carried to the loss of all color. The diastase solution should have been just previously made PROTEINS AND DIGESTIVES 911 and, if working for any length of time, fresh solutions should be made from time to time, as aqueous solutions of diastase are very unstable and soon lose their power of conversion. The dilute iodin solution should not be put in the tubes until just before it is needed. The method of Johnson used for determining the amylolytic value of pancreatin is applicable to diastase and malt preparations. Malt Extract Malt extract is prepared by extracting ground malt with water and concentrating to the consistency of molasses. It is a viscid liquid contain- ing from 45 to 55 per cent of maltose, protein, water, ash, and diastase. When ready for market it is often treated with 8 to 15 per cent of alcohol. Malt extract is often combined with other remedial agents, cod liver oil, Cascara sagrada, digestives, hypophosphites, creosote, ferric pyrophos- phate, quinin, strychnin, Yerba santa, etc. Malt preparations are assayed for digestive power in the same way as diastase. As remedial agents malt preparations are used almost exclusively for their amylolytic value. Malt, however, appears to contain ferments possessing proteolytic activity, and attention must be directed to the work on this subject which has been conducted by Wahl x and the procedure adopted by him in measuring this activity. A mixture of preferably about one part of crushed malt and four parts of water, inoculated with lactic acid ferment, was subjected to a tempera- ture varying between 50 and 60° C. maintained for about thirty minutes to destroy all organisms except the one to be propagated for producing the desired acid, and holding the temperature of the mash at 50° to 55° C. for about twenty-four to fourty-eight hours, during which time from 1 to 2 per cent of lactic acid is formed. The grains are then separated from the liquid, and same is used for the malt extractions made as follows: One part, either of finely ground malt (Seek mill set at 1.0) or of coarsely ground or crushed malt (Seek mill set at .5), is extracted with four parts of the bacterial liquor above mentioned, previously diluted with water so as to give the desired strength of 105 per cent acidity. Varying tem- peratures were used for the extractions as specified below. The peptic strength of the malt extracts was determined by auto- digestion and by means of a modified " gelatin liquefying strength" method of Schidrowitch. In every instance the peptic strength of the malt extract was compared with that of a standard solution of pepsin of known strength. The method of conducting the test, as well as the prep- aration of the pepsin standard, are given below. 1 8th International Congress of Applied Chemistry, XIV, 221. 912 ORGANIC SUBSTANCES Preparation of the Gelatin. — Thirty-two grams of the gelatin are dissolved in 318 mils of distilled water by gently heating the same. One- third of a gram of finely ground egg albumen dissolved in 50 mils of dis- tilled water is then added and the gelatin solution cooled to 52° C. The temperature is then raised to 85 ° C. in five minutes, and then to 100° C. where it is held for ten minutes. While still hot the gelatin is filtered into a glass beaker containing .5 gram of thymol, which readily dissolves in the liquefied gelatin. The solution is then tubed, each tube receiving 6 mils and the tubes closed with cork stoppers to prevent evaporation. Method of Work. — (Testing of proteolytic strength.) The gelatin tube is gently warmed, preferably in a thermostat or water-bath, until the contents are liquefied. Five mils of the liquid under examination are then added to the tube. A blank is prepared at the same time, con- taining 5 mils distilled water. The tubes are then placed in an incubator held at 37.5° C. and incubated for four hours. After this they are placed in ice water at 2° C. and the time required for solidification of gelatin is noted. From the number of minutes required by the tube containing the liquid under examination, the time required for the solidification of the blank is subtracted, and the results tabulated for purposes of com- parison. It must be remembered that a malt extract in which the enzyme has been destroyed, and which contains from 1 per cent to 2 per cent of lactic acid, has a slight power to liquefy gelatin, to the extent of requir- ing from one to two minutes longer to solidify than the blank. Pepsin Standard. — .15 gram of pepsin of 10,000 strength is mixed with 10 grams of powdered sugar, and dissolved in 100 grams of distilled water. Five mils of this solution are added to a gelatin tube. The con- tents of a tube so prepared requires seven minutes for solidification. The amount of coagulable albumen remaining in the malt extracts after the same had been subjected to the action of the peptonizing enzyme for a given period and at a given temperature was determined by means of the coagulation test conducted in the following manner: The extract was filtered perfectly clear and then heated to 75° C, where it was held for thirty minutes and then allowed to cool to 25° C. Ten mils of this solution were introduced into a centrifuge tube graduated in 1/10 mils. The tube was placed in the centrifuge and run for a period of four minutes, at a speed of about 2500 revolutions per minute. The amount of coagulable albumen in the tube is then read in terms of 1/10 mil. CHAPTER XXIV OILS The chemist is often confronted with the problem of determining the identity of an oil, or knowing its identity to determine its purity; he may be required to determine the kind and amount of an oil in a mixture of which a certain oil is one of the constituents; he may have to know the different kinds of oils and the approximate proportion of each in a mix- ture of oils; and finally it may develop that it is essential to determine the identity of an oil used in the preparation of soaps or the salts of the higher acids used as the basis of plasters and complex ointments. The characteristics of the individual fixed and volatile oils and fats are described in great detail in works devoted to this subject, and it is not the province of this work to go into a detailed account of all of them. But there are a few oils which are used extensively as remedial agents or as the components of pharmaceutical preparations to which attention must be directed. Of the fixed oils, castor, olive, cod-liver, chaulmoogra, croton, theobroma, linseed, and mineral oils are used therapeutically, and in addition to these cotton-seed, sesame, sweet almond, arachis (peanut) enter into the composition of pharmaceutical mixtures, while the solid fatty substances, petrolatum, lard, tallow, and palm oil have also an extended use. The most important volatile oils encountered by the drug chemist include those of bitter-almond, anise, betula, gaultheria, cajuput, chenopodium, copaiba, cinnamon, cloves, eucalyptus, penny- royal, juniper berry, peppermint, pinus pumilio, santalwood, sassafras, savine, tansy, and turpentine. The chemical characteristics, as well as the therapeutic value of some of these oils, are dependent on certain well-defined chemical individuals, of which often the pure oil is entirely composed, and their consideration is best effected among the systematic groups of chemical individuals to which the individuals belong. General Methods for Examination. — Specific Gravity. — To be deter- mined with pycnometer or Westphal balance. Refractive Index. — To be obtained with a refractometer. Acid Value. — Use 20 grams of fat or oil and 50 mils 95 per cent alcohol. Titration figure obtained can be used for calculating free fatty acid as 913 914 ORGANIC SUBSTANCES oleic. One mil N/10 alkali = .0282 gram oleic acid. One mil N/2 alkali = .1410 gram oleic acid. Saponification Value. — The saponification value of a fat or oil is the quantity of potassium hydroxide (expressed in milligrams) consumed in saponifying 1 gram of the fat or oil. It is determined as follows: Weigh accurately, in a flask of 200 to 250 mils' capacity, 1.5 to 2 grams of the filtered fat or oil and add to it 25 mils of alcoholic potassium hydroxide accurately measured from a burette or pipette. Insert into the neck of the flask, by means of a perforated stopper, a glass tube from 70 to 80 cm. in length and from 5 to 8 mm. in diameter and heat the flask on a water- bath for half an hour, frequently imparting a rotatory motion to the contents. Then add 1 mil of phenolphthalein and titrate the excess of potassium hydroxide with half -normal hydrochloric acid. Make a blank test at the same time, using exactly the same amount of alcoholic potas- sium hydroxide. The difference in the number of mils of half -normal hydrochloric acid consumed in the actual test and the blank, multiplied by 28.055 and divided by the weight of the fat or oil taken, gives the saponification value. Iodin Number. — The iodin value or number of a fat or oil indicates the proportion of iodin absorbed under specified conditions. It is deter- mined as follows: Introduce about .8 gram of a solid fat or about .3 gram 1 of an oil, accurately weighed, into a glass-stoppered bottle of 250 mils capacity, dissolve it in 10 mils of chloroform, add 25 mils of iodo-bromide accurately measured from a burette or pipette, stopper the bottle securely, and allow the mixture to stand for hah an hour 2 in a cool place protected from light. After this time it must still retain a brown color; if the color is not brown a new test should be started, using smaller a quantity of the fat or oil. Then add in the order named 30 mils of potassium iodide, 100 mils of distilled water, and N/10 sodium thiosulphate in small, suc- cessive portions, shaking thoroughly after each addition, until the color of the mixture becomes quite pale. Then add a few drops of starch and continue the addition of N/10 sodium thiosulphate until the blue color is discharged. While this test is being carried out, make a blank test by mixing exactly the same quantities of iodo-bromide and chloroform and titrating the free iodin with N/10 sodium thiosulphate as directed above. The difference in the number of mils of N/10 sodium thiosulphate con- sumed by the blank test and the actual test, multiplied by 1.269 and divided by the weight of the fat or oil taken, gives the iodin value. Unsaponifiable Matter. — Weigh from 5 to 10 grams of the oil or fat into a 300-mil Erlenmeyer flask, add 100 mils of alcoholic potash (40 1 .15 to .18 gram for linseed oil, .18 to .2 gram for cod liver oil, and .8 to 1.0 gram for oil of theobroma. 2 One hour is required for castor oil and linseed oil. OILS 915 grams per liter) and heat on the water-bath until saponification is complete. A small funnel in the neck of the flask will serve as a reflux condenser. After saponification, which usually takes from thirty to forty-five minutes, the hot soap solution 1 is poured into a 16-oz. Squibb separator and the flask rinsed with two 25-mil portions of 95 per cent alcohol, making a total of 150 mils of 95° alcohol. The separator is cooled to room temper- ature by shaking under the tap and 75 mils of fight petroleum ether boil- ing below 80° added. The petroleum ether dissolves in the alcohol, form- ing a clear solution. About 125 mils of water are next added and the mixture shaken. At this point the petroleum ether will separate and rise to the surface of the alcohol-water mixture in a clear layer. The soap solution is drawn off into a second separator and extracted twice with 50-mil portions of petroleum ether. The combined petroleum ether extracts are filtered into a tared beaker and evaporated on the water-bath. The residue is dried in a vacuum desiccator and weighed. SPECIAL TESTS Cottonseed Oil Halphen Test. — Mix carbon disulphide, containing about 1 per cent of sulphur in solution, with an equal volume of amyl alcohol. Mix equal volumes of this reagent and the oil under examination, and heat in a bath of boiling, saturated brine for one to two hours. In the presence of as little as 1 per cent of cottonseed oil, a characteristic red or orange-red color is produced. Lard and lard oil from animals fed on cottonseed meal will give a faint reaction; their fatty acids also give this reaction. The depth of color is proportional, to a certain extent, to the amount of oil present, and by making comparative tests with cottonseed oil some idea as to the amount present can be obtained. Different oils react with different intensities, and oils which have been heated from 200-210° C. react with greatly diminished intensity. Heating ten minutes at 250° C. renders cottonseed oil incapable of giving the reaction. Peanut Oil Weigh 20 grams of the oil into an Erlenmej^er flask. Saponify with alcoholic potash solution, neutralize exactly with dilute acetic acid, using 1 The alcohol content of the soap solution after dilution with water should be very close to 55 per cent by volume. It is necessary to know the volume of the alcoholic potash solution as well as the amount of alcohol used in rinsing the flask. A lower content of alcohol than 50 per cent will result in emulsions, while a higher percentage than 60 will cause the retention of a large part of the petroleum ether in solution. 916 ORGANIC SUBSTANCES phenolphthalein as an indicator, and wash into an 800- to 1000-mil flask containing a boiling mixture of 100 mils of water and 120 mils of 20 per cent lead acetate solution. Boil for a minute and then cool the precipi- tated soap by immersing the flask in water, occasionally giving it a whirl- ing motion to cause the soap to stick to the sides of the flask. After the flask has cooled, decant the water and excess of lead acetate solution and wash the lead soap with cold water and 90 per cent alcohol by volume. Add 200 mils of ether, cork and allow to stand for some time until the soap is disintegrated; heat on a water-bath, using a reflux condenser, and boil for about five minutes. In the case of oils, most of the soap will be dis- solved, while in lards, which contain much stearin, part of the soap will be left undissolved. Cool the ether solution of soap to 15-17° C. and allow to stand until all the insoluble soaps have separated out (about twelve hours). Filter upon a Buchner funnel and thoroughly wash the insoluble lead soaps with ether. Wash the ether-insoluble lead soaps into a separatory funnel by means of a jet of ether, alternating at the end of the operation, if a little of the soap sticks to the paper, with hydrochloric acid (1 to 3). Add sufficient hydrochloric acid (1 to 3) so that the total volume of the latter amounts to about 200 mils and enough ether to make the total volume of it 150-200 mils and shake vigorously for several minutes. Allow the layers to separate, run off the acid layer, and wash the ether once with 100 mils of dilute hydrochloric acid, and then with several portions of water until the water washings are no longer acid to methyl orange. If a few undecomposed lumps of lead soap remain (indicated by solid particles remaining after the third washing with water), break these up by running off almost all the water layer and then add a little concentrated hydro- chloric acid, shake, and then continue the washing with water as before. Distill the ether from the solution of insoluble fatty acids and dry the latter in the flask by adding a little absolute alcohol and evaporating on a steam- bath. Dissolve the dry fatty acids by warming with 100 mils of 90 per cent alcohol by volume and cool slowly to 15° C, shaking to aid crys- tallization. Allow to stand at 15° C. for thirty minutes. In the presence of peanut oil, crystals of arachidic acid will separate from the solution. Filter, wash the precipitate twice with 10 mils of 90 per cent alcohol by volume, and then with 70 per cent alcohol by volume, care being taken to maintain the arachidic acid and the wash solutions at a definite tem- perature in order to apply the solubility corrections given below. Dis- solve the arachidic acid upon the filter with boiling absolute alcohol, evaporate to dryness in a weighed dish, dry, and weigh. Add to the weight .0025 gram for each 10 mils of 90 per cent alcohol used in the crys- tallization and washing, if conducted at 15° C: if conducted at 20° C, add .0045 gram for each 10 mils. The melting-point of arachidic acid OILS 917 thus obtained is 71 to 72° C. Twenty times the weight of arachidic acid will give the approximate amount of peanut oil present. Arachidic acid has a characteristic appearance and may be identified by the microscope. As little as 5 to 10 per cent of peanut oil can be detected by this method. Sesame Oil Baudoin Test. — Dissolve .1 gram of finely powdered suga,r in 10 mils of hydrochloric acid (sp. gr. 1.20), add 20 mils of the oil to be tested, shake thoroughly for a minute and allow to stand. The aqueous solution separates almost at once and, in the presence of even a very small admix- ture of sesame oil, is colored crimson. Some olive oils give a slight pink coloration with this reagent. Comparative tests with known samples containing sesame oil will differentiate them. Villavecchia Test. — Add 2 grams of furfural to 100 mils of 95 per cent alcohol by volume and mix thoroughly .1 mil of this solution, 10 mils of hydrochloric acid (sp. gr. 1.20), and 10 mils of the oil by shaking them together in a test-tube. A crimson color is developed as in the Baudoin test, where sugar is used. Villavecchia explained this reaction on the basis that furfural is formed by the action of levulose and hydrochloric acid and therefore substituted furfural for sucrose. As furfural gives a violet tint with hydrochloric acid it is necessary to use the very dilute solution specified in the method. Cholesterol and Phytosterol Introduce 200 to 300 grams of the melted fat into a flat-bottomed liter flask. Close the neck of the flask with a three-holed stopper and insert through these holes : (1) a reflux condenser; (2) a right-angled glass tube, one arm of which reaches to a point 6 mm. above the surface of the melted fat, the other being closed a short distance from the flask by means of a short piece of rubber tubing and a pinch-cock; (3) a glass tube bent so that one arm reaches down to the bottom of the flask and the other serves as a delivery tube for a 700-mil round-bottomed flask containing 500 mils of 95 per cent alcohol by volume. Place the flasks containing the melted fat and the alcohol on a steam- bath and heat so that the alcohol vapor passes through the melted fat in the liter flask and is condensed in the reflux condenser, finally collecting in a layer over the melted fat. After all the alcohol has passed in this manner into the flask containing the fat, disconnect the flask from which the alcohol has been distilled and attach a tube to the short piece of rubber tubing attached to the right-angled glass tube (see (2) above) and siphon the alcohol layer back into the alcohol distillation flask. Reconnect as at first and again distill the alcohol as in the first operation. When all 918 ORGANIC SUBSTANCES the alcohol has been distilled, siphon it again into the distillation flask and extract in the same manner for a third time. Discard the fat and retain the alcohol, which now contains practically all of the cholesterol and phytosterol originally present in the fat. Con- centrate the alcoholic solution to about 250 mils and add 20 mils of potas- sium hydroxide solution (1 to 1) to the boiling liquid. Boil for ten minutes to insure complete saponification of the fat, cool to room temperature and pour into a large separatory funnel containing 500 mils of warm ether. Shake to insure thorough mixing and add 500 mils of water. Rotate the funnel gently to avoid the formation of extremely stubborn emulsions, but mix the water thoroughly with the alcohol-ether-soap solution. A clear, sharp separation takes place at once. Draw off the soap solution the wash the ether layer with 300 mils of water, avoiding shaking. Repeat the washing of the ether solution with small quantities of water until all the soap is removed. Transfer the ether layer to a flask and distill the ether until the volume of liquid remaining in the flask measures about 25 mils. Transfer this residue to a tall 50-mil beaker and continue the evaporation until all the ether is driven off and the residue is perfectly dry. If desired a tared beaker may be used and the weight of the unsaponifiable matter determined at this point. Add 3 to 5 mils of acetic anhydride to the residue in the beaker, cover the beaker with a watch-glass and heat to boiling over a free flame. After boiling for a few seconds, remove the beaker from the flame, cool and add 35 mils of 60 per cent alcohol by volume. Mix the contents of the beaker thoroughly, filter off the alcoholic solution, and wash the precipitates with 60 per cent alcohol. Dissolve the precipitate on the filter with a stream of hot 80 per cent alcohol by volume and wash the insoluble portion well with 80 per cent alcohol. Acetates of cholesterol and phytosterol are dis- solved while the greater portion of the impurities present (including paraffin and paraffin oil if present) remain behind on the filter. Cool the combined filtrate and washings to a temperature of 10-12° C. and allow- to stand at that temperature for two to three hours. During this time the acetates of cholesterol and phytosterol crystallize from the solution. Collect the crystals upon a filter, wash with cold 80 per cent alcohol and then dissolve them in a minimum amount of hot absolute alcohol. Collect the alcoholic solution of the acetates in a small glass evaporating dish, add 2 or 3 drops of water to the solution and heat if not perfectly clear. Allow the alcohol to evaporate spontaneously, the contents of the dish being stirred occasionally to mix the deposit of crystals which form upon the edges with the main body of the liquid. As soon as a good deposit of crystals has formed, collect them upon a hardened filter, wash twice with cold 80 per cent alcohol, and dry by suction, drying finally a,t 100° C. for thirty minutes, and determine the melting-point. OILS 919 The melting-point of the first crop of crystals usually gives definite information as to the presence or absence of phytosterol, but the con- clusion, indicated should be confirmed by recrystallizing the crystals from absolute alcohol and again determining the melting-point. If the crystals are pure cholesteryl acetate, the melting-point of the second crop should agree closely with that of the first. If phytosteryl acetate is present, however, a higher melting-point will be noted, as phytosteryl acetate is less soluble in alcohol than cholesteryl acetate. The melting-point of cholesteryl acetate is 114° C, that of phytosteryl acetate 125-127° C. SUMMARY OF CONSTANTS OF MOST IMPORTANT FIXED OILS USED IN MEDICINES Oil Sp. Gr. at 25° Sapon. Value Iodin Value Rotation Castor .945 -.965 .910 -.915 .9196-. 922 .935 -.950 .951 .925 .973 .925 -.930 .915 -.921 .916 -.921 .910 -.915 .911 -.926 at 15° 179-185 190-195 180-190 200-215 213 197 188-195 187-195 190-198 188-193 191-200 186-194 83-88 79- 90 150-170 104-110 103 152 33- 38 170 105-114 103-112 93-100 83-101 +23.4°-+26.1° Olive Cod Liver Croton Chaulmoogra (true oil) Gynocardia Oil (false Chaul- moogra) Strongly dexto (a) jD + 52° Theobroma Linseed Cotton S'^ed Sesame Sweet Almond Peanut Cod-liver Oil The oil expressed from the fivers of the cod is the most extensively used medicinal oil. It is dispensed in the free state and as an emulsion, and in the latter form is often combined with sodium and calcium hypo- phosphites, creosote, wine, and phosphoric acid. In soluble elastic capsules it is combined with phosphorus, creosote, and iodoform. The emulsions of the oil are not to be confused with the preparations containing cod- liver extract. The latter is really a mixture of proteins, animal acids and salts obtained by extracting the livers with an alcoholic menstruum, and little or no actual oil is present. This cod-liver extract is combined with iron and manganese peptonates, hypophosphites, strychnin, bile acids, wine, and flavoring agents. The combinations are sold under various trade names, and the labels and literature usually contain some reference to the presence of the cod-liver principles. The composition of cod-liver oil has been surrounded with more or less 920 ORGANIC SUBSTANCES mystery, and its virtues have been attributed to many causes, such as nitrogenous or alkaloidal constituents, the presence of organic iodin or of organic phosphorous, the absence of hydroxyl glycerides, etc., and it is of interest to present a few facts concerning the actual composition of a pure medicinal oil. The limits of specific gravity for a high-grade cod-liver oil are about .9196 to .922 at 25°; the iodin value averages between 150 and 170, with a few oils going above or below these figures; the index of refraction runs from 1.4783 to about 1.4822; the saponification value is from 180 to 190; and a pure oil does not congeal above — .11° C. In connection with the saponification value it should be stated that the determination is of little moment except in cases of very fight oils. With dark oils the end-point becomes so obscured that accurate titration is impossible. In one of the color tests recommended for cod-liver oil, 20 drops of the oil are placed in a watch-glass over white paper and treated with one to two drops of concentrated sulphuric acid, carefully added to avoid mixing, then the acid and oil intimately stirred, and the color change noted. When stirred, pure light-colored oils give a play of colors: at first purplish red, changing quickly to a ruby red, then a deep mahogany color and more slowly to a warm brown; around the edge, the thin layer of liquid assumes a pale-blue tinge, and on standing from one-half to one hour a purple shade develops, the mixture becoming dark brown on long standing. Some oils, especially the darker colored, pass directly to the mahogany and dark-brown stage without showing the reds, and become almost black on standing, with little or none of the purplish ring around the edge. Cusk and pollock liver oils, even after four years' standing, give the same play of colors as genuine cod-liver oil. This test may be varied by dis- solving the oil in carbon bisulphide or chloroform and adding sulphuric acid; but the same general results are obtained, though the shades of color are perhaps slightly different. The test with fuming nitric acid, described in the Pharmacopoeia, gives varying results. Some samples of known purity do not become rose red, but turn purple or brownish and then change to brick red. The description of this test is incomplete, as the color is first pale rose, which soon gives way to a brick red and very gradually changes to yellow. In some cases, also, the brick-red color does not change to yellow, but to a brown; and in others again it does not fade to a purple yellow at all, but remains reddish. In connection with the actual composition of cod-liver oil, attention must first be called to some work performed in 1890 by Gautier and Morgues, and in 1906 by Bull. The investigations of the former were concerned with the nitrogenous constituents of cod-fiver oils, and of the latter with the actual composition of a pure oil.' OILS 921 Gautier and Morgues found that the dark-colored oils, which, by the way, are never used medicinally and are really extracted from livers that are partially putrefied, contain the following well-defined nitrogenous bases: butylamine, amylamine, hexylamine, delrydrolutidine, aselline, and mor- rhurine. With the exception of the two latter, these bases have been known for some time, and no special virtue is attributed to them. Bull, 1 working with pure oils free from nitrogen, endeavored to identify the acids which made up the glycerides. He converted the mixed acids into their methyl esters, fractionated them, and separated the following acids: oleic, myristic, palmitic, erucic, gadolinic, and a new acid. The work done by Tolman and myself at the Bureau of Chemistry fully verified the conclusions of these workers and showed that a high- grade oil contained no nitrogenous constituents nor any iodin or phos- phorus compounds, but was a mixture of neutral glycerides, and that its good effects are probably attributable to its being a ready assimilable fat. The figures given in the 9th revision of the U. S. P. as applying to a cod-liver oil of standard purity are nearly all incorrect, and the test for the limit of free fatty acids is vague and of no value. Oils of high purity will often contain nearly 1 per cent of free acid. The figures and the color tests together are not limited to cod-fiver oil, but will apply equally well to carefully refined oils from other fish fivers; though it should be stated that in this investigation the oils from the livers of American cod and other American fish lose their original character and become unfit for medicinal use after three to four years. The fact that highly refined liver oils show practically the same con- stants and answer the same tests is of interest to those who are engaged in the oil business, as it shows the possibilities of a new industry for utiliz- ing oils of hitherto valueless livers, not for the purpose of adulterating cod-fiver oils but for their own value as medicinal agents. It will be noted that the determination of the identity of a fish oil is not a matter of absolute certainty. The most rational method would be the conversion of the glycerides to the metlryl esters of the acids and identif3 T ing the components of the mixture, which is a long and tedious operation and almost impossible of attainment unless the sample is of sufficient bulk. Another complication arises from the fact that the com- position of the glycerides of oils other than cod-liver oil has never been determined. Hence it appears that about all an analyst is justified in saying is that the oil is a fish oil and perhaps a fish liver oil. If it is desired to determine the quantity of oil in a capsule, a funnel with a wide bowl should be placed so that it can drain into a graduated cylinder and 5 to 10 capsules slit with a knife, dropped into the bowl of the funnel and the contents allowed to drain into the graduate. 1 Berichte, 1906, 39, 3570. 922 ORGANIC SUBSTANCES Emulsions are examined for their content of oil by transferring a measured quantity to a separatory funnel, adding water if very thick and then a quantity of alcohol until the emulsion breaks. This procedure does not always suffice, and it may be necessary to warm the diluted emulsion by rotating the containing vessel over the steam-bath, or to cool in a freez- ing mixture, or to add lead acetate. After the emulsion breaks up the oil can be shaken out with petroleum ether or ether using two or three portions and the combined solvent mixtures filtered through a dry filter and evapo- rated over the steam-bath. The residue is then measured or weighed and the figure may be used for obtaining a fairly close approximation of the quantity present in the emulsion. With substances of this nature it is difficult to obtain results of great accuracy, because the oil gains weight when heated and it is difficult to remove the last traces of the solvent. Castor Oil Castor oil, which is expressed from the seeds of Ricinus communis (Euphorbiacese) is a popular laxative remedy. It is usually dispensed in capsules and is sometimes combined with Podophyllum resin. The capsules of Aspidium (Malefern) used for the expulsion of tape worm con- tain castor oil. It is combined with croton oil in veterinary remedies. Castor oil is the only commonly occurring non-volatile expressed oil which is readily soluble in 95 per cent alcohol and in 5 parts 90 per cent alcohol, and this simple test is sufficient to indicate the identity of a sample under examination. It also deviates the plane of polarized light to the right unless it has been heated to 270° C. It is composed chiefly of the glyceride of ricinolic acid. Castor-oil mixture is an emulsified preparation of the oil with acacia flavored with cinnamon and orange flower water. Castor oil is incorporated with magnesium oxide and sold as dry powder. Olive Oil The use of this oil as an internal lubricant and a nutritive agent is on the increase. It is prepared in enormous quantities and marketed in a state of great purity. Besides being sold by itself as a medicinal agent, it is combined with other drugs to furnish a bland medium for adminis- tration and the additional therapeutic action. It will be found combined with apiol; Cascara sagrada extract; copaiba; pennyroyal oil; creosote; oleoresin malefern and kamala, oleoresin saw palmetto; salol, cubeb oleo- resin; santal oil and pepsin, etc. OILS 923 Sweet Almond, Peach, and Apricot Kernel Oils These three oils resemble each other closely in appearance and proper- ties, and may be and probably often are substituted for each other. For all practical purposes their properties are identical, and are closely allied to olive and other bland fixed oils like cottonseed and sesame. Most of these bland oils which are now obtainable in a state of great purity are used as vehicles and for their lubricating and emollient value in inhalants and embrocations. In the early days of the administration of the Food and Drugs Act, the importation of these three oils was the subject of considerable scrutiny, and their absolute differentitation was found to be a matter of difficulty. The practice of mixing one with another was evidently in vogue, and the actual determination of the composition of such a product was practically impossible. As with other oils, the only feasible way of showing any dif- ference between them would be to determine the character of the mixed glycerides, and to apply the knowledge gained in examining the suspected samples. At present the dependence on the difference in color reactions given with certain reagents is too uncertain to be used as a final criterion of differentiation. The improvements in the methods of refining oils have advanced to such a degree that it is possible to eliminate many of the impurities to which the color tests were probably attributable. Again the study of oils has developed the possibilities of manipulation, and by simple treatments it is often easy to render an oil incapable of yielding some of the simple tests which a few years ago were sufficient for its identi- fication. Expressed oil of almond is the base of phosphorated oil. Croton Oil Croton oil from the seeds of Croton tiglam is a component of hepatic stimulants and purgative mixtures. On account of its drastic action it is not dispensed by itself, but is combined in small quantity with other laxative and stimulant drugs which are prepared for use in the form of pills and tablets. The combinations are generally of the following types aloes, gamboge, Podophyllum resin, Capsicum and croton oil; aloin, Nux Vomica, Podophyllum resin, gamboge, Veronica virginica, Capsicum, Veratrum viride, calomel and croton oil; Aloes, scammony, myrrh, caraway oil, mercury mass, and croton oil. It is also present in some of the liquid cathartic mixtures combined with Cascara sagrada. It is sometimes employed externally in cases where a strong counter-irritant is desired, and in veterinary practice has proven a valuable remedy for lump jaw. 924 ORGANIC SUBSTANCES Compte * recommends the following identification test: When the pure oil or a mixture with other oils is shaken with twice its volume of absolute alcohol, the clear alcholic liquid poured into a highly concentrated solution of sodium potassium hydroxide and the mixture warmed thirty seconds in a boiling water-bath and allowed to stand, an intense reddish- brown or reddish-violet ring forms at the junction of the liquid. If during the analysis of a laxative mixture, an oily substance is sepa- rated, a few drops rubbed on the under side of the forearm will cause a characteristic eruption if it is croton oil. Cottonseed Oil This oil is obtainable in a high degree of purity, and is being recom- mended as a nutritive, for which purpose it is expected to rival olive oil. It is used as a vehicle for camphor, menthol, and other medicinal agents, and adds to their virtues the additional value of a lubricant in case of sprains and stiffness of the joints. Sesame Oil Sesame oil is employed as a vehicle and a lubricant, and is one of the components of some of the oily preparations extensively advertised for their value as local applications to the mammary and external genital organs and the abdomens of pregnant women. A characteristic test for this oil and which is useful in detecting it in admixture with other oils is obtained by shaking 1 mil with 1 mil of con- centrated hydrochloric acid containing 1 gram of cane sugar, when a rose- red color develops in fifteen minutes, changing gradually to violet. With other fixed oils no coloration develops for nearly an hour, Chaulmoogra Oil This oil has powerful alterative properties, and is used as a remedy for leprosy. Its source was for a time uncertain, but it is now known that the true oil is expressed from the seeds of Taraktogenos kurzii King. Several species of Hydnocarpus, as H. venenata, H. wightiana, and H. anthelmintica, yield oils of similar chemical composition, the oil from the former being known as false chaulmoogra. The oil from Gynocardia odorata, which was considered at one time the source of chaulmoogra, has an entirely different make-up. It is also a liquid, while the true oil is a soft solid below 22°. 1 I. Pharm. Chim., 1916, 14, 38. OILS 925 Chaulmoogra oil is optically active and consists to a large extent of the glyceryl esters of optically active cyclic acids of the general formula, C„H2n-402- Power, 1 who isolated these acids, designated that present in largest amount chaulmoogric acid, C18H32O2. This acid melts 68° with (o)d56°. A small amount of palmitic acid and a phytosterol are present. Gynocardia oil is optically inactive and contains none of the members of the chaulmoogric acid series. It consists of glycerides of linolic acid or isomerides of the same series, palmitic, linolenic, and isolinolenic acids, and a phytosterol, melting 133°. The seeds of Gynocardia contain a cyanogenetic glucoside, gynocardin. True chaulmoogra oil has a high acid value 23-24, while the false oil is low, 4-5. Oil of Theobroma. Cocoa Butter This oil solidifies below 30° C. and has a characteristic odor. It is extensively employed as a suppository base and functionates to a slight extent in the composition of ointments and salves. VOLATILE OILS General Methods for Examination. — Specific Gravity. — To be deter- mined with pycnometer or Westphal balance. Optical Rotation. — To be determined with a polarimeter or saccharim- eter. Polarimeters permit the angle of rotation to be read off in degrees or fractions of a degree of a circle. Saccharimeters set to measure percent- age of sucrose, give readings in terms of divisions of the sugar scale. One division Laurent sugar scale equals .2167° angular rotation D. One division Schmidt & Hansch sugar scale equals .346° angular rotation D. Specific Rotatory Powder. — The rotatory power of an optically active, liquid substance, observed with sodium light, and referred to the ideal density 1, and in the tube having the length of 1 decimeter (100 mm.)., is designated as its specific rotatory power. This is usually expressed by the term (a) D . Since, however, not only the density of an optically active liquid, but also its rotation, is influenced by the temperature, the specific rotation varies with the latter. In stating the specific rotation it is, therefore, necessary to indicate at what temperature the rotation and the density of the liquid have been determined. But for the same 1 Amer. J. Pharm., 87, 1915, 493. 926 ORGANIC SUBSTANCES temperature the specific rotation of a pure, optically active liquid is always a constant number. The temperature used in the text of the Pharmaco- poeia is 25° C, except when otherwise indicated. For saccharimeters the temperature is fixed at 20° C. by international agreement. For calculating the specific rotatory power of an optically active liquid substance, or solution of an optically active solid, the following formulas are of general application : I. For liquid subtances (a) D II. For solutions of solids (a) D = LXd 10000 X a LXpXd or 10000 X a («); LXc For calculating these formulas the determination of the following factors is necessary: a = the angle of rotation of the liquid or solid observed with sodium light; L = the length of the tube in millimeters; d = the density of the active liquid or solution; p = the amount of active substance in 100 parts by weight of the solution; c = the number of grams of active substance in 100 mils of solution. Solubility in alcohol of various strengths and in other solvents. Saponification Value. — This is actually the sum of the acid and ester numbers. The former is the amount of KOH in milligrams necessary to neutralize the free acid in 1 gram of the oil. The latter is the amount used in the saponification of 1 gram. The saponification is conducted in a wide-necked flask of potash glass of 100-mils capacity. A glass tube about 1 mm. in length and passing through a stopper serves as a reflux condenser. About 2 grams of oil are weighed accurately to 1 eg. into such a flask and 10 to 20 mils of the N/.5 alcoholic potash solution are added. Previous to this the oil should be tested for free acid, an alcoholic solution of phenolphthalein being used as indicator. The flask provided with the condensing tube is heated OILS 927 for half an hour on a steam-bath, and after cooling, the contents are diluted with about 50 mils of water and the excess of alkali titrated back with half normal sulphuric acid. Acetylization. — This is a measure of the alcohols of the Formulas GoHigO and Ci H 20 O. For the quantitative acetylization 10 to 20 mils of the oil, mixed with an equal volume of acetic acid anhydride and 1 to 2 grams of dry sodium acetate, are boiled uniformly from one to two hours in a small flask provided with a condensing tube which is ground into the neck of the flask. After cooling, some water is added to the contents of the flask and then heated from one-quarter to one-half hour on a water-bath, to decompose the excess of acetic acid anhydride. The oil is then separated in a separating funnel, and washed with soda solution and water until the reaction is neutral. Of the acetylized oil dried with anhydrous sodium sulphate 2 grams are saponified according to the method described above. The amount of alcohol, based on the original unacetylized oil, corresponding to the saponi- fication number, can be found by the formulas below. For the calculation the following formulas may be used; 196Xsapon. No. , 1. - — ^ = per cent of ester 56 For the Alcohol, ^ 2 . 154Xsa P on - No - CioHisO 3. 56 a X 15.4 £-(aX0.042) = per cent of alcohol = per cent of alcohol in original oil. For the Alcohol, C10H20O , 198Xsapon. No. , 1. =^ = per cent of ester 00 ' 156Xsapon. No. • . , , , 2. - — ^ = per cent of alcohol 3. 56 aX15.6 = per cent of alcohol in original oil. S - (a X 0.042) a = mils of normal KOH used. S = grams of acetylated oil used for the saponification. 928 ORGANIC SUBSTANCES SUMMARY OF CONSTANTS OF THE MORE IMPORTANT VOLATILE OILS Oil Bitter Almond Anise Star Anise Fennel Caraway Coriander Sandalwood Eucalyptus Orange Cajuput Clove Cassia Chenopodium Cubeb Juniper Lavender Lemon Peppermint Spearmint Nutmeg Pimento Pine Needle (Pinus pumilio) Rosemary Sassafras Mustard Turpentine Thyme Copaiba Pennyroyal (American) Pennyroyal (European. Savin Tansy Specific Gravity at 25° C. 1.038-1.060 .978- .988 .980- .990 .953- .973 .900- .910 .863- .875 .965- .980 Variable depending on species .905-. 925 .842- .846 .912- .925 1.038-1.060 1.045-1.063 .955- .980 .905- .854- .875- .851- .896- .917- .859- 1.018- Optical Rotation in 100-mm. tube .925 .879 .888 .855 .934 .924 .048 .853- .869 .894- .912 1.065-1.077 1.013-1.020 .860- .870 .984- .930 See under drug .920- .935 .930-. 960 at 15° C. .903- .923 .925- .940 Inactive or not over +0° + 10° to -2° 0° to -12° + 12° to +24° +70° to +80° + 8° to +13° -15° to -20° Variable usually laevo +91° to +98° -4° -1°10' + l°to - 1° -4° to -10° -20° to -40° 0°to -15° -4° to -10° +57° to +64° -23° to -35° -38° to -55° +12° to +30° 0° to -4° -3° to -10° -9° to +18° +3° to +4° Inactive Variable Slightly laevo + 18° to +22° + 17° to +23° +40° to +60° +30° to +45° 10 ] Oil of Bitter Almonds The discussion of this oil will be found in the section devoted to Cyano- genetic Glucosides. Oils of Anise and Star Anise These oils are obtained from the fruits of plants belonging to entirely different families. The anise plant Pimpinella anisum belongs to the Umbelliferse, while the species of Illicium which yield the star anise oil OILS 929 belong to the Magnoliaceae. Both oils contain anethol as their most important and valuable constituent, there is also a smaller quantity of the isomeric methyl chavicol. The two oils can be distinguished from each other only by odor and taste. Anise oil is a colorless, highly refractive liquid which solidifies to a snow-white crystalline mass, melting 15-19° C. The solidification point of a sample of oil furnishes very good indication of the quality of the prod- uct, and may be determined as follows: Transfer a small quantity of the oil to a test-tube and surround it with ice water or chipped ice, or a mixture of ice and salt. Insert a thermometer and allow it to remain undisturbed until the temperature has fallen to about 5° below the normal congealing point of the oil (in the case of star anise this is about 15° C. and the fennel about 3°). Then induce crystallization by stirring with the thermometer, removing the tube from the bath and continuing until solidification takes place. The highest temperature reached during the crystallization is regarded as the congealing point. Anise oil has been reported adulterated with fennel oil, turpentine, cedar wood oil, copaiba, and gurjun balsam oil, alcohol, spermaceti, fixed oils. The presence of these adulterants is readily detected by a determi- nation of the physical properties. Fennel oil and its stearoptene are the common adulterants, but they cause a dextro rotation and are easily detected. Pure anise oil undergoes oxidation if carelessly stored or exposed to the fight, its specific gravity increases and its tendency to solidify disappears. Star anise oil is a colorless or yellowish, highly refractive liquid, con- gealing between +14 and +18° C, and containing from 80-90 per cent of anethol with probably some methyl chavicol, and two terpenes, d-pinene and £-phellandrene, making up the balance. This oil often replaces the oil from Pimpinella in medicinal prepa- rations, but because of the amount in which it occurs and because of the modifying influence of the other constituents, no one could assert with any certainty as to the identity of the oil in any given mixture. The chief use of these oils is for flavoring purposes, and as this character- istic is largely due to the anethol it matters little which one is present. Fennel Oil Fennel oils vary in their composition and consequently in their odor and flavor, but the ordinary oil of commerce contains from 50-60 per cent of anethol, fenchone, d-pinene, dipentene, and possibly other constituents. It is a colorless or slightly yellow liquid with a characteristic odor and taste, and solidification point of +3 to +6° C, rotation +12 to +24°- This oil comes from Lutzen, Roumania, Moravia, and Galicia. 930 ORGANIC SUBSTANCES Sweet or Roman fennel oil solidifies +10 to +12°, rotation +7 to + 16°. Macedonian fennel oil solidifies +7 to +12°, rotation +5 to + 12°. Both these oils contain no fenchone. Indian fennel oil contains both anethol and fenchone, melting-point +8°, rotation +21°. Japanese oil contains the characteristic constituents, solidifies +7°, rotation +10 to +16°. Wild bitter fennel oil of France, Spain, and Algiers rotates +48° and consists principally of a terpene. Caraway Oil Caraway oil is a colorless, highly refractive liquid, becoming yellowish in time, with a characteristic odor and spicy taste. Its rotation is +70 to +80°. It is composed of carvone and d-limonene in about equal parts, and the carvone may be readily determined by the method described on page 607. Coriander Oil Oil of coriander is a colorless or slightly yellow liquid, rotating +8 to +13° and soluble in 3 parts of 70 per cent alcohol. It contains d- linalool (coriandrol) and about 5 per cent of d-pinene with other constit- uents to which the characteristic flavor is due. It is often adulterated with turpentine and orange oil, both of which modify the rotation and the rotatory power. Sandal-wood Oil There are several species of Santalum which yield oils, but the oil used for medicinal purposes is obtained from the wood of S. album, a medium-sized tree growing in India. The oil was formerly distilled in the East in large quantities, but owing to the fact that it was almost impossible to prevent adulteration, the users of the drug finally adopted the expedient of importing the wood and distilling their own oil. At the present time all pharmaceutical manufacturers of any pretensions have their own plants for distilling sandal-wood oil. The oil is used principally for venereal diseases, and is dispensed in soluble elastic capsules either by itself or combined with copaiba oil or oleoresin cubeb, oleoresin matico, creosote, eucalyptol, salol, pepsin, oleo- resin saw palmetto, methylene blue, or cinnamom oil. Pill and tablet formulas contain the same remedial agents, also ferrous sulphate, turpen- tine and methyl salicylate. Oil sandal-wood or an extract is combined with saw palmetto and corn silk in elixirs of the sanmetto type. OILS 931 The medicinal value of this drug is due to the santalol content, which according to our standard should be no lower than 90 per cent. The santalol is determined in the same way that menthol is determined in peppermint oil, page 557. The formula for calculating the percentage follows : AX11. 11 PerCent B- (AX 0.021) A is the difference between the number of mils of N/2 sulphuric acid required in the titration and the number of mils of N/2 alcoholic potash originally taken; and B is the weight of acetylized oil taken. Nelson * has described a procedure for the identification of some of the volatile oils more commonly occurring in medicinal preparations. In case volatile oils are used merely as flavoring agents their identi- fication is not so important, and they will be present in small quantity. But if used for their medicinal or antiseptic effect it will be desirable to obtain as large an amount as possible for the examination. A liberal sample of the preparation, neutralized if acid or alkaline, is submitted to steam distillation and the undissolved oily layer separated from the dis- tillate. The physical constants of the volatile oil mixture are first determined. The density is taken with a small Sprengel tube. The optical rotation and index of refraction are determined, and the boiling temperature is taken, keeping the fractions separate for each 10° difference and noting the amount and odor of each fraction. This will often afford a clue to the nature of the mixture and perhaps direct attention to some of the com- ponents. Aldehydes (and some Ketones) Separation. — The oil (or a suitable fraction) is shaken with an equal volume of a saturated solution of sodium hydrogen sulphite in a separatory funnel and allowed to stand with occasional shaking for from eight to twelve hours. If crystals separate they are filtered off; the aqueous layer is separated and the crystals added. To this solution add sufficient sodium carbonate to neutralize the acid sulphite, and distill with steam. Aldehydes will pass over into the distillate and will usually be recognized by their odor. Benzaldehyde will indicate oil of bitter almonds; cinnamic aldehyde, oil of cassia; pulegone, oil of pennyroyal; methyl nonylketone, oil of rue; thujone, oils of tansy, wormwood, or sage. (The last three are ketones which react like aldehydes with sodium hydrogen sulphite.) 1 J. Amer. Pharm. Assn., 6, 1917, 543. 932 ORGANIC SUBSTANCES Aldehydes: Identification Benzaldehyde: Liquid, b.p. 733 mm. 177°; d. 15°/15°, 1.050-1.055; m.p. of semicarbazone, 214°; easily oxidized to benzoic acid. Cinnamic aldehyde: Liquid, b.p. 252°; di5°, 1.054-1 058; m.p. of semicarbazone, 208°; oxidized by cold potassium permanganate to benz- aldehyde and benzoic acid. Citral: Liquid with lemon-like odor; b.p., 228-229°; m.p. of citryl /3-naphtho cinchoninic acid, 200°. Aldehydes: Determination Aldehydes and certain ketones (pulegone, carvone) can be estimated by the neutral sulphite method of Burgess. 1 A saturated solution of sodium sulphite is prepared, and, if acid, is neutralized with a solution of sodium hydrate until a faint pink color is permanently maintained with phenolphthalein. To 50 mils of such solu- tion 25 mils of the oil are added, and two drops of an alcoholic solution of phenolphthalein. The whole is then heated on a water-bath to nearly boiling-point, constantly shaking. A deep-red color almost at once appears, which shows that the action has commenced. A few drops of sulphurous acid are then cautiously added, and this is continued until no further color is produced after a further addition of SO2. The oil is then measured. The obvious advantage of this method is that the end of the reaction may be ascertained to a certainty, while the above bisulphite method depends on the continual shaking for a period of not less than one hour. Phenols: Separation The oil left in the separatory funnel after treatment with sodium hydrogen sulphite, is shaken with two or three times its volume of a 5 per cent solution of potassium hydroxide. After the undissolved oil has separated the aqueous layer is filtered through a wet filter and a slight excess of dilute nydrochloric acid is added. A turbidity at this point will indicate the presence of phenols. Methyl salicylate separates with the phenols. If the odor indicates the presence of methyl salicylate take up the sepa- rated phenols in a little ether; separate th^. ether solution and transfer it to a small flask ; add from 5 to 10 mils of 5 per cent potassium hydroxide solution and warm on a water-bath under a reflux condenser to saponify the ester. Then pass in carbon dioxide to saturation and extract the 1 J. Soc. Chem. Ind., 1901, 1179. OILS 933 phenols (free from methyl salicylate) with ether. Acidify the aqueous solution and extract with ether; if methyl salicylate is present a residue of salicylic acid will be left on evaporating the ether, which can be identi- fied by its melting-point and by the violet color its solutions give when treated with ferric chloride solution. If methyl salicylate is not present the saponification is omitted. Evapo- rate the ethereal solution containing phenols at room temperature. The phenols which may be encountered include thymol and carvacrol (from oil of thyme), eugenol (from oil of cloves), and diosphenol (from oil of buchu). Observe whether the separated phenol shows any tendency to crystallize (thymol, diosphenol). Thymol and diosphenol may be sepa- rated from the more " acidic " phenols as follows: Dissolve the mixture in 5 per cent potassium hydroxide solution and distill with steam. Thymol and diosphenol will come over from the alkaline solution while ordinary phenol and most of the eugenol will remain in the distilling flask and can be recovered with ether. Phenols: Identification Thymol: Crystalline, m.p. 50.5-51.5°. Identify by U. S. P. test (greenish-blue color on adding one drop each of sulphuric and nitric acids to its solution in glacial acetic acid). Carvacrol: Liquid isomer of thymol, odor like thymol. Diosphenol: Crystalline, m.p. 83°, peculiar minty odor. With alcoholic ferric chloride its alcoholic solution gives a dark-green color. Its solutions reduce ammoniacal silver nitrate and Fehling's solution. Eugenol: Liquid, odor of cloves, m.p. of benzoate, 69-70°. Its alco- holic solution gives a blue color with ferric chloride. Phenols: Determination The shrinkage in volume on shaking a measured quantity of the oil with 5 per cent sodium hydroxide solution will indicate the proportion of phenols present. Ketones: Separation The oil remaining after the extraction of aldehydes and phenols is now to be used for the separation of ketones. Advantage is taken of the prop- erty which ketones have of combining with semicarbazide to form crys- talline, more or less difficultly soluble, and difficultly volatile semicar- bazones. From \ to 1 gram of semicarbazide hydrochloride and an equal amount of sodium acetate are dissolved in the least possible amount of water. The oil or its fraction (not over 5 mils) is added and enough 934 ORGANIC SUBSTANCES alcohol is stirred in to give a clear solution. (Some NaCl may be pre- cipitated.) Let the mixture, which should be in a small stoppered flask, stand twelve to twenty-four hours and then dilute with water. If much ketone is present the oil which separates will soon crystallize more or less com- pletely. If crystals separate, filter. In any event separate the oil, trans- fer it to a distilling flask, and distill with steam until the volatile oil is removed. If any ketone is present a crop of crystals should now separate from the residue left in the distilling flask if it is cooled and shaken. Filter off the crystals in a Buchner funnel and unite with any that may have separated previous to distillation. To recover the ketones from their semicarbazones, transfer the semi- carbazones to a saponification flask, reserving a portion for melting-point and other determinations. Add from 5 to 10 mils of 25 per cent sulphuric acid, stopper the flask, and heat on the steam-bath until the crystals are decomposed. If camphor was present alone or in preponderating amount, it can be seen sublimed into the neck of the saponification flask. Cool and open the flask and note the odor. Ketones: Identification Carvone: Liquid, from caraway and spearmint oils, b.p. 230-231°; m.p. of oxime, 72°. Pulegone: Liquid, from oil of pennyroyal, minty odor, b.p. 222-223°; m. p. of semicarbazone, 168°. Methone: Liquid, from peppermint, pennyroyal, and buchu oils, minty odor, b.p. 207-208°; m.p. of semicarbazone, 184°. Camphor: Ciystalline, from camphor and rosemary oils, m.p. 175- 176°; m.p. of semicarbazone, 236-238°; m.p. of oxime, 118-119°. Thujone: Liquid, from the oils of thuja, wormwood, tansy and sage, peculiar odor like wormwood, b.p. 200-201°; m. p. of thujone semicar- bazone, 186-188°; m.p. of a-thuj one semicarbazone, 174-175°. Methyl nonyl-ketone: Liquid, from oil of rue, odor like oil of rue, b.p. 226°, m.p. +13.5°; m.p. of semicarbazone, 123-124°; m.p. of oxime, 46-47°. Ketones : D etermination The total quantity of ketones and aldehydes present can be estimated by the hydroxylamine titration method, page 607. This method will include those ketones which do not react with sodium sulphite or sodium hydrogen sulphite. OILS 935 ALCOHOLS, ESTERS, ETHERS, AND OXIDES The volatile oil remaining unacted on by the previous methods of treat- ment may contain alcohols (as menthol, sabinol, santalol, borneol, and terpineol), esters (as menthyl acetate, and bornyl acetate), and phenol ethers (as methyl chavicol, safrol, anethol, and apiol), or oxides (as cineol). Previous to the further examination of the oil it should be saponified by boiling with an excess of alcoholic potassium hydroxide in order to decompose any esters present. The alcoholic solution is then diluted with sufficient brine to precipitate the oil completely, and the brine solution can be used for the identification of organic acids derived from esters. There is no good general method for separating the alcohols as a class, and the further examination will therefore be governed by the judgment of the analyst as to what alcohols are likely to be present. The primary alcohols, such as geraniol, can be separated by the cal- cium chloride compounds or as acid phthalic esters, provided they are present in sufficient amount (at least 25 per cent of the mixture). The conversion of alcohols into esters difficultly volatile with steam will be successful in some cases. Thus by heating menthol with benzoic anhydride for two hours at 160-170° menthyl benzoate is formed, and by distilling the mixture with steam the ester, being less volatile, remains in the distilling flask, is separated, and the menthol recovered by saponifying. The same method is, of course, applicable to any of the more stable alco- hols provided they are esterified under these conditions and give benzoates slightly volatile with steam. The identification of the tertiary alcohols is even a more difficult matter, as they are more or less dehydrated on heat- ing with acid anhydrides, but they are not often encountered in a medici- nal preparation. When obtained in fairly pure form the alcohols may be characterized by the melting-points of their phenyl urethanes. Sabinol is the alcohol occurring in oil of savin, and since this oil is frequently employed as an abortifacient it should not be overlooked. The best chemical method for identifying sabinol consists in oxidizing it by means of potassium permanganate to a-tanacetogen dicarboxylic acid (m.p. 140°). Safrol may be found in the higher boiling fractions of the oil, its boiling- point being 233°. The characteristic odor of safrol will serve to direct attention to it, and it can be identified by its oxidation product, a-homo- piperonylic acid, which melts at 127-128°. This is obtained by the oxida- tion of safrol with potassium permanganate. Another phenol ether which may be encountered in medicinal preparations is apiol. This boils at 294°, and will therefore be found in the last fraction of the oil. Apiol has a faint parsley odor. On boiling with alcoholic potassium hydroxide apiol is converted into isopapiol, which melts at 55-56°. Tri-brom apiol 936 ORGANIC SUBSTANCES melts at 88-89°. Unless present in relatively large amount its identi- fication, on acccount of its faint odor, is very difficult. Cineol (b.p. 175°) is separated in the first fractions of the oil. Its odor, which suggests eucalyptus oil, may direct attention to it if there is not too much interfering material. Cineol is an important constituent of eucalyptus and cajuput oils and is often used in medicine in pure form, being more commonly known as eucalyptol. It combines with phosphoric or arsenic acid giving unstable crystalline compounds from which cineol can be recovered by adding warm water. Its iodole compound (m.p. 112°) is characteristic, but rather difficult to prepare from impure cineol. Sulphur Compounds, Mustard Oils The esters of isothiocyanic acid, characterized by their penetrating odor, constitute a special group of sulphur compounds. Volatile mustard oil obtained from black mustard, Brassica nigra, is mainly allylisothiocyanate, and as this boils at 151° it will be found in the first fraction of the oil and will be recognized by its pungent odor. Part V INORGANIC SECTION CHAPTER XXV METHODS OF IDENTIFICATION The inorganic substances used in the formulas of medicines and phar- maceutical preparations are chiefly salts of ammonium, the alkali metals; of the alkaline earth group with the exception of barium; aluminum, iron, manganese, zinc, cerium, bismuth, lead, mercury, silver, gold, copper, antimony and arsenic. The inorganic acids combined in these salts include sulphuric, carbonic, sulphurous, thiosulphuric, phosphoric, phosphorous, hypophosphorous, boric, iodic, hydrofluoric, hydrochloric, hydrobromic, hydriodic, hydrocyanic, hydrogen sulphide, nitric, nitrous, arsenous, chloric, and permanganic. The organic acids will be acetic, citric, and tartaric. Elemental sulphur, carbon, iodin, phosphorus, iron, and mercury are often employed. In addition to the above there are a number of double salts of inorganic and organic bases with organic acids, and of inorganic bases with organic acids. In testing for any of the chemicals which are included in this group the worker may follow some wellrecognized scheme of qualitative analysis such as that detailed by Newth in his " Manual of Chemical Analysis," Noyes' " Qualitative Chemical Analysis," or Fresenius. In my work " The Qualitative Analysis of Medicinal Preparations," where I outline a general scheme for the separation of the components of a complex medicine, I show the distribution of both the inorganic and organic substances when the sample is subjected to alcoholic extraction, and the subsequent effect of water on the two large fractions obtained by the alcoholic treatment. Any procedure for analyzing medicine which recommends a preliminary ashing of the sample should be condemned by the analyst. Such treat- ment will destroy many valuable constituents and materially alter the condition of others. On the other hand, it is of course recognized that 937 938 INORGANIC SECTION organic substances often obscure and prevent the characteristic reactions which are essential for the recognition of inorganic substances. For a detailed account of what to do and how to proceed with the complete qualitative analysis of a complex mixture the worker can refer with advan- tage to my directions for manipulating an elixir. PRELIMINARY OBSERVATIONS ON RECOGNIZING INORGANIC CONSTITUENTS The principal inorganic substances or salts of inorganic bases with organic acids used in medicine which are insoluble in water are iodin, mercuric iodide, phosphorus, sublimed sulphur, iron valerinate, bismuth subnitrate, subcarbonate, citrate, and subgailate, cerium oxalate, calcium fluoride, reduced iron, charcoal, red and yellow mercuric oxide, mercurous iodide, mercurous chloride, precipitated sulphur, zinc carbonate, oxide and phosphate, magnesium oxide and carbonate, and a few organic com- pounds of bismuth, aluminum, calcium, and iron. The first three men- tioned are of course soluble in alcohol. In addition to these a medicinal compound may contain calcium car- bonate, sulphate or phosphate, ignited oxides of iron and aluminum, talc, clay, and siliceous compounds, and possibly other heavy inert salts which take part in the architecture of the sample. Of the above substances, all are soluble in hydrochloric acid except iodin, phosphorus, sulphur, charcoal, calcium fluoride, mercurous iodide, mercurous chloride, ignited oxides of iron and aluminum, talc, and clay. Mercuric iodide does not dissolve in dilute hydrochloric acid, but it goes into solution with the warm concentrated acid. Mercurous chloride is converted into mercuric chloride by aqua regia, mercurous iodide is dis- solved, sulphur and phosphorus partly oxidized, and some of the oxides of iron and aluminum dissolved. The organic compounds will be decom- posed to a greater or less degree by boiling with the acids and the metals will be found in both the hydrochloric and aqua regia fractions. The analyst should note carefully any gases evolved, when the unknown product is treated with hydrochloric acid. The carbonates will of course give off carbon dioxide, and if zinc phosphide is present, hydrogen phos- phide with its characteristic odor and inflammability will be apparent. The commoner substances other than those we have already mentioned, which are insoluble in water and acids, are the sulphates of barium, stron- tium, and lead, the silver haloids, silver, and iron cyanides and tin oxide. Their presence in medicinal products would be most unusual. In examining the residue insoluble in acids, the presence of free sul- phur and charcoal is noted without difficulty. Iodin, unless in large amount, will probably have been dissipated by boiling, and recognized METHODS OF IDENTIFICATION 939 by the purple vapors evolved. At this point in the well-ordered schemes a test is made for lead and silver. The former is found by treating the residue with ammonium acetate solution, warming, filtering, and testing the filtrate with hydrogen sulphide. If lead is present, as shown by a black precipitate, the residue, both in the dish and on the filter, must be washed with warm ammonium acetate until there is no reaction for lead. The insoluble portion is then tested for silver by warming with potassium cyanide solution, filtering and testing the filtrate with hydrogen sulphide. If silver is found it must be removed by successive treatments with the cyanide reagent. The residue is then washed clean with yellow ammonium sulphide, the filtrate tested for tin and the insoluble matter on the filter washed with water. Sulphur and carbon should then be burned off in a porcelain crucible and the residue fused in a platinum crucible with a fusion mixture of sodium carbonate 2, potassium carbonate 2, and potassium nitrate 1. After a state of quiet fusion has been attained and the mass cooled, it is leached out with hot water, and in this solution will be found the acids present in the original residue, united to the bases of the flux. Aluminum and chromium might also be present in the aqueous solution in the form of aluminate and chromate. The basic substances present will go into an hydrochloric acid fraction. The aqueous solution should be acidified with hydrochloric acid and evaporated nearly to dryness in order to convert any silicic acid to insoluble silica. A solution obtained by leaching out the silica residue can then be tested for sulphates, fluorides, aluminates, and chromates. The hydro- chloric acid fraction may contain barium, strontium, calcium, iron, alum- inum, and chromium. The separation and identification of these metals can be accomplished by following some well-recognized scheme. CHAPTER XXVI NON-METALS AND THEIR COMPOUNDS HYDROGEN. OXYGEN Hydrogen is not a remedial agent, and neither its recognition or determination are of moment in medicinal analysis. Oxygen is used as a revivifier and for prolonging life, and the strength of the gas in a cylinder is readily determined by transferring the necessary quantity into a gas burette, and then introducing a measured volume into the alkaline pyrogallol tube of an Orsat or other gas apparatus and noting the amount absorbed by pyrogallol. The solution is made by dissolving 20 grams in 200 mils of potassium hydroxide solution (3 to 10), PEROXIDES Hydrogen peroxide, H2O2, is used extensively in medicine, and is now an ordinary household article. The metallic peroxides have come into vogue during recent years, but their adaptability is much more limited than was at first anticipated. Hydrogen peroxide is commonly found in the form of a 3 per cent solution corresponding to 10 per cent by volume of active oxygen. This is the pharmacopceial strength, and is supposed to represent the product sold in packages over the retail counter. It is also sold at 30 per cent strength under the name Perhydrol. The chief uses of hydrogen peroxide solution are for antiseptic, deodo- rant, and styptic purposes. It is used in diphtheria, sore throat, eczema, whooping cough, and other conditions requiring an antiseptic wash; for gonorrhea, wounds, old sores, disagreeable runnings from the nostrils and other parts of the body, as a mouth wash and gargle. It is also used hypo- dermically in cyanide poisoning. In dentistry it is employed for general oral hygiene, as a bleach for the teeth, and for pyorrhea. Hydrogen peroxide is used to a considerable extent as a hair bleach, and in combination with the phenylene and toluylene diamines in pro- prietary hair dyes. Hydrogen peroxide will be found in a great many mixtures which are recommended for mouth washes, gargles, remedies for pyorrhea, and other antiseptic solutions. These preparations often contain other ingredients which are incompatible with peroxide, which soon disappears or becomes 940 NON-METALS AND THEIR COMPOUNDS 941 so weak that it has little or no therapeutic value. For instance, an enthusi- astic manufacturer will include permanganate, glycerin, alcohol, and hydro- gen peroxide in a single mixture, declare them on the label, and then wonder why he is prosecuted for misbranding his product. Cold creams, claiming to possess valuable properties due to the pres- ence of hydrogen peroxide, have been much in vogue, but in most instances the amount of the active ingredient is either negligible or absolutely nil. Of late some of the manufacturers have been substituting sodium per- beroate,and in this way a product is obtained which will yield active oxygen when subjected to the peroxide test. The market was, at one time, flooded with soaps, tooth powders, and pastes featuring a peroxide content, but except in the case of a dry tooth powder containing calcium, magnesium, or zinc peroxide, any peroxide added is soon changed to a more stable body and the peroxide character- istics disappear. Hydrogen Peroxide, U. S. P. According to the specifications the standard hydrogen peroxide solu- tion should contain 3 per cent by weight of H2O2, corresponding to 10 per cent by volume of active oxygen. The U. S. P. method for determining the amount of hydrogen peroxide is as follows : Dilute about 2 grams of Solution of Hydrogen Dioxide, accurately weighed, with 20 mils of distilled water, then acidulate it with 20 mils of diluted sulphuric acid and titrate with N/10 potassium permanganate V. S. It shows not less than 3 per cent of H2O2. Each mil of N/10 potassium permanganate V. S. used corresponds to .0017008 gram of H2O2, or to .0008 gram of oxygen. Each gram of Solu- tion of Hydrogen Dioxide corresponds to not less than 17.6 mils of N/10 potassium permanganate V. S. If it is desired to determine the quantity of oxygen the following pro- cedure will be found satisfactory : The apparatus consists of a 50-mil side-arm distilling-flask closed with a perforated rubber stopper, through which the delivery stem of a glass- stoppered burette has previously been passed. The side arm of the flask is connected to the nitrometer by means of tightly fitting rubber tubing of any convenient length and securely wired at each end to prevent leak- age. The burette is fastened loosely in a Bunsen clamp in such a manner that the burette and flask can be shaken freely on one plane. The nitrom- eter is filled with water, the level adjusted, and the determination made as follows: Place about 1 gram of finely powdered manganese dioxide or potassium permanganate in the side-arm flask and add 10 mils of 10 per cent sulphuric acid. Dilute 10 mils of the hydrogen peroxide solu- 942 INORGANIC SECTION tion to be tested to 100 mils and place a portion in the burette. After sufficient of the solution is run out to fill the delivery stem of the burette fit the stopper (with attached burette) snugly into the neck of the generat- ing flask, and adjust the level of the water in the nitrometer so as to equalize the pressure within the system. Allow 10 mils of the diluted dioxide solu- tion to run slowly into the generator through the burette. After shaking the flask to liberate the dissolved oxygen as completely as possible again adjust the level and note the temperature and pressure. A correction of 10 mils (the volume of solution run into the generator) is subtracted from the reading, and the remainder reduced to 760 mm. pressure and 20° C. temperature. The method recommended in the eighth revision for determining the acidity has been the cause of much criticism, and there seems to be no good reason for the figures obtained by an indirect titration. Warren, Kebler and Ruddiman, 1 who made an exhaustive study of commercial peroxides, state: " Numerous experiments have been made on the determination of the acidity of hydrogen peroxide solutions by the pharmacopoeial and other methods, and it has been found that methyl orange could be substituted with advantage for phenolphthalein if the present pharmacopoeial method is retained. Experience and experiments furthermore show that the free acidity can readily be determined by direct titration, using phenolphthalein as indicator, and there seems to be no good reason for continuing the use of the present pharmacopoeial method." It is only necessary to add to 25 mils of the hydrogen peroxide about 5 or 6 drops of phenolphthalein test solution (U. S. P.) and titrate directly with N/10 alkali to the development of a light-pink color. Under the conditions this method is accurate to .1 to .2 mil. For practical pur- poses the test in the Pharmacopoeia should be stated as follows: If to 25 mils of the solution of hydrogen peroxide 5 or 6 drops of phenol- phthalein test solution are added, not more than 2.5 mils N/10 KOH should be required to produce a pink color (limit of free acid). Acetanilid is often used as a preservative, but the amount is small, usually about .1 per cent. This, of course, must be declared on the label and in order to determine the correctness of the declaration the following method may be employed: In a side-neck flask of 200-mils capacity, place about half a stick of caustic potash or soda (6 to 7 grams). Add about 20 mils of water to dissolve, and then 25 to 30 grams of granulated metallic zinc (the zinc had best be in as fine particles as can be obtained in " granulated " form. There is reason, however, to believe that " zinc dust " is too finely divided for this purpose). Then add a measured amount (not over 50 mils) of UJ. S. Dept. Agri. Bur. Chem Bull. 150, 5. NON-METALS AND THEIR COMPOUNDS 943 the solution to be tested. Connect the flask, on the one side with a flask to supply steam, arranging the tube to deliver steam near the bottom of the solution ; connect on the other side with a condenser. The condenser should deliver into a Peligot bulb tube or some other arrangement by which the distillate is immediately brought in contact with moderately strong hydrochloric acid. Raise the heat on the flask, slowly, and when nearly half of the contents have distilled over, start the steam passing through. The end of the distillation is a matter of guess. When the anilin is coming over in quantity, fumes are to be seen in the receiver, but for the last portions they cannot be seen. When it is judged that all has come over, detach the receiver and catch what comes over later in a fresh receiver or a beaker, and titrate it separately. In conducting the titration, standard bromide-br ornate reagent is run in from a burette until a faint yellow coloration remains, rotating the flask sufficiently to agglomerate the precipitated tribromanilin. To prepare the volumetric bromin solution, dissolve 25 grams of caustic potash in 20 to 40 mils of water, cool, and add liquid bromin until it appears supersaturated. Then dilute to about 200 mils and boil out excess of bromin (judged by the color). Cool, and dilute to 1 liter. This should give a solution of which 1 mil = nearly .01 gram acetanilid. Standardize by means of a solution containing .5 gram acetanilid in 200 mils of water, using 30- to 50-mil lots at a time, treated either by dis- tillation in the manner above given, or by boiling with strong hydro- chloric acid. Either method was found to give the same result with the same amount of acetanilid. The detection of Irydrogen peroxide or a peroxide in admixture with other drugs is not difficult, but their determination usually presents con- siderable difficulty, and quantitative methods are still in the experimental stage. There are three tests for detecting hydrogen peroxide which deserve special mention. 1. An aqueous solution of hydrogen peroxide, even at considerable dilution, will turn a deep-blue color when treated with a few drops of a dilute solution of potassium chlorate followed by a few drops of dilute sulphuric acid, and on shaking with ether the blue color will dissolve in part and color the ether for some time. If the quantity is small the ether should be free from alcohol. This test is not as delicate as some others, but it will show a quantity considerably less than the minimum amount that has any excuse for existing in a product which depends on peroxide for its activity. 2. An aqueous solution of hydrogen peroxide treated with potassium iodide solution and rendered slightly acid with dilute sulphuric acid 944 INORGANIC SECTION becomes yellow, and on shaking with chloroform, the solvent becomes violet owing to the absorption of iodin. This test is probably more deli- cate than the preceding, and in some instances the color will appear only on long standing. 3. Probably the most delicate test is that with titanium sulphate (1 mg. Ti02 to 1 mil). A few mils of this reagent are added to the aqueous solution followed by a little dilute sulphuric acid. Hydrogen peroxide gives a yellow color, the shades depending on the quantity present. This test is extremely delicate, and if negative proves beyond a doubt that hydrogen peroxide is absent. A positive test ought always to be supple- mented b3^ the two others given above, because the influence of various other organic substances has not yet been determined. This test is of course the reverse of the one used for determining titanium in steel. In testing for peroxides in liquids, the volatile substances other than water should be evaporated, any acids neutralized with dilute alkali and the solution again made acid with dilute sulphuric, filtering from any pre- cipitate that may have formed. The solution should then be subjected to the three tests given above. Soaps, cold creams, and tooth pastes are tested as follows : The sample is thoroughly macerated with water and transferred to a Squibb separator of 16 oz. capacity, where it is treated with a slight excess of dilute sulphuric acid. As soon as separation occurs, the clear liquid is filtered into another separator, the magma shaken up with distilled water and the washings filtered into the second separator. This procedure is then repeated and the clear liquid can then be subjected to the above tests. Tooth powders can be handled in practically the same way. The precipitate will consist in large part of calcium sulphate, but this will remain behind on the filter. Assay of Metallic Peroxides One-tenth to three-tenths gram of the material is weighed into a flask, treated with 50 mils of water and 20 mils of dilute sulphuric acid (hydro- chloric acid in the case of calcium peroxide), and then titrated with N/10 permanganate. In the case of sodium peroxide use 1 to 1.5 gram and add gradually to 950 mils of 1 per cent sulphuric acid, making up to 1000 mils with water; 100-mil portions are used for titration. 1 mil N/10 potassuim permanganate = .0036 gram Ca0 2 = .002 gram Mg0 2 = .003786 gram Na 2 2 = .0061 gram Sr0 2 = .0048 gram Zn0 2 NON-METALS AND THEIR COMPOUNDS 945 NITROGEN AND ITS ACIDS Nitrogen as a free element is of no moment in our work, but its identi- fication, as one of the elements in an organic compound, is of considerable importance, and in some instances where a new and totally unfamiliar sub- stance is under examination, its determination will be necessary. The methods for detecting and estimating the percentage of nitrogen in organic compounds are fully described in Gattermann's " Practical Methods of Organic Chemistry," to which the worker is referred. Nitrogen Oxyacids Nitrate of potassium and nitrate of silver are the two salts of nitric acid which have an important place in medicine. The former is a diuretic, and the latter an antiseptic and astringent. The estimation of nitrates follows more conveniently from the determination of the metallic element. The alkali nitrates have a limited use in therapeutics, and amyl and ethyl nitrite, the latter in sweet spirit of nitre, are of considerable impor- tance. The method of determining the nitrite radicle and estimation of the ester has already been given in detail on page 734. Nitrites may be determined by titration with permanganate accord- ing to the equation 5HN02+K2Mn20 8 +3H 2 S04 = 5HN03+K 2 S04+ 2MnS04+3H20. If the reagent is standardized with iron, 4 atoms of iron correspond to 1 molecule of N2O3. For 1 part NO2 at least 5000 parts of water should be present. The sample is dissolved in water slightly acidulated with sulphuric acid, the permanganate added till the oxidation of the nitrous acid is nearly completed, the solution then made strongly acid and finally permanganate is added to light-red coloration. THE HALOGENS AND HALOGEN ACIDS With the exception of iodin, none of these elements by themselves have an extended application in medicine. Bromin water and chlorin water are preparations used to a slight extent where drastic disinfectants are needed, such as in cancerous conditions, foul discharges, boils, and ulcers, smallpox, diphtheria, and venereal disease. The use of iodin is on the increase. It is a popular application in dentistry and nose and throat work, where it functionates as an anti- septic and cleansing agent, and possibly as a tonic. It is used in erysipelas and other skin diseases, in enlarged and scrofulous glands, venereal dis- charges, and in many other conditions requiring an antiseptic. The official liquid preparations of iodin are the tincture, which contains 70 grams of iodin and 50 grams of potassium iodide in 100 mils of alcohol 946 INORGANIC SECTION (95 per cent), and the compound solution, containing 5 grams of iodin and 10 grams of potassium iodide in 100 mils of water. These preparations are often too irritating to the membrane to be used without modification, and hence will be diluted with water or glycerin. Inhalants are made up with a neutral oil base containing different percentages of iodin sometimes up to 2 per cent, with menthol, thymol, eucalyptol, camphor oil of cassia, sassafras, etc. Besides the above-mentioned common methods of dispensing iodin in solution, preparations have recently appeared which contain no iodides or glycerin, but which depend upon hydriodic acid and alcohol to keep the iodin in solution. These solutions are capable of considerable dilution without the precipitation of iodin. Iodin ointments are popular. The iodin is usually dissolved in gly- cerin and potassium iodide, and then mixed with the base. Ammonium oleate mixes readily with iodin and glycerin and ammonium iodide, and proprietary preparations containing these substances in a petrolatum base are widely exploited. Bromin chloride, BrCl, is a reddish-yellow, mobile, volatile liquid, unstable, losing chlorin at 10°. It has been used in cancerous conditions. Iodin monobromide, IBr, and monochloride, IC1, are solids. Iodin penta- bromide, IB15, and tribromide, IBr3, are dark-brown liquids which are employed in dilute spraj^s for diphtheria and other conditions requiring an antiseptic application to the mucous membrane. Characteristics and Qualitative Tests for Elementary Halogens. — Chlorin is well known as a greenish-yellow gas, with a characteristic suffocating odor, and an irritating action on the mucous membrane of the nose and throat. Its solution in water is yellow in color and the addi- tion of a bromide or an iodide, bromin or iodin are liberated, and will dissolve in chloroform with their characteristic color. Chlorin water is a powerful bleaching agent and will decolorize indigo solutions. Bromin is a dark, brownish red, volatile liquid, vaporizing at the ordi- nary temperature. Its action on the membrane of the nose and throat and eyes is powerful, but the effect may be ameliorated by exposing the inflamed parts to the vapors of chloroform. Its bleaching action is less than that of chlorin. It gives a yellow color with starch and its aqueous solution is reddish. It dissolves in chloroform with a reddish-brown color and will liberate iodin from solutions of iodides. Iodin is a solid, steel-like, and shiny in appearance, and readily passes into a deep violet -colored vapor at ordinary temperature, and on heating. It fuses, but will volatilize without melting. It is only slightly soluble in water, but dissolves readily in alcohol and other organic solvents, hydriodic acid, and iodide solutions. Its solution in chloroform is violet deep-purple or almost black, depending on the quantity present. With NON-METALS AND THEIR COMPOUNDS 947 cold starch paste iodin gives an intense indigo-blue color which will dis- appear on heating and again appear on cooling. Quantitative Analysis of Preparations Containing the Free Halo- gens. — Iodin can be titrated directly with N/10 thiosulphate, using starch as an indicator. For assaying tincture of iodin the Pharmacopoeia method recommends using 5 mils, mixed with 25 mils of water, which will require about 27.25 mils N/10 thiosulphate for decolorization. The compound solution of iodin is assayed by weighing 6.3 grams and titrating with the same reagent, which should require about 24.75 mils. 1 mil N/10 Na 2 S 2 3 = .01259 gram iodin In making an assay of the more common iodin mixtures the procedure will depend somewhat upon the nature of the ingredients, which will have to be identified by a previous qualitative examination. The direc- tions here given can be used for a mixture containing free iodin, free hydriodic acid, an iodide, alcohol, and water. Glycerin will not inter- fere with the tests, but no satisfactory method is available for its own estimation except in an approximate manner, and the analyst is referred to that portion of the work which discusses glycerin specifically. If desired a weighed quantity can be made up to a definite volume ctnd aliquots taken for the tests. If the specific gravity is. determined and measurements made at the same temperature the sample may be measured. Twenty-five mils are transferred to a 100-mil graduated flask and made up to the mark. An aliquot amounting to 25 mils is titrated with thiosulphate in order to determine the free iodin, and in the decolor- ized solution any free hydriodic acid is determined by titrating with N/10 alkali. 1 mil N/10 KOH = . 012690 HI. A second aliquot of 25 mils is transferred to a separatory funnel, diluted with water and shaken out with chloroform, if the iodin fails to entirely leave the aqueous liquid, collect the chloroform in another separatory funnel and repeat until decolorized. Combine the solvents and wash with water, discarding sol- vent and returning wash water to the main liquid. Filter and wash. Then neutralize filtrate and washings and concentrate over the steam-bath. Filter if not clear and in the filtrate determine the iodin by precipitating with silver nitrate in the presence of dilute nitric acid. Collect the silver iodide on a tared Gooch, wash thoroughly and weigh. From the total iodin found deduct that due to hydriodic acid and calculate the rest to the iodide salt present. Alcohol must be determined in a separate portion of the original sample. In order to do this proceed as directed for the determination of alcohol in galenical mixtures, page 2, first destroying the free iodin with crystalline thiosulphate and then neutralizing any free acid. 948 INORGANIC SECTION Free iodin in ointments and inhalants of an oily nature can be deter- mined by transferring the weighed sample to a flask possessing a ground- glass stopper and a long air condenser. Alcohol containing 10 per cent potassium iodide is then added and the flask warmed until the ointment has melted, and then gently agitated. If the heat tends to drive the iodin beyond the lower half of the air cooler, introduce a little aqueous potas- sium iodide through the cooler and continue the agitation. Cool, remove the stopper, and transfer alcoholic liquid to a closed flask, washing out flask and residue with alcohol containing potassium iodide. Repeat digestion with alcoholic potassium iodide and then wash out condenser and titrate the solution with N/10 thiosulphate. While the determination in medicinal preparations of free chlorin or bromin is seldom a matter of moment, this may be accomplished by adding an excess of potassium iodide solution and titrating the liberated iodin with thiosulphate. - Each mil N/10 Na 2 S 2 3 = .007936 gram Br = .003518 gram CI. Sulphur Iodide. U. S. P. Assay. — .5 gram of finely pulverized sulphur iodide together with 1 gram potassium iodide is dissolved in 20 mils of water (sulphur separating), not less than 28 mils N/10 Na2S2C>3 should be required for complete decolorization of the mixture using starch as indicator. Assay of Iodin Ointment, L. H. Freed. 1 — Free Iodin. — Carefully clean, dry, and tare a 120-mil Erlenmeyer glass-stoppered flask and accurately weigh into it from 3 to 5 grams of ointment, using a glass rod for trans- ferring it. Add 30 mils chloroform, shake the flask a few minutes until the ointment is apparently dissolved. Then add 30 mils of distilled water, shake, and immediately titrate with N/10 sodium thiosulphate. Potassium Iodide. — Five grams are weighed into an ordinary 250-mil Erlenmeyer flask and attached to a distillation apparatus, using as a receiver a 250-mil glass-stoppered Erlenmeyer containing 1 gram potas- sium iodide dissolved in 30 mils distilled water, and 30 mils chloroform. Allow the end of the condenser tube to dip into this mixture. Make all connections air-tight, using rubber stoppers. Mix 5 mils sulphuric acid with 150 mils of distilled water; add the acid mixture quickly into the flask followed by a few pieces of pumice which have previously been heated to redness and dropped into cold water. Finally, add about 5 grams of ferric alum. Place upon a wire gauze and apply direct flame very slowly at first, until the purple vapors of iodin have all distilled over. The 1 J. Amer. Pharm. Assn., 1915, 4, 621. NON-METALS AND THEIR COMPOUNDS 949 lodin will sometimes condense in the tube and not go down into the receiv- ing flask; if this happens move the flame and allow the liquid to run back into the tube and dissolve the iodin. Replace the flame and continue distillation until an oily substance comes over. Discontinue the dis- tillation by first removing the receiving flask, then remove the flame and wash out condenser tube end with 20 mils water. Immediately titrate with N/10 thiosulphate. The result is the total iodin, from which, after subtracting the amount of free iodin, the quantity of potassium iodide is calculated. i Rapid Method for Separation and Estimation of Iodin. — This method, discovered by Seeker and Mathewson, 1 was first used for estimating iodin in Erythrosine, but it is applicable to other organic compounds, and useful in assaying iodin in inorganic mixtures containing chlorin and bromin. Dissolve .3 to .4 gram of the sample in 5 mils 10 per cent sodium hydroxide, add 35 mils 7 per cent, potassium permanganate, cover with a watch-glass and add 10 mils concentrated nitric acid. Heat on a steam-bath, keeping covered until ail spattering ceases, then remove cover and evaporate to dryness. Treat the residue with 5 mils permanganate and 5 mils nitric acid, and again evaporate. Dissolve the residue in 50 mils water, 5 mils nitric acid, and 40 mils saturated sulphur dioxide solution. Then add excess silver nitrate, boil till sulphur dioxide is expelled, and the silver iodide has flocculated, and filter and weigh the latter as usual. HALOGEN ACIDS Of considerably greater importance in medicine than the elemental halogens themselves are the halogen acids, and more particularly the salts of these acids. There are two general classes of these acids, halogen hydrides and halogen oxyacids. To the first belong hydrochloric, hydrobromic, hydriodic, and hydro- fluoric acids. The free acids, with the exception of hydrofluoric, which boils at 19.5° C, are fuming gases at the ordinary temperature. They dissolve readily in water, and their solutions constitute the different grades and strengths of acids of commerce. Many of the salts of the first three are well-known remedies and they will often be found in the analysis of complex mixtures. The identification of these acids has already been discussed in the general scheme for arriving at the composition of the inorganic constituents of a given product. Hydrochloric acid of the U. S. P. is an aqueous solution of about 31.5 to 32 per cent HC1 gas. Diluted it may be used as an antiseptic, antipyretic, and caustic in fevers, dyspepsia, syphilis, eczema, psoriasis, etc. As a popular remedy it should be anticipated in preparations recommended 1 U. S. Dept. Agri. Bu. Chem. Circ, 65. 950 INORGANIC SECTION for impaired digestion, and it will sometimes be found accompanying all of the digestives and stomachics in tablets and liquid preparations. Chlor- ides of the different metals find application over the entire field of medicine. Hydrobromic acid is marketed in different strengths, but the official acid is the dilute, and contains 10 per cent by weight of HBr. It has a limited use in allaying nervous conditions, especially of an acute or violent nature. The bromides are much more stable and are extensively used in medicine. Hydriodic acid is official in the Pharmacopoeia as a 10 per cent solution, but acid of much greater strength is obtainable. If made accord- ing to the specifications of the standard, the solution will contain a small quantity of hypophosphorus acid and perhaps a little tartaric acid. Its chief use is for the preparation of syrup hydriodic acid, which contains about 1 per cent by weight of HI. Hydriodic acid is used in rheumatism, bronchitis, asthma, syphilis, obesity, psoriasis, eliminating mercury and arsenic from the system, and as a tonic. The metallic iodides are in the aggregate probably the most extensively used chemicals in the field of medicine. Potassium iodide will be found in many of the advertised asthma and hay fever " cures " and in the sarsaparillas. Quantitative Estimation of the Free Acids and Acid Radicles. — The estimation of free hydrochloric acid in aqueous solution may be accom- plished by titrating with standard alkali, and the other halogen acids can also be determined in like manner. The Pharmacopoeia does not direct that either hydrobromic or hydri- odic acid shall be titrated directly with alkali. The former is determined after neutralizing with ammonia, by titrating with silver nitrate, and the latter by an indirect method detailed below. For determining the quantity of halogen in a mixture containing the free acids or an aqueous solution of a chloride, bromide, or iodide, there is no better method than that of precipitating with silver nitrate in presence of an excess of dilute nitric acid, boiling, filtering onto a tared Gooch, and weighing the silver compound. The details of this manipulation are well known to a worker in quantitative methods. It is applicable to com- plex medicines, and may be employed after the removal of organic sub- stances by shaking out procedures, provided, of course, that no halogen acid or compound has been introduced during the manipulation. Before precipitating with silver nitrate the solution should be boiled for ten to fifteen minutes after the addition of concentrated nitric acid. The quantity of the acid added should not be great enough to cause a decom- position of any iodide or bromide. After boiling, the silver nitrate is added, and when the precipitate has agglomerated, it is filtered onto a tared Gooch and well washed with water and finally with alcohol to remove NON-METALS AND THEIR COMPOUNDS 951 organic products of decomposition. From the weight of the silver com- pound the acid or salt can be readily calculated. The determination of the purity of a salt of a halogen acid by the U. S. P. method may be accomplished as follows. A weighed amount of the salt is dissolved in water, the solution treated with 2 to 3 drops of potassium chromate, and then titrated with N/10 silver nitrate until a permanent brownish-red color is obtained. This procedure as applied to the following salts may be summarized. Amount Taken, Grams Made up to Aliquot Mils Mils N/10 AgNOs Purity, Per Cent lmilN/10 AgNOs equals gram HBr 10 3 1 1 0.3 0.5 0.3 1 0.5 0.5 0.3 100 mils neutralize 100 mils 100 mils 100 mils * 50 mils 10 mils 50 mils 100 mils 10 mils 50 mils 10 mils 8 10 10 20 50 10 50 10 10 50 10 10 31.6 18.7 22.5-23.9 24.6-25.85 30-30.8 28.5-30 17.05 33-34.6 27.4-29.4 26-26.8 10 97 99.5 97 97 99 97 99 98 97 97 NH 4 Br NH 4 C1 LiBr .009729 .005311 .008634 KBr. . .011822 KI .016476 NaBr NaCl Nal .010224 .005806 .014878 SrBr 2 +6H 2 0.. ZnBr .017647 .011181 For hydriodic acid and some of the iodides the Pharmacopoeia recommends a different procedure. A weighed quantity in aqueous solution is treated with a known excess of N/10 silver nitrate, 5 mils of ferric ammonium sulphate test solution and 3 to 4 mils of nitric acid free from nitrous fumes. After thorough shaking it is titrated back with N/10 potassium sulphocyanate until a permanent reddish-brown tint is obtained. The application of this method to pharmacopceial chemicals may be noted below. Amount N/10 Taken, Grama Made up to Aliquot, Mil3 AgN0 3 , Mils N/10KSCN lmilN/10 AgNOs equals HI 2.54 50 mils 50 25 not more than 5 mils 0.5% HI Syrup HI. . . 31.73 50 mils 10 8 not over 3 mils 0.2% HI Syrup Fel 2 . . 10 100 mils 15.4 6 not over 1 mil 1.0% Fel, SrI 2 +6H 2 0. 0.5 100 mils 100 25 1.7-3.1 Purity 98% Znl 2 0.5 20 mils 20 35 3.4-4 Purity 98% 952 INORGANIC SECTION HALOGEN OXYACIDS Hypochlorous acid, HCIO, is familiar to the pharmaceutical chemist in the form of its calcium salt known as bleaching powder, and in the form of a solution of its sodium salt, which is called chlorinated soda or Labar- raque's solution. Both of these salts are unstable and readily part with their chlorin even under the influence of carbon dioxide. They also yield chlorin when treated with dilute acetic and mineral acids, and in this way are sharply distinguished from chlorides and chlorates. When silver nitrate is added to a solution of sodium hypochlorite there is a pre- cipitation of silver chloride representing two-thirds of the silver, the balance being dissolved probably as silver chlorate. NaOCl+AgNOs = AgClO-f NaN0 3 3AgC10 = AgC10 3 +2AgCl Sodium hypochlorite solution is usually sold unmixed with any other drug. The Pharmacopoeia directs that it shall contain not less than 2.4 per cent available chlorin. The activity may be determined by trans- ferring .5 to .7 gram weighed out by means of a dropping bottle to an Erlenmeyer flask, diluting with 50 mils of water, adding 2 grams potassium iodide and 10 mils hydrochloric acid and titrating the iodin with N/10 thiosulphate. The solution is used chiefly as a disinfectant and antiseptic in cases of malignant nature, scarlet fever, typhoid, scrofula, syphilis, and where there are foul and offensive discharges. Method of Assay of Calcium Hypochlorite, U. S. P.— Introduce into a stoppered weighing bottle between 3 and 4 grams of the sample and weigh accurately; triturate thoroughly with 50 mils of water and transfer to a graduated 1000-mil flask, adding rinsings and make up to volume. After shaking allow the sediment to settle and decant 100 mils. Add 1 gram KI and 5 mils dilated hydrochloric acid and titrate with N/10 Na2S203. Multiply the number of mils consumed by .3518 and divide the product by to the weight of the sample ; the quotient represents the percentage of available chlorin present. The acids, chloric, HCIO3, bromic, HBrC>3 and iodic, HIO3, differ in stability in the opposite order to that usually shown by halogen compounds. Iodic acid is a comparatively stable solid, but is readily reduced by sulphur dioxide or hydrogen sulphide with liberation of iodin, and it reacts with hydriodic acid, all of the iodin being set free, HI03+5HI = 3Ii20+3l2. This reaction is of value in detecting the presence of an iodate when mixed with an iodide, for by dissolving in water and adding acetic acid the liber- ated acids react and the iodin is set free. The most important medicinal chemical representing this group is NON-METALS AND THEIR COMPOUNDS 953 potassium chlorate. It has an extensive use as a household remedy for sore throat and is also used in diphtheria, stomatitis, and diseases of the mucous membrane. It will be found in aqueous mixtures intended as a spray in nasal troubles, hay fever, asthma, and the like, and mixed with opium extract for hemorrhoids. In the powder form it occurs mixed with other substances as a dusting mixture for wounds and ulcers. Potassium chlorate is often combined with ammonium chloride in throat tablets and with sodium chloride in nasal sprays. Sodium chlorate is also in general use, and magnesium chlorate has a slight use. Having detected the presence of a chlorate in the regular scheme of analysis, and there being no other halogen acid present, the chlorate may be determined by dissolving a weighed sample in water, adding dilute sulphuric acid and a piece of zinc and allowing the reaction to continue for thirty minutes. The solution is then filtered from any undissolved zinc, the filter paper washed and the filtrate neutralized with sodium carbon- ate and the chlorin then determined by precipitation with silver nitrate in the presence of nitric acid. The amount of KCIO3 may be obtained from the factor .8551, NaC10 3 .7445. The determination of the chlorides and chlorates in admixture may be accomplished by weighing out the sample into a graduated flask, dis- solving in water, and determining the chloride in an aliquot by precipi- tating with silver nitrate. An aliquot of the same quantity is then treated with zinc and sulphuric acid as described above and the total chlorin determined. The silver nitrate representing the chlorate is then easily figured and calculated to the chlorate. Bromates are unimportant medicinally. Iodates of sodium and potas- sium are used sometimes both as substitutes for chlorates and iodides. They are used externally in trachoma, corneal infiltration, and torpid ulcers and internally for acute and chronic muscular rheumatism. Iodin pentoxide, I2O5, so-called "Anhydrous Iodic Acid," is a' white powder soluble in water with formation of IH2O3. It is used internally in gastric hemorrhage and vomitings and externally in nose and throat work and venereal disease. It is a powerful oxidizing agent. Iodic acid is a colorless crystalline powder soluble in water and used medicinally in aqueous solution for the ailments mentioned above. Perchloric acid, HCIO4, in the form of its potassium salt is used as an antipyretic and antiperiodic in pernicious fevers and malarial conditions. The perchlorates are more stable than the chlorates. Sulphuric acid liberates the free acid, which is a colorless, fuming, corrosive, volatile liquid. No yellow color appears in this test as is the case with chlorates. Hydrochloric acid has no action on perchlorates, which is in sharp dis- tinction from its action on chlorates. 954 INORGANIC SECTION ORGANIC HALOGEN COMPOUNDS Organic compounds of iodin are commonly employed as medicinal agents. The iodin in these substances can often be determined by boiling a solution of the substance with dilute nitric acid and then precipitating with silver nitrate, filtering and thoroughly washing with alcohol and then water (see Emery's Method for Determining Iodin in Antipyrin periodide, described on p. 801. It often happens that this procedure will not suffice to bring the iodin into proper condition for precipitation with silver nitrate and in the event of such a contingency recourse must be made to a Carius combustion. Again it will be simply necessary to saponify with alcoholic potash (ethereal salts), see chloroform and iodoform, p. 742-744. The determination of chlorin and bromin in organic combination follows the same general procedure. SULPHUR AND SULPHUR ACIDS The Pharmacopoeia recognizes three forms of sulphur, the sublimed or flowers of sulphur, the precipitated or lac sulphur, often impure from the presence of calcium salts, and the washed. One of the commonest sul- phur preparations is the combination with potassium bitartrate. Sulphur is employed in atonic gout, chronic rheumatism, chronic catarrh, asthma, piles, and cutaneous affections, and is dispensed usually in the form of lozenges and tablets. Sulphur is insoluble in water and precipitated sulphur does not dissolve in alcohol. Sublimed sulphur is somewhat soluble in alcohol. The iden- tity of the element is determined by its burning with a pale-blue flame, producing sulphur dioxide, which has a characteristic odor and turns potassium iodate starch paper. When heated in a test-tube, sulphur melts and boils off as a brownish-yellow vapor, which condenses to brown drops on the moderately hot parts of the tube, and as a yellow sublimate on the upper and cooler part. Nitric acid oxidizes sulphur to sulphuric acid with evolution of nitrogen peroxide. When elemental sulphur is combined with substances soluble in water, it is readily determined by treating the ground substance with water, filtering through a Gooch, drying, and weighing the residual sulphur. When sulphur is combined with charcoal or other substances insoluble in water or carbon bisulphide, the sample should be ground and extracted with carbon bisulphide, the solvent collected in a tared dish, evaporated, and the residue weighed. Free sulphur in complex formulas containing vegetable drugs can be determined by oxidation with nitric acid in a Carius tube. The sample should be ground and extracted with hydrochloric acid, filtering through a Gooch, and the residue is then transferred to the tube. Sufficient fuming NON-METALS AND THEIR COMPOUNDS 955 nitric acid is added to cover the material, the open end of the tube drawn out to a thick-walled capillary and sealed off. The tube is introduced into a Carius combustion furnace and heated from four to ten hours, raising the temperature gradually from 100 to 300°. After cooling in the furnace, the pressure is relieved by applying a flame to the capillary. The end of the tube is broken off, the contents washed out, the diluted liquid filtered, and the sulphate precipitated by barium chloride. The barium sulphate is filtered, washed, ignited, and weighed. Hydrogen Sulphide Hydrogen sulphide water is occasionally employed as a remedy in certain types of tuberculosis. Barium sulphide is a depiliatory and will be found mixed with zinc oxide and starch. Sulphurated lime, which is a mixture of calcium monosulphide and sulphate, is also used as a depili- atory and as an alterative. It will be found in pills and tablets and is employed in measles, scarlet fever, erysipelas, influenza, acne, and furun- cular eruptions. The determination of sulphide sulphur in substances of this nature can be made by the method of assay for calcium sulphide in the Pharma- copoeia. Introduce about .2 gram of calcium sulphide, accurately weighed, into a glass-stoppered bottle or flask; add 50 mils of distilled water, mix, and quickly introduce 30 mils of a 10 per cent ammonium chloride solu- tion and immediately stopper the flask. Agitate the contents for a few minutes, add quickly 20 mils of a 10 per cent cadmium chloride solution, immediately insert the stopper and again agitate well for a few minutes. Then add 5 mils of acetic acid, heat the mixture on a water-bath for fifteen minutes, decant the supernatant liquid through a filter, agitate the remain- ing precipitate with 10 mils of diluted acetic acid, transfer the precipitate to the filter, and wash with 10 mils of diluted acetic acid. Return the filter and precipitate to the original flask, add 50 mils of N/10 iodin V. S. and 20 mils of a mixture of equal volumes of hydrochloric acid and water. Stopper the flask and agitate it vigorously for a few minutes, and then titrate the excess of iodin with N/10 sodium thiosulphate V. S. It shows not less than 55 per cent of CaS. Each mil of N/10 iodin V. S. used corresponds to .003607 gram of CaS. Each gram of crude calcium sulphide corresponds to not less than 152.5 mils of N/10 iodin V.S. SULPHUR OXYACIDS The sodium and some of the potassium salts of the sulphur oxyacids are used quite extensively in medicine. Sulphate of magnesium is a well- 956 INORGANIC SECTION known household remedy. Certain proprietary sulphur remedies consist of mixtures of the alkali and alkaline earth salts of one or more of all of the sulphur acids and were formerly labeled " Soluble sulphur." To dis- tinguish the several combinations of sulphur acids a solution may be examined as follows: The sulphide is separated by agitating the solution with lead or cadmium carbonate and filtering. Barium chloride is then added to the filtrate and the sulphate and sulphite precipitated. After filtering, the filtrate is treated with hydrochloric acid and the thiosulphate will be decomposed with precipitation of sulphur and evolution of sulphur dioxide. The mixed sulphates and sulphite of barium are then treated with hydrochloric acid which will dissolve the sulphite, and on filtering and adding chlorin water to the filtrate the sulphurous acid will be oxidized to sulphuric acid with precipitation of barium sulphate. The sulphur as sulphate in an unmixed medicinal chemical is usually determined by the well-known procedure of precipitating with barium chloride in presence of hydrochloric acid, filtering onto a Gooch and weigh- ing or by ignition on a filter paper. Sodium sulphite is a salt which, on standing, will gradually oxidize to sulphate. The purity of a sample is determined by dissolving in recently boiled water and titrating with iodin in presence of hydrochloric acid. As a remedy it is employed as a germicide and anti-fermentative and should be looked for in tablets recommended for sour stomach and indiges- tion. Galenicals of this class often contain Nux Vomica and ipecac, and aqueous solutions prepared directly cannot be titrated with iodin. Sodium sulphite is sparingly soluble in alcohol and hence if its determination is desirable an aqueous solution of the tablet is filtered, oxidized by boiling with chlorin or bromin water, and the sulphate precipitated with barium. In case a water-soluble sulphate is simultaneously present, the filtered aqueous solution is made up to a definite volume, the sulphate determined in an aliquot and a second portion subjected to the chlorin oxidation. Thiosulphate of sodium is an antiseptic and germicide, and is employed in parasitic skin diseases, sore mouth, diphtheria, diarrhea, typhoid fever, dyspepsia, etc. The purity of a sample is determined by titration with iodin in neutral solution. 2Na 2 S203+l2 = 2NaI+Na2S406. If this salt occurs in admixture and titration is not feasible, it may be converted into the sulphate by means of chlorin or bromin water and then determined. PHOSPHORUS AND ITS ACIDS Phosphorus, as an element, is a component of a class of medicines known as lost-manhood restorers, and will be found in pills, tablets and elixirs alone and combined with Nux Vomica, damiana, cantharides, coca cinchona alkaloids, iron salts, aloes, Digitalis, belladonna, Cannabis sativa, NON-METALS AND THEIR COMPOUNDS 957 zinc, and other valerianates, opium alkaloids, ipecac, and metallic phos- phides. It is also combined with cod-liver oil in capsules. The analyst who undertakes the examination of galenical preparations will often meet with phosphorus in combination with one or more of these drugs. This element is also found to a considerable extent in rat poisons, and its detec- tion is of considerable importance in toxicological investigations. Phosphorus used in medicine is the yellowish stick form. Its detection is simple, especially when it occurs in elixirs, for it distills when the mix- ture is boiled, and in making an alcohol determination it will be found in the distillate. It is good practice, after determining the specific gravity of the distillate, to add a slight excess of chlorin water and allow the solu- tion to stand an hour or more. If phosphorus is present it is oxidized to phosphoric acid, and on boiling off the excess of chlorin and adding ammonium molybdate a yellow precipitate will appear. If phosphorus is suspected in pills or tablets it can be dissolved by triturating the ground material with alcohol. The alcoholic solution is filtered, diluted with water, and subjected to distillation, whereupon the phosphorus will appear in the distillate. In the general scheme of qualita- tive analysis a small portion of the alcoholic extraction should be reserved for the above test. Ewe and Vanderkleed 1 have described a simple method for determin- ing free phosphorus in rat pastes, which is applicable to tablet and other preparations containing the substance in the elemental state. The sample amounting to about a gram in the case of a rat paste, and considerably more of a galenical is placed in a distilling flask connected with a carbon dioxide generator and a condenser, the condenser being connected with a 300-mil Erlenmeyer flask containing 50 mils of 3 per cent silver nitrate solution. The Erlenmeyer flask is connected in series with two U tubes containing 3 per cent silver nitrate solution. All connections exposed to the phosphorus should be of glass or cork covered with plaster of paris. A stream of carbon dioxide is passed through the apparatus for twenty minutes and the joints examined for leaks with flexible collodion; 125 mils of cold, freshly boiled distilled water containing 2 mils of sulphuric acid are introduced into the flask containing the sample by means of the tube which leads to the carbon dioxide generator. The current of gas is con- tinued, and the flask gently heated until, after about three hours, prac- tically all of the liquid has been distilled into the silver nitrate solution. The condenser is allowed to become hot from the distillation, and the generator is disconnected and the flame removed. All of the silver nitrate solution is then collected in the Erlenmeyer flask, using nitric acid to dis- solve any black precipitate in the U tubes. Fifteen mils of nitric acid are added to the mixture, boiled for five minutes and a slight excess of hydro- 1 J. Amer. Pharm. Assn., 3, 1914, 1684. 958 INORGANIC SECTION chloric acid to precipitate the silver. After boiling until the silver chloride separates out completely, the flask is cooled and the liquid filtered and concentrated to 150 mils. It is then cooled, excess of ammonia added, followed by nitric acid, the phosphate precipitated by molybdate, and the determination completed by the customary procedure. Estimation of Yellow Phosphorus. — Engelhardt and Winters 1 give the following method: The phosphorus, deprived of any oxidation products by scraping, is dried in an atmosphere of carbon dioxide, weighed, dis- solved in chloroform free from air, and made up to volume, the solution adjusted so that 10 mils corresponds to .03656 gram of phosphorus. Ten mils of the solution are received in a bottle with 15 mils 10 per cent copper nitrate from which the air had been expelled by heating; the air in the bottle replaced by carbon dioxide, and the mixture shaken for one-quarter hour. Hydrogen peroxide is added, the mixture shaken until the black color of the copper phosphide disappears, the aqueous solution separated, the chloroform washed twice with 15 mils water, the combined aqueous solution and wash-waters after the addition of nitric acid evaporated to 5 mils testing from time to time for unoxidized phosphorous acid. When oxidation is complete the phosphoric acid is estimated in the aqueous liquid as mangnesium pyrophosphate. Phosphorus Resin. — Four grams of the resin (accurately weighed) are dissolved in 50 mils air-free chloroform in a separator, 20 mils air-free water added, the air in the separator replaced by carbon dioxide and the mixture shaken for one-quarter hour. An aliquot of the chloroform solu- tion is then drawn off and treated with copper nitrate as given above. Phosphorus Paste. — About 1 gram of the paste (accurately weighed) is mixed in a bottle filled with carbon dioxide, with 25 mils of air-free chloroform and 25 mils of air-free water, and the mixture shaken for fifteen ixrinutes. After separation the aqueous layer is siphoned off, and the chloroform shaken once more with 15 mils of air-free water to remove the last traces of oxidation products of the phosphorus. The water is again separated, the chloroform solution treated with copper nitrate solu- tion, and the estimation continued as above. Spirit of Phosphorus. — Twenty-five mils of spirit are mixed with 50 mils air-free chloroform and 50 mils water, the mixture well shaken, and when complete separation has taken place the chloroformic solution drawn into a flask filled with carbon dioxide. The aqueous solution is shaken with two more portions of 25 mils each of chloroform, the combined chloro- formic liquids treated with copper nitrate in the usual way and the esti- mation completed as above. Phosphorus Pills. — A quantity of pills equivalent to about one grain of phosphorus is mixed in a bottle with 25 mils of air-free water and 100 1 J. Am. Pharm. Assn., 1915, 4, 451. NON-METALS AND THEIR COMPOUNDS 959 mils of air-free chloroform. The air in the bottle is replaced by carbon dioxide and the mixture well shaken until the pills are disintegrated. After allowing the liquids to separate as much as possible the aqueous layer is siphoned off. The mixture is then shaken with sufficient tragacanth to eliminate the remaining water, an aliquot of the chloroformic solution filtered off, treated with copper nitrate, etc. Elixir of Phosphorus. — Twenty-five mils of the elixir are mixed with 50 mils air-free water in a separator, the air displaced by carbon dioxide, and the mixture shaken with 50, 25, and 25 mils air-free chloroform. The combined chloroformic liquids are shaken out once with 10 mils of air- free water to wash out any phosphorus oxidation products, separated and the chloroform solution treated with copper nitrate in the regular way. PHOSPHORUS COMPOUNDS The phosphorus compounds occurring in medicinal preparations con- sist of the salts of phosphoric, hypophosphorus and glycerophosphoric acids, phosphides and organic substances containing phosphorus in com- bination. Plant extracts contain phosphates and probably organic sub- stances containing phosphorus. The coatings and subcoatings of pills and tablets sometimes contain phosphates, so that the presence of phosphates does not necessarily indicate that it is there as a remedial agent. Of the phosphides, the zinc compound is the only one of importance, and it may occur in the same class of mixtures that elemental phosphorus does and the remedies are used for the same purpose. Sodium phosphate is an important drug. Calcium phosphate is used as a remedy and is an important constituent of dentifrices. It is also employed as a mechanical agent in molding pills and tablets. Iron phosphate and pyrophosphate are important and potassium phos- phate is used as an alterative. Magnesium phosphate is of lesser impor- tance, as are the lactophosphates of the alkalies and alkaline earths, which are probably mixtures of the salts of the two acids, lactic and phosphoric. The glycerophosphates have been treated under ethereal salts. The hypophosphites of the alkalies, certain of the alkaline earths, and iron and manganese are important medicinal agents and are to be found largely in reconstructive tonics. The phosphites are of no importance in this work. The most delicate reaction of the phosphates is the production of the canary-yellow precipitate, when a solution of the substance in the pres- ence of nitric acid is warmed with an excess of ammonium molybdate. Silver nitrate gives a yellow precipitate with soluble orthophosphates and white precipitate with pyrophosphates and metaphosphates. Magnesium sulphate gives a white precipitate with pyrophosphates, 960 INORGANIC SECTION soluble in excess of magnesium sulphate and not reprecipitated in the cold by ammonia. It does not precipitate metaphosphates in the pres- ence of ammonium chloride. Egg albumen is coagulated when shaken with metaphosphoric acid or with metaphosphates acidified with acetic acid. The ortho and meta acids are without action. Phosphites are strong reducing agents. With silver nitrate a precipi- tate is produced which is momentarily white but which soon blackens. Mercuric salts are reduced to mercurous, and then to metallic mercury. When strongly heated, phosphites decompose, giving off phosphoretted hydrogen. Hypophosphites are all soluble in water. They are even more power- ful in their reducing action than phosphites. On adding copper sulphate to an acidulated solution of a hypophosphite and gently warming, a yellow- ish-brown precipitate is formed which quickly changes to chocolate-brown. This reaction distinguishes the hypophosphites from phosphites. When gently heated, hypophosphites evolve phosphoretted hydrogen. The determination of the phosphoric acid radicle in soluble phosphates may be accomplished by the well-known method of precipitation with ammonium molybdate in presence of nitric acid and either titrating the precipitate or converting it to magnesium pyrophosphate. If organic substances are present, the precipitation with molybdate is not complete. When this situation arises the sample should be diluted, made strongly ammoniacal and precipitated with magnesia mixture. The precipitate is recovered and washed free from mother liquor, dissolved in dilute nitric acid, and subjected to the molybdate precipitation. In some cases it may be desirable first to boil the sample with concentrated nitric acid, then dilute, precipitate with magnesia mixture, and proceed as above. If the qualitative examination shows the presence of a pyrophosphate and it is desired to estimate the amount, the sample must be boiled with nitric acid before precipitating with molybdate. Mixtures containing pyrophosphates may contain organic matter, and after boiling with nitric acid, the solution should be treated with excess of ammonia, magnesia mixture added, and the well-washed precipitate dissolved in nitric acid and precipitated with molybdate. In some instances the addition of ammonia to a complex mixture will cause a precipitate to appear before the magnesia mixture is introduced. But the subsequent solution of the precipitate in acid and precipitation with molybdate will eliminate any foreign substances. Hypophosphites are readily determined by conversion to phosphates by oxidizing with nitric acid or permanganate. If by any chance soluble phosphates and hypophosphites occur together, the phosphate may be sep- NON-METALS AND THEIR COMPOUNDS 961 arated by throwing it out of ammoniacal solution with magnesia mixture. Hypophosphites may be estimated by titration with permanganate. A dilute solution of the salt, free from organic matter, is acidified with dilute sulphuric acid, a slight excess of the reagent added and heated to 80 to 90° C, any red color remaining is removed by titration with oxalic acid. A further quantity of permanganate is then added and the same procedure repeated until the titration with oxalic acid shows that oxida- tion is complete. The determination of phosphoric acid in glycerophosphates is accom- plished by boiling under a reflux a solution of the sample with sulphuric acid and potassium bichromate for two hours. At the end of this period the hot mixture is diluted with water, the excess of bichromate reduced with sodium sulphite, and after the addition of sodium acetate, the phos- phate precipitated with molybdate in presence of nitric acid. This pro- cedure may be modified by neutralizing with ammonia after reducing the bichromate and making a preliminary precipitation with magnesia mixture, as was recommended in the assay of complex mixtures containing phosphates. CARBON AND CARBONIC ACID Wood charcoal is often present in remedies for certain forms of dys- pepsia. It is dispensed alone with sugar and methyl salicylate, and in combination with mercurous iodide, with bismuth subnitrate, with mag- nesium oxide, with Nux Vomica, and often pepsin, Capsicum, and ginger are included in the formula. The identification of carbon is a simple matter, because it is the only black substance which will withstand the action of chlorin even at high temperature. When burned in the presence of air or oxygen, the only product of combustion is carbon dioxide. Wood charcoal may be determined with sufficient accuracy by dis- solving out the other components of the tablet or lozenge with water, boiling the residual insoluble material with strong hydrochloric acid or chlorin water, diluting and filtering onto a Gooch. In case the insoluble mixture contains resistant siliceous matter, the carbon may be estimated by ignition in the organic combustion apparatus and the resulting carbon dioxide collected and weighed in the potash bulb. Sodium bicarbonate is used in combination with a large number of different drugs, and in granular effervescent preparations and artificial mineral water salts. The normal carbonates are ingredients of many preparations, and the basic or subcarbonates of a few metals, notably 962 INORGANIC SECTION^ bismuth, are extensively employed. Lithium carbonate is used as a diuretic and antirheumatic. Carbon dioxide, when dissolved in water, forms carbonic acid, H2CO3. The acid is capable of dissolving the normal carbonates of the alkaline earths and magnesium forming acid carbonates or bicarbonates. All normal carbonates are insoluble in water, except those of the alkalies. The acid or bicarbonates are all soluble, but on boiling their solutions they are converted into normal salts, which (except in the case of the alkali carbonates) are precipitated. The normal carbonates of the alkalies are readily distinguished from the bicarbonates. A cold aqueous solution of the latter does not color phenolphthalein, but on warming, effervescence takes place, owing to the escape of carbon dioxide, and the solution acquires a deep-pink color. These two classes of salts may also be distinguished by the difference in their behavior toward certain metallic solutions. With magnesium sulphate or chloride, normal alkali carbonates give a white precipitate of a basic carbonate, 5MgS0 4 +5Na 2 C0 3 = MgO •4MgC03+5Na 2 S0 4 +C02 Sodium bicarbonate gives no precipitate with magnesium salts, the car- bon dioxide being in sufficient quantity to redissolve the magnesium car- bonate, forming magnesium bicarbonate. With mercuric chloride the normal carbonates give a reddish pre- cipitate of a basic oxide, while the bicarbonate gives no precipitate. When strongly heated the normal carbonates of the alkali metals (not ammonium) remain unchanged. Those of the alkaline earths and other metals are converted into oxides with evolution of carbon dioxide. The presence of a carbonate is determined by the evolution of carbon dioxide when the substance is treated with dilute hydrochloric acid, the gas being identified by its action on lime or barytes water. Sulphur dioxide which also produces a white precipitate with these reagents is distinguished by its characteristic odor, but if the two gases are liberated together both may be identified by passing the mixture first through a solution of potassium permanganate, which will absorb the sulphur dioxide, and then into lime water. If the passage of the gases through the per- manganate be continued for a few minutes the color of the solution is entirely destroyed, and the liquid may then be tested for sulphuric acid by barium chloride. The determination of the CO3 radicle is seldom a matter of moment except in the cases of the alkali salts. In most of the other cases, after establishing the identity of the salt, the analysis proceeds to a determi- nation of the metallic element, and from this datum the percentage of salt is calculated. A consideration of the procedures to be adopted when NON-METALS AND THEIR COMPOUNDS 963 working with ammonium carbonate and ferrous carbonate is discussed under the heading of these individual compounds. The purity of an alkaline carbonate is determined by dissolving a weighed amount of the same in water and titrating with standard acid. The following table gives size of sample and amount of acid required for neutralization if the assay is conducted according to the U. S. P. recom- mendations. Sample H 2 Acid Alkali Ammonium Car- Not more than bonate 2 grams 50 mils 50 mils N/1 H 2 S0 4 boiled 12.7 mils N/KOH, Indi- cator litmus. Lithium Car- bonate 0.5 gram 20 mils N/1 H 2 S0 4 Not more than 6.6 mils N/KOH. ln- . dicator methyl orange. Potassium Car- bonate dried Not less than 14.3 Indicator methyl at 130° 1 gram 50 mils mils N/1 H 2 S0 4 orange Sodium Carbon- ate 1 gramNa 2 C0 3 -H 2 10 mils Not less than 32.3 Methyl orange .855 gram Na 2 C0 5 mils N/1 H 2 S0 4 Magnesium Car- bonate recent- ly ignited and cooled 0.4 gram 25 mils N/1 H 2 S0 4 Not more than 5.8 mils N/1 KOH. Methyl orange. The total carbonate in a granular effervescent salt is determined by treating the sample with dilate sulphuric acid and aspirating the evolved CO2 into tared potash bulbs or tubes of soda lime. Tube E contains pumice moistened with sulphuric acid, tube D con- tains pumice impregnated with anhydrous copper sulphate (prepared by soaking in strong copper sulphate solution and drying at 200° C.) and serves the purpose of absorbing acid vapors, tube A is filled about four-fifths with soda lime the remaining portion a, furthest removed from the incom- ing gas, being filled with dry calcium chloride. F is a guard tube of soda lime, G is a tube containing sufficient concentrated sulphuric acid to cover the bend, S contains soda lime for removing CO2 from the air during aspiration. 964 INORGANIC SECTION The sample amounting to one to two grams is weighed into B, the stopper covering the funnel with 25-50 mils dilute sulphuric acid is inserted, and the apparatus connected, the absorption tubes A and F having been previously weighed. The acid is allowed to enter the flask slowly, the rate regulated by the escape of bubbles through tube G, which should not be faster than two per second. When effervescence is at an end the remain- der of the acid is admitted, the stopcock left open, tube S attached and a slow stream of air aspirated through the system, gentle heat being applied to B. The aspiration should be continued for twenty to thirty minutes. When the process is completed, the aspiration is stopped, the absorption tubes disconnected, the ends stoppered, cooled, and weighed. The same apparatus and procedure can be used for determining the carbonates of the heavier metals used for excipients, etc., in other classes of medicinal preparations. Hydrochloric acid should be substituted for sulphuric. SILICON AND SILICATES Insoluble silicates find their way into medicinal products chiefly as excipients. Their exact determination is seldom a matter of moment unless one is concerned with working out a formula to its ultimate compo- NON-METALS AND THEIR COMPOUNDS 965 sition. In working with pills, tablets, and tooth powders it is usually sufficient to boil out everything that will dissolve in aqua regia, and then ignite the insoluble portion, and weigh the residue as siliceous matter. A complete analysis of an insoluble silicate is conducted as follows : From 1.5 to 3 grams of the silicate (which has been reduced to the finest possible powder, and dried) are weighed out into a platinum crucible of fairly large dimensions, and intimately mixed with five or six times its weight of fusion mixture, *(10Na2CO3 -I3K2CO3) by means of a stout platinum wire, or a thin glass rod with carefully rounded ends. The entire mixture should not more than hah fill the crucible. The covered crucible is then heated over a Bunsen flame, at first gently in order to expel the moisture present in the mixture, and afterward more strongly until the mass begins to melt round the edges. It is then heated by means of a blowpipe, until the decomposition is complete and the contents of the crucible are in a state of quiet fusion. Care must be taken, by regulating the heat of the blowpipe, to prevent undue frothing of the mass while the carbon dioxide is being evolved; the progress of the operation should be watched by momentarily slightly raising the crucible lid from time to time. When the operation is complete, the crucible is allowed to cool down, and when cold it is placed upon its side in a beaker with about 100 mils of water, care being taken that no impurities are conveyed into the solu- tion upon the outside of the crucible. The beaker is heated upon an iron plate or sand-bath, and the water allowed to boil gently until the " melt " is either entirely detached from the crucible or has become honeycombed by the action of the hot water. Hydrochloric acid is then cautiously added in small portions at a time (the clock-glass cover being partially withdrawn for each addition) until effervescence ceases, and no further precipitaion of gelatinous silicic acid takes place. The crucible and fid are then withdrawn and rinsed into the beaker. The mixture is transferred to a dish, and evaporated to dryness upon a steam-bath, the gelatinous mass, as it stiffens, being stirred at frequent intervals with a short glass rod, in order to break it up as much as possible and thus expedite the drying. When the mass has become white and pulverulent, the dish is transferred to an air-bath, and heated to about 160° for hah an hour. The residue is then moistened with a little strong hydrochloric acid, and digested upon the steam-bath for a short time, acid being added as evaporation goes on. Hot water is added, and the silica washed several times by decantation with hot water, after which it is transferred to the filter and washed until the wash-water is free from chlorides. The silica is dried in the steam-oven, transferred to a platinum cru- cible, and the paper incinerated upon a platinum spiral. The covered 966 INORGANIC SECTION crucible is heated, at first very cautiously with a small flame, and after- ward to a red heat, and weighed until constant. Aluminum silicate forms the base of a class of soothing antiphlogistine preparations popular as applications for wounds, and swellings and as substitutes for poultices. These products are usually sold under fanciful names suggestive of their antiphlogistic properties and consist of the base with glycerin, boric acid, menthol, thymol, eucalyptol and ammonium iodide. Cataplasm of kaolin of the U. S. P. is a type of this class of prod- ucts and contains 57,7 per cent kaolin, BORON AND BORATES Boric acid and sodium tetraborate are important medicinal agents. The latter is found in antiseptic dusting powders, gauzes, and washes; in soothing emollient preparations with glycerin, extract of witch hazel and Irish moss, as an excipient or lubricant in pills and tablets, and as an active ingredient of certain formulas used in cystitis, leucorrhea, and for gargles. It is found in eye washes, in liquids of the listerine type, and in ointments and salves combined with menthol, thymol, camphor, etc. Sodium tetraborate or borax is a constituent of many alkaline anti- septic tablets, washes, and gargles; it is combined with potassium chlorate, cocain hydrochloride, resorcin, etc., and will be found in cystitis mixtures. It has been used as a remedy for epilepsy. Sodium perborate, NaB03+4H20, is an antiseptic, deodorant, and bactericide, and liberates active oxygen when treated with dilute acids or water. It is used in the treatment of wounds, sores, ulcers, and dis- agreeable discharges, and is a component of certain classes of dentifrices, and so-called " peroxide " cold creams. Zinc borate and perborate are used in dusting powders for wounds and eczema, as are also calcium borate and magnesium borate, the latter known as " Antifugin." Boric acid is an ingredient of the antiphlogistic pastes popularly sold as applications for wounds and bruises following the formula of cataplasm of kaolin of the U. S. P. Determination of Boric Acid. — Boric Acid alone and in Talcum Powders Free from Carbonates. — The sample is treated with water, an equal volume of glycerin added and titrated with sodium hydroxide using phenol- phthalein. In the U. S. P. assay for boric acid, if 1 gram is dissolved in 50 mils of water, 50 mils of glycerin added, not less than 16.2 mils N/l sodium hydroxide should be required for neutralization. Boric Acid or Borates in Presence of Carbonates. — The sample is treated with standard acid until the solution reacts acid to methyl orange. It NON-METALS AND THEIR COMPOUNDS 967 is then boiled under a reflux until carbon dioxide is expelled, cooled, neu- tralized to methyl orange, an equal volume of neutral glycerin added, and titrated with standard alkali using phenolphthalein. Borates insoluble in water are dissolved in dilute hydrochloric acid in the cold or under a reflux, and treated as above. Boric Acid and Borates in the Presence of Aluminum and Iron. — The sample is dissolved in hydrochloric acid and heated under a reflux until carbon dioxide is expelled. The mixture is cooled and made up to volume, an aliquot filtered off, nearly neutralized to methyl orange, barium carbonate added, warmed on steam-bath for half an hour, cooled, filtered, the filtrate treated with an equal volume of glycerin, and titrated as above. Boric Acid and Borates in Salves and Ointments. — Five grams of the sample are treated with 30 mils of neutral glycerin and 50 mils of water and warmed on the steam-bath until the ointment is melted. The aqueous liquid is then treated as usual. Another procedure is to dissolve the fats and oils in petroleum ether and wash the mixture with water. After separating, the ethereal layer is washed again with water and the combined aqueous solutions titrated. Separation of Boric Acid from Other Substances, as Methyl Borate. — The following procedure is described by M. F. Schaak: 1 The apparatus for distillation may conveniently be arranged as follows: A long wide-necked 200-mil Kjeldahl flask may serve as the decomposing flask. This flask is fitted with a stopper carrying three tubes, one of which serves to connect it with a condenser in such a manner as to avoid any of the acid liquid being carried over during the distillation. Another tube is to be connected with a flask for supplying a current of methyl alcohol vapor which is to be conducted to the bottom of the decomposing flask, thus serving to keep the mixture agitated and avoid bumping during the distillation. The third tube serves to introduce the methyl alcohol needed to form the mixture with the sulphuric acid and the substance, and may also be fitted with a clamp and valve for equalizing the pressure when needed. The receiver which is a tube connected with the condenser is trapped with a Mohr's bulb. For the estimation a portion of the dry, finely pulverized substance is placed into a long, narrow tube and weighed. The contents are then emptied into the decomposing flask, without allowing any of the sub- stance to remain in the neck of the flask. The tube is now weighed again, the difference being the amount of substance used for the estimation. A sufficient amount of concentrated sulphuric acid is added to form a thin paste with the substance, and the flask heated gently to expel carbon dioxide or other volatile acid, and cooled. About 60 mils of water are placed in the receiver, the terminal tube 1 J. Soc. Chem. IncL 1904, 23, 700. 968 INORGANIC SECTION of the condenser being made to dip into the water. The Mohr's bulb is also filled with water and attached as a trap to the receiver. The decom- posing flask, containing the cold mixture of the substance and sulphuric acid, is now connected with the flask for the generation of methyl alcohol vapor, and with the condenser, all the connections being air-tight. The distillation is then started by adding to the decomposing flask, in one portion, sufficient cold methyl alcohol to equal about 20 times the amount of free sulphuric acid present. Methyl alcohol vapors are then passed from the generating flask until the boric acid has all passed into the receiver. During the distillation the decomposing flask is heated to a temper- ature sufficient to prevent any marked change of volume of the methyl alcohol which was originally added. The distillation will usually be complete in about thirty minutes, when the receiver can be changed, and, to ensure complete removal of the boric acid from the substance, a further distillate collected and tested. The water from the Mohr's bulb is added to the distillate, which is then neutralized with alkali, when necessary, by the aid of Congo-red or methyl orange test-paper. The titration is then completed after the addition of neutral glycerol and phenolphthalein. When pure methyl alcohol is used and care is taken not to allow the mixture with sulphuric acid in the decomposing flask to become concen- trated, accurate results can be attained, even in the presence of large amounts of chlorides and carbonates. Fluorine, when present in large amount, must be removed from the substance before distillation. PERBORATES The perborates have assumed considerable prominence during recent years because of the ease and rapidity by which hydrogen peroxide is evolved when they are treated with water or dilute acids. Certain salts of other acids containing a large amount of oxygen have been placed on the market and the analyst will be confronted with the problem of decid- ing which particular substance has been used in compounding a mixture. Lenz and Richter : have studied the reactions of a number of these sub- stances toward certain reagents. They compare the behavior of (a) sodium perborate, (b) potassium percarbonate, (c) ammonium persulphate, (d) potassium perchlorate, and (e) periodic acid; a and b are decomposed by water with the formation of hydrogen peroxide and liberation of oxygen; c gives oxygen only. Permanganate solution in the presence of sulphuric acid is decolorized by a and b and by c slightly on heating; d and e have no effect; alkaline permanganate is turned blue by d. With 1 Znal. Chem., 1911, 50, 537. NON-METALS AND THEIR COMPOUNDS 969 silver nitrate solution a heavy black precipitate is produced by a (a mirror on warming in the presence of ammonia) ; a white precipitate turning gray on warming, with b; a solution of c becomes turbid through the separation of blue molecular silver; d has no action; e gives a pale-yellow precipitate readily soluble in ammonia, a, b, c, and e cause the darkening of freshly precipitated manganous hydroxide (in absence of air); d has no effect. The precipitate obtained by adding sodium hydroxide to cobalt nitrate, in absence of air (under petroleum ether) is darkened at once by a, b, and c, but not by d and e. When nickel sulphate is treated similarly, a black precipitate is given by c; the others have no effect. Alkaline lead acetate solution, when heated with an excess of c, gives a yellow-red precipitate after a time; with e a heavy white crystalline precipitate is obtained; a, b, and d have no effect. Cerous chloride solution, in the presence of ammonia, is colored yellow by a and b; the others have no effect. Iodin is liberated from potassium iodide by c, and in the presence of sulphuric acid by a and b; d has no effect. Fuchsin solution, containing sodium acetate, is decolorized by a, b, and c on warming, but not by d. Anilin sulphate solution is colored a pale yellow when heated with a or b ; c gives a dark-brown precipitate and d has no action. E. K. Farrar l has proposed the following method for the estimation of perborates. A known weight of the sample in the solid condition is added to an excess of ferrous ammonium sulphate in water which has been acidulated with sulphuric acid. Potassium thiocyanate is added as an indicator, and the ferric iron titrated with a standard solution of titanous chloride. An alternative method consists in adding the sample to a measured volume of titanous chloride solution which must be in excess (the operation being performed in an atmosphere of CO2) and titrating the excess of titanous chloride with iron alum, using potassium thiocyanate as indicator. Estimation of Perborates in Soap Mixtures, Creams, etc. — The sample is weighed into a glass-stoppered volumetric flask, water added, warmed to 50 to 60° and shaken for five minutes. Dilute sulphuric acid is added in excess, followed by 1 gram ignited kieselguhr, the solution made up to volume and allowed to settle. Aliquot s are then filtered off and titrated with permanganate. 1 J. Soc. Dyers and Col., 1910, 26, 81. CHAPTER XXVI METALS AND THEIR COMPOUNDS SILVER Silver compounds are important therapeutic agents. They function- ate as antiseptics and bactericides, and in some forms are introduced directly into the blood stream. Silver salts are also employed as alter- atives, stimulants, and nerve sedatives, and preparations containing them will be found recommended for a wide range of ailments, including epilepsy, locomotor ataxia, typhoid fever, chronic diarrhea, gastric troubles, etc. They find their widest use in gynecological practice, and on account of the demand for non-irritant agents, there have sprung up a quantity of organic silver compounds of indefinite composition. Of late silver salts have been exploited as cures for the tobacco habit. The salts used as medicaments include the nitrate, acetate, arsenite, chloride, citrate, cyanide, iodate, iodide, lactate, and sulphocarbolate. The oxide, mixed with chalk, is dispensed in capsules. The organic com- binations are chiefly of a proteid nature, and will be discussed individually. Silver nitrate is recognized in the U. S. P. Molded silver nitrate or lunar caustic is the crystalline salt with 4' per cent hydrochloric acid. Mitigated silver nitrate U. S. P. contains 33J per cent of the crystalline salt, with the balance potassium nitrate. It is sometimes called mitigated lunar caustic No. 4. Two other mixtures of these two salts are marketed, one containing 67 per cent and the other 50 per cent AgN03, and known respectively as mitigated lunar caustic No. 2 and No. 3. These remedies are used in the treatment of the diseases above mentioned, and are locally applied hi gonorrhea, conjunctivitis, cystitis, stricture, excrescences, warts, ulcers, hemorrhoids, chancre, diphtheria, hydrocele, smallpox, etc. Silver cyanide and oxide are both recognized in the U. S. P. Silver in inorganic combinations is readily recognized when conducting the regular scheme of qualitative analysis, but when in organic combinations and under certain conditions in the presence of organic acids, it does not respond to the analytical reagents. When the latter condition prevails the organic matter must be destroyed by digestion with nitric and sulphuric acid before the identification tests can be applied. For assaying silver nitrate crystals, molded silver nitrate and mitigated 970 METALS AND THEIR COMPOUNDS 971 silver nitrate, the pharmacopoeial procedure consists in dissolving the salt in 10 mils of water, adding a certain quantity of sodium chloride standard solution and then titrating back with a certain limited amount of silver nitrate. Amt. used N/10 NaCl N/lOAgNOa Indicator Silver Nitrate. . Molded silver nitrate .... Mitigated silver nitrate. . 0.5 gram 0.5 gram 1 . gram 30 mils 30 mils 20mi]s 0.4 mil 1.9 mils 0.3 mil 3 drops K 2 Cr0 4 3 drops K 2 Cr0 4 3 drops K 2 Cr0 4 In assaying silver cyanide, the salt is fused in a porcelain crucible, and after ignition, should leave a residue of metallic silver amounting to 80.48 per cent of its original weight. No better method for estimating silver exists than precipitating a solution of the salt with dilute hydrochloric acid in presence of nitric acid, and weighing the silver chloride on a Gooch. If the sample in hand consists entirely of inorganic material, and the silver salt is soluble in water, and there are no other metals present pre- cipitated by hydrochloric acid, a weighed amount is diluted with water to about 100 to 200 mils, filtered if necessary from any insoluble residue, 5 to 10 mils dilute nitric acid added, heated to boiling, and dilute hydro- chloric added until the precipitate coagulates and settles out, leaving the supernatant liquid clear when the flame is withdrawn. If the addition of a few drops of hydrochloric acid shows that the precipitation is complete, the silver chloride is collected on a tared Gooch, washed with water, rinsed with alcohol and ether, and dried at 100°. AgCl : Ag=l : 0-75202 If the sample contains a halogen salt of silver, the metal may be obtained in a solution by fusing in a porcelain crucible, adding water, followed by a piece of pure zinc and some dilute sulphuric acid. The reduced spongy silver is afterward washed with dilute sulphuric acid and water, and then dissolved in nitric acid. If the sample consists of a colloidal suspension of silver oxide or an organic mixture, a weighed quantity is either evaporated or treated with 10 to 15 mils concentrated sulphuric acid in a porcelain evaporating dish, and heated until well charred. After cooling, nitric acid is added, heated, and if the liquid does not char again after the nitrous fumes have all boiled away, it is cooled, diluted with water, and precipitated with hydrochloric acid, as above. Should lead or mercuric mercury be present simultane- ously with silver a small quantity of sodium acetate should be added to insure the complete precipitation of the silver chloride. 972 INORGANIC SECTION In some cases it will be sufficient to ignite the substance in a porcelain crucible and weigh the resulting silver. Igniting should be gentle at first afterward with the full flame. If the substance leaves a residue which appears to contain silver chloride or a halogen salt, it is converted to me- tallic silver with zinc and sulphuric acid, and the determination completed by dissolving in nitric acid and precipitating with hydrochloric acid. COLLOIDAL SILVER Under certain conditions silver in a very fine state of subdivision forms a colloidal suspension which gives with water a mixture closely resembling a solution. Colloidal silver is not precipitated by the ordinary reagents which precipitate the metal from solution, thus sodium chloride or albu- men are without effect, but if the suspension is first warmed with nitric acid until the silver is dissolved, the resulting solution will respond to the usual silver tests. Colloidal silver is used for the preparation of ointments, dusting powders, vaginal tampons, suppositories, and tablets. Among the colloidal preparations on the market may be mentioned, Cargentos, Collargol, and Electrargol. Cargentos is said to be prepared by precipitating an alkaline solution of silver casemate and silver oxide with an acid, chssolving the precipitate in an alkali, dialyzing the resulting solution against running water and evaporating the remaining colloidal suspension to dryness in vacuo. It occurs in odorless and tasteless black scales of metallic luster, which fonxi colloidal suspensions with water and glycerin. It contains from 48 to 52 per cent metallic silver. Collargol occurs in hard, brittle, bluish-black, scale-like pieces, forming with water a dark olive-brown colloidal suspension. Electrargol is a colloidal suspension of silver containing a small per- centage of sodium arabate. It contains silver equivalent to .25 per cent. It is prepared by passing an electric current in the form of an arc between two silver electrodes in distilled water. It is made stable by the addition of sodium arabate. The liquid is odorless and tasteless, appearing trans- parent by transmitted light and opaque and gray by reflected light. SILVER COMPOUNDS WITH PROTEIN SUBSTANCES Albargin. — Gelatosesilver Albargin is a compound of silver nitrate with gelatose, containing from 13 to 15 per cent of silver. It is prepared by adding silver nitrate to a solution of gelatose in water, evaporating the solution or precipitating the compound by the addition of ether or alcohol. It is a coarse, yellow, shining powder, very easily METALS AND THEIR COMPOUNDS 973 soluble in water, forming neutral solutions. The presence of gelatose, silver, and a nitrate can be shown by appropriate tests. It is incompatible with tannin and chlorides. Argonin. — Caseinsilver — Silvercasein Argonin is a compound of silver and casein containing 4.28 per cent of silver. It is prepared by precipitating an alkaline solution of casein with silver nitrate and alcohol. It is a fine, nearly white powder, easily soluble in water, forming an opalescent, faintly alkaline solution, which becomes clear on the addition of sodium chloride. It is also soluble in alkaline solutions, in egg albumen, blood serum, etc. The usual reagents for silver do not affect its aqueous solution (1 in 20), which should remain clear on addition of sodium chloride, and should not be affected by hydrogen sulphide. On incineration argonin should yield at least 4 per cent of silver, which may be identified by the usual tests after solution in dilute nitric acid, It is incompatible with acids. Argyrol. — Silver Vitellin Argyrol is a compound of a derived proteid and silver oxide, containing from 20 to 25 per cent of silver. The so-called vitellin is said to be prepared by electrolytic decompo- sition of serum albumin. To this product, finely suspended in water, is added freshly precipitated, moist silver oxide and the mixture is heated under pressure until combination occurs. The liquid is then evaporated to dryness in vacuo. The change in the proteid is in question; probably a compound of hydrolyzed proteid (serum albumin) and silver oxide is formed. Argyrol occurs in black, ghstening, hygroscopic scales. The solution is yellowish or black, depending on concentration, and is not affected by boiling. Solutions of argyrol stain the skin. It gives a slight cloudiness or precipitate with sodium chloride and hydrochloric acid; on addition of ferric chloride the color is discharged with formation of a white cloud. With alkali and copper sulphate it gives a slight biuret reaction. It has a slight metallic taste. Silver is recognized in the usual way. The compound is said to be incompatible with acids and most of the neutral and acid salts in strong solution. Hegonon. — Silver Nitrate Ammonia Albumose Hegonon is a substance obtained by treating silver ammonium nitrate with albumose, said to contain approximately 7 per cent of organically combined silver. 974 INORGANIC SECTION It is a light-brown powder readily soluble in water. Its aqueous solu- tions do not coagulate albumin, even on heating, nor are they precipitated by sodium chloride. Novargan. — Silver Proteinate Novargan is an organic silver-albumin compound containing 10 per cent of silver. It is a fine yellow powder, soluble in water, forming a practically neutral solution, from which it is not precipitated by sodium chloride, nor affected by the usual reagents for silver salts. The solution is darkened by hydrogen sulphide or ammonium sulphide, but no precipitate is produced. Protargol. — Protein Silver Salt Protargol is a compound of albumin and silver, containing 8.3 per cent of silver in organic combination. According to the patent specifications insoluble protein silver com- pounds, obtained by treating protein bodies with silver salt, are rendered soluble by treatment with a solution of albumoses. It is a light-brown powder, soluble in twice its weight of cold water, producing a solution which is not affected by the ordinary precipitants of silver salts, such as alkalies, sulphides, chlorides, bromides, iodides, nor by heat. Ammonium sulphide gives a dark color to the solution without pre- cipitation. Addition of strong hydrochloric acid produces a precipitate of unchanged protargol, soluble in a large quantity of water. A solution containing sulphuric acid is not colored blue by diphenylamine. It is compatible with picric acid and picrates and with most metallic salts. Sophol Sophol is a compound of silver and methylene-nucleinic acid, contain- ing about 20 per cent metallic silver. It is prepared by corrosion of insolu- ble silver compounds of methylene-nucleinic acid into soluble silver com- pounds by treatment with neutral salts, such as sodium chloride. It is a yellowish powder, readily soluble in water, insoluble in alcohol or ether. The aqueous solution has a faint alkaline reaction and is not precipitated by dilute sodium hydroxide or by sodium chloride. When boiled with dilute alkali it assumes a black color and the odor of formaldehyde is appa- rent. An aqueous solution yields a yellowish precipitate on warming with nitric acid ; the precipitate is soluble in ammonia, the solution becom- ing orange. METALS AND THEIR COMPOUNDS 975 Nargol Nargol is a compound of silver and nucleinic acid and contains about 10 per cent of metallic silver. Largin Largin is a protein compound of silver containing 11 per cent of the metal. It is a gray powder, soluble in water and glycerin. Argentamin. — Ethylene-Diamine-Silver Nitrate Argentamin is an aqueous solution of silver nitrate and ethylene- diamine, corresponding to 10 per cent of silver nitrate. It is prepared by dissolving 10 parts each of silver nitrate and ethylene- diamine in 100 parts of water. It is a colorless, alkaline liquid, turning yellow on exposure to the light, but not precipitable by chlorides or albumin. LEAD Lead acetate is astringent and sedative and will be found in pills and tablets combined with opium and camphor, and in astringent washes with Hydrastis alkaloids, zinc salts, and morphin. It is a component of liquid hair dyes when it occurs with suspended sulphur. Its solution is also used as an astringent eye lotion and as an injection and wash for gonorrhea. The subacetate is employed in solution, the 25 per cent strength being known as Goulard's extract and the 1 per cent solution being official. It is employed externally for burns, bruises, sprains, blisters, inflamed con- ditions of the eyes, ivy poison, erysipelas, and as an injection for gonorrhea. Lead sub-carbonate, 2PbC03-Pb(OH)2, is used as a dusting powder for burns, and occurs in ointments for ulcers, carbuncles, and skin diseases. It will be found in cosmetics, powders and creams. Lead nitrate is employed in a limited way for the same purposes as the acetate. Lead monoxid, PbO, the yellow oxide or litharge, is one of the forms in which lead is exhibited in ointments. The sulphite is used as a local application for erysipelas, scabies, and various skin affections. The tannate is used for the same purposes. Lead oleate is the lead compound present in lead plasters. It is soluble in alcohol, ether, and oil of turpentine. This compound is the basis of certain types of proprietary ointments recommended for raw sores and infections, bites of animals, wounds, etc., where it is combined with Peru or Tolu balsams. Lead sulphocarbolate is a crystalline salt soluble in water and alcohol. The diiodophenolsulphonate is known as Sozoiodole-lead, and is slightly soluble in cold water, and dissolves readily in presence of acetic acid. 976 INORGANIC SECTION The identification of lead when present in inorganic combinations and in most of the organic compounds, will result when the regular scheme of analysis is followed. If one is working with a plaster or a stiff ointment, lead oleate will dissolve in ether, and on shaking with dilute sulphuric acid, insoluble lead sulphate is formed, which can be filtered out from the acid solution and identified by appropriate means. Lead is determined by conversion to the sulphate or sulphide. It the sample contains lead acetate or nitrate in solution in water, or capable of solution in water free from organic matter a weighed amoimt is filtered from any insoluble matter, and treated with an excess of moderately dilute sulphuric acid and double the volume of ethyl alcohol. After standing a few hours, the precipitate is collected on a tared ignited Gooch, washed with water, and alcohol, dried and ignited. If the solution contains nitric acid or a nitrate, it is advisable to evaporate on the steam-bath after the addition of the sulphuric acid until all of the nitric acid is expelled. The residue is then diluted, alcohol added and the remainder of the determi- nation conducted as above described. If the sample is a powder and contains lead carbonate or oxide, the lead is brought into solution by treatment with nitric acid. Should calcium salts be present simultaneously with lead, the precipitation with sulphuric acid cannot be followed, and resort must be had to the sulphide determi- nation. Ointments containing inorganic lead salts are first treated with ether to dissolve the fatty base, and the insoluble lead salts brought into solu- tion with nitric acid. Lead plasters or ointments containing lead oleate may be dissolved in ether, transferred to a separatory funnel, and shaken with dilute sulphuric acid. The acid layer containing the lead sulphate is conducted into a flask, and the ethereal layer repeatedly shaken, if necessary, with the acid until no further precipitate takes place. The combined acid mixtures are then treated with twice the volume of alcohol and the remainder of the determination conducted as above. If the plaster or ointment contains no other inorganic salt, the follow- ing procedure may be used : Determination of Lead in Mixed Galenicals. — If it is desired to deter- mine the lead in the whole plaster including the gauze, weigh out a sample of about 5 to 10 grams and place it in a tared porcelain evaporating dish of about 100 mils. If it is desired to determine the lead as the medicament alone, the plaster must be weighed then treatea with ether in a porcelain dish large enough to hold the plaster spread cut and the ethereal extract should be carefully transferred to the tared evaporating dish in which the sub- sequent digestion is to be made, and the solvent evaporated on the steam- METALS AND THEIR COMPOUNDS 977 bath. After three or four washings and gauze will be free from the lead salt and may be dried and weighed, the difference in the weighing represent- ing the medicament. Cover the material in the evaporating dish with 100 mils of concen- trated sulphuric acid and heat over the steam-bath. Watch carefully and remove from the bath if there is violent frothing. When the mixture is thoroughly charred transfer to an asbestos plate and heat gently for an hour or more until SO3 fumes cease to be evolved. Cool. Add 5 mils fuming nitric acid and allow to digest until violent reaction is over. Add 5 mils concentrated sulphuric acid and heat gently as before and remove flame if reaction becomes violent. After the last fumes of SO3 have been driven off, place the evaporating dish over the free flame and heat at a low heat so that carbonaceous matter will ignite slowly. If there still remains any quantity of resistant carbonaceous material, allow the dish to cool, add 5 mils fuming nitric acid and allow to digest overnight. Evaporate off excess of acid on steam-bath, add 5 mils con- centrated sulphuric acid. Heat gently over asbestos plate as before and finally ignite at low redness. This last treatment with nitric acid and sulphuric acid will generally yield a white residue. Cool and weigh as lead sulphate. Note. — To obtain an even heat and prevent spurting when evapo- rated over asbestos plate, place a pipestem triangle on the asbestos and the evaporating dish on this. When soluble lead salts occur in pills or tablets with organic matter which will yield a precipitate with lead, the sample should be well ground, triturated with water, and the aqueous liquid filtered. The residue is then triturated with 5 per cent potassium hydroxide which is poured into the filter, the alkaline liquor collected, and added to the aqueous solution. The solution is then subjected to a stream of hydrogen sulphide, and when precipitation is complete, the sulphide is collected on a tared Gooch, well washed with hot water, dried with alcohol, washed with freshly distilled carbon bisulphide, again washed with alcohol, dried at 100° and weighed. If zinc or iron are known to be present, the combined sulphides are filtered, washed, and then treated with dilute hydrochloric acid before addition of alcohol and carbon bisulphide. Assay of Goulard's Extract U. S. P. — Transfer about 1.5 gram, accu- rately weighed, to a 200-mil measuring flask, dilute with 50 mils recently boiled distilled water, then add 50 mils N/10 oxalic acid, agitate the mix- ture thoroughly for five minutes, fill to the mark with distilled water, and filter rejecting the first 20 mils of the filtrate. Add 5 mils of sulphuric acid to 100 mils of the filtrate (representing one-half the amount of solu- tion originally taken), warm to about 70° and titrate with N/10 permanga- 978 INORGANIC SECTION nate. It shows not less than 18 per cent of lead.- Each mil of N/10 oxalic used corresponds to .010355 gram of lead. MERCURY Mercury, its salts and organic compounds are important remedial agents. Metallic mercury in confection of rose is known as Blue Mass, and is used as a cathartic and alterative. Mercury with chalk is used as an anti- emetic and alterative, especially adapted for children. Blue mass is dis- pensed in pills and tablets by itself and in combination with ipecac and opium ; with colocynth compound alone and combined with ipecac, Hyos- cyamus, aloes, or rhubarb; with colocynth compound, ipecac, strychnin, and belladonna; with Podophyllum resin; with Nux Vomica, Hyoscyamus, Capsicum and Podophyllum resin; with aloes, jalap, and tartar emetic; with ipecac and Gelsemium; with quinin and black pepper oleoresin; with rhubarb and sodium bicarbonate ; with aloes and Podophyllum resin ; with Digitalis and squills; with aloes, scammony, croton oil, myrrh, and oil of caraway; with strychnin, ipecac, Capsicum, and gentian; with quinin, Colchicum, Hyoscyamus, and opium. Mercury and chalk is dispensed alone in pills and tablet triturates. It is combined with gentian, ipecac, and opium; with gentian, Nux Vomica and reduced iron; with salol and bismuth subnitrate; with opium, camphor, bismuth subnitrate, kino and sodium bicarbonate. Mercurial ointment consists of mercury in a fine state of subdivision, in a medium of suet and lard. Oleate of mercury is added in small amount in the preparation of the U. S. P. product. This preparation is used exten- sively to destroy parasitic infections, as a resolvent in glandular swellings, venereal disease, for smallpox, erysipelas, and chilblains. Compound mercurial ointment contains in addition to the regular formula, camphor, olive oil, and beeswax. Oxides of Mercury Red mercuric oxide or red precipitate, is used externally for chancres, ulcers, ringworm, and inflamed conditions of the eyes. The yellow oxide is employed in syphilis and in acute and chronic derangements of the alimentary tract, in typhoid fever, phthisis, and functional disturbance of the liver. These substances are administered chiefly in the form of ointments. Black oxide of mercury is oxydimercurous ammonium nitrate, Hg20+NH 2 Hg 2 N03, and should not be confused with the true oxides of mercury. METALS AND THEIR COMPOUNDS 979 Mercuric Salts Mercuric chloride is employed as an antiseptic and germicide, both in professional and household practice. It is also used in syphilis, and externally as a stimulant and escharotic. Mercuric chloride pills and tablets are prepared in several different strengths from 1/1000 to 1/8 grain. Antiseptic tablets are composed of mercuric chloride with either ammonium chloride, sodium chloride, or citric acid, often colored red or blue. Antisyphilitic pills contain mercuric chloride and potassium iodide, sometimes with the addition of opium. Mercuric chloride is also com- bined with morphin and copper arsenite ; with quinin, ferric chloride, and arsenic chloride; with potassium iodide, ferrous iodide, arsenic iodide, and Nux Vomica; with opium and guaiac. Mercuric chloride is used in the preparation of antiseptic bandages and surgical dressings. Mercuric bromide is combined with the bromides of gold and arsenic in remedies for neurasthenic and anemic conditions. Mercuric iodide, red iodide, is used in syphilis, rheumatic conditions due to venereal disorders and scrofula, and externally for lupus. Mer- curic iodide is dispensed in pills and tablets alone and in combination with arsenic and ferrous iodides; with aconite, belladonna, and bryonia for tonsillitis; with morphin, sodium salicylate, and methyl salicylate. It is also used in the preparation of surgical soaps. Mercuric cyanide is recommended in diphtheria, membranous croup, and syphilis. It is used in the form of a gargle and tampons. Mercuric nitrate is used internally for syphilis and scrofula, and exter- nally for removing freckles and absorbing boils. Mercuric acetate, arsenate, benzoate, cacodylate, gallate, iodate, oxy- cyanide, phosphate, basic salicylate, carbolate, basic sulphate, are all used medicinally in limited amount. Mercurous Salts Mercurous chloride or calomel combines the general properties of mer- curial salts with those of a purgative and anthelmintic. Calomel is pre- pared for administration in pills and tablets of different strengths. It is combined with sodium carbonate ; with ipecac ; with ipecac and opium ; with Podophyllum resin and sodium bicarbonate; with bismuth sub- nitrate; with Capsicum; with santonin; with ipecac and bismuth sub- nitrate; with sulphurated antimony and guaiac, and castor oil (Antimony comp. U. S. P. Plummer pills); with colocynth compound; with opium; with rhubarb, colocynth compound, and Hyoscyamus; with colocynth compound, jalap, gamboge, Hyoscyamus, and oil of peppermint; with colocynth compound, jalap, ginger, gamboge, and rhubarb; with colocynth 980 INORGANIC SECTION compound, jalap, and gamboge (Cathartic Comp. U. S. P.); with aloes, rhubarb, and soap; with morphin, Capsicum, ipecac, and camphor; with Podophyllum resin, colocynth compound, belladonna, ipecac, Nux Vomica, and oil of anise; with aloes, jalap, gamboge, Veronica officinalis, Capsicum, Veratrum viride, and croton oil; with colocynth compound, Nux Vomica, aloes, Hyoscyamus, and ipecac; with colocynth compound, Colchicum, and Hyoscyamus; with Euonymus, ipecac, Podophyllum resin, and aloin; with zinc sulphocarbolate, salol, bismuth subnitrate and pancreatin; with atropin, morphin, and aconite; with quinin, ipecac, opium, aconite, aloin, and Capsicum. Mercurous iodide (yellow iodide) is an antisyphilitic. It is dispensed in pills and tablets alone and in combination with opium; with charcoal; with Conium, Lactucarium, and opium; with Podophyllum resin, aloin, Hyoscyamus, and Nux Vomica. Mercurous bromide is used as an alterative and antiseptic. Ammoniated mercury, HgNH2Cl, or white precipitate, is obtained by precipitating mercuric chloride with excess of ammonia. This salt is used externally in skin diseases, syphilitic sores and eruptions, and is often found in cosmetics. The term " white precipitate " (precipite blanc) is confusing, as it is used by the French as a term for designating calomel. Mercury oleate, prepared from mercuric oxide and oleic acid, is one of the forms in which mercury is administered internally. Mercuric succinimide is a salt of mercury and succinic acidimide. When suspended in ether and subjected to a stream of hydrogen sulphide, the mercury is precipitated as sulphide and the succinimide can be sub- sequently recovered from the ether. Afridol Afridol is sodium hydroxymercuric toluylate, C6H 3 (CH3)(COONa)HgOH 2:3:1. It is an odorless, tasteless white powder, difficultly soluble in neutral or acid media, but soluble in ammoniacal solution contain- ing ammonium chloride. Filtered aqueous solutions of afridol remain unchanged on the addition of ammonium sulphide solution or albumin solutions. If afridol is boiled with hydrochloric acid, an odor of benzoic acid is produced and the cooled solution when saturated with hydrogen sulphide yields a black precipitate of mercuric sulphide. This product is marketed in the form of a 4 per cent soap. Mercurol. — Mercury Nucleinate Mercurol is an organic compound of mercury with nucleinic acid from yeast, containing 10 per cent of metallic mercury. It is prepared by adding METALS AND THEIR COMPOUNDS 981 a solution of mercuric chloride to an alkaline solution of nuclein, contain- ing an excess of alkali, precipitating the resultant nucleinate of mercury by the addition of alcohol and a concentrated solution of a neutral salt (sodium chloride), separating the precipitate, washing and drying it. It is a brownish-white powder, soluble in water, especially in warm water, insoluble in alcohol. Its watery solution has a distinct metallic taste, a weak alkaline reaction, and is not precipitated by alkalies, by albuminous liquids, nor hydrogen sulphide. Mercurol does not coagulate albumin; it has marked bactericidal power and possesses the pharmacologic action of soluble mercury com- pounds. It is recommended as a local antiseptic application and as an anti- syphilitic remedy. Sublamine. — Mercuric Sulphate Ethylenediamine Sublamine, HgSC>4-2C2H4(NH2)2+2H20, is a compound of one mole- cule of mercuric sulphate with two molecules of ethylenediamine. It- forms white needles, readily soluble in water and in 10 parts of glycerin, sparingly soluble in alcohol. It has an alkaline reaction; it contains about 44 per cent of mercury. It does not precipitate albumin from its solutions. Sublamine is a disinfectant. It is used as a substitute for mercuric chloride for hand disinfection, as well as in dermatology, gynecology, ophthalmology, and otology. Electr-Hg. — Electromercurol Electr-Hg is a colloidal suspension of mercury equivalent to .1 per cent metallic mercury and containing a small percentage of sodium arabate. Electr-Hg is prepared by passing an electric current in the form of an arc between two mercuiy electrodes in distilled water. It is made stable by the addition of sodium arabate, which is prepared by acting on acacia (gum arabic) with hydrochloric acid, precipitating the resultant arabic acid with alcohol and neutralizing the arabic acid with sodium carbonate. Electr-Hg is an odorless, tasteless liquid, appearing transparent and brown in color by transmitted light and opaque and gray by reflected light. The addition of potassium cyanide solution or of strong nitric acid yields clear, colorless solutions. The nitric acid solution responds to tests for mercury. Electr-Hg is claimed to have an action similar to that of the soluble salts of mercury. Locally it is said to produce no pain when given by intramuscular injection, and to leave no induration. 982 INORGANIC SECTION Hyrgol is a colloidal form of mercury. It is a nearly black, substance, soluble in water and used for syphilis in the form of ointments and plasters. Calomelol. — Colloidal Calomel Calomelol is a colloidal form of calomel, containing albuminoids. According to the patent, this drug is prepared by acting on a solution of sodium chloride in presence of a proteid with mercurous nitrate and precipitating the colloidal calomel by means of alcohol. The precipitate is washed with alcohol, redissolved in water with the aid of a little alkali, and from this solution the colloidal calomel is obtained either by evapora- tion or by precipitation with alcohol. It forms a white-gray, odorless and tasteless powder, containing 80 per cent of mercurous chloride and 20 per cent of proteids. With water it forms an opalescent suspension insoluble in alcohol, ether, and benzene. It is precipitated from its aqueous suspension by acids, the precipitate being redissolved by alkalies. Determination of Mercury. — The determination of mercury is accom- plished by conversion to the sulphide and weighing, by depositing the metal electrolytically, or by iodin titration. In 1911 the Committee on Quantitative methods of the Pharmaceutical Section of the American Chemical Society suggested the following method for assaying mercury salts, which is applicable to all the mercury compounds of the Pharmacopoeia as well as to other simple salts of mercury. Mercurous Chloride, Bromide and Iodide and Mercuric Iodide. — Weigh out accurately about .2 gram of the sample, dissolve in 20 mils water with the aid of 1 gram potassium iodide. Add 10 mils of 10 per cent sodium hydroxide followed by 3 mils of 40 per cent formaldehyde diluted to 10 mils with water. Warm on the water-bath for ten minutes or until complete precipitation of the mercury takes place, swirling the container occasionally. Decant through a Gooch filter, and wash the precipitated mercury thoroughly with water. Dissolve off the filter with 2 c.c or more concentrated nitric acid, washing the filter carefully with water. From this point the process may be applied also to Mercuric Oxide, by solution in 2 c.c. concentrated nitric acid. Metallic Mercury, Mercury with Chalk and Mercuric Nitrate. — Evaporate the solution to dryness on water-bath and take up with 2 mils concentrated hydrochloric acid and water sufficient to make 50 mils of solution. From this point the process is applicable to Mercuric Chloride by solution as above. Precipitate the mercury from this solution in the cold by a slow stream of hydrogen sulphide, let settle and filter onto a tared Gooch. Wash thoroughly with water and three times with alcohol. METALS AND THEIR COMPOUNDS 983 Wash with recently distilled carbon bisulphide to remove any adhering sulphur, then with alcohol and finally with ether. Dry at 100 to 110° and weigh. HgS X .8621 = Hg. When carefully conducted this method gives good results and it is applicable to almost any pill or tablet containing salts of mercury. B. L. Murray proposes the following electrolytic procedures for assay- ing mercury compounds. If the mercury preparations of the U. S. P. are first converted into mercuric nitrate they are then readily subjected to electrolysis to determine the per cent of mercury. This is practical with mercuiy oxide red, mercury oxide yellow, metallic mercury, and with mercury with chalk. Solution of mercuric nitrate U. S. P. may also be assayed for the mercury present after proper dilution to bring it to the usual concentration. The general statement of the method is to dissolve about 0.5 gram sample in about 1 mil of nitric acid (sp. gr. 1.20), dilute to about 20 mils and subject the solution to electrolysis. Use the mercury cathode and the rotating anode, the latter revolving about 700 to 800 times per minute. The voltage should be 10 to 12, the amperage 3, and fifteen minutes at room temperature will be found sufficient time for the electrolysis to become complete. The mercury cathode is then washed with water, alcohol, and ether in the usual way, any increase in weight being due to the metallic mercury from the weighed sample with which the analysis began. Three-quarters of an hour or one hour easily covers the entire analysis from beginning to end. For ammoniated mercury, mercury iodide red, mercury iodide ^yellow, and mercurous chloride, a different procedure is advisable. These salts are all dissolved in solution of sodium sulphide and from this the mercury is deposited. The samples, about 0.3 to 0.5 gram, are weighed directly into the tared mercury cathode dish. Ten mils of solution of sodium sulphide (sp. gr. 1.18) are added and a current of 0.5 to 0.75 ampere and 4 to 5 volts is passed for half an hour. Use the rotating anode running about 500 revo- lutions per minute. The mercury from the samples is deposited on that of the mercury cathode and all is washed and dried in the usual way with water, alcohol, and ether. If any amalgam of sodium and mercury forms during the electrolysis allow the wash water to stand on it until it is all decomposed. Mercuric chloride is best treated in a simpler manner. To determine the mercury quickly in this place a sample of about 0.3 gram in a weighed mercury cathode dish, dissolve in 20 mils of water, and, after adding a layer of about 10 mils of toluene to protect the apparatus from chlorine gas, pass a current of about 1 ampere and 10 to 11 volts for fifteen minutes. The speed of the rotating anode to be used in this case is about 500 revolu- tions per minute. At the end of fifteen minutes the liquids may as usual 1 J. Ind. & Eng. Chem. 1910, 2, 481. 984 INORGANIC SECTION be removed by decantation and the mercury cathode washed, dried and weighed. Electrolytic Determination of Mercury in Mercury Oleates, Murray. 1 — About .7 to .1 gram of the oleate is weighed directly into a mercury cathode cup (such as a small beaker capacity 50 to 75 mils) . To this sample there are added 15 to 20 mils of 10 per cent hydrochloric acid and 15 mils of toluene. The cathode cup with its contents is placed within a somewhat larger crystallizing dish or beaker which later can be filled with cold water to keep the temperature of the reaction down as desired. After attach- ing the anode and making the connections in the customary way, electrol- ysis of this non-uniform mixture is begun, gradually and slowly increasing the current up to 3 amperes, using about ten minutes to do it. The cur- rent (3 to 3.5 ampers at about 8 volts) is then maintained for about thirty minutes, the anode rotating at about 800 revolutions per minute. As the electrolysis continues, the contents of the cup become heated nearly to the boiling-point of some of the constituents, thus melting the mercury oleate. It is essential that the mercury oleate should melt. If the liquid in the cathode cup becomes too hot and appears to boil over, it should be cooled down by pouring water into the crystallizing dish or other surround- ing vessel, but it should not be cooled down below 60° C. When the mercury is all deposited the cathode cup is washed out by siphonation in the customary way with water, after which the metallic mercury is washed with alcohol, dried with ether, and finally weighed. Electrolytic Determination of Mercury in Mercury Salicylates, Murray. — Put about .3 gram into the mercury cathode dish and dissolve in 10 mils of sodium sulphide solution (sp. gr. about 1.18). To this solution are added 20 mils of 10 per cent potassium hydroxide solution. The mix- ture is now electrolyzed using a current of 1 ampere at 7 volts until the mercury is completely deposited, usually one-half hour being required. The anode should rotate about 500 revolutions per minute. Aiter the deposition the electrolyte is decanted, the mercury is washed with water until free from alkalinity, then with alcohol, finally with ether, and then weighed. Assay of Mercuric Chloride (Antiseptic) Tablets. -R. M. Chapin's 2 method for the analysis of tablets containing mercuric chloride and ammonium chloride. Weigh 5 tablets, dissolve in water, dilute to 100 mils and pass through a dry filter, discarding the first 20 mils of filtrate. From the remainder pipette 10 mils (equivalent to one-half tablet) into a glass-stoppered 250- mil Erlenmeyer flask, add 2| grams pure powdered potassium iodide, mix to entirely dissolve, and then wash down the sides of the flask with 20 mils of normal caustic alkali. Add exactly 3 mils of 37 per cent formaldehyde 1 J. Ind. and Eng. Chem., 8, 1916, 257. 2 Amer. J. Pharm., 1914, 86, 1. METALS AND THEIR COMPOUNDS 985 solution, mix thoroughly, and let stand for at least ten minutes, swirling the flask occasionally. Then wash down the sides of the flask with a mix- ture of 5 mils of 36 per cent acetic acid with 25 mils water; mix, and with- out delay run in from a burette 25 mils of N/10 iodin while constantly swirling the flask. Stopper the flask tightly, shake vigorously for three minutes, then after giving the contents a final swirling motion leave at rest for two minutes. If then no undissolved mercury can be detected at the bottom, the stopper is removed, rinsed, together with the neck of the flask, with a stream from a wash-bottle, and the excess iodin titrated with N/10 sodium thiosulphate, adding starch solution only when the iodin is nearly consumed. Standardize the iodin solution by running a blank assay on 10 mils distilled water. Subtract the volume of thiosulphate solution used in the assay from that used in the blank. The difference jnultiplied by the factor .0271 "^r strictly N/10 sodium thiosulphate will give the average weight of mercuric chloride per tablet. For a direct check upon the value of the sodium thiosulphate solution run an assay on 10 mils of a 2\ per cent solution of mercuric chloride of known purity. While mercuric chloride is the most important active ingredient of tablets made according to Wilson's formula, nevertheless ammonium chlo- ride is an essential part of the formula, added in order to render the tablets easily soluble and to inhibit the formation of insoluble, and hence inactive, compounds of mercury. An assay of such tablets ought therefore to include an estimation of ammonium chloride, especially when a simple and convenient method is available The method for ammonium chloride adopted is an adaptation of the process of Ronchese, which is based on the reaction between formaldehyde and a neutral ammonium salt, whereby methylenamin, (CH^N^ is formed, the acid originally contained in the ammonium salt being released and becoming titratable with standard caustic alkali and phenolphthalein. Titration by standard alkali and phenolphthalein cannot of course be conducted in presence of mercuric chloride. This difficulty, however, is easily overcome by throwing the mercury into a complex ion through the addition of potassium iodide. The method is as follows: Into each of two 150-mil Erlenmeyer flasks pipette 5 mils (one-fourth tablet) of the tablet solution previously prepared for the estimation of mercuric chloride (5 tablets per 100 mils) and add to each flask 2 mils of a 20 per cent solution of potassium iodide. Dilute one volume of 37 per cent formaldehyde solution with three volumes of water, measure 20 mils of the mixture into a small flask, add .5 mil of phenolphthalein indicator solution, neutralize with N/10 barium hydrate or caustic alkali, then flow the solution over the sides of one of INORGANIC SECTION the flasks (flask A) containing tablet solution, and mix well. To the other flask (flask B) containing tablet solution add about 65 mils water. Now add to the flask A 25 mils water and titrate with N/10 barium hydrate or N/10 caustic alkali free from carbon dioxide until, by using flask B as a standard for comparison, a color change is perceptible (titra- tion A). Add methyl red to flask B and titrate with either N/10 acid or alkali as needed (titration B) . To titration A add titration B if performed with acid, or subtract if performed with alkali. The resultant figure multiplied by the factor .0214 for strictly N/10 alkali will give the average weight of ammonium chloride per tablet. For a direct check upon the value of the N/10 alkali run an assay upon 5 mils of a 2J per cent solution of pure ammonium chloride. Solutions, reagents, and water used should be free from carbon dioxide. Ordinarily titration B is very small, sometimes zero, but usually calling for the addition of a few drops of N/10 acid. As respects the end-points with the indicators it is only possible to state that up to the present time no blue or green tablets tested by the originator presented the slightest difficulty. The characteristic colors of the indicators of course do not appear in the presence of other coloring matter, but the change of tint, if standards of comparison are used, is delicate and distinct. Method for Determination of Mercuric Iodide in Tablets, A. W. Bender. 1 — Powder a sufficient number of tablets to represent 1 to 2 grains of iodide. Place in a 180-mil Erlenmeyer flask and add 20 mils 1-1 hydro- chloric acid. Add about .5 gram potassium chlorate and stopper with glass tube reflux condenser. Digest on sand-bath until iodide is all dis- solved. Cool and dilute with water to about 100 mils, removing and wash- ing condenser. Blow out chlorin with a current of air. Filter and wash insoluble matter by decant at ion. Add excess of ammonia, and precipi- tate immediately in the cold with a slow stream of hydrogen sulphide. Let stand for a few hours and filter onto a weighed Gooch, washing with water, etc., and drying as described above in determining mercury as sul- phide. Grams of HgSX 30. 17 = grains Hgl 2 . HgXl.955 = HgI 2 Mercurial Ointments About 2 grams of the ointment are warmed with petroleum ether and treated with 15 to 25 mils N/10 iodin. The mixture is heated until the mercury and mercuric oxide are dissolved, after which it is transferred 1 J. Ind. and Eng. Chem., 1914, 6, 753. METALS AND THEIR COMPOUNDS 987 to a separator, the iodin solution drawn off and the petroleum ether layer washed with water. The combined aqueous and iodin solutions are then treated with excess of potassium hydroxide, and the mercury precipitated by the addition of 3 mils formaldehyde 40 per cent and warming. The balance of the determination from this point follows either of the two outlines above described. Determination of Mercuric Iodide in Ointments. — Hallaway x recom- mends warming 2.5 grams with potassium iodide solution, and the melted ointment shaken until the red color disappears. After cooling, the liquid is filtered into a stoppered flask, and the treatment of the ointment base repeated twice. Twenty mils of potassium hydroxide are added, followed by 3 mils of formaldehyde, and the mixture warmed and whirled. After one-half hour 25 mils of 33 per cent acetic acid are added, followed by 25 mils N/10 iodin, the mixture shaken until the mercury is dissolved, and the excess of iodin titrated as in the Chapin method for tablets. Determination of Mercury and Iodin in Antiseptic Soaps, A. Seidell. 2 — About 10 grams of the soap is weighed into an Erlenmeyer flask and treated with 150 mils of 95 per cent alcohol and 3 to 5 mils con- centrated hydrochloric acid. The solution is warmed and successive small portions of water added until a perfectly clear solution is obtained on shaking. If suspended particles are present, the solution should be filtered. A slow stream of hydrogen sulphide is then passed through the liquid for about an hour, and the sulphide is collected on a carefully pre- pared Gooch crucible. The fatty material present in the solution appears to have a tendency to cause the precipitate to pass through the filter, but no trouble on this account need be experienced if care is taken to use the least amount of suction possible until the precipitate has been washed several times with 95 per cent alcohol. The sulphide is then washed with carbon disulphide, alcohol, and ether, dried at 100 to 105° and weighed. The filtrate and alcoholic washings from the sulphide are concentrated to about one-third, water added to replace the evaporated alcohol, the solution cooled and filtered from the separated fatty acids into a separatory funnel; 25 to 50 mils chloroform are added, the iodin liberated by the addition of a few drops of nitrous acid, and dissolved in the chloroform by shaking. The chloroform is then drawn off and a fresh portion added and shaken, and the procedure repeated until the whole of the iodin is removed. The combined chloroformic solutions are washed with water, and the washings shaken with fresh chloroform to recover any iodin which may have been taken up by them. Finally the chloroform solution is titrated with standard sodium thio sulphate. The nitrous acid solution is prepared by adding to a mixture of about 10 grams of starch and 10 grams of arsenous acid contained in a 700-mil 1 Pharm. J., 86, 405. 2 J. A. Chem. Soc, 1906, 28, 73. 988 INORGANIC SECTION Erlenmeyer flask, about 150 mils nitric acid of 1.3 sp. gr. The solution is warmed gently and the reddish fumes conducted into a bottle contain- ing 100 mils of concentrated sulphuric acid. Determination of Mercuric Chloride in Surgical Dressings, R. Guiter. 1 About 50 grams of the compound are mixed with about 250 mils of water in a 750-mil flask and well shaken for a few minutes; 5 grams of potassium iodide in solution are added and the whole shaken for ten minutes; 50 mils of 10 per cent sodium hydroxide are then added, followed by 25 mils of 40 per cent formaldehyde; after shaking again, for ten minutes 12 mils glacial acetic acid are added and 15 mils of N/10 iodin; after shaking again for ten minutes the excess of iodin is determined by titration with N/10 sodium thiosulphate. Mercury in Organic Compounds The determination of mercury in organic combination can be effected by decomposing the organic matter with sulphuric and nitric acids and, after removing any residual nitric acid by evaporation, neutralizing with ammonia, precipitating the mercury as sulphide in presence of dilute hydro- chloric acid. If the circumstances warrant, the decomposition of the product may be effected in a Carius tube with fuming nitric acid, the heat being raised to a temperature of 160 to 180° for six to eight hours. After evaporating the solution, the residue is treated with dilute hydrochloric acid and the mercury precipitated as sulphide. Separation of Mercury from Other Metals. — Calomel may be separated from bismuth subcarbonate by dissolving out the latter with dilute hydro- chloric acid. The calomel is then collected on a Gooch, washed, dried, and weighed. If the tablet contains excipient insoluble in dilute acid, the calomel is then brought into solution with potassium iodide, precipitated with formaldehyde in presence of sodium hydroxide, and the precipitated mercury dissolved in acid and finally determined as sulphide, or dissolved in iodin solution in presence of acetic acid and the excess of iodin titrated. The bismuth in the filtrate is precipitated either as the trisulphide, carbonate, or chromate, as detailed under Methods for Determining Bismuth. Calomel and zinc sulphocarbolate are separated by dissolving out the zinc salt with water. Bismuth subnitrate is separated from mercury and chalk by solution in dilute hydrochloric acid. When mercury occurs with arsenic and iron, a solution of the sample acidulated with dilute hydrochloric acid, is precipitated with hydrogen sulphide. The filtrate contains the iron, which is converted into the ferric state, after boiling off the excess of hydrogen sulphide, and precipi- 1 Pharm. Zeit. 1910, 427. METALS AND THEIR COMPOUNDS 989 tated as hydroxide. The combined sulphides of mercury and arsenic are then digested with yellow ammonium sulphide, which dissolves the arsenic sulphide, and the residual mercury sulphide collected on a Gooch and, after the customary washing, weighed. Mercury can be separated from copper and arsenic by precipitation with phosphorous acid in presence of hydrochloric acid. The mixture is allowed to stand in the cold for twelve hours, at the end of which period the precipitated calomel is collected on a Gooch, washed with water, dried, and weighed. When mercury occurs with gold and arsenic, a solution of the sample free from nitric acid is treated with a clear freshly prepared solution of ferrous sulphate in the presence of a little hydrochloric acid, heated gently for a few hours until the precipitated fine gold has completely settled, filtered; and washed. The gold collecting on the filter, may be ignited and weighed, the filtrate subjected to the treatment with hydrogen sulphide, and the mercury separated from the arsenic as described above. Mercury can be separated from copper and arsenic by treating a solu- tion of the sample with 25 to 30 mils of saturated tartaric acid, stirring for one to two minutes, adding potassium cyanide in small amounts at a time until the solution becomes clear, stirring continually. The mercury is then precipitated with hydrogen sulphide in the cold. COPPER Copper salts are used in medicine because of their astringent, anti- septic properties and tonic values. They are used in remedies for diarrhea and other intestinal affections, for eye troubles, ringworm, ulcers, gonor- rhea, syphilis, and in remedies for diseases of poultry, especially roup. Copper sulphate and carbonate are antidotes in phosphorus poisoning. Copper oxide, CuO, is used internally for expelling tapeworm. The acetate, arsenite, nitrate, oleate, citrate, and phosphate are all used as remedial agents. The citrate is used in ointment form for eye troubles, and is recommended for trachoma. Nucleid of copper is known as cuprol. Copper arsenite is combined with calomel and morphin, and copper sulphate is combined with opium. The determination of copper may be accomplished electrolytically or volumetrically. In most medicinal preparations, copper is present in the form of an inorganic salt, and in order to remove the metal from extraneous substances, the sample should be warmed with dilute hydrochloric acid, filtered, and precipitated with hydrogen sulphide. The copper sulphide is then filtered, washed with water and dissolved in hot dilute nitric acid. The determination is finished either electrolytically or volumetrically. Electrolytic Estimation. — The solution obtained as above, described is collected in a beaker of about 250-mils capacity, and two platinum elec- 990 INORGANIC SECTION trodes lowered into the liquid, the anode being a length of platinum wire, and the cathode a platinum cone or crucible. A crucible, into the mouth of which is inserted a rubber stopper which in turn is connected with a rotating spindle, will give the best results. The apparatus described below FRONT ELEVATION SIDE ELEVATION will be found serviceable, and is indispensable to a well-equipped laboratory where it is necessary to perform a number of assays of copper or tin. A current of .5 and 1 ampere passed through the copper solution will give satisfactory results. The deposition of the copper is completed when, on lowering the spindle so that a clean surface of platinum is immersed, no further coloration appears. The crucible is then detached, washed with METALS AND THEIR COMPOUNDS 991 distilled water, and alcohol and dried at 100° for a few minutes. The gain in weight is due to the metallic copper. Volumetric Estimation. — The hot solution is treated with sodium car- bonate solution 1 per cent until a slight permanent precipitate is formed. Acetic acid is added until the precipitate is dissolved and the solution is perfectly clear. The solution is cooled and potassium iodide added in considerable excess. Each 1 gram copper requires .527 gram potassium iodide and the solution should contain at least 1 gram in excess. As soon as the precipitated cuprous iodide has settled, the iodide is titrated with standard sodium thiosulphate. 2(CH3COO) 2 Cu+4KI = 4CH3COOK+Cu 2 l2+l2 The determination of copper in organic combination presents no serious difficulty as the organic matter can be destroyed, or at least separated from the copper, by digestion with sulphuric and nitric acid. This treat- ment is applicable to ointments. GOLD Auric chloride, AUCI3, is used as a remedy for consumption, tubercular affection, and lupus. A mixture of equal parts of gold chloride and sodium chloride (gold and sodium chloride U. S. P.) is used in syphilis, cancer, hysteria, neuralgia, and rheumatism, and is the form in which the metal is usually administered for the treatment of inebriety. Aurous iodide, Aul, and aurous cyanide and auric cyanide, Au(CN)3+3H20, are used in the treatment of scrofula and tubercular diseases. Aurous bromide and auric bromide are used as anodynes, nervines and anti-epileptics. Auric oxide, AU2O3, is an alterative, and is used in scrofula and tuberculosis. Potassium cyanaurate, KAu(CN)2, (gold and potassium cyanide) is an active antiseptic. Collaurin is a name given to colloidal gold. Gold salts are often present in treatments for the liquor and tobacco habits, and are combined with a variety of sedatives and narcotic drugs. In many of these remedies the quantity of gold present is exceedingly minute, and will usually be overlooked unless a special test is performed to establish its presence. Some of the combinations listed include pill formulas where gold and sodium chloride are present with the valerianates of zinc, iron, and quinin; with arsenous acid, with arsenic chloride, and quinin ■ with phosphorus, Nux Vomica, and damiana. Auric bromide is combined with bromides of arsenic and mercury in solutions. The quantity of gold in remedial agents is often so small that its pres- ence might easily be overlooked. In fact it may be necessary to perform 992 INORGANIC SECTION special tests to determine its presence in many instances. Solutions con- taining gold salts are reduced by ferrous sulphate; weak solutions yielding a bluish coloration, stronger mixtures a brown precipitate. Oxalic acid, on being gently warmed with gold salts, causes the deposition of the metal, either as a scaly precipitate or as a coherent gold film. Stannous chlo- ride gives a precipitate or coloration (depending on the concentration) varying in color from reddish brown to purple. The presence of a trace of stannic chloride facilitates the production of the purple. U. S. P. Assay of Gold and Sodium Chloride. — .5 gram of the substance is dissolved in 25 mils of water in a porcelain dish, 5 mils potassium hydrox- ide added and 5 mils hydrogen peroxide. The mixture is heated for one-half hour on a water-bath, washed with water slightly acid with hydro- chloric acid, dried, ignited in a porcelain dish, and weighed. The residue should not be less than .15 gram, corresponding to at least 30 per cent of gold. To determine the gold in pills, the ground material should be boiled with aqua regia, the solution diluted if necessary to filter off any insoluble matter, and the clear filtrate evaporated on a water-bath to the consistency of syrup, adding from tune to time hydrochloric acid. The residue is dis- solved in water containing hydrochloric acid, and an excess of freshly pre- pared clear solution of ferrous sulphate added. It is then heated gently for a few hours until the precipitated gold has completely settled, filtered, washed, ignited in a porcelain crucible or dish, and weighed. If the sample contains iron which it is desired to determine subse- quently, or if it is important to have a filtrate free from this metal, the gold may be reduced by oxalic acid. The dilute solution, freed from nitric acid as above described, is mixed in a beaker with oxalic acid or ammonium oxalate in excess, sulphuric acid added and the beaker, covered with a watch-glass, is allowed to stand for two days in a moderately warm place. The separated gold is collected in a filter, washed and ignited. If the gold solution contains a large excess of hydrochloric acid, the latter should be for the most part evaporated before the solution is diluted and oxalic acid added. If chlorides of the alkali metals are present, it is necessary that the dilution be considerable, and the time of precipitation lengthened. BISMUTH The well-known salts of bismuth, the subnitrate and subgallate, are valuable remedial agents for inflammatory conditions of the mucous mem- brane, especially of the alimentary canal; the subgallate (dermatol) is used in the local treatment of eczema, ulceration and wounds in place of iodoform; and the organic combinations are usually employed where it METALS AND THEIR COMPOUNDS 993 is desired to combine the soothing and protective actions of the bismuth with an antiseptic. Bismuth and ammonium citrate is astringent in action, and is the form in which bismuth is usually present in elixirs. Double citrates of bismuth and lithium and of bismuth and iron are soluble scale salts. The subnitrate and subcarbonate are dispensed in the form of pills, tablets, and powders, and the formulas often include the digestive ferments pepsin and pancreatin, with ginger and Nux Vomica. The subnitrate is also combined with calomel; with calomel and ipecac; with calomel, salol, and sodium bicarbonate; with cerium oxalate; with guaiacol carbonate; with camphor, opium, salol, and oil of peppermint; with charcoal; with opium and carbolic acid; with opium, Krameria, and licorice; with cerium oxalate and cocain. Bismuth subgallate will be found in a few tablet formulas with Nux Vomica and digestives, and in dusting powders. The elixir formulas containing bismuth and ammonium citrate will be found to contain in addition strj'chnin, the Cinchona alkaloids, ferric pyrophosphate, saccharated or lactated pepsin, and pancreatin. Bismuth salicylate has a limited use, principally in intestinal trouble. Milk of bismuth, or lac bismuth, is a suspension in water of a bismuth salt, usually the subcarbonate with more or less hydroxide. Bismuth oxide is prepared in colloidal form. It is sold under trade- mark names, " Bismon " being representative of the class. It forms an opalescent colloidal suspension with water, which is not precipitated by hydrogen sulphide unless acid is present. A solution of egg albumin produces a precipitate which dissolves in excess of the albumin solution. Tannismuth is bitannate of bismuth, containing between 17 and 21 per cent of bismuth. Bismuth betanaphtholate, known as Orphol, is a brownish or grayish powder insoluble in water and chloroform, and slightly soluble in alcohol. It is gradually decomposed on shaking with mineral acids, and the naphthol may be recovered by shaking out with chloroform. For assaying the salt, the following procedure is used : From 1 to 2 grams are shaken in a separator during one hour with 25 mils chloroform, and 25 mils concentrated hydrochloric acid; 50 mils of water are then added, and the mixture again shaken. The chloroform layer is then drawn off, the acid solution shaken with three portions of 10 mils of chloroform, and the combined extracts evaporated and dried over sulphuric acid, the weight amounting to at least 15 per cent. The acid solution is transferred to a beaker, diluted with water to 200 mils, heated to boiling, ammonia added until a turbidity appears, then sufficient hydrochloric acid to clear up the turbidity, and finally 50 mils of 10 per cent ammonium phosphate. When the precipitate has subsided the clear 994 INORGANIC SECTION liquid is decanted through a tared, ignited Gooch crucible, the precipitate washed by decantation with boiling water and finally transferred com- pletely to the Gooch. It is then dried, suspended in a nickel crucible, and exposed to the full heat of the Bunsen flame until the weight is constant. The weight of the bismuth phosphate multiplied by .6869 should yield a figure representing metallic bismuth, equal to not less than 60 per cent of the material taken. Crurin is quinolin-bismuth sulphocyanate (C9H7N-HSCN)3Bi(SCN)3. It is a bluish-red substance, insoluble in alcohol and ether, but soluble in acetone, and slightly in glycerin. It is decomposed by water. It dis- solves in dilute nitric acid, yielding a solution from which bismuth can be precipitated with hydrogen sulphide, and in which the sulphocyanide content can be determined by titration with standard silver nitrate. Airol— Bismuth Oxyiodogallate. Airoform, C 6 H 2 (OH) 3 (COOBiI(OH) ) is a combination of bismuth oxyiodide (subiodide) and gallic acid. It is prepared by heating molecular quantities of bismuth subgallate and hydriodic acid or bismuth oxyiodide and gallic acid, in the presence of water, until a grayish-green product results, which is drained and dried. It is a voluminous grayish-green, odorless, and tasteless powder, insolu- ble in alcohol, ether, chloroform, and olive oil, slightly soluble in glycerin. It is practically insoluble in water, communicating to water a red color on standing, slowly in the cold, but readily when heated, being decomposed with liberation of iodin and bismuth subgallate. It is readily soluble, with decomposition, in dilute alkalies and mineral acids. It is decomposed on exposure to moist air, turning red, but in admixture with glycerin and a little water it long remains unaltered. Bismal, 4(Ci 5 Hi 2 Oio), 3Bi(OH) 5 is a compound of bismuth hydroxide and methylendigallic acid. It is obtained by digesting 4 molecules of methylendigallic acid with 3 molecules of bismuth hydroxide in water. It is a voluminous gray-brown powder, insoluble in water or gastric juice, but soluble in alkalies, forming yellowish-red solutions. Xeroform-Tribromphenol-Bismuth Xeroform is basic bismuth tribrom-phenolate, Bi(C6H 2 Br30)20H • Bi 2 03, containing nearly 50 per cent of B12O3. According to the patent it is obtained by dissolving tribromphenol in sodium hydroxide and adding bismuth nitrate to the sodium tribrom- phenolate solution. The precipitated tribromphenol bismuth is collected, and washed with alcohol. METALS AND THEIR COMPOUNDS 995 It is a fine yellow, nearly odorless and tasteless powder, neutral in reaction, and unaffected by light. It is insoluble in water, alcohol, chloro- form liquid petrolatum, and vegetable oils, but soluble in 2 per cent, hydrochloric acid in the proportion of 30 : 100. By alkalies it is decom- posed with the formation of bromides; it is not decomposed by heat at temperatures below 120° C, and therefore may be sterilized. It should yield 49.5 per cent of bismuth oxide. If 1 gram is boiled with sodium hydroxide T. S. filtered, the filtrate rendered acid with sul- phuric acid and the white, curdy precipitate washed and dried, it should melt at 95° C. (tribromphenol) . Bismutol is bismuth and sodium phosphosalicylate. Helcosol is a basic compound of bismuth and pyrogallol, a yellow amorphous powder soluble slightly in very dilute hydrochloric acid, insoluble in water and alcohol. Dermol is a combination of bismuth and chrysophanic acid, probably a basic salt. It is a yellow amorphous powder, insoluble in water and alcohol, but dissolving in nitric or sulphuric acids. Biodal is stated to be monoiododibismuthmethylenedicresotinate. It is a pink, odorless, tasteless, insoluble powder. Bismutose is a bismuth-albumin compound soluble in alkalies and slightly in dilute acids, but insoluble in water. Assay of Bismuth Salts. — The bismuth content of bismuth subnitrate and subcarbonate is determined by igniting the sample in a porcelain crucible to constant weight. The Bi2C>3 in the subnitrate amounts to not less than 79 per cent and in the subcarbonate not less than 90 per cent. Organic salts are ignited in the same way until there is no further change in the appearance of the blackened residue. The crucible is cooled a few drops of concentrated nitric acid added, the acid evaporated over the steam-bath, and the residue carefully ignited to constant weight. Determination of Bismuth in Mixtures. — Bismuth is determined in elixirs or in solutions of its soluble salts by evaporating the sample to dryness in a porcelain dish and igniting. The residue is then treated with concentrated nitric acid, and after the reaction due to solution of the bis- muth or its oxide has ceased, the contents of the dish are warmed on the steam-bath, diluted sufficiently to prevent the acid from acting on filter paper, but not until the basic bismuth salt is thrown out; the solution filtered and washed with warm dilute nitric acid Ammonium carbonate, is added in very slight excess, heated nearly to boiling for some time, filtered onto a tared Gooch, washed with water, dried and ignited to con- stant weight. When iron accompanies bismuth, the procedure should be modified. The ignited residue is dissolved in nitric acid, filtered, and evaporated until the excess of acid is drawn off. The residue is dissolved in sufficient 996 INORGANIC SECTION hydrochloric acid to hold up the oxy chloride of bismuth, and subjected to the action of hydrogen sulphide until the bismuth is completely pre- cipitated. The sulphide of bismuth is then collected on a filter and well washed with water, the filtrate and washings being preserved, if desired, for the subsequent determination of the iron. The filter paper and sul- phide of bismuth are then transferred to a beaker, treated with diluted nitric acid 1-1 and heated until the bimuth is dissolved. The solution is filtered, washing through the filter with dilute nitric acid, the filtrate and washings precipitated with ammonium carbonate, and the determi- nation completed as above described. The bismuth content of the milk of bismuth preparations can in most instances be determined by evaporating off the water, igniting the residue, and weighing the bismuth oxide. If the composition is unusual, or impurities occur in the bismuth precipitate, it may be necessary to dissolve the basic salt in hydrochloric acid and precipitate with hydrogen sulphide, completing the determination in the usual way. Powders containing bismuth salts in combination with digestives, antiseptics, and sodium bicarbonate should first be ignited to decompose the organic matter. The bismuth salt is then dissolved out with nitric acid and determined as usual. In powders or tablets with calomel, bismuth salts are determined by first dissolving them in diluted hydrochloric acid in order to separate them from the calomel. The bismuth is thrown out of the filtrate as sulphide, and the determination continued. When bismuth salts occur in complex tablet mixtures, the determi- nation of the metal can usually be effected by burning off the organic matter by gentle ignition, treating the residue with concentrated nitric acid, and continuing to the procedure for elixirs. If zinc or other heavy metals are present, it will be necessary to evaporate the nitric acid solution to dryness, dissolve the residue in diluted hydrochloric acid, and throw out the bismuth as sulphide. Bismuth may be determined as the trisulphide, by collecting the pre- cipitated sulphide on a tared Gooch, washing with water, alcohol, ether, carbon bisulphide free from sulphur and finally alcohol and ether. The Gooch is then placed in a drying oven at 100° for fifteen to twenty minutes, cooled in a desiccator and weighed. There should be as little exposure as possible to the air at 100° C, as the sulphide absorbs oxygen and gains in weight Bi 2 S3X.9061 = Bi 2 O3. Bismuth can be determined by precipitation as phosphate as described in the Assay of Orphol. The formation of the chromate furnishes a satisfactory means of determining bismuth. The bismuth is freed from other substances by the methods described above, and a solution which is as neutral as possible METALS AND THEIR COMPOUNDS 997 is poured, with constant stirrng, into an excess of a warm solution of potassium bichromate in a porcelain dish, washing out the vessel which contained the bismuth solution with water containing nitric acid. The precipitate should be orange yellow and dense throughout; if it is floc- culent and has the color of egg yolk, there is a deficiency of bichromate and a fresh quantity of the latter must be added, and the mixture boiled until the precipitate has the proper appearance. The mixture is boiled for ten minutes and the clear supernatent liquid decanted through a tared Gooch; the precipitate is boiled with water, repeatedly decanting the washings through the Gooch, and finally collected on the filter. It is dried at 120° and weighed as Bi2(V2Cr03. Bismuth in Bismuth-/3-Naphtholate-Electrolytic Determination, Murray. 1 — A sample of .3 gram is weighed into a porcelain crucible and heated very gently to decomposition of the 0-naphthol. The crucible is finally heated to the full red heat of a Meker burner for three minutes to burn off the last traces of carbon. The residue resulting is j^ellow in color and is composed chiefly of bismuth oxide together with a small quantity of metallic bismuth. The crucible is placed in a small beaker and a mixture of 4 mils of nitric acid (sp. gr. 1.4) and 5 mils of water is added, after which it is heated on a steam-bath to complete solution. The solution is washed with distilled water into a mercury cathode cup, keeping the volume down to 20 mils. The cathode cup is conveniently made from a 50-mil Erlenmeyer flask. The 20 mils solution is then electrolyzed under the following conditions: Current (maximum) 4.5 amperes at 6 volts. Revolutions per minute 1000. Tune forty-five minutes. The initial application of the current is 1 ampere and this is followed by a gradual increase to 4.5 amperes. Some black masses are seen to form, but rapid rotation of the anode prevents the formation of a large quantity and all disappear, when the black masses have stopped and the cathode is washed with distilled water by siphonation while the full strength of a current is on. The electrolyte should be tested for bismuth with hydrogen sulphide. After two to three washings with water, followed by alcohol and then by ether, the mercury cathode is weighed. The increase in the weight of the mercury cathode is due to the bismuth which has been deposited on and amalgamated with the mercury. ARSENIC Arsenous oxide is one of the ingredients of alterative, tonic and anti- periodic remedies which are prescribed in intermittent fever, chorea, chronic rheumatism, chronic syphilitic and cancerous diseases, etc. It 1 J. Ind. and Eng. Chem., i, 1916, 258. 998 INORGANIC SECTION is dispensed alone, and often in combination in pills and tablets with reduced iron, ferrous carbonate, strychnin, and quinin. Some of the other combinations of arsenous oxide include the following, with chinoidin, oleoresin pepper, and iron ferrocyanide (anti-chill mixture) ; with quinin, ferrous sulphate, Gelsemium resin, Podophyllum resin, and oleoresin pep- per; with powdered black pepper, acacia, and althea; with quinin, oleo- resin of Capsicum, zinc oxide, and strychnin; with extract of Eucalyptus, chinoidin, iron ferrocyanide, and Capsicum (fever and ague) ; with quinin, morphin, strychnin, and aconite; with quinin, Taraxacum, and ferrous sulphate; with Sumbul, asafetida, and ferrous sulphate; with quinin, strychnin, ipecac, and reduced iron; with extract Cannabis sativa and reduced iron; with ferrous carbonate, strychnin, and Hyoscyamus; with strychnin, ferrous sulphate, mercuric chloride, and potassium carbonate; with quinin, acetanilid, strychnin, Hyoscyamus, and Cannabis sativa; with ferrous sulphate, valerian, Sumbul, and asafetida; with sulphur, potassium bitartrate, sodium benzoate, ipecac, and Capsicum; with quinin, strychnin, gentian, and reduced iron; with quinin, ferric chloride, gold, and sodium chloride; with ferrous carbonate, Nux Vomica, and Cascara; with quinin, reduced iron, strychnin, and Cascara. Arsenous oxide is sold in capsule form with cod-liver oil, creosote, atropin, and strychnin. In the elixir form it is combined w r ith iron pyrophosphate and quinin sulphate. Solution of arsenous acid U. S. P. is a 10 per cent solution of arsenous oxide in dilute hydrochloric acid. Fowler's solution or solution potassium arsenite is prepared by dis- solving arsenous oxide and potassium bicarbonate in water, and adding compound tincture of lavender. Arsenous oxide is a component of rat poisons. Arsenic tribromide or arsenous chloride is recommended in diabetes, and is used alone and in combination with bromides of gold and mercury. Clemens' solution is prepared by adding bromin to a solution of potas- sium arsenite containing 1 per cent AS2O3. The title " solution of bromide of arsenic," which is often applied to some of the preparations, is some- what misleading, as arsenic bromide is decomposed by water into hyclro- bromic and arsenous acids. Pearsons' solution is a 1/10 per cent solution (approx.) of sodium arsenate. Arsenous chloride is found in tablets combined with the chlo- rides of ammonium and iron and quinin hydrochlorate; and with the chlorides of iron and mercury and quinin hydrochlorate. Arsenous iodide is used internally for the treatment of skin diseases, and externally as an ointment for the reduction of tubercular swellings. It is combined with mercuric and ferrous iodides ; with the iodides of mer- METALS AND THEIR COMPOUNDS 999 cury, iron, and potassium, mercuric chloride, and Nux Vomica. Dono- van's soution is a 1 per cent aqueous solution of arsenous and mercuric iodides. Arsenous sulphide is used internally for diseases of the skin. Arsenic peptonate is often found in combination with the peptonate mixtures of iron and manganese. In a discussion of the organic substances containing arsenic in combi- nation the analyst is referred to the chapter on page 873. Arsenous oxide is assayed according to the Pharmacopoeia by treat- ing .1 gram with 1 gram sodium bicarbonate, dissolving in 20 mils water with the aid of gentle heat, and titrating with N/10 iodin, of which not less than 20.3 mils should be required. For the assay of the solution arsenous acid, 24.6 grams are treated with 2 grams sodium bicarbonate and 100 mils water and titrated with N/10 iodin, of which not less than 50 mils should be required. For the assay of Fowler's solution 24.6 grams are diluted with water to 100 mils, slightly acidified, then made alkaline with sodium bicarbo- nate, and titrated with N/10 iodin, of which not less than 50 mils should be required. The arsenous oxide in rat powders can be estimated by weighing out from .2 to 5. gram, mixing with 1 to 2 grams sodium bicarbonate and transferring to a 100-mil graduated flask with 25 mils water, the flask is warmed gently, but not sufficiently to gelatinize any starch which may be present. After thoroughly shaking, the contents are made up to 100 mils, and aliquots of 10 to 25 mils filtered off and titrated with N/10 iodin. The estimation of arsenic in pills, tablets, and other mixed remedies, may be conducted as described in the chapter on General Methods. When iron occurs with arsenic, and this is usually the case with medi- cinal preparations, the advisability of depending absolutely on the evolu- tion determination may become a matter of moment, as it has been claimed that iron holds back some of the arsenic. This question is almost certain to come up in court, if the method has been used in the analysis of the preparation on which the case is based. It is probable that one will obtain all of the arsenic in the mirror from a given quantity of aliquot taken, provided he runs the determination over a sufficiently long period, and the aliquot used does not contain too much arsenic. It is advisable to run several determinations with the same solution, using different amounts, say 5, 10, 15, 20-mil portions, and note whether they check or not. As a confirmatory measure and when it is desired to determine the amount of iron present the solution containing the metals, free from organic matter, is neutralized with alkali and acidulated with hydro- chloric acid. Hydrogen sulphide is passed through the mixture, which is kept warm during the treatment, until the arsenic is entirely precipi- 1000 INORGANIC SECTION tated. The precipitation will be slow at first, as all of the arsenic is in the higher state of oxidation. When there is apparently no further precipi- tation of arsenic sulphide and sulphur and the liquid is well saturated with the gas, it is well to stopper the container and allow it to digest overnight. The sulphide and sulphur are then collected on a filter, well washed with water, and the filtrate and washing set aside for the iron determination. The filter is transferred to a beaker, covered with strong nitric acid, and heated until the sulphide has dissolved and most of the sulphur has been oxidized. The solution is somewhat diluted, a crystal or two of potassium chlorate added, and gently warmed until the odor of the gas has nearly disappeared. The solution is filtered, washed with water, the filtrate and washings treated with ammonia which must produce no precipitate or turbidity. An excess of magnesia mixture is added gradually with constant stirring and the solution allowed to stand at least twenty-four hours, after adding a further quantity of ammonia. The ammonia- magnesium arsenate is collected on a filter, washed with a mixture of ammonia and water 1 in 3. After drying the precipitate is transferred to a porcelain crucible, the filter burned and the ash added to the contents of the crucible, and the whole ignited to constant weight. Mg2As2C>7. ANTIMONY COMPOUNDS Antimony salts have long been used in medicine, and some of the old-time preparations which are obsolete for the treatment of human beings are employed in veterinary practice. Antimony and potassium tartrate or Tartar Emetic is the salt most commonly employed as a medicinal agent, and is present in expectorant diaphoretic, alterative, and emetic compounds. Some of the more impor- tant formulas consist of this salt with mass of mercury, aloes and jalap (Cole's dinner pills); with ammonium chloride and Hyoscyamus; with ammonium chloride, morphin and Sanguinaria; with morphin and aconite; with morphin, aconite, and ipecac; with licorice, benzoic acid, opium, camphor, and anise oil; with ammonium chloride, senna, licorice, and sulphur; with ipecac, Sanguinaria, morphin, atropin, and aconite. Wine of antimony is a solution of. tartar emetic in wine; and compound syrup of Squill contains senega and tartar emetic. Tartar emetic is a component of a certain type of plaster designed to produce the pustulating effect of the emetic. The base of these plasters is usually Burgundy pitch and colophony. Sulphurated antimony or Kermes minerals is a mixture of sulphides and oxides of the metal. It is used as an alterative, diaphoretic, and emetic. Plummer Pills, a classic formula, contains Kermes mineral, calomel, and guaiac. It is also combined with ipecac and morphin; and with aconite, bryonia, belladonna, and potassium bichromate. METALS AND THEIR COMPOUNDS 1001 Antimonial saffron, Crocus Metallorum, consists chiefly of antimony oxysulphide, Sb 2 S 3 +Sb 2 OS 2 . Antimony sulphide, SD2S3, and antimonic sulphide, SD2S5, the golden sulphide, are used in veterinary remedies. Antimonous oxide, SD2O3, is an expectorant and emetic, and is the active constituent of Antimonial powder or James' Powder (Pulvis Jacobi), a mixture with precipitated calcium phosphate. Antimony chloride, SbCl3, is used as a local application for snake bites, wounds, syphilitic ulcers, warts, and excrescences. Antimony iodide, Sbl3, is employed in catarrh. Antimony, when present in simple mixtures or alone as antimonous oxide, as for instance in James' powder, can be determined by titration with iodin. The powdered material amounting to about 2 grams is weighed accurately, introduced into a 250-mil graduated flask, treated with 2 grams of tartaric acid dissolved in 25 mils water, and the mixture shaken gently for sufficient time to dissolve the oxide. Sodium carbonate is added until the solution is just neutral, and the liquid made up to 250 mils. After settling, a 50-mil aliquot is drawn off into a flask and titrated with N/10 iodin. 1 mil = .0072 gram Sb 2 3 . Sb203+2H 2 0+2l2 = HI+Sb 2 05 When antimony salts are present in pills or tablets, the sample should be well pulverized, introduced into a 250-mil graduated flask, covered with concentrated hydrochloric acid and warmed. When ebullition ceases, the solution is made up to the mark with 5 per cent tartaric acid solution and after settling, aliquots of 5 mils are drawn off, heated nearly to boiling, and hydrogen sulphide conducted through the liquid, keeping the liquid fairly hot during the passage of the gas. When thoroughly saturated, the flask is stoppered and allowed to remain in a warm place overnight. It may sometimes happen, where the quantity of antimony is small, that no precipitate will appear until the mixture has stood for some time. The sulphide is then collected on an ashless filter, washed with hydrogen sulphide water, and the filter and precipitate transferred to a tared porcelain crucible with concave lid. About eight to ten times the quantity of fuming nitric acid is added and the acid slowly evapo- rated on the water-bath. If charring occurs after the nitric acid has evaporated, a few more drops of the latter are added, and the evapora- tion repeated, and the procedure continued until no further blackening occurs. The residual mass in the crucible consists of antimonic and sul- phuric acids, and on careful ignition is converted to antimony tetroxide, Sb 2 4 . If the sulphide of antimony carries down much sulphur, the precipi- tate on the filter should be washed with alcohol, ether, and carbon bisul- 1002 INORGANIC SECTION phide, and then with alcohol before being subjected to the acid digestion. If mercury is simultaneously present, the sulphide precipitation may contain mercury, and in this event the filter paper containing the mixed sulphides is spread out in a porcelain evaporating dish and digested with yellow ammonium sulphide. The sulphide solution containing the anti- mony is filtered off, the digestion repeated and the combined filtrates and washings are treated with an excess of hydrochloric acid. The pre- cipitated antimony sulphide is collected on a filter and the balance of the determination completed as described above. NICKEL The only nickel salt that has ever attained any importance in medi- cinal chemistry is the bromide which is employed as an antispasmodic. As it is of unusual occurrence it might be overlooked unless the label of the preparation indicated its presence. It is usually combined with codein. A determination of the halogen is the simplest method of estimating nickel bromide. The metal may be determined by precipitating as hydrox- ide with potassium or sodium hydroxide. A solution of the salt is treated with an excess of the alkali and heated for some time nearly to boiling. The supernatant liquid is decanted, the hydroxide boiled up three or four times with water, decanting each time, and then brought onto the filter and thoroughly washed. After drying, the precipitate is ignited in a porcelain crucible and weighed as nickelous oxide, MO. Instead of weighing as the oxide the latter may be reduced to the metal by ignition in a slow stream of hydrogen. The heat is applied gently at first and then more strongly until a constant weight is obtained. With some mixtures it will be better to separate the nickel first as sul- phide. A concentrated solution should be treated with ammonium chloride until nearly saturated, ammonia added until slightly alkaline, then acetic acid in slight excess. Ammonium or sodium hydroxide are then added, and the hydrogen sulphide passed through the boiling solution. If there is considerable nickel present and hence more than a small amount of acetic acid liberated, it will be necessary partially to neutralize during the process. Filter the sulphide, test the filtrate with a few drops of ammonium sulphide to determine whether the nickel has been completely thrown out, wash the precipitate with dilute hydrogen sulphide water, and dry. The precipitate is then transferred to a beaker, the filter inciner- ated in a porcelain crucible and the ash added to the beaker, aqua regia added, digested at a gentle heat until the sulphide is dissolved, and the undissolved sulphur appears yellow; the liquid is then diluted, filtered, and the nickel precipitated as hydroxide as described above. METALS AND THEIR COMPOUNDS 1003 If iron is present it may be removed before precipitating the nickel for its final determination, by adding ammonium chloride, and warming, adding ammonia in excess and digesting for several hours. Nickel will remain in solution. After filtering and washing, the ferric hydroxide should be dissolved in hydrochloric acid and precipitated again under the same conditions as before, adding the filtrate to that first obtained. The operation should be repeated a third time. The combined filtrates are then concentrated and the nickel determined as described. IRON Iron is used in medicine in the form of metallic or reduced iron; in the, ferrous state (ferrous carbonate in Blaud's mass and Vallet's mass, and ferrous iodide), in the ferric state (ferric chloride); and in complex combinations. In the latter the iron does not respond to the usual reactions until the compound has been subjected to the action of a reagent capable of breaking up the complex form. Solutions of ferric salts are used externally as styptics, and as astrin- gents in gargles, but the principal use of iron is for the treatment of anemia, chlorosis, and conditions where a tonic or alterative is desired. Iron salts will be encountered in several different types of pharmaceu- tical combinations, including pills, tablets, elixirs, wines, syrups, solu- tions, capsules, and gargles. The formulas are legion. The detection of iron presents no difficulties, and if present in a preparation, it will unquestionably be found during the course of the systematic analysis. The analyst may be called upon to determine the state in which the iron exists, as this feature may, in some cases, determine the efficacy of the medicine and also the claims set forth on the label. It is not enough to report that iron is present and its percentage amount given, the analyst should know whether it is in the ferrous or ferric state, and how much of each form exists as the preparation is administered. Vallet's mass consists of ferrous carbonate which has been washed free of sodium carbonate and preserved with a saccharin mixture. Blaud's mass prepared with potassium carbonate, contains all of the potassium sulphate produced by the reaction with ferrous sulphate. Ferrous car- bonate saccharated, prepared by precipitating the iron with sodium bicar- bonate, consists of the ferrous salt intimately mixed with sugar. Iron preparations often contain other metallic salts from which the metal must be separated in making a quantitative estimation, and phos- phates are sometimes present, thereby complicating the analysis, and, in some cases, rendering a quantitative determination difficult or impos- sible. The separation of iron from the metals of the arsenic and copper groups is of course easily effected, as these bodies are removable by hydrogen 1004 INORGANIC SECTION sulphide, in presence of dilute hydrochloric acid, leaving the iron still dissolved. Iron being precipitated by ammonia in presence of ammonium chloride, can be separated from the alkali metals and the alkaline earths unless phosphates are present, in which case the alkaline earths compli- cate matters by precipitating simultaneously. Of its own family, the only metal of any importance accompanying iron is manganese. With many preparations, especially syrups and elixirs, it is possible to determine iron in the same sample that has been used for determining the alkaloids. With pills and tablets the organic substances can be dis- solved out with alcohol, leaving the iron salts behind for subsequent treatment dependent on the results of the qualitative investigation. Ferric chloride is of course soluble in alcohol, but this salt is seldom found except in solution, though it is combined with antipyrin as ferropyrin. Assay of Ferrous Carbonate Saccharated. — Dissolve about 2 grams of saccharated ferrous carbonate, accurately weighed, in 15 mils of diluted sulphuric acid, and dilute the solution with distilled water to about 100 mils. Titrate immediately with N/10 potassium dichromate V. S., potas- sium ferricyanide T. S. being used as indicator. It shows not less than 15 per cent of FeCC>3. Each mil of N/10 potassium dichromate V. S. used corresponds to .011584 gram of FeCOs. Each gram of saccharated ferrous carbonate corresponds to not less than 13 mils of N/10 potassium dichromate V. S. Reduced Iron — Assay for Metallic Iron. — Introduce about 2.6 grams of iodin into a 100-mil glass-stoppered graduated flask, weigh accurately, add 6 mils water, 2 grams potassium iodide and .555 gram reduced iron. Stopper the flask, and after thoroughly mixing the contents by rotating, set aside for one hour. Then dilute the contents with distilled water and make the liquid measure exactly 100 mils when cool, mix well, draw off 25 mils of this solution and titrate with N/10 sodium thiosulphate. Divide the weight of the iodin taken by .02518, subtract from the quotient twice the number of mils of N/10 thiosulphate used; the remainder repre- sents the percentage of metallic iron present in reduced iron and this should not be less than 90 per cent. The percentage purity of the iodin should be accurately determined, and in place of the 2.6 grams above directed, its equivalent of pure 100 per cent iodin may be taken. Determination of Ferric Iron. — Ferric iron is easily determined by taking advantage of the reaction occurring in potassium iodide solution containing hydrochloric acid. The liberated iodin is titrated with N/10 sodium thiosulphate, 1 mil of which is equivalent to .00555 gram iron. A weighed amount of the salt or liquid to be tested is weighed into a glass- stoppered bottle of about 100-250 mils capacity, 2 mils of hydrochloric acid, a proper quantity of water and 1 to 2 grams potassium iodide. The METALS AND THEIR COMPOUNDS 1005 mixture is kept for one-half hour at 40° C, then cooled and the iodin titrated. U. S. P. PRODUCTS BY THE ABOVE METHOD Hydro- Potas- Product Sample used Water, mils chloric Acid, mils sium Iodide, grams Standard Ferric chloride 1 gram dry .555 gram 100 3 2 Not less than 22 mils Ferric citrate 15 2 1 Not less than 16 mils Ferric and ammonium citrate. . .555 gram 15 2 1 Not less than 16 mils Ferric and ammonium sulphate .555 gram 15 2 1 Not less than 11.5 mils Ferric and ammonium tartrate .555 gram 15 2 1 Not less than 13 mils Ferric and potassium tartrate. . .555 gram 15 2 1 Not less than 15 mils Ferric and quinin citrate (see assay following) .555 gram 3 1 Not less than 13.5 mils Ferric and strychnin citrate (see assay following) 1.11 4 1 Not less than 32 mils Ferric phosphate .555 10+40 2 1 Not less than 12 mils Ferric phosphate (soluble) .... .555 10+40 8 2 Not less than 10 mils Solution of ferric chloride 10 mils di- luted to 100 and 11.1 mils taken 10 2 1 Not less than 20 mils Solution of ferric sub-sulphate . 10 mils di- luted to 100 and 11.1 mils taken 10 > 1 Not less than 27. 15 mils Solution of ferric sulphate 1.11 15 2 1 Not less than 20 mils Colorimetric Estimation of Iron, J. S. Mayer. 1 — The originator of this method recommends it especially for assaying beef, iron, and wine, and other iron protein mixtures. Ten mils beef, iron, and wine are diluted with distilled water to 500 mils; 5 mils of this solution are evaporated and ignited in a platinum dish, 5 mils hydrochloric acid (1-1) added, the mixture boiled an instant, poured into a 100-mil Nessler tube, water added to 100 mils, 3 drops potassium permanganate (5-1000) added to oxidize the iron, and after a few minutes 10 mils of potassium thiocyanate (20-1000) added, the color produced being immediately compared with iron standards. Multiply the reading of the standard tube by 100 and the result will be milligrams of iron per 100 mils of sample. The iron standards are made up according to the method of D-. D. 1 J. Amer. Pharm. Assn., 1916, 5, 517. 1006 INORGANIC SECTION Jackson, by mixing definite quantities of two solutions, one containing potassium platinic chloride and the other cobaltous chloride. ASSAY OF IRON AND QUININ CITRATE Assay for Quinin. — Introduce 1.11 grams of the salt into a dish, and, with the aid of a gentle heat, dissolve it in 20 mils of water. Transfer the solution, together with the rinsings of the dish, to a separator, allow the liquid to become cold, then add 5 mils of ammonia water and 10 mils of chloroform, and shake the separator for one minute. Allow the liquids to separate, draw off the chloroformic layer, and shake the residuary liquid a second and a third time with portions of 10 mils each of chloro- form. Allow the combined chloroformic solutions to evaporate spon- taneously in a tared dish, and dry the residue at 100° C. to a constant weight. This residue should weigh not less than .1276 gram (correspond- ing to at least 11.5 per cent of dried quinin). Assay for Iron. — Heat the aqueous liquid, from which the quinin has been removed in the manner just described, on a water-bath, until the odor of chloroform and of ammonia have disappeared, allow it to cool, and dilute it with water to the volume of 50 mils. Transfer 25 mils of the liquid to a glass-stoppered flask having the capacity of about 100 mils, add 3 mils of hydrochloric acid and 1 gram of potassium iodide, and after securely closing the flask, allow the mixture to stand for half an hour at 40° C. After it has been allowed to cool, it should require not less than 13.5 mils of N/10 sodium thiosulphate to discharge the color of the liquid, starch being used as indicator (each mil of the N/10 sodium thiosulphate indicating 1 per cent of metallic iron), ASSAY OF IRON AND STRYCHNIN CITRATE Assay for Strychnin. — Dissolve 4.44 grams of the salt in a separator, in 15 mils of water, add 5 mils of ammonia water, 10 mils of chloroform, and shake the separator for one minute. Allow the liquids to separate, draw off the chloroformic layer, and shake the residuary liquid a second and a third time with portions of 10 mils each of chloroform. Allow the combined chloroformic liquids to evaporate spontaneously in a tared dish, and dry the reside at 100° C. to a constant weight. This residue should weigh not less than .04 (.0399) gram, nor more than .0444 gram (corresponding to not less than .9 nor more than 1 per cent of strychnin). Assay for Iron. — Heat the aqueous liquid, from which the strychnin has been removed in the manner just described, on a water-bath, until the odors of chloroform and of ammonia have disappeared, allow it to cool, and dilute it with water to the volume of 100 mils. Transfer 25 mils of the liquid to a glass-stoppered flask having the capacity of about METALS AND THEIR COMPOUNDS 1007 100 mils, add 4 mils of hydrochloric acid and 1 gram of potassium iodide, and after securely closing the flask, allow the mixture to stand for half an hour at 40° C. After it has been allowed to cool, it should require not less than 32 mils of N/10 sodium thiosulphate to discharge the color of the liquid, starch being used as indicator (each mil of N/10 sodium thiosulphate indicating one-half per cent of metallic iron). Total iron in a pharmaceutical mixture is determined by boiling the liquid or powdered solid material with rrydrochloric acid, adding a little nitric acid to oxidize any ferrous salt present, adding ammonium chloride, and excess of ammonium hydroxide and boiling until the ferric hydroxide separates. The solution is filtered and the precipitate washed with hot water, dried, ignited on the filter, and weighed as Fe203. If much organic matter is present it may be necessary to pass in hydro- gen sulphide after adding the ammonia and precipitate the iron as sulphide. The iron sulphide is collected on a filter, washed with water and dissolved in hot dilute hydrochloric acid. The clear liquid is boiled with the addi- tion of a little nitric acid, ammonium chloride added and the iron pre- cipitated with ammonium hydroxide, completing the determination as usual. Phosphates in solution simultaneously with alkaline earth metals complicate the determination. If these substances have been indicated by the qualitative tests, the ammonium hydroxide precipitation is con- ducted in the usual way, the well-washed precipitated dissolved in dilute sulphuric acid, heated, and reduced with metallic zinc. Sufficient sul- phuric acid is added to bring all of the zinc into solution, and the iron is then titrated immediately with permanganate. Most of the pills and tablets which are supposed to contain ferrous salts, will contain more or less ferric iron, and an estimation of the total iron does not indicate the quantity of the ferrous salt. For quantitative purposes the solution of the organic matter with alcohol may result in the oxidation of some of the ferrous compound unless the extraction is conducted in a closed flask. The estimation of ferrous iron is accom- plished in two waj s. 1. The finely ground substances are boiled with strong alcohol under a reflux condenser until the organic matter is dissolved. The super- natant liquid is decanted hot, the residue boiled up with a fresh portion of alcohol under the reflux, decanted again, and the procedure repeated as long as any organic matter dissolves. The flask is then fitted with a two-hole stopper containing an outlet tube which can be dipped into a beaker of recently boiled water, and an inlet tube, through which passes carbon dioxide (or the apparatus described below may be used). The substance in the flask is covered with hydrochloric acid, 1.2 sp. gr., pre- viously boiled to expel air, a current of carbon dioxide passed into the 1008 INORGANIC SECTION flask and the mixture boiled. When all traces of alcohol have been driven off and the iron salt dissolved, the outlet tube is dipped into the water, the carbon dioxide stream checked and about 25 mils of water allowed to run back into the flask. The stream of carbon dioxide is allowed to flow slowly and the flask rapidly cooled. The stopper is withdrawn and the solution poured into a large evaporating dish which contains an acid solution of zinc sulphate prepared by dissolving 3 grams zinc in 30 mils sulphuric acid 1 in 2, 1000 mils recently boiled and cooled water added, and the whole titrated with permanganate. If the insoluble material is dark colored and obscures the end reaction, the contents of the flask may be transferred to a graduated container of any convenient capacity, and made up to volume with recently boiled distilled water. After the insoluble material has settled, aliquots are pipetted off and titrated. 2. About 1 gram of the finely powdered substance is weighed into a flask and boiled with a small quantity of strong hydrochloric acid diluted with about half its volume of water, until the iron salt is dissolved, using an apparatus similar to that described above or as follows: The solution is transferred to a graduated flask of 100-mils capacity and made up to the mark with recently boiled distilled water; 25-mil METALS AND THEIR COMPOUNDS 1009 portions are then titrated with potassium bichromate. The end of the reaction is ascertained by means of a freshly prepared dilute solution of potassium ferricyanide used as an outside indicator. A number of drops of the reagent are placed upon a white plate or tile, and from time to time, during the addition of the bichromate, a drop of the solution is with- drawn on the end of a glass rod and brought in contact with one of the drops of indicator. When the reaction is complete no blue coloration is obtained. It is well to carry out a preliminary titration to determine approximately the amount of bichromate needed to complete the reaction. The total iron in the preparation can be determined in the hydro- chloric acid solution by transferring a 25-mil aliquot to a flask, heating to boiling and adding a clear freshly prepared solution of stannous chloride drop by drop, until the yellow color of the ferric chloride is just discharged. Any excess of stannous chloride is removed by adding a few drops of mercuric chloride. The iron is then titrated with bichromate. Determination of Ferrous Hypophosphite in a Solution of the Salt. — The solution as prepared always contains a certain amount of free phos- phoric acid. Weigh out the sample into a 250-mil Erlenmeyer flask, add 25 mils distilled water, 2 mils concentrated sulphuric acid, and heat to boiling. Run in N/10 permanganate gradually, until finally one drop produces a fugitive pink color. Then remove one drop of the solution on the end of a glass rod, place on a white glazed-porcelain plate and apply one drop of a very dilute solution of potassium ferricj^anide. If a blue color appears, it shows that the ferrous salt has not been entirely oxidized. Continue to add permanganate gradually until on testing one drop with the ferricyanide solution there is no blue color obtained. From the number of mils of permanganate employed the amount of ferrous hypo- phosphite, Fe(PH 2 02)2, is calculated. It is well to run a control experiment in the first place with a sample equal to that employed in the subsequent determination. The iron in organic products is determined b}' igniting the substance and dissaving the residue in nitric and hydrochloric acid. The liquid is diluted, filtered from any carbonaceous matter, and the iron determined as usual. This procedure should be used when working with prepara- tions of beef, iron, and wine, and whenever ammonium citrate occurs simultaneously with iron. Iron Peptonate and Manganese Preparations. — These combinations are popular as general tonics and as remedies for chlorosis and anemia. The solutions are dark-brown in color, Ferro-Mangan, Dieterich, and Pepto-Mangan being representative. The treatment of products of this class has been described in detail under Manganese. A distinction should be drawn between those compounds in which iron is in actual chemical combination with organic substances, and those 1010 INORGANIC SECTION in which it is actually in an inorganic form, but is prevented from respond- ing to its characteristic tests, on account of the presence of organic salts such as citrates or tartrates. ORGANIC IRON PREPARATIONS The term, " organic iron " is confined by modern usage to those organic compounds of iron which do not give the chemical tests of this metal until the structure of the molecule has been destroyed by reagents. Ferratin. — Sodium Ferrialbuminate Ferratin is the sodium salt of ferrialbiiminic acid, containing iron in the ferric state in organic combination, equivalent to 6 per cent metallic iron. Sodium ferrialbuminate occurs naturally in the organs of mammals, especially in the liver. Ferratin is prepared from egg albumin and chemically pure iron salts in the presence of alkalies. It is a light-brown, tasteless powder, having a faint odor. It is solu- ble in weak alkaline aqueous solutions, from which solutions it is pre- cipitated by hydrochloric acid. On dissolving .3 gram ferratin in 10 mils of water with the aid of a few drops of ammonia water, and then adding an equal volume of a 25 per cent potassium carbonate solution, no pre- cipitation occurs. Hemaboloids Hemaboloids is a liquid said to contain in each 100 mils iron com- bined with proteins, equivalent to .40 gram elementary iron, proteins and nucleoproteins (nitrogen X 6.25) 4.0 grams, bone marrow extract 5.0 grams, nuclein .04 gram, in a menstruum containing 17 per cent alcohol by volume. It is claimed that 75 per cent of the iron is in a stable organic combination with vegetable nucleoproteins and does not react with hema- toxylin, while the remaining 25 per cent is more loosely combined. Ovoferrin Ovoferrin is a solution containing 5 per cent of an artificial proteid- product in which iron is present in the so-called " organic " or " masked " form. Ovoferrin is prepared by modifying serum-albumin by electrolysis, producing a proteid which is classed by the manufacturers as a vitellin, and introducing ferric hydrate into this proteid by heating under pressure. The " vitellin " constituent of this preparation should not be confounded with the well-known vitellin of yolk of eggs. METALS AND THEIR COMPOUNDS 1011 The solution has a reddish-brown color, little odor, and a flat, slightly aromatic and alcoholic taste. The solution does not give a blue color on the addition of potassium ferrocyanide solution; a blue tint develops slowly if an equal volume of 5 per cent hydrochloric acid is added to the mixture; a deep-blue color develops at once if this mixture is boiled (difference from egg yolk). The solution is not precipitated by boiling, but gives precipitates with the alkalies, with which it is incompatible. It is also precipitated on half saturation with ammonium sulphate. It is not precipitated by acids. Proferrin A compound of iron and milk casein containing iron equivalent to about 10 per cent elementary iron and phosphorus equivalent to about .5 per cent elementary phosphorus. Prepared by treating an alkaline solution of casein with a solution of an iron salt and precipitating with acetic acid. It is a brown powder, almost odorless and tasteless, insolu- ble in water and dilute acids, slowly soluble in alkalies. If .5 gram is shaken with 10 mils distilled water, and the mixture filtered, the filtrate should give no precipitate on addition of ammonium hydroxide, and not more than a faint bluish tint on addition of a few drops of potassium ferrocyanide solution. If about 2 grams proferrin is digested for three hours at 40° C, with 40 mils of .2 per cent hydrochloric acid containing .006 gram pepsin, U. S. P., and the resulting mixture filtered, 5 mils of the filtrate diluted to 100 mils should produce not more than a faint-blue color on the addition of a drop of potassium ferrocyanide solution. Triferrin Triferrin is ferric paranucleinate; a compound of caseinparanucleinic acid with iron, containing 22 per cent of iron, 9 per cent of nitrogen and 2.5 per cent of phosphorus in neutral (organic) combination. It is prepared by digesting cow's milk-casein with pepsin and pre- cipitating the solution with a ferric salt. It is a tasteless powder, soluble in weak solution of sodium hydroxide, but insoluble in weak hydrochloric acid (.1 to .3 per cent). Hemogallol Hemogallol is an organic iron compound produced from blood by reduction of its hemoglobin by means of pyrogallol. Fresh defibrinated blood suitably diluted with water is mixed with an equal volume of saturated solution of pyrogallol, which causes the pre- 1012 INORGANIC SECTION cipitation of a voluminous precipitate which is separated, washed with water to remove pyrogallol, and finally with alcohol. It is a reddish-brown, almost tasteless powder, insoluble in water, alcohol, etc. It does not show the spectroscopic absorption bands of hemoglobin between D and E. Iron albuminate is a brown powder or scale, soluble in water. Albo- ferrin is an iron albumin compound. Iron alginate is a brown tasteless powder obtained by precipitating a solution of sodium alginate with ferric chloride. It is soluble in ammonia. Iron cacodylate is a grayish-yellow powder soluble in water. Iron glycerophosphate (ferric) is a yellow powder or scale, soluble with difficulty in alcohol and water. Ferratogen is a grayish-yellow substance obtained by growing yeast in a ferruginous medium. Ferrostyptin is a formaldehyde-iron preparation occurring in the form of yellow crystals, soluble in water, insoluble in cold alcohol and ether. Iron peptonate is prepared by treating an aqueous solution of beef peptone with a solution of iron oxychloride and precipitating with ammonia. In order to render the iron peptonate soluble in water, the precipitate is dissolved in ammonium citrate and the solution condensed to a thick jelly or completely dried in vacuo. CHROMIUM Chromium anhydride, so-called " Chromic Acid " CrCfe, is a caustic and astringent. It is used externally in the treatment of running sores and ulcers, to check hemmorhage, as an astringent for perspiring feet, for leucorrhea, and for foot and mouth disease. Potassium bichromate is used in gastric ulcers and syphilis, rand exter- nally for treating perspiring feet, tubercular elevations, warts, etc. It is combined with antimony sulphide, aconite, belladonna and Bryonia in tablets for bronchitis. Chromium is estimated by treating a weighed amount of the chromium anhydride-containing substance, with sodium hydroxide solution, acidi- fying strongly with acetic acid and precipitating hot with lead acetate. The lead chromate is then filtered into a tared Gooch, washed with hot water containing a little acetic acid, then with alcohol and ether, dried and weighed. Samples containing potassium bichromate are crushed, leached with hot water, filtered, the filtrate treated with sodium acetate and acetic acid and precipitated with lead acetate. If drug extracts are present, and tannins and soluble gums interfere METALS AND THEIR COMPOUNDS 1013 with a lead precipitate, the whole procedure must be changed. In this case the sample is digested with dilute hydrochloric acid, the liquid filtered into a beaker, neutralized with sodium hydroxide, acidified with hydro- chloric acid and subjected to the action of hydrogen sulphide until the color of the chromate has disappeared. The container is allowed to stand in a moderately warm place until the sulphur has settled, filtered into a porcelain or platinum dish and washed, the filtrate boiled to expel any residual hydrogen sulphide, cooled, ammonia added in slight excess, and the mixture exposed to a temperature approaching boiling until the liquid over the precipitate is perfectly colorless. The liquid is then decanted through a filter, the precipitate washed three times by decantation with hot water, finally brought onto the filter, washed, dried and ignited. The residue is O2O3, ALUMINUM Aluminum silicate is a component of antiphlogistic pastes which have attained considerable reputation. It provides the base, and is combined with glycerin, boric acid, menthol, thymol, eucalyptol, and ammonium iodide. The double sulphate of potassium and aluminum (Alum) is a power- ful astringent, used internally in painter's colic, in uterine injections and washes, and in styptic pencils. Uterine astringents and washes contain alum, zinc sulphate, morphin and Hydrastis, tannin and boric acid; and alum, boric acid, tannin, thymol, eucalyptol, salicylic acid, Helonias, Hyoscyamus, opium, and Hamamelis. Aluminum and ammonium sul- phate (ammonia alum) is used for similar purposes. Aluminum hydrate is employed in diarrhea and dyspepsia. It is sometimes combined with metallic aluminum and calcium carbonate. Aluminum acetate and chloride are used as disinfectants. Aluminum sulphocarbolate (Sozol) and aluminum naphthol-disulphonate (Alumnol) are used as substitutes for iodoform. They are both soluble in water and a solution of the latter fluoresces blue. To determine aluminum, five to ten tablets are ground or 10 to 25 mils of a solution evaporated to dryness, and ignited, if much organic matter is present, until the mass is completely charred. The residue is extracted with warm hydrochloric acid 1-1, fTtered into a beaker, made up to 150 mils, 25 mils ammonium chloride solution added and brought to a boil. Dilute ammonia is added in slight excess, the solution boiled for one minute, the precipitate allowed to settle, washed by decantation, filtering through a filter with a cotton plug. The precipitate is washed with 10 per cent ammonium nitrate solution and then burned wet, ignited to constant weight over a blast lamp and weighed as AI2O3. 1014 INORGANIC SECTION If zinc or calcium are present they can of course be determined in the filtrate. Phosphates and iron complicate this determination. The former are usually present in small quantity, if the tablets contain much drug extrac- tive, and iron often occurs as an impurity. If iron is present in quantity, the ignited residue should be dissolved in aqua regia, the acid evaporated, the residue dissolved in hydrochloric acid 1 to 1, the iron reduced by adding zinc and titrated with permanganate after pouring the solution into a solution of 3 grams of zinc dissolved in 30 mils sulphuric acid 1 to 2, and 1000 mils of recently boiled distilled water. Phosphoric acid can be estimated by dissolving the precipitate in aqua regia, evaporating, dissolving in dilute nitric acid, precipitating with ammonium molybdate and completing the determination as usual. MANGANESE Manganese does not functionate to a great extent in medicinal prod- ucts, but it will be overlooked many times unless the analyst is watch- ful. It is used principally in tonic mixtures, both liquid and pill, where it accompanies iron, and it will be found in the metallic hypophosphite preparations, and in the organic tonics of the Pepto-mangan type. Man- ganese iodide, lactophosphate, carbonate, and citrate have a limited use, but the principal form in which manganese is dispensed is the dioxide. The well known " pink pill " formulas consist of manganese dioxide, ferrous carbonate, gentian, strychnin, and licorice. Manganese iodide is combined with Leptandra, Juglans, Sanguinaria, and Hyoscyamus. Man- ganese dioxide has been reputed as an emmenagogue and should be looked for in emmenagogue pills. Determination of Manganese. — Twenty-five mils of a liquid prepa- ration is evaporated to dryness and gently charred, or ten to twenty pills are ground and charred. Fifteen mils of concentrated nitric acid are added to the residue, evaporated to dryness on the steam-bath, the car- bonaceous matter burned at a low heat, the addition of a further quantity of acid and repetition of the evaporation being carried out if necessary. After cooling, 10 mils of concentrated hydrochloric acid are added, and the dish covered and heated on the steam-bath until the iron has gone into solution. The acid is then evaporated to dryness, a further quantity added and evaporated to a syrupy consistency. One hundred mils of cold water are added, the solution filtered into a large beaker, thoroughly washing any precipitate left on the filter. The filtrate which should amount to about 200 mils, is treated with a strong solution of sodium carbonate until the precipitate formed dissolves but slowly. The car- bonate is then added carefully 2 to 3 mils at a time, with vigorous stirring, allowing several minutes to elapse between each addition to determine METALS AND THEIR COMPOUNDS 1015 whether the precipitate dissolves or not. When a decided precipitate remains, 2 drops of hydrochloric acid are added, well stirred, and the solution allowed to stand for several minutes. If it does not clear, a further 2 drops of acid are added, and this operation continued, until sufficient has been added to just dissolve the precipitate. Two grams of sodium acetate are dissolved in a little hot water and added to the solution, followed by 500 mils of boiling water, the beaker heated to boiling, and allowed to stand for ten minutes at the boiling temperature; the lamp is then removed and the precipitate allowed to settle. The supernatant liquid is decanted through a filter containing a plug of cotton, the precipitate brought onto the filter and washed with boiling water, the filtrate and washings trans- ferred to a porcelain evaporating dish and evaporated rapidly. When the precipitate has thoroughly drained, the filter containing it is trans- ferred to the beaker in which the precipitation was made, the iron dis- solved in 10 mils concentrated hydrochloric acid and a little water, filtered into a liter beaker, washing as usual and repeating the precipitation and filtration precisely as in the first case, adding the filtrate to the first one. The evaporation is continued until about 300 mils remain and the liquid filtered into a 500-mil beaker. Ten grams of sodium acetate are added, 3 to 5 drops of acetic acid and then ammonia until the liquid is decidedly alkaline. A few mils of bromin are added, the solution stirred, heated to boiling for five minutes, occasionally adding a little bromin water. The precipitate is allowed to settle, filtered, washed with hot water, dried and ignited to constant weight over a blast lamp. The ignited substance is Mn30 4 . Volumetric Method for Determining Manganese. — The sample is pre- pared in the same way as described above, treated with 15 mils of nitric acid, sp. gr. 1.2, and boiled until nitrous fumes ceased to be given off. One gram of red lead is added, 30 mils of hot water and the mixture boiled four to five minutes. The supernatant liquid is decanted into a beaker and the residue boiled with hot water containing 20 to 25 per cent of nitric acid. The boilings and decantations are continued as long as they show a decided color, and the united decantations are filtered through asbestos which has been ignited in oxygen gas. The filtered solution is then made up to a definite volume and aliquots titrated with sodium arsenite solution. The reagent is prepared and standardized as follows: .495 gram of sodium arsenite is dissolved in 300 mils water containing 2.5 gram sodium carbonate and diluted to 1 liter. It is run against N/100 permanganate by transferring a measured quantity of the latter to a flask, adding 50 mils water and 20 to 30 mils nitric acid 1.2 sp. gr. free from nitrous fumes, and titrating cold. 2Mn 2 07+5As 2 03 = 4MnO+5As 2 5 1016 INORGANIC SECTION PERMANGANATES Potassium permanganate is used as an antidote in poisoning by alka- loidal salts, as an antiseptic for wounds and running sores, as an injection in leucorrhea, etc., and to a limited extent in mouth washes. Zinc per- manganate is also used as an antiseptic. Solutions of permanganates are usually made up directly from the salt or from compressed tablets. The percentage of actual permanganate in the salt or tablet is deter- mined by dissolving a small quantity of the substance (.1 to .5 gram) in water, acidulating with 5 mils dilute sulphuric acid, warming to 60° C. and titrating with N/10 oxalic acid. One mil N/10 oxalic acid = .0040842 gram Zn(Mn0 4 ) 2 +6H 2 0. ZINC Zinc salts are employed as tonics and astringents. The oxide will be found in toilet and face powders combined with talc, and as an exsiccant to inflamed and excoriated surfaces. It is combined with quinin, strychnin, Capsicum, and arsenous acid in pills used for dipsomania; with anti- pyrin, belladonna and Castanea for whooping cough; with Hydrastin, belladonna, salicin, and pepsin for night sweats. Zinc bromide is employed in epilepsy and other spasmodic affections, combined with atropin, ergotin, lupulin, and Scutellaria. Zinc acetate will be found in astringent washes with lead acetate, berberin, and morphin. Zinc chloride is present in mouth washes and pyorrhea remedies, combined with betanaphthol, men- thol, and formaldehyde. Zinc sulphate is combined with phosphorus, lupulin, and Valeriana; with alum, morphin, and Hydrastis; with lead acetate, morphin, and hydrastin; with alum, boric acid, tannin, morphin, and Hydrastis. Zinc phosphide is present in aphrodisiac pills which contain the salt by itself, and in combination with one or more of the following: Nux Vomica, reduced iron, Cannabis sativa, Hyoscyamus and Damiana. Zinc valerianate is combined with phosphorus and mor- phin; with phosphorus and strychnin; with the valerianates of iron, sometimes with addition of sumbul, and gold, and sodium chloride; with iron ferrocyanide, quinin, and Valeriana. Zinc sulphocarbolate is employed as an antiseptic wash and gargle, and internally as an intestinal anti- septic, where it is often combined with aloin; with bismuth salicylate; with the sulphocarbolates of calcium and sodium; and with salol, bismuth subnitrate, calomel, and pancreatin (cholera infantum tablets) . Zinc per- manganate is used as an astringent and antiseptic in urethritis. Zinc stearate is often used as a substitute for the oxide in dusting powders combined with acetanilid, and as an astringent in gonorrhea. METALS AND THEIR COMPOUNDS 1017 Determination of Zinc. — Zinc can usually be determined in simple mixtures by dissolving out the zinc salt with hydrochloric acid, precipi- tating with sodium carbonate, and igniting the zinc carbonate to con- stant weight. In most medicinal preparations and in talcum powders, even when iron is absent as an essential ingredient, small quantities of this element occur as an impurity, hence it is a good rule to get rid of the iron and other substances which may be thrown out by ammonia in the presence of ammonium chloride, and then precipitate the zinc as sulphide (in the presence of acetic acid if manganese is present), niter off the sulphide, dissolve it in hydrochloric acid, and precipitate as carbonate. In the case of a powder .2 to .5 gram are used as a sample; of a tablet from 10 to 20; and of a liquid 10 to 25 mils are evaporated to dryness; if starch is present, the material is extracted with strong hydrochloric acid in the cold, but if absent it may be boiled with a moderately diluted acid, filtering into a beaker and washing thoroughly. If bismuth is present the acid solution is precipitated by hydrogen sulphide, the bismuth sul- phide filtered off, the filtrate boiled to expel the excess of hydrogen sul- phide, a few drops of nitric acid added to oxidize the iron, and the solution cooled, some ammonium chloride added, excess of ammonia and boiled until the iron is fully precipitated. After filtering off the iron, the warm filtrate in a flask is subjected to the action of hydrogen sulphide (if man- ganese is present excess of acetic acid must be added) until the zinc is completely precipitated, the flask is filled up to the neck with hydrogen sulphide water and set aside in a warm place for twelve to twenty-four hours. The zinc sulphide is collected on a filter and washed with hot water. The filter containing the zinc sulphide is transferred to a beaker, covered with an excess of hydrochloric acid 1 to 1, warmed until the hydro- gen sulphide is driven off, filtered into a capacious porcelain casserole, washing with hot water. The solution is heated nearly to boiling and sodium carbonate added drop by drop until the liquid has a strong alkaline reaction, boiled a few minutes, the precipitate allowed to subside, the supernatant liquid decanted through an ashless filter, the precipitate washed three times by decantation with hot water, finally transferred to the filter, washed with hot water, and dried. The dry zinc carbonate is then tapped into a porcelain crucible and ignited to constant weight. The filter is burned in a platinum cage and the ash dropped into a crucible, treated with a few drops of nitric acid, the acid evaporated and the residue ignited at a low red heat. The product is zinc oxide, ZnO, and represents the total zinc present in the product. When working with preparations containing zinc permanganate, the permanganate should be reduced by boiling the solution with alcohol before proceeding with the analysis. Practically all of the manganese 1018 INORGANIC SECTION will separate as oxide, but the manipulation should follow the directions given above for precipitating the zinc in presence of manganese. CERIUM Cerium oxalate, Ce2(C204)3*9H20, is employed in many forms of gastric disturbances. It is dispensed in pills and tablets either alone or in combination with bismuth subnitrate; with Nux Vomica, pepsin, creo- sote and cocain. The commercial salt is really a mixture of the oxalates of the so-called rare earths, the cerium predominating. On ignition, it is converted to cerium oxide, Ce02, which is permanent, and oxides of accompanying bases, and can be used as a means of estima- tion. It amounts to about 47 per cent of the weight of the oxalate. Cerium oxide, obtained by igniting the salt, when dissolved in concen- trated sulphuric acid is the cause of the development of a blue color chang- ing to purple and red on adding strychnin, and this test is of value in detect- ing the presence of cerium oxalate in admixtures. Cerium oxalate can be separated from bismuth subnitrate by boiling the sample with dilute hydrochloric acid in which both dissolve, and pre- cipitating the bismuth with hydrogen sulphide. The cerium can then be thrown out as hydroxide by adding excess of potassium hydroxide and boiling. The hydroxide is filtered off, washed with hot water, dried, and ignited. If cerium oxalate occurs in a preparation which contains no other metallic salts, it can be determined by direct ignition of the sample and weighing the oxide. STRONTIUM Strontium salts have a limited use in medicine. The bromide, iodide, and salicylate are recognized in the Pharmacopoeia. The peroxide is used in ointments and dusting powders. Strontium is determined, if in the form of a soluble salt, by direct pre- cipitation of a solution with ammonium carbonate in the presence of ammonia. If the salt is insoluble in water it is brought into solution with a minimum quantity of hydrochloric acid and precipitated as above. The container is allowed to stand for several hours in a warm place, filtered onto an ignited tared Gooch, washed with water containing a little ammonia, dried, and ignited at a low heat. . Strontium carbonate, SrC03, loses its CO2 gradually at an intense heat. If phosphates are present they must be removed before precipitating with ammonium carbonate. If ammonia in presence of ammonium chloride produces a precipitate, and this precipitate, is found to consist in part of phosphates, sufficient hydrochloric acid is added to dissolve the pre- METALS AND THEIR COMPOUNDS 1019 cipitate, and the solution is made nearly neutral by the addition of sodium carbonate. A mixture of sodium acetate 10 per cent and acetic acid is added and the solution boiled and filtered if necessary. Ferric chloride is added to the filtrate drop by drop until precipitation is complete, at which point the liquid will begin to assume a distinct reddish color, and the mixture gently boiled for a few minutes (whereby the ferric acetate is converted into insoluble basic acetate) and then filtered. The solu- tion now contains any zinc or manganese and the alkaline earths as chlor- ides and their separation and determination can follow the usual methods. If calcium occurs simultaneously with strontium, the latter may be separated by treating the ammoniacal solution with about fifty times the quantity of the substances as weighed, of ammonium sulphate, and either boiling for some time with renewal of the water that evaporates, adding sufficient ammonia to keep the solution faintly alkaline, or allow- ing the determination to stand at the ordinary temperature for twelve hours. The precipitate which consists of strontium sulphate and a little ammonium strontium sulphate, is filtered, washed with a concentrated solution of ammonium sulphate, till the washings remain clear on the addition of ammonium oxalate, cautiously ignited, moistened with a little dilute sulphuric acid, reignited, and weighed. The diluted filtrate is then precipitated with ammonium oxalate for the determination of calcium. CALCIUM Calcium salts are used in medicinal preparations both for therapeutic and mechanical effects. Calcium carbonate and sometimes the phos- phate are present in tooth powders, pastes, and face powders, and the same salts, and also calcium sulphate, will often appear in pills and tablets as diluents and coating material. Calcium peroxide is being used to some extent in tooth powders. Calcium sulphide and iodide are extensively employed. Calcium car- bonate and phosphate occur in saline and chalybeate tonic mixtures combined with the chlorides and carbonates of sodium and potassium, magnesium carbonate, reduced iron and ferrous carbonate mass. Anti- acid mixtures include calcium carbonate with magnesium carbonate and sodium chloride. Calcium hypophosphite is extensively employed in pill, tablet, and syrup form combined with the hypophosphites of sodium, potassium, manganese, iron, quinin, and strychnin, sometimes with guaiacol or creo- sote. Calcium hypophosphite will be found in tonic emulsions of cod- liver oil, and with petrolatum. Calcium phosphate occurs in the saline and chalybeate mixtures described above and in pills and syrups with the phosphates of potassium, magnesium, iron, quinin and strychnin and phosphoric acid. 1020 INORGANIC SECTION Calcium lactophosphate occurs in pills and syrups with the digestive ferments, and with the lactophosphates of iron, manganese, potassium, and sodium. Calcium bromide is a remedy for epilepsy and hysteria, and is combined with the bromides of the alkali metals and ammonia. Calcium glycerophosphate functionates as a nerve and general tonic, and is often found with alkali glycerophosphates and soluble casein. In order to estimate calcium, consideration must be taken of the pres- ence of any phosphates or heavy metals of the third group in the prepa- ration under examination. If phosphates are present, they must be removed by dissolving the sample in dilute hydrochloric acid and proceeding as described for the separation of phosphates under the discussion of stron- tium. Any zinc or manganese can then be removed from the filtrate by adding ammonium chloride, rendering ammoniacal, and precipitating with hydrogen sulphide. The filtrate and washings from this treatment are boiled ' until free of hydrogen sulphide. The ammonium chloride already added should be in sufficient amount to hold up any magnesium (if this be present) from being precipitated by ammonia. The process takes the following course depending on the presence or absence of mag- nesium. 1. If Magnesium is Absent. — Ammonia is added until the liquid has a decided odor of the reagent and the liquid is heated to boiling. A warm strong solution of ammonium oxalate, to which a little ammonia has been added, is introduced in slight excess, the mixture boiled for a few minutes and allowed to settle. The clear liquid is then decanted through a well- matted Gooch, without disturbing the precipitate. The latter is washed three or four times by decantation with boiling water, allowing it to settle completely each time. The precipitate is then brought onto the filter and washed with warm water until the filtrate is free from ammonium oxalate. A flask is then inserted under the stem of the Gooch, the pre- cipitate dissolved in a small quantity of warm hydrochloric acid, and the Gooch well washed with warm water. The solution is treated with a few mils of concentrated sulphuric acid, diluted to 250 mils with water, heated to 60 to 70° and the oxalic acid titrated with N/10 permanganate; 63 parts of oxalic acid are equivalent to 70 parts of calcium, or 1 mil N/10 KMn04 = .002 gram calcium. 2. If Magnesium is Present. — Ammonia is added in slight excess, followed by ammonium oxalate as long as a precipitate forms, then a further portion of the same reagent, about sufficient to convert the mag- nesium to oxalate (which remains in solution). The mixture is allowed to stand at the ordinary temperature for twelve hours, the supernatant liquid decanted as completely as possible, the precipitate washed once by decantation and the filtrate and washings set to one side, and the pre- METALS AND THEIR COMPOUNDS 1021 cipitate dissolved in hydrochloric acid, diluted with water, made ammonia- cal and precipitated with ammonium oxalate, the mixture allowed to stand as before, washed by decantation onto the filter previously used, and the washings continued until free of ammonium oxalate. The precipitate is then dissolved in HC1, H2SO4 added and titrated as above described. The first filtrate contains most of the magnesium, the second portion, acidified with hydrochloric acid, is evaporated to small volume and then added to the first portion. The clear solution is then treated with an excess of sodium phosphate and the mixture stirred, care being taken to avoid touching the sides of the beaker with the stirring rod. The beaker is then covered, allowed to stand twelve hours without warming. The precipitate is collected on an ashless filter, any particles adhering to the beaker being scraped off with a piece of filter paper, washed with a mix- ture of 3 parts water and 1 part ammonia, sp. g. .96, until free from chlor- ides. The filter and precipitate are dried and then ignited in a platinum crucible. If the magnesium pyrophosphate is dark, the crucible is cooled, the salt moistened with nitric acid, the excess of acid evaporated and reignited. Determination of Calcium in Presence of Phosphate and Absence of all Other Metallic Phosphates Except the Alkalies. — The sample is dis- solved in dilute hydrochloric acid, ammonia added until a precipitate begins to form, the precipitate dissolved by the addition of a drop of hydrochloric acid, ammonium oxalate is added in excess and finally sodium acetate, the treatment of the precipitated oxalate and remainder of the determination following the procedure directed in 1 above. MAGNESIUM Magnesium salts are used as laxatives, refrigerants, antiacids, and diuretics. Magnesium oxide (calcined magnesia) is used in certain forms of dyspepsia, sick headache, acid conditions of the stomach, etc. ; it is com- bined with rhubarb in tablets, and with charcoal, ginger and pepsin in lozenges. It often accompanies cascara extracts in pills, tablets, and capsules. Magnesium acetate is combined with rhubarb. Magnesium carbonate is combined with calcium carbonate and sodium chloride; and with the chlorides, sulphates, and carbonates of sodium and potassium, carbonate and phosphate of calcium, reduced iron and ferrous carbonate in saline and chalybeate tonic compounds. Magnesium phosphate is combined with the phosphates of potassium, calcium, iron, quinin, and strychnin, and phosphoric acid in tablets and syrups. Magnesium sulphate is combined with ferrous sulphate, quassia, and sulphuric acid. This salt is a component of many of the so-called efferves- cent citrate of magnesia preparations. Many of these products contain 1022 INORGANIC SECTION magnesium sulphate in an effervescent base of citric and tartaric acids, and sodium bicarbonate often with the addition of sodium and potassium tartrate. Magnesium citrate, the true salt, is used in effervescent com- bination. Magnesium oxide is sometimes used as an absorbant material for castor oil when it is desired to adminster the latter substance in a dis- guised form. The determination of magnesium when it occurs alone or in com- bination with the alkali metals, is effected by bringing the substance into solution with water or dilute hydrochloric acid if necessary, adding ammo- nium chloride followed by ammonia, which should produce no precipitate. Sodium phosphate is then added drop by drop with constant stirring until a considerable excess is present, a further quantity of ammonia added, the beaker covered and set aside for several hours. The liquid is filtered and the precipitate washed with dilute ammonia (3 to 1) until free from chloride, dried and ignited as Mg2P207. When phosphates are present or the mixture contains alkaline earth metals, the determination follows the directions given under calcium on page 1020. Mixtures containing sugar, plant extractive, or organic matter should be incinerated before attempting to separate the magnesium. The ash is dissolved in hydrochloric acid and the estimation continued as usual. If phosphates are present in considerable quantity it will be impossible to obtain a white ash, and extreme temperatures should be avoided. As soon as the char is obtained, the dish is cooled, the mass extracted with dilute hydrochloric acid, and the liquid filtered off, washing free from acid with distilled water. The filter and carbonaceous matter is then reignited, if necessary with the addition of a small quantity of ammonium nitrate. THE ALKALI METALS AND AMMONIUM Sodium Sodium salts will be encountered in a great variety of medicinal prepa- rations. The bicarbonate usually accompanies calomel, and is often combined with acetanilid, caffein, and the bromides in headache powders and tablets. It is one of the ingredients of soda mint tablets, lithia tab- lets, and in a partly converted form, furnishes the effervescing feature of the granular effervescent salts. Sodium bromide is an ingredient of a large number of headache mix- tures sold in the form of powders, tablets, and liquids. Sodium chloride is a component of nasal tablets and liquid prepara- METALS AND THEIR COMPOUNDS 1023 tions used as douches, where it is often combined with borax and other sodium salts. Sodium hypophosphite is sold for its tonic value, and occurs with other metallic hypophosphites, quinin, and cod-liver oil emulsions. The glycero- phosphate is used for .the same purpose. Sodiuin phosphate is an ingredient of inorganic laxative preparations " liver salts," and effervescent salts. Sodium salicylate is used in antirheumatic remedies, often in combina- tion with other alkali salicylates, and in migraine tablets with antipyretics, camphor monobromated, Hyoscyamus and Gelsemium. Sodium sulphocarbolate is used as an intestinal antiseptic. Sodium sulphite is an antiferment, and will occasionally be found in special combinations intended for certain forms of indigestion. More than one sodium salt is often present in a single preparation. The other alkalies are used simultaneously in many instances, and the analyst may be at a loss to determine the proper acid radicle to which to attribute the metal. Often his only conclusion can be that the prepa- ation contains the chlorides, sulphates, and phosphates of sodium, potas- sium, and hthium. If the importance of the analysis warrants, the quan- tities of the different radicles can be determined and the proper equilibrium determined by a study of the figures. If sodium occurs as the only alkali metal, the quantity of the combi- nation present is probably best figured from the determination of the acid radicle. Sodium Bicarbonate This salt when free from normal carbonate, gives no color with phenol- phthalein, but does react alkaline to methyl red and methyl orange, and can be titrated with acid against these indicators. The determination of sodium bicarbonate in admixture with acetanilid and other substances of like nature has been fully described in the section dealing with those bodies. POTASSIUM Potassium salts enter into the composition of remedies intended for a great variety of aihnents. Several of the potassium salts, such as the acetate, bicarbonate, bitar- trate, carbonate, and nitrate are reputed to possess diuretic properties, and one or the other usually is present in the common kidney pills and liquid mixtures for kidney diseases. Kidney pills also contain extract of buchu, juniper berries, Digitalis and Squill as therapeutic agents. Methylene blue is occasionally added, not only for its remedial value, but 1024 INORGANIC SECTION for the sensational effect on the consumer, who is led to believe by the advertising matter that the peculiar color imparted to the urine is an indication that the remedy is producing the desired effect. Potassium nitrate is present in liquid remedies. Potassium bicarbonate is used in pills for the relief of cystitis, and may be combined with boric acid, atropin, and the extracts of buchu, triticum, Hydrangea, cornsilk, and Viburnum prunifolium. It is also present in liquid remedies for stomach troubles with rhubarb, Hydrastis, and digestives. Potassium bichromate is a component of bronchitis pills and tablets, with aconite, belladonna, Bryonia, * and sulphurated antimony. It is used as a remedy for gastric ulcer. Potassium bitartrate, combined with sulphur, is a common house- hold remedy. Potassium bromide is used in sedative mixtures for nervous condi- tions. It is often combined with other bromides, with Hyoscyamus, Cannabis sativa, chloral, Grindelia, and Eriodictyon. Granular efferves- cent caffein and potassium bromide is a well-known preparation. Potassium carbonate and ferrous sulphate furnish the well-known Blaud pills. Potassium carbonate is dispensed with aloes, and with rhubarb and Hydrastis. It is one of the ingredients of saline and chaly- beate tonics, with carbonates of sodium, calcium, and magnesium, potas- sium sulphate, sodium and potassium chloride, calcium phosphate, reduced iron, and Vallet's mass. Potassium chlorate is a household remedy for sore throat and is found by itself and combined with ammonium chloride, borax, and cocain. Potassium hypophosphite is combined with other hypophosphites in tonics and remedies for nervous troubles both liquid and solid. w Potassium iodide is employed as a remedy for asthma, syphilis, scrof- Jf ula, dropsy, and rheumatism. Asthma mixtures will contain potassium iodide, bromides, arsenites, Lobelia, Euphorbia pilulifera, belladonna, opium. In syphilitic preparations mercuric chloride, arsenic, and ferrous iodides, opium and Nux Vomica may accompany potassium iodide. Rheu- matic formulas will include colchicin, digitalin, guaiac, Phytolacca, sali- cylic acid, Gelsemium, and Cimicifuga. The well-known " Sarsaparilla " and blood remedy type of preparations may contain potassium iodide, sarsaparilla, Phytolacca, Stillingia, triticum, Trifolium, Arctium lappa, Berberis aquifolium, Xanthoxylum, Bicucculla canadensis and Cascara amagra. Potassium nitrate is combined with extract of white pine bark, wild cherry, squill, senega, ipecac, Sanguinaria, opium and methyl salicylate in white-pine compound tablets. It is combined with Aconite, opium, and camphor in cold tablets. Potassium osmate is used to relieve night sweats of phthisis. METALS AND THEIR COMPOUNDS 1025 Potassium phosphate is used as an alterative and is combined with other phosphates in tablets and elixirs. Potassium and sodium tartrate (Rochelle salt) is the laxative ingredient of Seidlitz mixture. It is often combined with magnesium sulphate in granular effervescent salts, and in aperient pills and elixirs it functionates with senna, cascara, colocynth, aloes, Leptandra, and juglans. Potassium sulphate will be found in nasal tablets, saline and chaly- beate tonics, and in purgative mixtures. LITHIUM Lithium salts are used as diuretics and antirheumatics. The benzoate is combined with potassium bicarbonate and the chloride, phosphate, and bicarbonate of sodium; also with the salicylate and Hydrangea (Lithiated Hydrangea) . Lithium carbonate and benzoate are the Uthium salts present in " Lithia tablets," the other ingredients being citric acid, potassium bicar- bonate, and boric acid. Lithium carbonate is sometimes combined with sodium arsenate, and with nickel bromide, codein sulphate, ipecac, and oil of anise. Lithium citrate is usually produced by the action of citric acid on lithium carbonate, and the salt as an individual is seldom dispensed. Granular effervescent preparations of Hthium citrate contain lithium car- bonate in an effervescent base of citric or tartaric acid, sodium or potas- sium bicarbonate, sodium phosphate, magnesium sulphate and caffein, strontium and ammonium salicjdates are often included. Lithium salicylate is combined with other alkali salicylates, manaca, coichicin, Phytolacca, and Cimicifuga. Lithium bromide occurs with other bromides in some of the proprietary remedies for epilepsy and nervous affections. AMMONIUM Ammonia water is used as an ingredient of liniments, and the free gas is readily detected by holding a piece of moistened red litmus over the mouth of the bottle. Ammonia and ammonium carbonate are the essential ingredients of smelling salts. The compound of ammonium which is most extensively used in medi- cine is the chloride. In cough lozenges it is dispensed alone and in com- bination with potassium chlorate; with cubeb, licorice, and codein; in bronchial mixtures with licorice, Tolu, cubeb, Hyoscyamus, senega, and ipecac; with licorice, opium, benzoic acid, camphor, tartar emetic, and oil of anise (brown mixture); with cocain, cubeb, and licorice; with quinin, camphor, opium, belladonna, and aconite (Coryza); with tartar 1026 INORGANIC SECTION emetic, Sanguinaria, and morphin. Many liquid combinations recom- mended for coughs and bronchial troubles contain ammonium chloride, licorice, aromatic balsams, opium alkaloids, senega, and ipecac. Ammonium bromide has a limited use, and may be expected in the same class of combinations which contain the bromides of the alkali metals. Ammonium carbonate is employed as a cardiac stimulant in fevers, pneumonia, and bronchitis. It is combined with asafetida and opium; with squill, senega, and opium; and with ammonium bromide, squill, aconite, senega, grindelia, and guaiac. Ammonium salicylate will be found in rheumatism and headache mixtures, and ammonium valerianate is used in nervous and spasmodic disorders. ESTIMATION OF THE ALKALI METALS General Observations. — If the sample under consideration consists of a single alkali salt of an inorganic acid, the acid radicle may be deter- mined, and the quantity of the metal calculated therefrom. When the determination of the metals themselves is essential the following points should be observed : If the specimen consists of a nitrate or salt of an organic acid, it should be converted to sulphate by adding free sulphuric acid 1 to 1, evaporating and igniting. If the sample consists of a complex mixture of drug extractive, with salts of the alkali metals, and perhaps other metallic salts, the organic matter should be destroyed completely by one of the following methods: careful ignition; boiling with aqua regia; digestion with concentrated sulphuric acid in a Kjeldahl combustion flask; combustion with sulphuric and nitric acids. If the sample is to be charred, do not carry the com- bustion to a complete carbon-free ash. Heat until it is well carbonized, then cool, extract with hot dilute acid, filter, wash, reignite the filter and residual carbon, extract with acid, and repeat if necessary. If the sample contains no organic matter, nitrates, salts of organic acids, direct solution in water or dilute hydrochloric acid will usually suffice to get the desired elements in shape for subsequent manipulation. From this point, however the solution was effected, the analysis pro- ceeds in a systematic way, removing any heavy metals by the use of hydrogen sulphide, filtering and eliminating the alkaline earth metals by appropriate means. The solution is made up to some definite volume 100-250 c.c. and aliquots taken for the assay. In presence of phosphates (unless the only salt present is an alkali phosphate) acidulate with hydrochloric acid, add an excess of ferric METALS AND THEIR COMPOUNDS 1027 chloride followed by sufficient ammonia to neutralize the greater portion of the free acid, mix with ammonium acetate in not too large excess and boil. Filter from the precipitated ferric phosphate at boiling temperature and wash with boiling water containing ammonium acetate. The filtrate will then contain the alkali metal free from phosphate. Boric acid may be removed by mixing in a platinum dish the dry salt or a dry residue obtained by evaporating a liquid product with sufficient hydrofluoric acid (which leaves no residue on evaporation in a platinum dish), digesting, then adding concentrated sulphuric acid drop by drop, heating gently at first and then more strongly until the excess of sulphuric acid is completely expelled. The boric acid is expelled as fluoride of boron, BF3, and the residue contains the metals in the form of sulphates. Removal of Alkaline Earth Metals. — The solution rendered slightly acid with hydrochloric acid, is brought to boiling, a slight excess of ammo- nium hydroxide added, followed by ammonium carbonate and ammonium oxalate. After cooling the solution is filtered and the precipitate washed. Ammonium chloride, if present, tends to hold magnesium in solution. If magnesium is present and it has been necessary to remove heavy metals, and ammonium chloride has been formed or added, the solution should first be evaporated to dryness, and the residue ignited below a red heat until ammonium salts have been driven off. After cooling it is dissolved in water and the analysis continued according to the regular program. ESTIMATION OF POTASSIUM, SODIUM AND LITHIUM The solution of one or more of the alkali metals, freed from other metals as above described, is rendered slightly acid with hydrochloric acid and concentrated in a porcelain or platinum dish (in the case of bromides or iodides the use of platinum must be avoided). Sufficient sulphuric acid (1 to 1) to convert all of the metal to normal sulphate is added, the evaporation continued until no further diminution in volume occurs. The residue is then ignited, using great caution in the early stages of the process to prevent loss by decrepitation. The final product is the normal sulphate of the metal, and is to be weighed as such, and the metal calculated therefrom. It will sometimes happen that in analyzing samples which contain organic matter of certain kinds, a small amount of carbonaceous matter will persist throughout the entire assay, and yield a grayish or brownish residue after ignition. In such cases, the cooled residue should be treated with a small quantity of ammonium nitrate, and again carefully ignited. Separation of Potassium. — The ignited sulphates of the metals obtained as above are dissolved in hot water, using at least 20 mils for each decigram of potassium oxide present, a few drops of hydrochloric acid added, and 1028 INORGANIC SECTION platinum solution in excess (2.1 grams H 2 PtCl 6 to 10 mils). The solu- tion is evaporated on a water-bath to a thick paste, treated with 80 per cent alcohol, filtered onto a tared Gooch, washed thoroughly with 80 per- cent alcohol both by decantation and on the filter, continuing the washing after the filtrate is colorless. Wash five to six times with 10 mils ammo- nium chloride saturated with potassium platinic chloride solution, then with a further quantity of 80 per cent alcohol, dry at 100° for thirty minutes and weigh. * Separation of Lithium. — The ignited sulphates obtained as above described are dissolved in water, slightly acidified with hydrochloric acid, brought to boiling, and barium chloride added gradually, with constant stirring, until in excess. The sulphate is allowed to settle out, the solu- tion filtered off, the precipitate washed, the barium removed by ammo- nium sulphate, the filtrate evaporated, dried at 120°, and ignited below redness to remove ammonium salts. The residue is treated with a mix- ture of equal volumes absolute alcohol and anhydrous ether, digesting for at least twenty-four hours with occasional shaking and thoroughly dis- integrating the salts. The liquid is decanted through a covered filter and the resdue treated with several portions of the alcohol-ether mixture. The filtrate contains the lithium salt, and the metal is estimated by evapo- rating the solvent and converting to sulphate. DETERMINATION OF LITHIUM AS PHOSPHATE The sulphate residue is dissolved in water, treated with an excess of sodium phosphate, rendered alkaline with sodium hydroxide, and evapo- rated to dryness. The residue is treated with enough water to dissolve the soluble salts with the aid of gentle heat, an equal volume of ammonia water added, the mixture digested for twelve hours at a gentle heat, filtered onto a tared Gooch, and the precipitate washed with an equal volume of water and ammonia water. The filtrate and washings are evaporated to dryness, the residue treated as before, and if more lithium phosphate is obtained it is added to that on the filter, washing as before. The precipitate is finally washed with alcohol and dried at 100° to con- stant weight. The precipitated normal lithium phosphate has the formula 2L13PO4+H2O, and the water is completely expelled at 100°. DETERMINATION OF POTASSIUM BY PERCHLORIC ACID This method appeared in the Chemist Analyst, Dec. 1, 1918. The solution of the alkali metals prepared in the usual way is freed from sulphates by barium chloride, evaporated to dryness and heated until ammonium salts are driven off — below red heat so as not to volatilize the potassium chloride. The residue is dissolved in 20 mils hot water, METALS AND THEIR COMPOUNDS 1029 sufficient perchloric acid added to combine with all the bases present, evaporated without stirring, cooled, and the residue dissolved in hot water. More perchloric acid is added and the solution evaporated until the heavy white fumes of perchloric acid are given off. After cooling, the residue is treated with 25 mils strong alcohol containing .2 per cent HCIO4 (1 mil 60 per cent acid to 300 mils alcohol) breaking up residue with stirring rod. The liquid is decanted through a tared Gooch contain- ing a mat which has been washed with the above wash alcohol. Wash once again with the wash alcohol, decant and transfer the precipitate to the crucible. Wash several times with the wash alcohol, dry for an hour at 120-130°, cool and weigh as KC10 4 . The salt may be washed off the mat with hot water and the crucible used repeatedly, AMMONIUM Ammonia and ammonium salts will be found in a great variety of remedies. Solution of ammonia gas is used in the preparation of the U. S. P. spirit and aromatic spirit, and occurs in liniments. Ammonium chloride is an important constituent of throat tablets, cough mixtures, and antiseptic tablets. The bromide, carbonate, sali- cylate, and valerianate have important though probably less extended uses. Ammonium salts, notably the citrate, occur in tonic mixtures of the beef, iron, and wine, and cod-liver extract type. Assay of Spirit of Ammonia. — Two mils of the sample are carefully weighed in a stoppered weighing bottle, diluted with 50 mils distilled water and titrated with N/2 sulphuric acid, using litmus or methyl red as an indicator. Estimation of Free Ammonia in Liniments, etc. — The weighed sample is introduced into a boiling flask, diluted with water, and distilled into a measured volume of N/10 hydrochloric acid or N/2 sulphuric acid colored with methyl red. The collecting flask should be watched, and if the color changes to yellow, a further measured quantity of acid is added. The free ammonia will come over during the first fifteen minutes of the distilla- tion. The excess of acid is titrated with standard alkali. The distilling flask of the Kjeldahl apparatus furnishes the most satis- factory receptacle for conducting this determination. Ammonium Salts alone or in Admixture with Other Inorganic Compounds or with Non-nitrogenous Organic Substances. — The weighed sample is introduced into a boiling flask, diluted with water, treated with an excess 1030 INORGANIC SECTION of concentrated sodium hydroxide and distilled into standard acid as directed above. Ammonium Salts in Presence of Nitrogenous Organic Substances. — This determination is applicable to preparations of beef, iron, and wine and cod-liver extracts. The weighed sample is introduced into a boiling flask, diluted with water, magnesium oxide added, and distilled into standard acid. Estimation of Ammonium Chloride in Antiseptic Tablets (Chapin). — Into each of two 150-mil Erlenmeyer flasks pipette 5 mils of the tablet solution previously prepared for the estimation of mercuric chloride (5 tablets per 100 mils) and add to each flask 2 mils of a 20 per cent solution of potassium iodide. Dilute one volume of 37 per cent formaldehyde solution with 3 volumes of water, measure 20 mils of the mixture into a small flask, add .5 mil of phenolphthalein indicator solution, neutralize with N/10 barium or caustic alkali, then flow the solution over the sides of one of the flasks, A, con- taining tablet solution -and mix well. To the other flask, B, containing tablet solution add about 65 mils water. Now add to flask A 25 mils water and titrate with N/10 barium or caustic alkali free from carbon dioxide until, by using flask B as a standard for comparison, a color change is perceptible (titration A). Add methyl red to flask B and titrate with either N/10 acid or alkali as needed (titration B). To titration A add titration B if performed with acid, or subtracted if performed with alkali. The resulting figure multiplied by the factor .0214 for strictly N/10 alkali will give the average weight of ammonium chloride per tablet. TABLES ATOMIC WEIGHTS Adopted by the International Committee on Atomic Weights (1915) Oxygen = 16 Name Aluminum. Antimony . Argon Arsenic. . . Barium. . . Bismuth. . . Boron Bromin Cadmium . Caesium. . . Calcium. . Carbon. . . . Cerium Chlorine. . . Chromium . Cobalt Columbium Copper. . . . Dysprosium Erbium. . . . Europium . . Fluorine. . . Gadolinium Gallium Germanium Glucinum. . Gold Helium. . . . Holmium. . Hydrogen . . Indium. . . . Iodin Iridium . . . . Iron Krypton. . . Lanthanum Lead Lithium. . . Lutecium. . Magnesium . Manganese . Symbol Atomic Weight Al 27.1 Sb 120.2 A 39.88 As 74.96 Ba 137.37 Bi 208.0 B 11.0 Br 79.92 Cd 112.40 Cs 132.81 Ca 40.07 C 12.00 Ce 140.25 CI 35.46 Cr 52.0 Co 58.97 Cb 93.5 Cu 63.57 Dy 162.5 Er 167.7 Eu 152.0 F 19.0 Gd 157.3 Ga 69.9 Ge 72.5 Gl 9.1 Au 197.2 He 3.99 Ho 163.5 H 1.008 In 114.8 I 126.92 Ir 193.1 Fe 55.84 Kr 82.92 La 139.0 Pb 207.10 Li 6.94 Lu 174.0 Mg 24.32 Mn 54.93 Name Symbol Mercury Molybdenum Neodymium Neon Nickel Niton (radium emanation) Nitrogen Osmium Oxygen Palladium Phosphorus Platinum Potassium Praseodymium Radium Rhodium Rubidium Samarium Scandium Selenium Silicon Silver Sodium Strontium Sulphur Tantalum Tellurium Terbium Thallium Thorium Thulium Tin Titanium Tungsten Uranium Vanadium Xenon Ytterbium (NeoytterbiumJ Yttrium Zinc Zirconium Hg Mo Nd Ne Ni Nt N Os O Pd P Pt K Pr Ra Rh Ru Sa Sc Se Si Ag Na Sr S Ta Te Tb Tl Th Tm Sn Ti W U V Xe YT) Y T t Zn Zr Atomic Weight 200.6 96.0 144.3 20.2 58.68 222.4 14.01 190.9 16.00 106.7 31.04 195.2 39.10 140.6 226.4 102.9 101.7 150.4 44.1 79.2 28.3 107.88 23.00 87.63 32.07 181.5 127.5 159.2 204.0 232.4 168.5 119.0 48.1 184.0 238.5 51.0 130.2 172.0 89.0 65.37 90.6 1033 1034 TABLES STANDARD SOLUTIONS Standard Sulphuric Acid, Standard Hydrochloric Acid, Standard Oxalic Acid Equivalents per 1 mil of standard Acid (To find the equivalent of any other normality, point off the proper decimal place or divide by the proper factor) N Acid, gram equiv. N/2 Acid, gram, equiv. N/50 Acid, gram equiv. Hydrochloric Acid, HC1 Sulphuric Acid, H 2 S0 4 Oxalic Acid, H 2 C 2 04+2H 2 Aconite. Ether soluble alkaloids Aconitin, C 34 H 47 0nN Ammonia, NH 3 Ammonium Acetate, NH 4 C 2 H 3 2 Ammonium Carbonate, (NH 4 ) 2 C0 3 Ammonium Carbonate, U. S. P., NH 4 HC0 3 -NH 4 NH 2 C0 2 Atropin, Ci 7 H 13 3 N Barium Hydroxide, Ba(OH) 2 +8H 2 Benzaldehyde, C 7 H 6 Brucin, C 23 H 26 4 N 2 Calcium Carbonate, CaC0 3 Calcium Hydroxide, Ca(OH) 2 Calcium Lactate, Ca(C 3 H 5 0) 3 . Calcium Oxide, CaO Cephaelin, d 4 Hi 9 2 N Chelerythrin, C 2 iH 17 4 N Cinchona. Combined alkaloids Cinchonidin, Ci 9 H 22 ON 2 Cinchonin, Ci 9 H 22 ON 2 Cinnamic Aldehyde, C 9 H 8 Citral, Ci H 16 O ' Cocain, Ci 7 H 2 i0 4 N Codein, C 18 H 21 3 N Codein, C ]8 H 21 3 N+H 2 Coniin, C 8 Hi 7 N Emetin, Ci 5 H 21 2 N Gelsemium Alkaloids Hydrastin, C 21 H 21 6 N Ipecac. Combined alkaloids Lead, Pb Lead Acetate, Pb(C 2 H 3 2 ) 2 Lead Acetate, Pb(C 2 H 3 2 ) 2 +3H 2 Lead Subacetate, Pb 2 0(C 2 H 3 2 ) 2 Lead Oxide, PbO Lead Peroxide, Pb0 2 Lithium Carbonate, Li 2 C0 3 Lithium Citrate, Li 3 C 6 H 5 7 Lithium Citrate, Li 3 C 6 H 5 7 +4H 2 0.03647 0.049045 0.063025 0.645 0.64539 0.01703 0.07707 0.04804 0.052373 0.28919 0.15776 0.39423 0.050035 0.037045 0.028035 0.23316 0.29420 0.29420 0.30318 0.29918 0.31719 0.12715 0.24718 0.408 0.38318 0.240 0.10355 0.16257 0.18960 0.13706 0.11155 0.11955 0.03694 0.034977 0.04699 0.018235 0.024523 0.031512 0.008515 0.0530 0.05454 0.033015 0.076 0.0007294 0.0009809 0.001205 0.012907 0.0057838 . 006943 0.0061841 0.005884 0.005884 0.0060636 0.002543 0.0076636 0.0048034 TABLES STANDARD SOLUTIONS— Continued 1035 N Acid, gram equiv. N/2 Acid, gram equiv. N/50 Acid, gram equiv. Lithium Salicylate, LiC 7 H 5 3 Magnesium Carbonate, (MgC0 3 ) 4 Mg(OH) 2 -f 5H 2 Magnesium Hydroxide, Mg(OH) 2 Magnesium Oxide, MgO Manganese Dioxide, Mn0 2 Morphin, C 17 H 19 3 N Morphin, C 17 H 19 3 N+H 2 Mydriatic Alkaloids combined Nitrogen, N Nux Vomica Alkaloids combined Physostigmin, d 5 H 2 i0 2 N 3 Pilocarpin, CuHi 6 2 N 2 Pomegranate Bark Alkaloids Potassium and Sodium Tartrate, KNaC 4 H 4 6 +4H 2 Potassium and Sodium Tartrate, Anhydrous Potassium Acetate, KC 2 H 3 2 Potassium Bicarbonate, KHC0 3 Potassium Bitartrate, KHC 4 H 4 06 Potassium Carbonate, K 2 C0 3 Potassium Citrate, K 3 C 6 H 5 7 +H 2 Potassium Citrate, Anhydrous Potassium Hydroxide, KOH Potassium Permanganate, KMn0 4 Quinin, C 20 H 24 O 2 N 2 Sabadilla Alkaloids Sanguinaria Alkaloids Sodium Acetate, NaC 2 H 3 2 +3H 2 Sodium Acetate, Anhydrous Sodium Benzoate, NaC 7 H 5 2 Sodium Bicarbonate, NaHC0 3 Sodium Biborate, Na-2B 4 O7+10H 2 O Sodium Biborate, Anhydrous Sodium Cacodylate, Na(CH 3 ) 2 As0 2 Sodium Carbonate, Na 2 C0 3 +H 2 Sodium Carbonate, Anhydrous Sodium Citrate, Na 3 C 6 H 5 7 +2H 2 Sodium Citrate, Anhydrous Sodium Glycerophosphate, NaoC 3 H 7 P0 6 Sodium Hydroxide, NaOH Sodium Salicylate, NaC 7 H 5 3 Sodium Tartrate, Na 2 C 4 H 4 6 +2H 2 Strontium Salicylate, Sr(C 7 H 5 3 ) 2 +2H 2 Strontium Salicylate, Anhydrous Strychnin, C 2 iH 22 2 Zinc Oxide, ZnO Zinc Permanganate, Zn(Mn0 4 ) 2 +6H 2 0.14398 0.04857 0.02016 0.043465 0.28516 0.30318 0.2092 0.014 0.364 0.27520 0.20815 0.147 0.14110 0.09812 0.10011 0.18814 0.06910 0.10812 0.05611 0.031606 0.32421 0.5984 0.35 0.13607 0.08401 0.19108 0.101 0.1600 0.06201 0.0530 0.04001 0.16004 0.33420 0.040685 0.040842 0.0148 0.07055 0.052533 0.04906 0.050055 0.09407 0.03455 0.05406 0.051057 0.028055 0.068035 0.04101 0.07202 0.042005 0.031005 0.02650 0.04901 0.04301 . 10805 0.020005 0.08002 0.057515 0.099435 0.9043 0.0057032 0.0060636 0.005504 0.004163 0037628 0.0062842 0.006684 1036 TABLES STANDARD SOLUTIONS Standard Potassium Hydroxide, Standard Sodium Hydroxide, Standard Alcoholic Alkali Equivalent per 1 mil of Standard Alkali N Alkali, gram equiv. N/2Alkali, gram equiv. N 50 Alkali, gram equiv. Potassium Hydroxide, KOH Sodium Hydroxide, NaOH Acetic Acid, HC 2 H 3 2 Acetic Acid Anhydride, (CH 3 CO) 2 Ammonia, NH 3 Ammonium Chloride, NH 4 C1 Betaeucain Hydrochloride, C 15 H 2 i0 2 N • HC1 Boric Acid, H 3 B0 4 Borneol, Ci Hi 8 O Bornyl Acetate, Ci H 17 C 2 H 3 O 2 Chloral Hydrate, C 2 H0C1 3 +H 2 Carvone, CioH x4 Camphor, Ci H 16 O Citric Acid, H 3 C 6 H 5 7 +H 2 Formaldehyde, CH 2 Hydriodic Acid, HI Hydrobromic Acid, HBr Hydrochloric Acid, HC1 Hypophosphorous Acid, HPH 2 2 Lactic Acid, HC 3 H 5 3 Menthol, C 10 H 20 O Menthyl Acetate, C 1C H 19 C 2 H 3 Methyl Salicylate, CH 3 C 7 H 5 Nitric Acid, HN0 3 Oxalic Acid, H 2 C 2 4 +2H 2 Paraformaldehyde, (CH 2 0) 3 Phosphoric Acid, H 3 P0 4 . To form K 2 HP0 4 with Phenolphthalein Potassium Bitartrate, KHC 4 H 4 6 Santalol, Ci 5 H 26 Sodium Bitartrate, NaHC 4 H 4 6 +H 2 0. Salicylic Acid, C 7 H 7 3 Sulphuric Acid, H 2 S0 4 Sulphur Trioxide, S0 3 Tartaric Acid, H 2 C 4 H 4 6 Trichloracetic Acid, HC 2 2 C1 3 0.05611 0.04001 0.06003 0.05102 0.01703 0.05350 0.28365 0.06202 0.1654 0.15 0.1509 0.07003 0.03002 0.12793 0.08093 0.03647 0.06606 0.09005 0.06302 0.063025 0.03002 0.04903 0.18814 0.1901 0.138 0.049045 0.040035 0.07503 . 16339 0.02806 0.020005 0.03002 0.03101 0.07707 0.09808 0.03502 0.06397 0.04047 0.01824 0.03303 0.04503 0.07808 0.09909 0.07603 0.03151 0.03153 0.02452 0.09407 0.111105 0.09503 0.024523 0.02002 0.03751 0.08170 0.0011222 0.0008002 0.0009809 TABLES 1037 FEHLING'S SOLUTION Equivalent per 1 Mil of Standard Solution N Solution, gram, equiv. Copper Sulphate, CuS0 4 +5H 2 Copper Tartrate, CuC 4 H 4 6 +3H 2 Cane Sugar (Sucrose), C12H22O11 (after inversion) Glucose, Anhydrous, C 6 Hi 2 6 Lactose, Anhydrous, Ci 2 H 22 0ii 0.03466 0.03688 0.00475 0.005 0.00678 BARIUM HYDROXIDE Equivalent per 1 Mil of Standard Solution N Solution, gram, equiv. Barium Hydroxide, Ba(OH) 2 +8H 2 Ammonium Benzoate, NH4C7H5O1! . . Ammonium Salicylate, NH4C7H5O3 . Benzoic Acid, C 7 H 6 2 Hydrochloric Acid, HC1 Salicylic Acid, C 7 H 6 3 Sulphuric Acid, H 2 S0 4 0.15776 0.13908 0.15508 0.12205 0.03647 0.13805 0.049045 BROMIN. (KOPPESCHAAR'S SOLUTION) Usually used as N/10 Equivalent per 1 Mil of Standard Solution N Solution, gram equiv. Bromin, Br Carbolic Acid, C 5 H 6 OH Orcin, C 7 H 6 (OH) 2 Resorcinol, C 6 H 4 (OH) 2 Sodiumphenolsulphonate, NaC 6 H 5 4 S +2H>0 Sodiumphenolsulphonate, Anhydrous 0.07992 0.01568 0.02068 0.01834 0.058035 0.04903 1038 TABLES IODIN Usually employed as N/10 Equivalent per 1 Mil of Standard Solution N Solution, gram equiv. Iodin, I Acetone, (CH 3 ) 2 CO Antimony Trioxide, Sb 2 3 Antimony and Potassium Tartrate, K(SbO)C4H40 6 +2H 2 Arsenic, As (in arsenous compounds) Arsenic Iodide, Asl 3 Arsenic Trioxide, As 2 3 Calcium Sulphide, CaS Formaldehyde, HCHO Iron, Fe Hexamethylenetetramine, (CH 2 )6N 4 Mercurous Chloride, HgCl Mercurous Iodide, Hgl Mercury, Hg (in mercurous compounds) Methyl Salicylate, CH 3 C 7 H 5 3 Potassium Sulphite, K 2 S0 3 +2H0 2 Sodium Bisulphite, NaHS0 3 . Sodium Sulphite, Na 2 S0 3 Sodium Thiosulphate, Na 2 S 2 3 +5H 2 Sodium Thiosulphate, Anhydrous Sulphur Dioxide, S0 2 0.12692 0.009675 0.072 0.16617 0.03748 0.22786 0.04948 0.03607 0.015 0.2792 0.01167 0.23606 0.32752 0.2006 0.02535 0.09715 0.05204 0.06304 0.24822 0.15814 0.032035 POTASSIUM DICHROMATE Equivalent per 1 Mil of Standard Solution N Solution, gram equiv. Potassium Dichromate, K 2 Cr 2 7 Glycerin, C 3 H 6 (OH) 3 Ferrous Carbonate, FeC0 3 Ferrous Sulphate, FeS0 4 +7H 2 Ferrous Sulphate, Anhydrous Iron, Fe (in Ferrous Compounds) Lactic Acid, HC 3 H 5 3 Sodium Thiosulphate, Na 2 S 2 3 +5H 2 0.049033 0.06549 0.11584 0.27802 0.15191 0.05584 0.02254 0.24822 TABLES 1039 POTASSIUM PERMANGANATE Usually employed as N/10 Equivalent per 1 Mil of Standard Solution Potassium Permanganate, KMn0 4 Calcium Dioxide, Ca0 2 Calcium Oxide CaO, (as oxalate) . Ferrous Carbonate, FeC0 3 Ferric Oxide, FesOs Ferrous Oxide, FeO Ferrous Sulphate, FeS0 4 +7H_0. . Ferrous Sulphate, Anhydrous .... Glycerin, C 3 H 5 (OH) 3 Hydrogen Dioxide, H 2 2 Iron in ferrous compounds, Fe . . . Magnesium Dioxide, Mg0 2 Oxalic Acid, H 2 C 2 4 +2H 2 Oxygen, Potassium Chlorate, KC10 3 Sodium Dioxide, Na 2 2 Sodium Chlorate, NaC10 3 Sodium Nitrite, NaN0 2 Sodium Oxalate, Na^C^ Strontium Dioxide, Sr0 2 Zinc Dioxide, Zn0 2 N Solution, gram equiv. 0.031606 0.036 0.28035 0.11584 0.07985 0.07184 0.27802 0.15191 0.046 0.017008 0.05584 0.02 0.063025 0.008 0.020427 0.03786 0.017743 0.034505 0.067 0.061 0.048 POTASSIUM SULPHOCYANATE Equivalent per 1 Mil of Standard Solution N Solution, gram equiv. Potassium Sulphocyanate, KSCN Mercuric Iodide, Hgl 2 Mercuric Nitrate, Hg(N0 3 ) 2 Mercuric Oxide, HgO Mercury, Hg Silver, Ag Silver Nitrate, AgN0 3 Silver Oxide, Ag 2 0.09718 0.22722 . 16231 0.1083 0.1003 . 10788 0.16989 0.11588 1040 TABLES SILVER NITRATE Usually employed as N/10 Equivalent per 1 Mil of Standard Solution N Solution, gram equiv. Silver Nitrate, AgN0 3 AUyl Iso-thiocyanate, C3H5SCN Ammonium Bromide, NHJBr Ammonium Chloride, NH 4 C1 Ammonium Iodide, NHJ Arsenous Iodide, Asl 3 Bromin, Br Calcium Bromide, CaBr 2 +2H 2 Calcium Bromide, Anhydrous Calcium Chloride, CaCl 2 +2H 2 Calcium Chloride Anhydrous Calcium Hypophosphite, Ca(PH 2 2 ) 2 Chlorine, CI Ferrous Bromide, FeBr 2 Ferrous Iodide, Fel 2 Hydriodic Acid, HI Hydrobromic Acid, HBr Hydrochloric Acid, HC1 Hydrocyanic Acid, HCN (to first formation of precipitate) . Hydrocyanic Acid, (with potassium chromate as indicator) . Iodin, I Lithium Bromide, LiBr Lithium Chloride, LiCl Phosphoric Acid, H3PO4 Potassium Bromide, KBr Potassium Chloride, KC1 Potassium Cyanide, KCN (to first formation of precipitate) Potassium Hypophosphite, KPH 2 2 Potassium Iodide, KI Potassium Nitrate, KNO3 > Potassium Sulphocyanate, KSCN Sodium Bromide, NaBr Sodium Chloride, NaCl Sodium Cyanide, NaCN (to first formation of precipitate) . Sodium Hypophosphite, NaPH 2 2 +H 2 Sodium Iodide, Nal Sodium Nitrate, NaN0 5 Sodium Phosphate, Na 2 HP0 4 +12H 2 Sodium Phosphate, Anhydrous Strontium Bromide, SrBr 2 +6H 2 r Strontium Chloride, SrCl 2 +6H 2 Strontium Iodide, SrI 2 +6H 2 Zinc Chloride, ZnCl 2 16989 04956 09796 05350 14496 15191 07992 11797 099955 073511 0555 02836 03546 10784 15484 12793 08093 03647 05404 02702 12692 08686 0424 032687 11902 07456 13022 03472 16602 10111 09718 10292 05846 09802 035357 14992 08501 11941 04735 17779 13332 22479 068145 TABLES 1041 SODIUM CHLORIDE Equivalent per 1 Mil of Standard Solution Sodium Chloride NaCl. Silver, Ag Silver Nitrate, AgN0 3 . N Solution, gram equiv. . 05846 0.10788 0.16989 Silver Oxide, A&O 0.11588 SODIUM THIOSULPHATE Usually employed as N/10 solution Equivalent per 1 Mil of Standard Solution X Solution, gram equiv. Sodium Thiosulphate, Xa 2 S 2 3 +5H 2 0.24822 Bromin, Br | .07992 Chlorine, CI 0.03546 Chromium Trioxide, Cr0 3 : 0.03333 Copper Sulphate, CuS0 4 +5H 2 j 0.24972 Copper Sulphate, Anhydrous ! . 15964 Iodin, I | 0. 12692 Iodin, I (from thyroid glands) Iodin, I (thymol iodide) 0.02115 Iron, Fe (in ferric salts) . 05584 Lead Peroxide, Pb0 2 0. 1195 Mercuric Chloride, HgCl 2 0.271 Potassium Bromate, KBr0 3 0.027837 Potassium Dichromate, L>Cr 2 7 0.049033 Sodium Arsenate, Na 2 HAs0 4 +7H,0 . 15604 Sodium Arsenate, Anhydrous . 092985 Salicylic Acid, C 7 H 6 3 0.06885 Thymol, CioH 14 0.075056 X 2 Solution, gram equiv. 0.12411 0.06346 0.01058 1042 TABLES REAGENTS Test Solution and Indicators The solutions have been made to conform as nearly as practicable with those given in the Pharmacopoeia, and in most cases directions for preparation are given on the basis of 100-mil quantities. Whenever the word " water " is used it is understood to mean " distilled water." Acid, Acetic Glacial. 35 mils glacial acid with 65 mils water. 6 mils glacial with 94 mils water. Acid, Acetic, 36 per cent. Acid, Acetic Dilute, 10 per cent. Acid, Hydrochloric Cone. Acid, Hydrochloric Dilute, 10 per cent. Acid, Nitric Cone. Acid, Nitric Dilute, 10 per cent. Acid, Sulphuric Cone. Acid, Sulphuric Dilute, 10 per cent. Alcohol, 95 per cent. Ammonia Water (stronger) 28 per cent. Ammonia Water Dilute, 10 per cent. Ammonium Carbonate. Ammonium Molybdate. Ammonium Oxalate. Ammonium Sulphate. Ammonium Sulphide. Ammonium Validate. (Mandelin's Reagent.) Azolitmin. Barium Chloride. Barium Hydroxide. Bromin Water. Cadmium and Potassium Iodide. Cadmium Chloride. Calcium Chloride. Calcium Hydroxide. 30 mils hydrochloric acid cone, with 70 mils water. 11 mils nitric acid cone, with 89 mils water. 7 mils sulphuric acid cone, with 93 mils water. 36 mils stronger ammonia water with 64 mils water. 20 grams ammonium carbonate U. S. P. dis- solved in 20 mils ammonia water 10 per cent and 80 mils water. 10 grams molybdic acid dissolved in 42 mils ammonia water 10 per cent and poured into a mixture of 63 mils water and 63 mils nitric acid cone. 4 grams dissolved in 100 mils water. 10 grams dissolved in 100 mils water. 6 mils ammonia water . 10 per cent are satu- rated with hydrogen sulphide and then diluted with 40 mils ammonia water 10 per cent. To prepare the yellow ammonium sulphide add 1 to 2 grams of sulphur and shake until dis- solved. 1 gram dissolved in 100 mils sulphuric acid cone. 1 gram dissolved in 80 mils water and 20 mils alcohol. Place in tightly stoppered bottle and expose to temperature of steam for one hour. 10 grams dissolved in 100 mils water. Saturated solution. 3 mils dissolved in 100 mils water. Freshly pre- pared. 5 grams of equal parts by weight of the two salts dissolved in 100 mils water. 10 grams dissolved in 100 mils water. 10 grams dissolved in 100. mils water. Saturated solution. TABLES 1043 Calcium Hypochlorite. Calcium Sulphate. Chlorine Water. Cobalt Nitrate. Cobaltous Chloride. Cochineal. Congo Red. Copper Acetate. Copper Ammonium Sulphate. Copper Sulphate. Fehling's Solution. Formaldehyde-Sulphuric Acid. (Marquis Reagent) Fuchsin-Sulphurous Acid. Gold Chloride. Hematoxjdin. Iodeosin. Iodin (Wagner's Reagent). Iron Chloride (Ferric). Iron Sulphate (Ferrous). Lead Acetate. Lead Acetate. Alcoholic. Lead Subacetate. Litmus. 10 grams triturated with 20 mils water, filtered and repeated and the filtrate made up of 100 mils. Saturated solution. 0.5 gram potassium chlorate treated with 2 mils hydrochloric acid cone, in a flask fitted with a perforated stopper, warmed on steam-bath and when the flask is full of gas add 100 mils water. 10 grams dissolved in 100 mils water. 2 grams dissolved in 100 mils water and 1 mil hydrochloric acid. 1 gram macerated with 20 mils alcohol and 60 mils water for four days. Then filtered. 0.5 gram dissolved in 90 mils water and 10 mils alcohol. 1 gram dissolved in 1000 mils water. If solu- tion becomes cloudy add few drops acetic acid until clear. To be freshly made. To a solution of copper sulphate add ammonia until precipitate first formed is not quite dissolved. 10 grams dissolved in 100 mils water. (1) 7 grams copper sulphate dissolved in 100 mils water. (2) 35 grams Rochelle salt and 10 grams sodium hydroxide dissolved in 100 mils water. 10 mils formaldehyde solution in 50 mils sul- phuric acid. 0.5 gram fuchsin and 9 grams sodium bisulphite dissolved in 500 mils water and treated with 10 mils hydrochloric acid. 3 grams dissolved in 100 mils water. 0.2 gram dissolved in 100 mils alcohol. 0.1 gram dissolved in 100 mils alcohol. 2 grams with 6 grams potassium iodide dis- solved in 100 mils water. 10 grams dissolved in 100 mils of recently boiled water. To be freshly made; 1 gram dissolved in 10 mils of recently boiled water. 10 grams dissolved in 100 mils water. 3 grams of crystals dissolved in 100 mils alcohol. 18 grams lead acetate dissolved in 70 mils water, added to 11 grams of lead oxide (Litharge, PbO) in a porcelain dish, boiled for one-half hour, filtered and made up to 100 mils. Exhaust the powder three times with boiling alcohol, each treatment consuming an hour. Treat residue with an equal weight of cold water and filter. Then exhaust with five times its weight of boiling water, cool and filter. 1044 Magnesia Mixture. Magnesium Sulphate. Mercuric Chloride. Mercuric Chloride. Alcoholic. Mercuric Nitrate. Mercuric-Potassium Iodide. (Mayer's Reagent). Mercurous Nitrate. Methyl Orange. Methyl Red. Millon's Reagent. Oxalic Acid. Palladous Chloride. Phenolphthalein. Phosphomolybdic Acid. (Sonnenschein's Reagent). Phosphotungstic Acid. (Scheibler's Reagent). Picric Acid (Hager's Reagent). Platinic Chloride. Potassium Bromide-Br ornate. Potassium-cadmium Iodide. (Marine's Reagent). Potassium Carbonate. Potassium Chromate. Potassium Cyanide. Potassium Dichromate. Potassium Ferricyanide. Potassium Ferrocyanide. Potassium Hydroxide. Potassium Iodide. Potassium Permanganate. TABLES 10 grams magnesium sulphate and 20 grams ammonium chloride dissolved in 80 mils water and 42 mils ammonia water 10 per cent added. 10 grams dissolved in 100 mils water. 5 grams dissolved in 100 mils water. 6 grams dissolved in 100 mils alcohol 95 per cent. 40 grams red mercuric oxide dissolved in 45 grams of nitric acid (cone.) and 15 mils water. 1.3 grams mercuric chloride dissolved in 60 mils water added to 5 grams potassium iodide dis- solved in 10 mils water and made up to 100 mils. 10 grams in 100 mils water. Keep over metallic mercury. 1 gram dissolved in 1000 mils water. 0.2 gram dissolved in 100 mils alcohol. 10 grams mercury dissolved in 10 grams nitric acid (cone.) with the aid of heat, and then diluted with two volumes of water. 5 grams dissolved in 100 mils water. 5 grams dissolved in 100 mils water. 1 gram dissolved in 50 mils alcohol and 50 mils water added. Prepare ammonium phosphomolybdate and, after washing with water, boil with nitric acid and expel ammonia, evaporate to dryness and dissolve in 10 per cent nitric acid. 20 grams sodium tungstate and 15 grams sodium phosphate dissolved in 100 mils water con- taining a little nitric acid. 1 gram dissolved in 100 mils water. 13 grams dissolved in 100 mils water. To a concentrated solution of potassium hydrox- ide add bromine to saturation, boil off excess and dilute with an equal volume of water. 2 grams cadmium iodide added to a boiling solu- tion of 4 grams of potassium iodide in 12 mils water and mixed with an equal volume of saturated solution potassium iodide. 10 grams recently dehydrated at 130° C, dis- solved in 100 mils water. 10 grams dissolved in 100 mils water. To be freshly prepared. 1 gram dissolved in 10 mils water. 10 grams dissolved in 100 mils water. 10 grams dissolved in 100 mils water, freshly made. 10 grams dissolved in 100 mils water. 6 grams dissolved in 94 mils water. 20 grams dissolved in 100 mils water. 0.5 gram dissolved in 100 mils water. TABLES 1045 Potassium Sulphate. Potassium Sulphocyanide. Pyrogallol Alkaline. Resorcinol. Rosolic Acid. Silver Nitrate. Silver Nitrate, Ammoniacal. Silver Sulphate. Sodium Acetate. Sodium Bisulphite. Sodium Bitartrate. Sodium Carbonate. Sodium-Cobaltic Nitrite. Sodium Cyanide. Sodium Hydroxide. Sodium Hypobromite. Sodium Hypochlorite. Sodium Nitroprusside. Sodium Phosphate. Sodium and Potassium Tartrate. (Rochelle Salt). Sodium Sulphide. Sodium Tartrate. Sodium Thiosulphate. Stannous Chloride. 1 gram dissolved in 100 mils water. 1 gram dissolved in 100 mils water. To be freshly made as wanted; 14 mils 25 per cent pyrogallol in water and 86 mils 60 per cent potassium hydroxide. 1 gram dissolved in 100 mils water. 1 gram treated with 10 mils alcohol followed by 100 mils water. 5 grams dissolved in 100 mils water. 5 grams silver nitrate dissolved in 100 mils water and treated with ammonia water 10 per cent until precipitate is not quite redissolved. 1 gram treated with 100 mils of water. To be filtered as used. 10 grams dissolved in 100 mils water. To be freshly made; 30 grams dissolved in 100 mils water. If sulphur dioxide odor is strong add 20 per cent sodium hydroxide until scarcely noticeable. 3.5 grams tartaric acid boiled with 80 mils water, sodium carbonate added until neutral and then 3.5 grams tartaric acid added and solu- tion made up to 100 mils. 10 grams dissolved in 100 mils water. 4 grams cobalt nitrate and 10 grams sodium nitrite dissolved in 50 mils water, 2 mils acetic acid 36 per cent added and then water to 100 mils. To be freshly prepared. 1 gram dissolved in 10 mils water. 6 grams dissolved in 94 mils water. 1 mil bromin dissolved in 15 mils water con- taining 4 grams sodium hydroxide, then diluted to 20 mils. To be freshly prepared. 9 grams calcium hypochlorite triturated with 20 mils water, filtered and repeated, and washed with 10 mils water, filtrate mixed with 6.5 sodium carbonate monohydrated dissolved in 30 mils water, filtered, washed and made up to 100 mils. Freshly prepared. 1 gram dissolved in 10 mils water. Freshly pre- pared. 10 grams dissolved in 100 mils water. 10 grams dissolved in 100 mils water. 10 grams dissolved in 100 mils water. 10 grams dissolved in 100 mils water. 2.5 grams dissolved in 100 mils water. Pure tin boiled with hydrochloric acid cone, having metal in excess; when saturated, crys- tals will form, which are separated and drained and dissolved in 10 parts of water and the 1046 TABLES Starch. Sulphanilic Acid. Sulphomolybdic Acid. (Froehde's Reagent). Tannic Acid. Tartaric Acid. Turmeric. solution preserved in a well-stoppered bottle containing tin foil. 0.5 gram starch mixed with 10 mils water and added to 90 mils boiling water. 0.5 gram dissolved in a mixture of 15 mils glacial acetic acid and 135 mils recently boiled water. 10 grams molybdic acid or sodium molybdate dissolved in 100 mils sulphuric acid cone. 10 grams dissolved in 10 mils alcohol and 90 mils water added. 10 grams dissolved in 30 mils water. Powder is digested with several portions of water which are discarded. Then treated with six times its weight of alcohol for several days and filtered. TABLES 1047 EQUIVALENTS OF WEIGHTS AND MEASURES From 480 Grains Down Grains Metric weight and measure. Gram or cm. 1 Minims (of Water at 4° C.) Grains Metric weight and measure, Gram or cm. Minims (of Water at 4° C.) 480 31 . 103 504.8 240 15.552 252.4 478.4 31 503.1 231.5 15 243.5 475.4 30.805 500 228.2 14.786 240 463.0 30 486.9 218.75 14.175 230.1 456.4 29 . 573 480 216.1 14 227.2 450 29.160 473.3 210 13.608 220.9 447.5 29 470.7 200.6 13 211.0 437.5 28.350 460.1 199.7 12.938 210 432.1 28 454.5 185.2 12 194.8 427.9 27 . 725 450 420 27.216 441.7 180 11.664 189.3 416.7 27 438.2 171.1 11.090 180 401.2 26 422.0 169.8 11 178.5 399.3 25.876 420 154.3 10 162.3 390 25.272 410.2 150 9.720 157.8 385.8 25 405.8 142.6 9.242 150 380.3 24.644 400 138.9 9 146.1 370.8 24.028 390 123.5 8 129.8 370.4 24 389.5 360 23.328 378.6 120 7.776 126.2 354.9 23 373.3 114.1 7.393 120 342.3 22.180 360 109.37 7.087 115.0 339.5 22 357.1 108.0 7. 113.6 330 21.384 347.1 100 6.480 105.2 324.1 21 340.8 95.1 6.161 100 313.8 20.331 330 92.6 6 97.4 308.6 20 324.6 80 5.184 84.1 77.2 5. 81.2 76.1 4.929 80 61.7 4 64.9 300 19 . 440 ■ " ■ 315.5 60 3.888 63.1 293.2 19 308.4 57.0 3.697 60 285.2 18.483 300 54.69 3.544 57.5 277.8 18 292.2 47.5 3.081 50 270 17.496 284.0 50. 3.240 52.6 262.4 17 275.9 46.3 3 48.7 256.7 16.635 270 42.8 2.772 45 246.9 16 259.7 40 2.592 42.1 38.0 2.464 40. 33.3 2.156 35 30.9 2 32.5 1048 TABLES EQUIVALENTS OF WEIGHTS AND MEASURES— Continued Grains Metric weight and measure, Gram or cm. Minims (of Water at 4° C.) Grains Metric weight and measure, Gram or c.c. Minims (of Water at 4° C.) 30 1.944 31.55 10 0.648 10.52 28.52 1.848 30 9.51 0.616 10 23.77 1.540 25 9 0.583 9.47 20 1.296 21.00 8.56 0.554 9 19.02 1.232 20 8 0.518 8.41 15.4324 1 16.23 7.71 0.5 8.12 7.61 0.493 8 7 0.454 7.36 6.66 0.431 7 6 0.389 6.31 5.70 0.370 6 15 0.972 15.78 5 0.324 5.26 14.26 0.924 15 4.75 0.308 5 14 0.907 14.72 4 0.259 4.21 13.31 0.863 14 3.80 0.246 4 13 0.842 13.67 3 0.194 3.16 12.36 0.801 13 2.85 0.185 3 12 0.778 12.62 2 0.130 2.10 11.41 0.739 12 1.90 0.123 2 11 0.713 11.57 1 0.06480 1.0517 10.46 0.678 11 0.9508 0.06161 1 TABLES 1049 EQUIVALENT WEIGHTS AND MEASURES From 5 Grains Down Grains Grams Grains Grams In decimal fractions In common fractions (Approximate) In decimal fractions In common fractions (Approximate) 0.324 5 5 0.0285 0.44 7/16 0.291 4.5 H 0.0259 0.40 2/5 0.259 4 4 0.0246 0.38 3/8 0.227 3.5 3* 0.0201 0.31 5/16 0.194 3 3 0.0162 0.25 1/4 0.162 2.5 9! 0.0123 0.19 3/16 0.130 2 2 0.0084 0.13 1/8 0.097 1.5 H 0.0039 0.06 1/16 0.065 1 l 0.0032 0.05 1/20 0.0026 0.04 1/25 0.0022 0.033 1/30 0.0609 0.94 15/16 0.0018 0.028 1/36 0.0583 0.90 9/10 0.0016 0.025 1/40 0.0570 0.88 7/8 0.0013 0.02 1/50 0.0531 0.82 13/16 0.0011 0.017 1/60 0.0518 0.80 4/5 0.0010 0.015 1/64 0.0486 0.75 3/4 0.0006 0.01 1/100 0.0447 0.69 11/16 0.0005 0.008 1/128 0.0408 0.63 5/8 0.0004 0.0065 1/160 0.0363 0.56 9/16 0.0003 0.005 1/210 0.0324 0.5 1/2 0.0002 0.003 1/320 0.0001 0.0015 1/640 INDEX Abies balsamea, 486 — fraseri, 486 — picea, 486 Abrastol, 784 Absinthe, 391, 615 Absinthiin, 394 Acacia, 463 Acer spictum, 446 Acetaldehyde, 585 Acetamide, 821 Acetanilid, 833 — separation of from caffein, 837 antipyrin, 839 quinin sulphate, 841 morphin, 843, 847 salicylate, 845 — estimation of in liquid headache tures, 849 Acetates, assay of, 630 Acetone, 600 — determination of, 603 in presence of ethyl alcohol, — resorcinol, 604 Acetopiperon, 359 Acetozone, 569 Acetphenetidin, 854 — separation of from caffein, 857 and codein, 858 salol, 859 quinin, 863 ■ acetanilid, 864 and antipyrin, 866 Acetylparaminophenol salicylate, 682 Acoin, 141 Aconite, assay, 26 Acid, Abietic, 488 — Acetic, 629 — Acetyl Salicylic, 680, 686 — • Aconitic, 270, 657 — Adonidic, 339 — Anacardic, 700 — Angelic, 640 604 685 Acid, Arachidic, 633 — Arsanilic, 876 — Asparaginic, 647 — Atropic, 111, 669 — Barbituric, 825 — Behenic, 633 — Benzoic, 659 estimation of, 662 separation of from cinnamic, 663 salicylic, 662 — Boric, 966 estimation of, 966 — Cacodylic, 973 — Caffeic, 700 — Caincic, 701 — Camphoric, 612 — Camphoronic, 613 — Carbolic, 754 estimation of, 756 of in presence of alcohol, 541 — Cerotic, 634 — Chlorogenic, 297 — Cholalic, 723 — Chromic, 1012 — Chrysophanic, 366, 367, 374 — Cinnamic, 362, 668 estimation of in aromatic balsams, 715 aldehyde, 595 — Citric, 654 estimation of, 656 — Coumaric, 341, 362, 691 — Cresylic, 758 — Cro tonic, 640 — Dihydroxycinnamic, 387, 450 — Dimethoxycinnamic, 444 — Ellagic, 432, 694 — Embelic, 701 — Ferulic, 507, 692 — Filicic, 398, 701 — Formic, 626 1051 1052 INDEX Acid, Formic, estimation of, 627 separation from acetic, 634 — Gallic, 357, 366, 485, 693 — Gallotannic, 695 — Hippuric, 663 — Hydracrylic, 644 — Hydriodic, 950 estimation of, 951 — Hydrobromic, 950 — Hydrochloric, 949 — Hydrocyanic, 345 estimation of, 345 in oil of bitter almond, 346 separation of, 345 — Igasuric, 251, 700 — Illurinic, 491, 495 — Iodic, 953 — Ipurolic, 385 — Isatropic, 111 — Jalapinolic, 387 — Kino-tannic, 484 — Lactic, 643 estimation of, 645 — Z-mandelic, 341 — Margaric, 632 — Meconic, 206 — Melilotic, 691 — Methylene Hippuric, 663 — Myristic, 632 — Nitroparaphenolsulphonic, 718 — Nonylic, 632 — Nucleic, 724, 895 — Oleic, 941 — Ophelic, 352 — Orthosulphocarbolic, 718 — Oxalic, 646 — Palmitic, 632 — Para-creosotic, 672 — Pelargonic, 632 — Perchloric, 953 — Phenolsulphonic, 717 — Phthalic, 665 — Picric, 756 — Piperonylic, 358 — Polygalic, 329 — Protocatechuic, 693 — Quillaic, 328, 701 — Quinic, 700 — Rheinolic, 366-369 — Salicylic, 370, 429, 436, 671 estimation of, 674, 675, 676 in aspirin, 687 Acid, Formic, derivatives of, 677 — Santoninic, 393 — Sativic, 633 — Sinapic, 348 — Sozolic, 708 — Stearic, 633 — Strophanthic, 313 — Succinic, 647 — Sulphanilic, 717 — Tannic, 695 estimation of, 696 — Tartaric, 648 estimation of, 650 — Taurocholic, 722 — Tiglic, 275, 640 — Trichloracetic, 593 — Trichlorbutyric, 593 — Tropic, 110, 670 — Truxillic, 126 — Valerianic, 447, 448, 631 Acids, organic aliphatic, 624 — acetic series, separation of, 637 estimation of in admixture, 638 — acrylic series, 639 Aconite, Japanese, 264 — species, 265 Aconitin, 267 — separation and estimation, 272 Aconitum napellus, alkaloids of, 264 — fisheri, 264 Acetophenone, 605 Actea alba, 339 — rubra, 339 — spicata, 339 Adalin, 823 Adenin, 296 Adonis vernalis, 339 Adlumidin, 248 Adlumin, 248 Adlumia cirrhosa, alkaloids of, 244 Adonidin, 339 Adrenalin, 827 Agathin, 683, 808 Agropyron repens, 415 Airol, 994 Albargin, 972 Albaspidin, 398 Alcohol, Anisyl, 554 — Butyl, 542 — Cinnamyl, 553 — Cuminic, 553 — determination, 2 INDEX 1053 Alcohol Ethyl, 537 , determination of in presence of methyl, 538, 540 ether mixture, 539 estimation of in presence of acid, 541 — Methyl, 530 estimation of, 535 determination of in presence of ace- ton, 603 — Ortho-oxybenzyl, 553 — Propyl, 542 — Salicyl, 553 Alcohols, 529 — general properties of monohydric, 530 — identification of in oils, 935 Alcoholometric tables, 3 Aldehyde, Anisic, 456 — Cinnamic, 459 — estimation of by Burgess method, 932 — identification and determination in oils, 931 Aldehydes, 570 — determination of, 586 Aletris farinosa, 331 Afridol, 980 Alizarin, 528 Alkaloids, definition, 71 — estimation of, 78 — Heikel's method, 79 — microchemical examination, 76 — separation and purification, 72 — Solanum, distinguishing tests, 112 AUyl isothiocyanate, 348 Allspice, 457 Aloes, 360 Aloin, 362, 364 Alpha-naphthol, 779 Alphol, 682, 782 Alphozone, 569 Altingia excelsa, 714, 716 Alstonia constricta, alkaloids of, 181 Alstonin, 181 Aluminol, 782 Aluminium, 1013 — beta-naphtholdisulphonate, 782 — estimation of, 1013 — hydrate, 1013 — and potassium sulphate, 1013 — silicate, 966, 1013 Alypin, 145 Ambrosia elatior, 396 Aminoacetphenetidin, 867 Aminophenols, 853 Ammonia, 1025 — estimation of in meat extract, 890 spirit, 1029 liniments, 1029 Ammoniacum, 496 Ammoniated mercury, 980 Ammonium, 1025 — bromide, 1026 — carbonate, 1026 — chloride, estimation of in antiseptic tablets, 985 antiseptic tablets, 1025 — citrate, 654 — salts, estimation of, 1029 — succinate, 647 Amygdalin, 343 Amygdophenin, 870 Amyl bromide, 734 Amyl iodide, 735 Amylene, 735 Amyl nitrite, 733 assay, 734 Amyloform, 578 Amyl salicylate, 735 — valerate, 735 Anacardium occidentale, 700 Analgen, 816 Anaesthesin, 143 Anapyralgin, 871 Androsin, 324 Anesthetics, synthetic, 137 Angelica, 631, 640, 641 Anilin, 831 Anise, 455 — ketone, 456 Anisic aldehyde, 596 Angostura bark, alkaloids of, 181 Anhalamin, 308 Anhalin, 307 Anhalonidin, 307 Anhalonium, assay, 27 — fissuratum, alkaloids of, 307 Anthraquinone, 528 — drugs, 360 identification of, 376 Antiarin, 314 Antiaris toxicaria, 314 Antimony, 1000 — and potassium tartrate, 1000 — estimation of, 1001 1054 INDEX Antimony oxide, 1001 — sulphide, 1001 — sulphurated, 1000 Antinosin, 667 Antipyrin, 792 — estimation of, 795 in tablets with caffein, 801 — iodide, 804 — mandelate, 803 — monobromide, 804 — resorcylate, 804 — salicylate, 803 — salicylacetate, 804 — separation of from acetanilid and sul- phonal, 800 ■ — acetphenetidin and codein, 797 Antithermin, 791 Apiol, 787, 935 — dill, 419 Apocodein, 204 Apocynamirin, 324 Apocynum, assay, 33 — cannabinum, glucosides of, 324 — androsaemifolium, glucosides of, 324 — pubescens, glucosides of, 324 Apomorphin, 202 Arabinose, 617 Aralia racemosa, 329 — nudicaulis, 329 Arbutin, 334, 335 Arctium lappa, 451 Areca catechu, alkaloids of, 89 Arecaidin, 91 Arecolin, 90 Argentamin, 809, 975 Argentol, 816 Argonin, 973 Argyrol, 896, 973 Arhovin, 808 Aristoehin, 175 Aristolochia serpentaria, 406 — reticulata, 406 Arnica montana, 454, 640 Arrhenal, 875 Arsacetin, 876 Arsenic, 997 — compounds, organic, 873 — detection and determination, 19 — estimation of in presence of other metals, 999 — peptonate, 882 — tribromide, 998 Arsenous oxide, 997, 998 estimation of, 999 Arsen-triferrin, 882 Arsenoferratin, 881 Arsenoferratose, 881 Arsphenamine, 877 Asarol, 786 Asarum canadense, 406 Ascaridole, 395 Aseptol, 718 Artemisia absinthium, 391, 394 — cina, 391 — maritima, 391 — pontica, 392 — species, 391 Asafetida, 506 — lead number of, 509 Asarone, 419 Ash, determination, 6 Asclepias tuberosa, 437 — species, 438 Asparagin, 647 Aspidinol, 398 Aspidosamin, 180 Aspidosperma, assay, 28 Aspidosperma Quebracho-bianco bark, alkaloids of, 180 Aspidospermatin, 180 Aspidospermin, 180 Aspirin, 680, 686 Assays, crude drug, 23 Lloyd procedure, 68 Atophan, 817 Atoxyl, 876 Astragalus species, 467, 469 Atisin, 270 Atomic weights, 1033 Atropa belladonna, alkaloids of, 100 Atropamin, 110 Atropin, 104 — determination of in tablets, 114 Atropurol, 434 Atrocin, 109 Balm of Gilead, 490 Balsam, 481 — Canada, 486, 489 — Copaiba, 490 — Gurjun, 495 — Honduras, 713 — Mecca, 490 INDEX 1055 Balsam Peru, 705 — , Tolu, 705 Balsamodendron gileadense, 490 — indicum, 505 — kafal, 505 Baptisia tinctoria, alkaloids of, 97 Barium sulphide, 955 Barosma betulina, 787 — crenulata, 787 Baumes, 702 Bdellium, 505 Beef peptone, 893 — jelly, 893 — iron and wine, 893 Belladonna, assay, 28 — plaster, assay, 115 Benzacetin, 680 Benzaldehyde, 594 — cyanohydrin, 344 — estimation of, 594 Benzanilid, 852 Benzoin, 702 Benzoiin, 606 Benzol, 520 Benzophenone, 606 Benzosalin, 683, 728 Benzosol, 768 Benzoyl ecgonin, 123 Benzyl morphin, 206 Benzylideneacetone, 604 Berbamin, 234 Berberin, 232 Berberis aquifolium, alkaloids of, 228 Beta-naphthol, 779 benzoate, 782 estimation of, 781 hydroxytoluic acid, 692 lactate, 784 salicylate, 783 Betol, 682, 783 Betula lenta, 687 Bile acids, 721 Bicuculla canadensis, 237 Bikhaconitin, 269 Bismal, 994 Bismuth, 992 — betanaphtholate, 783, 993 — estimation of, 995 — electrolytic, 997 — oxide, 993 — oxyiodogallate, 99-± — salicylate, 672 Bismuth, salts, estimation of in presence of mercury, 988 — subcarbonate, 993 — subgallate, 694 — subnitrate, 993 — tribromphenate, 757 Bistort, 376 Bitter tonic drugs, 348 Black haw, 446 Blood tonics, 327 Bocconia frutescens, 244 — cordata, alkaloids of, 244 Borneol, 554 . — brom-valerate, 555 — isovalerate, 555 Bornyval, 555 Brassica, glucosides of, 347 — junicea, 347 — niger, 347 Brenzcain, 148, 769 Bromal, 591, 757 — hydrate, 591 Bromalin, 595 Bromamide, 832 Brometone, 743 Bromin, 946 Bromoform, 743 Bromural, 823 Brovalol, 555 Brucin, 256 Bryonia alba, 448 — dioica, 448 Bryonol, 449 Bryony root, 448 Buckthorn, 373 Buchu, 787 Bulbocapnin, 238 Burdock, 451 Butternut root bark, 357 Butyl-chloral, 591 hydrate, 591 Cactus, alkaloids of, 306 Caffein, 287 — estimation of in coffee, 290 granular effervescent salt, 653 tea, 289 Calabar bean, alkaloids of, 302 Calcium, 1019 — carbonate, 1019 — dibrombehenate, 634 — eosolate, 771 1056 INDEX Calcium, estimation of, 1020 — glycerophosphate, 750 — guiacolmonosulphonate, 771 — hypophosphite, 1019 — hypochlorite, assay, 952 — monoiodobehenate, 634 — peroxide, 1019 — phosphate, 1019 — sulphide assay, 955 Calendula officinalis, 454 Calomel, 979 — colloidal, 982 — estimation of in tablets with santonin, 394 — separation of from bismuth subcarbon- ate, 988 Calomelol, 982 Camphor, 608 — estimation of in spirit of camphor, 611 tablets, 614 — monobromated, 613 Cannabinol, 422 Canadin, 233, 432 Cannabis sativa, 421 assay, 30 Cantharides, assay, 31, 412 — plaster, assay of, 412 — species, 411 — tincture, assay of, 412 Cantharidin, 411 Capsaicin, 402 Capsicum, estimation of pungency, 403 — species, 401 Carbohydrates, 616 — estimation of in infant foods, 619 — identification of, 617 Carbon, 961 Carbonates, estimation of, 962, 963 Carbosant, 735 Cardamon, 458 Carica papaya, 901 Carthamus tinctorius, 455 detection of in saffron, 417 Carum carvi, 456 Carvacrol, 765 Carvone, 456, 606 — estimation of, 607, 608 Caryophyllene, 458, 491 Caryophyllus aromaticus, 457 Cascara sagrada, 371 Casein, 895 Cashew nut, 700 Cassia, 458 — acutifolia, 370 — angustifolia, 370 — marilandica, 370 Castoria, 370 Catechol, 766 Catecholmonoethylester, 774 Caulophyllosaponin, 330 Caulophyllum thalictroides, 330 Caulosapogenin, 330 Caulosaponin, 330 Cephaelin, 225 Cellulose, 617 — estimation of, 622 Cephselis acuminata, 223 — ipecacuanha, 223 Cerium, 1018 — oxalate, 1018 Cevadilla seed, alkaloids of, 274 Cevadin, 275 Cevin, 275 Chamaelirium luteum, 331 Charcoal, 961 Chavicol, 785 Chelidonium majus, alkaloids of, 244 Chelerythrin, 246 Chelidonin, 246 Chenopodium ambrosioides, 395 Cheronium opopanax, 505 Cherry-laurel water, 344 Chicle, 512 Chimaphila umbellata, 334, 335 Chinaphenin, 175 Chinosol, 815 Chiococca anguituga, 701 Chirata, 351 Chiratin, 352 Cholin, 425, 450, 451 Chondrodin, 306 Chloral, 587 — acetone chloroform, 592 Chloralurethane, 591 Chloralformamide, 591 Chloral dimethyl-ethyl carbinol, 590 Chloral hydrate, 586 estimation of, 589 Chloralimide, 592 Chloralose, 592 Chlorates, estimation of, 953 Chloretone, 147 Chlorine, 946 Chloroform, 738 INDEX 1057 Chloroform, estimation of, 742, Cholesterol, 917 Chondrodendron tomentosum, alkaloids of, 305 Chromium, 1012 — estimation of, 1012 Chrysarobin, 374 Chrysoeridol, 441 Cimicifuga racemosa, 339 Cinchamidm, 155 Cinchona, alkaloids of, 149 estimation of, 170 identification of, 167 separation of, 174 — assay, 33 — barks, 150 Cinchonamin, 155 Cinchonicin, 167 Cinchonidin, 154 Cinchonin, 152 Cinchotenin, 154 Cinchotin, 155 Cineol, 559 — estimation of in oil of eucalyptus, 560, 561 Conium, assay, 38 Cinnamein, 701, 702 Cinnamene, 521 Cinnamonum camphora, 608 — cassia, 458 — louriria, 458 — zeylandicum, 458 Cinnamylmetacresol, 761 Citarin, 657 Citral, estimation of, 586 Citrullol, 354, 434 Citrullus colocynthus, 353 Claviceps purpurea, alkaloids of, 300 Clemen's solution, 998 Cloves, 457 Cluytianol, 451 Cocain, 119 — cinnamyl, 121 — separation and identification of, 128 Coca, alkaloids of, 118 — assay, 35 — determination of alkaloids in, 138 — identification of, 127 — leaf constituents of, 136 Cochlospermum gossypium, gum of, 470 Cocillana bark, 426 Cocoa butter, 935 Cocculus indicus, 399 Codamin, 196 Codein, 191 — colorimetric, estimation of, 216 — estimation of in admixture with caffein acetanilid, acetphenetidin, and quinin, 218 — estimation of in opium, 216 Coffee, 284, 297 — estimation of caffein in, 290 Cohosh, blue, 330 — black, 339 — red, 339 Colalin, 724 Colchicin, 281 — estimation in globules of and methyl- salicylate, 283 Colchicein, 281 Colchicum autumnale, 281 — alkaloids of, 36 — assay, 36 Collinsonia canadensis, 442 Colocynth, 353 — identification of, 355 Colophony, 488 — in asafetida, 510 Columbin, 235 Commiphora africana, 505 — species, 503 Condimental drugs, 455 Conhydrin, 85 Conicein, 85 Coniin, 83 — estimation of, 86 Coniferin, 414 Coniferyl alcohol, 414 Conium, assay, 38 — detection of in anise, 455 Conium maculatum, alkaloids of, 82 Conquinamin, 165 Convallaria assay, 33 — majalis, 322 Convallamarin, 322 — glucosides of, 322 Convallarin, 322 Convolvulinolic acid, 385 Convolvulus scammonia, 382 Copaiba, 490 — African, 495 — detection of, 496 — Maracaibo, 491 — Maranham, 491 1058 INDEX Copaiba, Para, 491 Copper, 989 — estimation of, 989, 991 Coriander, 457 Coriandrum sativum, 457 Corycavamin, 238 Corybulbin, 238 Corycavin, 238 Corydalin, 238 Corydalis canadensis, 237 — ■ cava, alkaloids of, 237 Corydin, 238 Coryfin, 558 Corytuberin, 238 Cosaprin, 717 Coto bark, 358 Cotoin, 358 Cotton root bark, 436 Cough remedies, 340 Coumarin, 691 Cramp bark, 446 Creatin, estimation of in meat extract, 891 Creatinin, estimation of, 892 Creosol, 773 Creosotal, 772 Creosote, 772 — carbonate, 772 — oleate, 772 — phosphate, 772 — phosphite, 772 — tannate, 772 — valerate, 772 Cresalols, 761 Cresatin, 761 Cresols, 758 — estimation of, 758 Crocus sativus, 416 Crurin, 814 Cryptopin, 198 Cubeb, 419 Cubebin, 420 Culver's root, 443 Cuminic aldehyde, 597 Cuprein, 165 Cuprol, 725 Curare, alkaloids of, 250 Cusco bark, alkaloids of, 166 Cuscohydrin, 124 Cusparia officinalis bark, alkaloids of, 181 Cusparidin, 181 Cusparin, 181 Cyanogenetic glucosides, 340, 467 Cycloform, 145 Cymene, 521 Cynoctonin, 270 Cynotoxine, 324 Cytisin, 97 Cytisus laburnum, alkaloids of, 97 — scoparius, alkaloids of, 94 Damiana, 436 — detection of in tonics, 437 Dandelion root, 450 Datura stramonium, alkaloids of, 100 Delphinin, 98 Delphinium staphisagria, alkaloids of, 98 — consolida, alkaloids of, 98 Delphinoidin, 98 Delphisin, 98 Dermatol, 694 Dextrin, 617 — estimation of in infant foods, 619 Dextrose, 617 — estimation of in infant foods, 619 Diacetyl morphin, 204 Diacetylparamidophenol, 871 Diacetyltannin, 697 Diaphtherin, 817 Diaphtoi, 817 Diaspirin, 680 Diastase, 907 Diathesin, 553 Dicentrin, 238 Dicinchonicin, 167 Diethylenediamine, 809 Diethylsulphonediethylmethane, 747 Diethylsulphonedimethylmethane , 746 Diethylsulphonemethylethylmethane, 747 Digestives, 896 Digitalein, 320 Digitalin, 317 — commercial, 320 Digitalis, assay, 39 — examination of tincture by Martin- dale's method, 321 — purpurea, glucosides of, 315 — tests for, 321 Digitaligenin, 318 Digitalose, 318 Digitonin, 318 Digitoxigenin, 317 Digitoxin, 316 — determination, 42 Digitoxose, 317 INDEX 1059 Diiodobetanaphthol, 784 Diiodoform, 745 Diiodoparaphenol sulphonic acid, 719 Diisobutylcresol iodide, 760 Dimethylacetal, 735 Dimethylaminotetraminoarsenobenzene, 881 Dimethylhomocatechol, 773 Dimethyl piperazine, 810 tartrate, 810 Diosphenol, 787 — detection of, 789 Diphyllin, 247 Diquinicin, 167 Dionin, 205 Diorthocumarketone, 605 Dita bark, alkaloids of, 181 Dithion, 679 Dock, yellow, 375 — bitter, 375 Dorema ammoniacum, 496 Dormiol, 590 Dryobalanops camphora, 554 Dryopteris filix-mas, 397 — marginalis, 397 Duboisia Hopwoodii, alkaloids of, 99 — myoporoides, alkaloids of, 100 Dulcin, 665, 871 Duotol, 768 Dutch liquid, 731 Ecballium elaterium, 352 Ecgonin, 125 Echinacea angustifolia, 454 — pallida, 454 — purpurea, 454 Elarson, 883 Elaterin, 352 Electromercurol, 981 Elatteria cardamomum, 458 Embelia ribes, 701 Emetin, 225 Emmenagogue pills, 338 Emodin, 367, 368, 373 — aloe, 362, 363 — monomethyl ether, 366, 367, 368 Empyroform, 580 Emulsion, estimation of oil in, 922 Enesol, 883 Eosote, 772 Epicarin, 692 Epinephrin, 827 Epinephrin, estimation of, 829 Ergot, alkaloids of, 300 — assay, 43 Ergotinin, 301 Ergotoxin, 301 Ergoxanthein, 302 Eriodictyol, 440 Eriodictyon californicum, 438 Eriodonol, 441 Erystamine, 585 Erythrol tetranitrate, 738 Eschscholtzia californica, alkaloids of, 244 Eseramin, 304 Eserolin, 304 Estoral, 558 Ether, 562 — determination of alcohol and water in, 567 — estimation of in alcohol mixture, 539 Ethereal salts, 727 Ethyl acetate, 732 — benzoate, 733 — bromide, 730 — carbolate, 758 — carbonate, 824 — chloride, 729 — cinnamate, 733 — diiodosalicylate, 733 — formate, 733 — iodide, 731 — - lactate, 731 — morphin, 204 — nitrite, 732 — valerate, 733 Ethylenediamine, 808 Ethylene dibromide, 732 — dichloride, 731 Ethylenetetraiodide, 745 Ethylidene chloride, 731 Ethylmercaptan, 746 Ethylthiocarbimide, 733 Eucain alpha, 138 — beta, 138 Eucalyptol, 559 Eucalyptus rostrata, 484 Eucodein, 204 Eudoxin, 667 Eugallol, 778 Eugenoform, 786 Eugenol, 457, 458, 785 — benzoate, 786 — cinnamate. 786 1060 INDEX Euguform, 771 Euonymol, 434 Euonymus americanus, 433 — atropurpureus, 433 Euonysterol, 434 Eupatorin, 410 Eupatorium glutinosum, 48 — rebaudianum, 410 Euphorbia pilulifera, 432 Euphorin, 823 Eupthalmin, 140 Eupyrin, 870 Euquinin, 175 Euresol, 775 Eurobin, 375 Europhen, 760 Euscopol, 112 Erythroxylon coca, alkaloids of, 118 Exalgin, 851 Exogonium purga, 382 Extract, codliver, 894 — Goulard's assay of, 977 — malt, 911 — meat, 887 analysis of, 887 estimation of glycerin in, 548 Fabiana imbricata, 441 Ferro sajodin, 634 Female remedies, 330 Feminella, 417 Fenchone, 456, 615 Fennel, 456 Ferratin, 1010 Ferrinol, 725 Ferrous carbonate assay, 1004 — hypophosphite, 1009 — salts, estimation of iron in, 1007 Ferropyrin, 803 Ferula asafetida, 506 — fetida, 506 — rubricaulis, 506 — sumbul, 435 Fiber crude, estimation of, 622 Fibrolysin, 824 Filicin, 397 Filmaron, 398 Fish berry, 399 Flavaspidic acid, 398 Flavaspidin, 398 Fluorescein, 775 Fluoroform, 743 Fceniculum vulgare, 456 Formaldehyde, 572 — acetamide, 579 — acetate, 578 — estimation of, 573, 574 Formaloin, 579 Forman, 558, 579 Formanilid, 852 Formicin, 579 Formopyrin, 580, 804 Formylphenetidin, 868 Fortoin, 359, 579 Fowler's solution, 998 assay of, 999 Francois reagent. 740 Fraxinus ornus, 550 Fumaria officinalis, alkaloids of, 244 Galactochloral, 592 Galactose, 617 Galbanum, 498 Galipidin, 181 Galipin, 181 Galipoidin, 181 Gallanilide, 695, 852 Gallanol, 695, 852 Gallicin, 695, 728 Gallobromol, 695 Galloformin, 695 Gallogen, 694 Gamboge, 499 Garcinia morella, 499 Gaultheria leucoceupa, 687 — procumbens, 687 — punctata, 687 Geissospermin, 182 Geissospermum vellosi, alkaloids of, 182 Gelsemin, 240 Gelsemium, assay, 45 Gelsemium sempervirens, alkaloids of, 239 — alkaloids, separation of, 242 Geneserin, 305 Genesta tinctoria, alkaloids of, 97 Gigartina mamillosa, 466 Ginger, 404 — wild, 406 Ginseng, 330 Gitalin, 319 Gentiamarin, 349, 350 Gentiana Elliotii, 349 — lutea, 348 Gentian root, glucosides of, 348 INDEX 1061 Gentiin, 349, 351 Gentiopicrin, 349, 350 — separation of, 351 Gitonin, 320 Glaucin, 238, 248 Glaucinum corniculatum, alkaloids of, 244 Glucose, commercial determination, 18 Glucosides, 309 — reactions of, 310 Glutei, 578 Glycerin, 542 — affect on alcohol determination, 2 • — estimation of, 548 in meat juices and extracts, 548 pharmaceutical preparations, 549 — identification of, 545 Glycerophosphates, 748 — estimation of, 961 Glycerophosphoric acid, 748 Glycocholic acid, 642, 722 Glycosal, 681 Glycothymoline, 556 Glycyrrhiza glabra, 407 — glandulifera, 407 Gold, 991 — and sodium chloride, 992 — estimation of in medicines, 992 Gnoscopin, 200 Goa powder, 374 Granular effervescent salt, analysis of, 653 estimation of carbonate in, 963 Grindelia species, 452 Grindelol, 453 Griserin, 816 Guacamphol, 769 Guaethol, 774 Guaiacum officinale, 482 — sanctum, 482 Guaiamar, 769 Guaiacol, 767 — benzoate, 768 — benzyl-ester, 769 — camphorate, 769 — carbonate, 768 — cinnamate, 769 — glyceryl-ether, 769 — methyl-glycolate, 770 — ■ phosphate, 770 — phosphite, 770 — salicylate, 770 — valerate, 770 Guaiaquin, 177 Guaiaquinol, 177 Guaiasanol, 148 Guaicyl, 148 Guanin, 296 Guarana, assay, 46 Guarea rusbii, 426 Gum acacia, 463 — arabic, 463 determination of, 464 — cauchillo, 513 — chewing, 512 , — indian, 469 — mesquite, 465 — quince seed, 466 — red, 484 — Senegal, 463 — tragacanth, 467 determination of, 468 Gum plant, 452 Gums, 460 — characteristics of, 462 — classification of, 461 Guvacin, 91 Gymnosporia, manna-like incrustation on, 552 Gynoval, 555 Halogen acids, 949 estimation of, 951 oxyacids, 952 Halogens, identification and determina- tion, 945, 946 Hamamelis virginiana, 428 Hardwickia manii, 490 — pimenta, 490 Harmalin, 263 Harmalol, 263 Harmin, 263 Headache mixtures, assay of, 795, 797 Heart tonic drugs, 311 Hedeoma pulegioides, 615 Hediosit, 618 Hedonal, 824 Hegonon, 973 Heliotropin, 599 Helleborein, 338, 339 Helleborin, 338 Helleborus niger, glucosides of, 338 Helmitol, 584 Helonias, 331 Hemaboloids, 1010 1062 INDEX Hemogallol, 1011 Henna, 371 Heroin, 204 — separation of from codein and morphin, 220 morphin, 220 Hetacresol, 761 Hetralin, 583, 776 Hexal, 583 Hexamethylenetetramine, 580 — bromethylate, 585 — citrate, 584 — estimation of, 581 in tablets, 581 granular effervescent salt, 653 — oxymethylsulphonate, 585 — resorcinol, 583 — salicylate, 584 — salicyl sulphonic acid, 583 Hippol, 663 Histosan, 771 Hoang-Nan, 251 assay, 46 Holocain, 141 Homatropin, 112 Homocatecholmethylester, 773 Homochelidonin, 244, 247 Homoeriodictyol, 440 Homoeuonysterol, 434 Homosaligenin, 787 Homotaraxasterol, 450 Hops, 424 Humulol, 425 Humulus lupulus, 424 Hydrangea arborescens, 427 Hydrargryol, 718 Hydrastin, 230 — separation from berberin, 236 Hydrastinin, 231 Hydrastis canadensis, alkaloids of, 228 Hydrastis, assay, 46 Hydrazine, 791 Hygrin, 124 Hydrocarbons, 518 — cyclic, 521 — determination of, 519 Hydrocotoin, 358 Hydrocotarnin, 200 Hydrogen sulphide, 955 Hydro-quebrachin, 180 Hydroquinidin, 164 Hydroquinin, 164 Hydroquinone, 776 Hydroxyhydroquinone, 779 Hydroxyquinolin, 815 Hyoscin, 100 Hyoscyamin, 108 Hyoscyamus assay, 48 Hyoscyamus niger, alkaloids of, 100 Hypnal, 592, 805 Hypnoacetin, 870 Hypnone, 605 Hypophosphites, 961 Hypoxanthin, 295 Ichthoform, 580 Ichthyol compounds, 719 Ignatia, 251 — assay, 46 Imperatoria ostruthium, 265 Incarnatrin, 431 Indaconitin, 269 Infant foods, analysis of, 619 Inulin, 450, 452, 617 Iodanisol, 745 Iodides, estimation of, 951 lodin, 945 — estimation of, 947, 949 in ointment, 948 organic compounds, 954 — peroxide, 953 Iodoform, 743 — estimation of, 744 Iodoformal, 585 Iodoformin, 585 Iodol, 812 Iodolin, 815 Iodomethylphenylpyrazolon, 806 iodone, 667 Iodophen, 667 Iodylin, 679 Iothion, 745 Ipecac, alkaloids of, 222 — assay, 48 — wild and false, 223 Ipomcea orizabensis, 382, 386 — purga, 382 — purpurea, 382 — turpethum, 388 Ipuranol, 341, 386, 416 Ipurganol, 384 Iris florentina, 415 — versicolor, 415 Irish moss, 466 INDEX 1063 Iron, 1003 — assay of in iron and quinin citrate, 1006 strychnin citrate, 1006 — estimation of, 1004, 1005, 1007 — organic compounds of, 1009 — peptonate and manganese, 1009 — peptonate, 1012 — reduced, assay, 1001 — salts, estimation of iron in, 1005 isocorybulbin, 238 Isoborneol isovalerate, 555 Isopilocarpin, 93 Isopral, 743 Isotrifolin, 430 Jaborandi, alkaloids of, 91 Jalap, 383 — assay, 49 — resin, examination of, 388 James's powder, 1001 Japaconitin, 268 Jervin, 278 Jesaconitin, 269 Jeteorrhiza calumba, alkaloids of, 229 Juglans cineraria, 357 Juniper communis, 789 Kaempferol, 370 Kalmia latifolia, 335 Kelene, 729 Ketones, general reactions, 599 — identification and determination in oils, 933 Kidney remedies, 788 Kola, analysis of, 298 — assay, 49 Kolatin, 298, 299 Kamala, 433 Krameria species, 427 Kresamine, 809 Kryofine, 867 Lactophenin, 868 Lactose, 617 — estimation of in infant foods, 619 Lactucarium. 501 Lactuca sativa, 502 — virosa, 501 Lactucerol, 502 Lactucin, 502 Lactucerin, 502 Lanthopin, 197 ! Lapaconitin, 270 Largin, 975 J Larix decidua, 486 I Laudanidin, 196 Laudanin, 195 Laudanosin, 196 Lead, 975 — acetate, 630, 975 — estimation of, 936 in Goulard's extract, 977 — monoxide, 975 — nitrate, 975 — oleate, 641, 975 — subacetate, 875 — sulphite, 975 — sulphocarbolate, 975 Lenirobin, 375 Lenigallol, 778 Leontin, 331 Leptandra, 443 Levulose, 617 Licorice, 407 — assay, 49 — paste, analysis of, 408 — powder, compound, 410 Limonene, 456 Liquidambar orientalis, 713 — styraciflua, 713 Listerine, 556 Lithium, 1025 — carbonate, 1025 — citrate, 1025 — estimation of, 1026, 1027, 1028 Lobelia, assay, 50 — inflata, alkaloids of, 96 Lobelin, 96 Lophophora alkaloids of, 307 — Williamsii, 307 — lewinii, 307 Lophophorin, 308 Loretin, 816 Losophan, 761 Luminal, 827 Lupetazin, 810 Lupulin, 424 Lyaconitin, 269 Lycetol, 810 Lysidine, 810 Macrotys, 339 Magnesium, 1021 — estimation of, 1022 1064 INDEX Magnesium, salts of, 1021 Malakin, 869 Malarin, 870 Malefern, 397 — assay of extract, 397 Mallotus phillipinensis, 433 Maltol, 777 Maltose, 617 — estimation of in infant foods, 619 Malubrin, 806 /-mandelonitrile glucoside, 341 — separation of, 342 Mandragora officinarum, alkaloids of, 100 Mandrake, 380 Manganese, 1014 — dioxide, 1014 — estimation of, 1014, 1015 — iodide, 1014 Manna, 551 Mannitol, 550 Maretin, 824 Marigold, 455 Martius yellow, 780 Matieo, 418 Meconidin, 196 Mentha pulegium, 615 Menthol, 556 — estimation of in oil of peppermint, 557 Menthone, 616 Menthyl chlormethyl ester, 558 — ethylgycolate, 558 — valerianate, 558 Mercaptans, 745 Mercuric bromide, 979 — chloride, 979 — cyanide, 979 — iodide, 979 — nitrate, 979 Mercurol, 726, 980 Mercurous chloride, 979 — iodide, 980 Mercury, 978 — and chalk, 978 — estimation of electrolytically, 983, 984 in ointments, 986 salts, 982 organic compounds, 988 soaps, 982 surgical dressings, 988 tablets, 984 — separation of from other metals, 988 — oxides, 978 Mercury, paraphenolsulphonate, 718 — salicyl arsenate, 883 Mescale, assay, 27 — button, 307 Mescalin, 307 Mesotan, 681 Methacetin, 854 Methoxyacetphenetidin, 867 Methylacetanilid, 851 — acetphenetidin, 867 — acetyl salicylate, 728 — aesculin, 343 — benzoyl salicylate, 728 — chavicol, 785 — chloride, 727 — coniin, 85 — cytisin, 330 — eugenol, 786 — gallate, 695, 728 — heptenone, 605 — hydrocotoin, 358 — iodide, 728 protocotoin, 358 — salicylate, 329, 681, 687 — assay of, 689 /3-Methyl-sesculetin, 341, 384 Methylal, 578, 728 Methylenedimethyl ester, 728 Methylene blue, 820 — creosote, 772 — diacetate, 578 — diantipyrin, 804 — dichloride, 729 — dicotoin, 729 Mitchella repens, 444 Microcidin, 784 Monochlorethylene chloride, 731 Monotal, 770 Moringa oleifera, 633 Morphin, 187 — colorimetric estimation of, 216 — estimation of in admixture with caffein, acetanilid, acetphenetidin and quinin, 218 — estimation of in Chinese pills, 215 laudanum, 213 paregoric, 211, 214 powdered opium, 211 syrups, 211 tablets, 214 Morphinmethylbromide, 191 Mother's cordials, 340 INDEX 1065 Mustard plaster, 347 Mustard seed, 347 assay, 51 Mydrol, 806 Myoctonin, 270 Myrrh, bisabol, 504, 505 — herabol, 503 Nandinin, 234 Nan-ta-yok, 715 Nargol, 726, 975 Naphthalene, 529 Narcein, 201 Narcotin, 198 Neoarsphenamine, 878 Neosalvarsan, 878 Neurodin, 825 Neuronal, 821 Nickel, 1002 — bromide, 1002 — estimation of, 1002 Nitrates, estimation of, 945 in meat extracts, 892 Nitrites, estimation of, 945 Nirvanin, 145 Nitrogen, 945 — estimation of, 888 Nitroglycerin, 736 Nitroglucose, 738 Non-volatile material, determination, 6 Nosophen, 667 Novargan, 974 Novaspirin, 680 Novatophan, 817 Novocain, 146 Nuclein, 724 Nucleoproteins, 895 Nux Vomica, alkaloids of, 250 assay, 51 Oil, anise, 928, 453 — apricot kernel, 923 — asafetida, 507 — ben, 623 — birch, 688 — bitter almond, 346 estimation of benzaldehyde in, 594 — caraway, 456, 930 — castor, 922 — cassia, estimation of cinnamic aldehyde in, 596 Oil, chaulmoogra, 924 — Cinnamonum species, 459 — clove, 457 — codliver, 919 — copaiba, 494 — coriander, 930 — cotton seed, 924 Halphen test, 915 — croton, 640, 923 — cubeb, 421 — estimation of unsaponifiable matter, 519 — eucalyptus, estimation of cineol in, 560, 561 — fennel, 456, 929 . — gaultheria, 688 — grindelia, 453 — haarlem, 488 — juniper berries, 798 — myrbane, 520 — nutmeg, 632 — olive, 922 — origanum vulgare, 766 — palm, 632 — peanut, 915, 933 — pennyroyal, 615 — peppermint, estimation of menthol in, 557 — pimento, 457 — Roman camomile, 553 — rue, 632 — sandal-wood, 930 — savin, 935 — sesame, 924 Baudoin test, 917 Villavecchia test, 917 — star anise, 928 — sweet almond, 923 — tansy, 615 — theobroma, 925 — thuja, 615 — turpentine, 486 — valerian, 448 — winter green, 688 Oils, fixed, 913 general methods for examination, 913 — volatile, 925 general methods for examination, 925 identification of in preparations, 931 Opium, 183 — alkaloids of, 183 1066 INDEX Opium, alkoloids of, identification and determination, 207 — assay, 53 — tincture of, assay, 59 Opopanax, 505 Orcinol, 776 Orexine, 818 Orizaba root, 386 Orthoform, 143 Orthoformic ether, 733 Ouabain, 314 Ovaferrin, 1010 Oxaphor, 612 Oxyacanthin, 234 Oxgall, 721, 723 Oxygen, 940 Oxynarcotin, 200 Oxyphenybenzylketone, 606 Padus virginiana, 340 Palmatisin, 270 Pancreatin, 902 — determination of milk curdling prop- erties, 905 — estimation of, 903 Pankreon, 699 Papain, 901 Para coto, 358 Paracotoin, 358 Paraiodanilin, 832 Paraiodophenol, 758 Parthenium integrifolium, 454 Paratophan, 817 Papaveramin, 195 Papaverin, 193 Paraformaldehyde, 575 Parahydroxyphenylethylamin, 301 Paratolyldimethylpyrazole, 805 Pareira brava, 305 Parillin, 327 Pearson's solution, 998 Peganum hamala, alkaloids of, 263 Pelletierin, 117 Pellotin, 308 Pennyroyal, 615 Pepsin, 896 — determination of in chewing gum, 513 proteolytic activity, 897 Petrolatum, 518 Peucedanum galbanifluum, 498 — rubricaule, 498 Pepper, oleoresin of, 88 Perborates, 968 — estimation of, 969 Permanganates, assay of, 1016 Peronin, 206 Peroxide, assay of metallic, 944 — benzoylacetyl, 569 — hydrogen, 941 — identification of in cold creams, etc, 944 — succinic, 569 Phenacetin, 854 Phenetidin salicylacetate, 869 Phenocoll, 867 Phenolphthalein, 666 — separation from anthraquinone drugs, 378 Phenols, 753 — identification and determination in oils, 932 Phenosal, 869 Phenyl-coumarin, 358 --- hydrazine, 791 — salicylate, 682, 683 — urethane, 824 Phenylenediamine, 819 Phesin, 868 Phloroglucinol, 778 Phosphates, estimation of, 960 Phosphoproteins, 895 Phosphorus, 956 — estimation of, 957 in galenicals, 958 rat paste, 957 Phosphotal, 772 Physostigma, assay, 60 — venenosum, alkaloids of, 302 Physostigmin, 303, 305 Physovenin, 304 Phytolacca, abyssinica, 427 — decandra, 426 Phytosterol, 917 Pichi, 441 Picradonidin, 339 Picraena excelsa, 356 Picrasmin, 357 Picratol, 757 Picrol, 775 Picropodophillin, 381 Picrotin, 400 Picrotoxin, 399 Picrotoxinin, 400 Pilocarpidin, 93 INDEX 1067 Pilocarpin, 92 Pilocarpus, alkaloids of, 91 — assay, 60 Pimento officinalis, 457 Pimpinella anisum, 455 Pinene, 486 — hydrochloride, 608 Pinus echinata, 486 — heterophylla, 486 — palustris, 486 — strobus, 414 — sylvestris, 486 — taeda, 486 Piperazine, 809 — quinate, 810 Piperidin, 88 Piperin, 87 Piper cubeba, 419 — species, 418 Piperonal, 599 Pipsissewa, 334, 335 Pistacia terebinthus, 486 Piturin, 99 Plasters, types of, 515 Pleurisy root, 438 Pneumin, 772 Podophyllin, 380 Podophyllum emodi, 381 — peltaltum, 380 Podophyllotoxin, 381 — estimation of, 382 Poke weed, 426 Pollantin, 396 Polychloral, 591 Polygala senega, 328, 687 Pomegranate bark, assay, 61 alkaloids of, 116 Populin, 336, 338 Populus alba, 336 — candicans, 336 — tremuloides, 336 Porphyrin, 181 Potassium acetate, 1023 — antimonyl tartrate, 649 — bichromate, 1012, 1024 — bitartrate, 648, 1024 — bromide, 1024 — carbonate, 1024 — chlorate, 953, 1024 — diiodoresorcinol monosulphonate, 775 — estimation of, 1026, 1027, 1028 — guaia^ol-sulphonate, 771 Potassium hypophosphite, 1024 — iodide, 1024 — nitrate, 1023 — and sodium tartrate, 1025 Pratensol, 430 Pratol, 429 Prickly ash, 431 Proferrin, 1011 Propazin, 143 Proponal, 826 Protan, 697 Protargol, 974 Protein, estimation of, 889 Proteins, 884 Protocotoin, 358 Protopin, 197 Protosal, 681 Protoveratridin, 279 Protoveratrin, 279 Prulauresin, 341, 343 Prunus lauro-cerasus, 341, 344 — serotina, 340 Pseudaconitin, 269 Pseudocinchona africana, 180 Pseudoconhydrin, 86 Pseudojervin, 279 Pseudomorphin, 192 Pseudopelletierin, 117 Psychotrin, 226 Pterocarpus marsupium, 484 Pulegone, 615 Pumpkin seed, 450 Punica granatum, alkaloids of, 116 Purpurin, 529 Pyoktanin blue, 853 — yellow, 853 Pyramidon, 794, 806 — acid camphorate, 807 — neutral camphorate, 807 — salicylate, 808 Pyrantin, 871 Pyridin, 811 Pyrogallol, 777 Pyrrole, 812 Quassia, 356 Quassin, 356 Quebrachamin, 180 Quebrachin, 180 Quercetin, 381, 429 Quillaja saponaria, 328 Quinamin, 165 1068 INDEX Quinaphthol, 177 Quince seed, 467 Quinicin, 167 Quinidin, 164 Quinin, 165 — eosolate, 177 — ethyl sulphate, 177 — lygosinate, 176 — phytin, 176 — separation from belladonna, alkaloids, 172 — salts of, 159 Quinoidin, 167, 815 Quinolin, 813 — bismuth sulphocyanate, 814 — chloridomethylchloride, 815 Rat powder, estimation of arsenic in, 999 — paste, estimation of phosphorus in, 957 Reagent, Froehde's, 1044 — Hager's, 1044 — Mandelin's, 1042 — Marine's, 1044 — Marquis', 1043 — Mayer's, 1044 — Millon's, 1044 — Scheibler's, 1044 — Sonnenschein's, 1044 — Wagner's, 1043 Rebaudin, 410 Red clover, 428 Remijia alkaloids, 165 Resaldol, 776 Resalgin, 804 Resopyrin, 805 Resorcinoform, 580 Resorcinol, 774 — hexamethylenetetramin, 776 — monoacetate, 775 — phthalein, 775 — salol, 776 Rhamnus californica, 372 — carniolica, 373 — cathartica, 373 — frangula, 373 — purshiana, 371 Rhatany, 427 Rhein, 366, 367, 368 Resin, acids, separation of from fatty, 480 — guaiacum, 482 — kino, 484 — thapsia, 485 Resins, 460, 481 — - acetyl value, estimation, 479 — analysis of, 474 — carbonyl value, estimation, 479 — classification of, 471 — constituents of, 471 — ester value, estimation, 477 — gum, 481 — methoxyl value, 479 — oleo, 481 Rheum officinale, 365 — palmatum, 365 — raponticum, 365 Rhubarb, 365 — assay, 62 Rochelle salt, 649 Rubber, 511 Rubijervin, 278 Rumex acetosella, 375 — crispus, 375 — obtusifolius, 375 Sabadilla seed, alkaloids of, 274 assay, 63 Sabadillin, 276 Sabadin, 276 Sabadinin, 276 Sabal serrulata, 415 Sabinol, 935 Saffron, 416 — American, 455 Sabromin, 633 Saccharin, 664 Safrol, 785, 935 Sagapenum, 510 Sajodin, 634 Salacetol, 604 Salicin, 336 Salicylamide, 821 Salicylparaphenetidin, 869 Salifebrin, 851 Saligallol, 778 Saligenin, 553, 787 Salicylic aldehyde, 596 Saliformin, 584 Salitannol, 683 Salithymol, 682 Salix alba, 336 — nigra, 336 Salol, 682, 683 Salophen, 682, 685 Saloquinin, 175 INDEX 1069 Salvarsan, 877 — estimation of arsenic in, 879 Sambucus nigra, 341 Sambunigrin, 341, 343 Sanguinaria, assay, 63 — canadensis, 244 Sanatogen, 895 Sanguinarin, 245 Sanoform, 679, 681 Santalyl carbonate, 735 Santonica, 392 — assay, 64 Santonin, 392 — estimation of in tablets, 394 santonica, 64 Santyl, 681 Saponaria officinalis, 329 Saponins, 325 — estimation of in emulsions, 334 — reactions of, 325, 332 — separation and identification of, 332 Sarcin, 295 Sarsaparilla, glucosides of, 327 — species, 326 — wild, 329 Sarsasaponin, 327 Saw palmetto, 315 Scammony, 385 — resin, examination, 388 Scilla maritima, 323 Sclererythrin, 302 Scopolamin, 109 Scopoletin, 241, 386 Scopolia atropoides, alkaloids of, 100 Scopolin, 111 Scullcap, 442 Scutellarein, 443 Scutellaria altissima, 443 — lateriflora, 442 Sedatin, 870 Sedative mixtures, 448 Seidlitz mixture, 648 Selenopyrin, 806 Semperviren, 241 Senecio aureus, 445 Senega snake-root, 328 Senegin, 329 Senna, 370 — estimation of in compound licorice powder, 410 Septentrionalin, 270 Serpentaria, 406 Seven barks, 427 Sidonal, 810 Silicates, estimation of, 965 Silver, 970 — colloidal, 972 — eosolate, 771 — estimation of, 971 — nitrate, 970 Simaruba officinalis, 357 Sinalbin, 347 Sinapin, 348 Sinapis alba seed, glucosides of, 347 Sinigrin, 348 Smilasaponin, 327 Smilax medica, 326 — officinalis, 326 — ornata, 326 — papyracea, 326 Snake root, black, 340 Canada, 406 Virginia, 406 Soap, 634 — assay of, 646 — bark, 326 — liniment, assay of, 636 Soap wort, 329 Sodium, 1022 — acid sulphanilate, 717 — anhydromethylene citrate, 657 — arsenoferri albuminate, 881 — arsenate, 875 — benzoate, 659 — betanaphtholate, 784 — bicarbonate, 1022, 1023 — bromide, 1022 — cacodylate, 874 — chloride, 1022 — estimation of, 1026, 1027 — ferrialbuminate, 1010 — glycerophosphate, 751 — hypophosphite, 1023 — lygosinate, 605 — metaoxycyanocinnamate, 669 — perborate, 966 — phosphate, 1023 — salicylate, 672, 677, 1023 — succinate, 647 — sulphite, 1026 — tetraborate, 966 Solidago species, 396 Somnos, 590 Sophol, 726, 974 1070 INDEX Sorbose, 617 Sozal, 718 Soziodol, 719 Spartein, 94 Specific gravity, 1 Spikenard, 329 Spirosal, 681 Squawroot, 445 Squawvine, 444 Squaw weed, 445 Squills, assay, 33 — glucosides of, 323 Starch, 617 Sterculia urens, gum of, 469, 470 Stillingia sylvatica, 432 Stone root, 442 Stramonium, assay, 67 Strontium, 1018 — salts of, 1018 — estimation of, 1018 Strophanthidin, 313 Strophanthin, 312 Strophanthus, assay, 67 — glucosides, 311 — gratus, 314 — kombe, 311 — hispidus, 313 Strychnin, 252 — estimation of in presence of quinin, 261 — determination of in chewing gum, 513 liquid products, 260 tablets, 259 — separation and identification, 258 of from atropin, 259 brucin, 259 Strychnos Nux Vomica, alkaloids of, 250 — ignatia, 250 Stovain, 146 Stylophorum diphyllum, alkaloids of, 244 Stylopin, 247 Styracin, 701 Styracol, 769 Styrax benzoin, 702 Subcutin, 144 Sublamine, 981 Sucrose, 617 — determination of, 7 — estimation of in infant foods, 619 Sulphonal, 746 Sugar, cane, estimation of in infant foods, 618 — determination, 7 Sugar, Munsen and Walker's tables, 10 Sulphates, estimation of, 956 Sulphonic acids, 717 Sulphopyrin, 805 Sulphur, 954 — determination of in asafetida oil, 508 — estimation of, 954 in compound licorice powder, 410 — iodide assay, 948 Sumbul, 435, 631 Suprarenin, 828 Swertia chirata, 351 Tannalbin, 697 Tannigen, 697 Tannismuth, 698 Tannoform, 698 Tannopin, 584, 698 Tanosal, 699, 772 Taraxacum officinale, 450 Taraxasterol, 450 Tartar emetic, 1000 estimation of in plasters, 489 Tea, estimation of caffein in, 289 Terebene, 527 Terpenes, 526 — sesqui, 526 Terpin hydrate, 559 Test, Baudoin, 917 — Borntrager's, 361 — Cripp's and Dymond's, 361 — Elaidin, 641 — Fluckiger's, 641 — Halphen's, 915 — Klunge's, 361 — Liebermann-Storch, 488 — Liebermann's, 753, 790 — Pettenkoffer's, 722 — Storch-Morawski, 488 — Villa vecchia, 917 Tetrahydroquinolin, 815 Tetraiodophenolphthalein, 667 Tetronal, 747 Thalline, 818 Thapsia garganica, 485 Thebain, 197 Theobromin, 291 — estimation of, 292, 293 Theophyllin, 294 Thermin, 811 Thermodin, 870 Thial, 585 INDEX 1071 Thioform, 679 Thioantipyrin, 805 Thiophene, 747 — dioxide, 748 — tetrabromide, 748 Thiosinamine, 823 Thiosulphates, estimation of, 956 Thuja occiden talis, 615 Thujone, 395, 615 Thymacetin, 868 Thyrnoform, 765 Thymol, 762 — carbonate, 765 — ■ estimation of, 763 — assay, 764 — iodide, 764 — salicylate, 765 Thiocol, 771 Toluifera periera, 705 — balsamum, 706 — pernifera, 706 Toluylenediamine, 820 Tolylantipyrin, 805 Tolypyrin, 794 Tolysal, 805 Tragacanth, 468 Trehalose, 617 Tribromphenol, 757 Trichlorethidene propenyl ether, 590 Trichlorisopropyl alcohol, 743 Trichlor-tertiary butyl alcohol, 147 Triferrin, 1011 Trifolianol, 429 Trifolin, 430 Trifolium incarnatum, 428, 431 — pratense, 428 Trigemin, 808 Triiodometacresol, 761 Trinitrophenol, 756 Trional, 747 Trioxybenzophenone, 606 Trioxymethylene, 575 Triphenin, 869 Trisulphoacetylguaiacol, 771 Triticum, 415 Tritopin, 196 Tropacocain, 123 Tropin, 111 Truxillin, 122 Tsuga canadensis, 486 Tumenol, 721 Turnera diffusa, 437 Turpentine, 486 — chian, 486, 488 — Russian, 486 — Venice, 486 Turpeth, 388 Tussol, 803 Tyramin, 301, 830 Umbelliferone, 435 Unicorn root, false, 331 true, 331 Urea, 822 Urethane, 824 Urginea maritima, 323 Uva-ursi, 334 Valeriana officinalis, 447, 631 ValidoL 558 Valyl, 822 Vanillin, 597 — estimation of, 598 Vellosin, 182 Veratralbin, 279 Veratridin, 276 Veratrin, 274 Veratrum album, 277 — assay, 68 — viride, 277 Veroform, 580 Veronal, 826 Veronica officinalis, 444 — virginica, 443 Verosterol, 444 Viburnum, 631 — compound, 331 — opulus, 445 — prunifolium, 446 Viferral, 592 Vioform, 816 Vitellin, 895, 896 Vouacapoua araroba, 374 Wahoo, 433 Witch hazel, 428 White pine, 414 Wild cherry bark, 340 Wormseed, American, 395 — Levant, 391 assay, 64 Wormwood, 391, 394 — Roman, 392, 396 1072 INDEX Xanthalin, 195 Xanthin, 285 — bases, determination, 286 — reactions of, 297 Xanthoeridol, 441 Xanthohumulol, 425 Xanthoxylum americanum, 431 — clava-herculis, 431 Xeroform, 757, 994 Yerba Santa, 438 Yohimbe Bark, alkaloids of, 178 Yohimbin, 178 Zimphen, 669 Zinc, 1016 — estimation of, 1017 — salts of, 1016 Zinzerone, 405 Zinziber officinale, 404 Zygadenin, 274 Zygadenus intermedium, alkaloids of, 274 Wiley Special Subject Catalogues For convenience a list of the Wiley Special Subject Catalogues, envelope size, has been printed. 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