Cornell lUnivetstti^ Xibrar^ OF THE mew l^orF? State College of Hgriculture A.^..'J:.66^.. , lMj.Mr/£ . gioi Cornell University Library RS 403.F85 The qualitative analysis of medicinal pr 3 1924 003 493 990 1. ^ Cornell University WM Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924003493990 THE QUALITATIVE ANALYSIS OF MEDICINAL PREPARATIONS BY H. C. FULLER, B.S. Chief Analyst, Institute of Industrial Research Washington, D. C. FIRST EDITION FIRST THOUSAND NEW YORK JOHN WILEY & SONS London: CHAPMAN & HALL, Limited 1912 Copyright 1912 By H. C. Fuller PRINTED BY THE PUBLISHERS PRINTING CO., NEW YORK, U.S.A. FOREWORD This book is offered with the hope that it will be of as much assistance to other workers in the field of drug chemistry as it has been in manuscript, form to my co-wofkers. There is a mass of material in the text-books and literature dealing with the analysis of medicines, but it is an almost hopeless task for one who is starting out with an analysis to examine it all, and pick out what he needs for his particular problem. The gathering and sifting out of data, experimenting with new reac- tions, and the evolution of new and satisfactory tests have occupied the greater part of the author's time dur- ing the past five years, and it has been the endeavor to arrange the results of these investigations in such a way as to evolve a scheme of analysis which will tell the worker what to do and how to do it, and, when he gets his reactions, enable him to interpret the results. Abundant use has been made of the material pre- sented in the literature, and many of the tests collected and described in Allen's "Commercial Organic Analy- sis" have been adopted. Full acknowledgment is made here to the authors of this work, and also to Dr. Ill IV FOREWORD F. B. Power and his associates, whose researches have cleared up so many disputed points, and whose results have been of much atssistance in compiling the accom- ig data. jLiiitnks are due to those of my co-workers who have experimented with the scheme of analysis, and whose desire to have the material as a permanent record has led the author to finally offer it for publication. CONTENTS PAGE Foreword, iii Introduction, v First Portion: Scheme of Analysis — Separation of Substances into Groups; Tests for Individuals I-78 Tables of Reactions of Anaesthetics and Opium Alkaloids, . 79 Second Portion: Methods of Analysis — Fluid Extracts and Tinctures, 81 Elixirs, Wines, Syrups, etc., 81 Emulsions, 87 Liniments, 88 Toothwashes and Gargles, 91 Solid Extracts, Powdered Extracts, and Concentrations, . 93 Pills, Tablets, etc., 95 Pastils 98 Powders, Cachets, and Hard Capsules, 99 Globules and Soft Capsules 99 Effervescent Preparations and Artificial Mineral Water Salts, 100 Pastes, Ointments and Emollients, loi Inhalants 105 Suppositories, Crayons, and Bougies, 105 Plasters, 106 Digestives, 108 Scheme of Analysis for Rapid Detection of Inhibited Drugs, no Reagents, 114 Index, 123 V INTRODUCTION During recent years the analysis of medicinal prepa- rations has become very important, and there have been evolved many new methods for determining the active ingredients contained therein, as well as new reactions for the identification of different substances. In the latter case, the tests almost invariably apply to the substances i^ question when they are alone and in the pure condition, and take no account of the influence which might be exerted on the reaction if other things were present, a condition usually obtaining in attempt- ing to identify the constituents of a complex medicine. Before one can, with any degree of certainty, proceed with the quantitative analysis, it is necessary to know the character of the components, and, up to the present, there has been no systematic scheme for obtaining this information. The Dragendorff and Stass-Otto methods of separation are satisfactory so far as they go, but they fall short of giving a complete analysis or separation of the manifold substances with which one has to deal when analyzing drug products. From the analysis of several hundred mixtures, a scheme of separation has been gradually evolved by which the different substances are obtained at certain stages of the manipulation, and their identity estab- lished with a few readily applied tests. A knowledge of the use to which a particular preparation is to be em- ployed is often a guide in arriving at conclusions as to its composition, and its price will often suggest what vii viii INTRODUCTION might not be present; in fact, a drug analyst can, with advantage, be more than a chemist pure and simple — - he should famiharize himself with the uses of the ordinary drugs, and have some idea of the current market conditions. It is not the intention of this work to describe in detail the chemical and physical properties of the substances involved; as such data are available, it would be super- fluous to repeat them here, and the laboratory should contain, for ready reference, the following, works : U. S. Pharmacopoeia; U. S. and National Dispensatories; " The Vegetable Alkaloids," Pictet & Biddle; " Plant Principles," Sohn; " Die Pflanzen Alkaloide," Briihl, Hjelt, and Aschan; " Die Glycoside," Van Rijn; " The Volatile Oils," Gildemeister and Hoffman; " Newer Remedies," Coblentz; Merck's Index; " Manual of Chemical Analysis," Newth. At times, the worker may meet with organic compounds which cannot be accounted for in this scheme, and for the possible identi- fication t)f such he should Tefer to " The Identification of Organic Substances," Mulliken. The work is divided in the following manner: The first portion describes the preliminary manipulation which separates the ingredients into large groups, then the scheme for separating these into smaller groups and individuals, and the tests for their identification; the second portion describes the methods to be employed in manipulating the various classes of medicinal prod- ucts to make them available to separation in accordance with this scheme. A diagrammatic arrangement, showing the essentials of the scheme at a glance, follows: INTRODUCTION ix go §•3*0 p '='P-S p n na ' P ta..!^ n) H w n > ^ m FT E — uScOni ^ •t &§ 2. "o S i=* -^S ?* s^cr.p' rtip p ^ d-.p^ "'gp > is-:. Pi I a m s H ." ." fS > 3iSf GSff"- ^M ^aB"5.hH 2--G2.0-QS.C/) 2hi B B. cio- BSO-^ i— T >am"'''> P^d So S Si:- hi Sx K P .. P* "-.as* " 2 >>,c 5 jJB P ">o^ ^7m age gE2. ff 'a.H..p— cum n ? B-!» £» S ft The Qualitative Analysis of MEDICINAL PREPARATIONS FIRST PORTION SCHEME OF ANALYSIS FOR THE SEPARATION AND DE- TECTION OF SUBSTANCES EST MEDICINAL PRODUCTS Treat the residue, or ground substance, with alcohol, 95 per cent., stirring thoroughly, warming if necessary to get the material into solution, decanting the filtered liquid if any remains undissolved. Repeat several times, if necessary. (a) Substances soluble in alcohol. Evaporate and treat the residue with water, filtering into a flask. Set aside one-third of the aqueous > solution, then treat the solution with dilute acid. (i) Substances soluble in water. Treat according to the scheme of separation described on page 12. (2) Substances insoluble in water. Treat as de- scribed on page 68. (b) ■ Substances insoluble in alcohol. Treat with water and filter. (3) Substances soluble in water. Treat as described on page 77. (4) Substances insoluble in water. Treat as de- scribed on page 78. 1 1 2 THE QUALITATIVE ANALYSIS OF By above process the substances mentioned below will have separated approximately into the respective groups : (l) SUBSTANCES SOLUBLE IN WATER Ammonium acetate Ammonium carbonate Calcium bromide Calcium chloride Gold chloride Iron chloride Mercuric chloride Mercuric cyanide Lithium bromide Potassium bromide Potassium thiosulphate Potassium iodide Potassium permanganate, decomposed by alcohol Silver nitrate Sodium acetate Sodium arsenate Sodium bisulphate Sodium bromide Sodium chlorate Sodium thiosulphate Sodium iodide Sodium nitrate Sodium nitrite, slightly sol. alcohol Sodium sulphite, spar. sol. alcohol Strontium bromide Strontium iodide MEDICINAL PREPARATIONS Zinc chloride Zinc bromide Zinc iodide Iron and quinine citrate Iron and strychnine citrate Lead acetate (partly sol. in alcohol) Lithium benzoate Lithium salicylate Potassium citrate (spar. sol. in alcohol) Soap Sodium benzoate Sodium salicylate Sodium sulphocarbolate Zinc valerate Chloral hydrated Guaiacol phosphate Sublamine AcetaniHde (somewhat sol. in H2O) Acetozone Adrenalin (sol. acids) Alphozone Acid salicylic Acid benzoic Add citric Acid tartaric Antipyrine Apiin Aristochin (sol. acids) Asaprol Benzacetin (Acetamido-methyl-salicylic acid) t THE QUALITATIVE ANALYSIS OF Benzoin (Phenylbenzoyl-carbinol^bitter-almond-oil camphor) Brometone, sol. H2O Bromural Catechu Chinaphenin (sol. acids) Chrysarobin (sol. H2O) Convallamarin Cotton-root bark resin Coriamyrtin Coronillin Coryfin Cyclamin Epicarin (somewhat sol. H2O) Emodin (sol. alkaline sol.) Eucalyptus gum — Red gum Esculin Ergotinin Eugenoform (diff. sol. alcohol) Eupatorin Euphorin — acids Euphthalmine — acids Formanilide Formicin GaDanol Gallicin Gallobromal Galloformin (difif. sol. in both H2O and alcohol) Gamboge (partly sol. in alcohol and H2O) Glycerin Glycosal Guaiamar MEDICINAL PREPARATIONS O Hedonal Ichthyol comps. (acids pptng. ichthyol) Isopral Kino Lactudn Lysidin Manna (from alcohol deposits mannite on cooling) Mesotan Musk (partly) Myrrh (partly) Novaspirin Novocain (sol. adds) Orthoform Oxaphor Oxgall, purified Periplocin Phenacetin (slightly sol. in H2O) Phloridzin Podophyllum resin (most of it is deposited by H2O on cooling) Resordnol Resorcylalgin Salophen Spirosal Tannosal Terpin hydrate Thiocol (si. sol. in alcohol) Thiosinamine Urethane Valyl Veronal THE QUALITATIVE ANALYSIS OF (2) SOLUBLE IN ALCOHOL AND INSOLUBLE IN WATER (E denotes the substances which may subsequently be removed by ether) Mercuric iodide (E) Phosphorus (E) Sulphur sublimed (E) Difluordiphenyl (E) Diiodoform Ethyl diiodosaKcylate (slightly sol. in water) Ethyl iodide Europhen Iodoform (E) lodoformal lodonaphthol Iron valerate (water decomposes it on boiling) Nosophen (Tetraiodophenolphtalein — iodophenin) (E) Orphol Sanoform (E) Terpene hydrochloride Thymol iodide (E) Tribromphenol (sol. ether) Tribromsalol (sol. ether) Triclilorophenol (sol. ether) Acids (Glycjn:rhizinic — ^precipitated by mineral acids) Acids: Cerotic, Benzoic, Oleic, Pahnitic, Salicylic, Stearic Alantol (E) Ammoniac (part sol. water; pt. E) MEDICINAL PREPARATIONS Amyl nitrite (almost insol. in water) Anemonin (sol. in CHCI3) Apiol (E) Arhovin (E) Asafetida (rmlky emulsion with water) Balsam Peru (E, partly) Balsam Tolu (E, partly) Benzoin Benzyl cinnamate — Cinnamein Benzosol — Guaiacol benzoate (E) Betanaphthol salicylate (E) Burgundy Pitch (E) Bromoform (E) Camphor monobromated (almost insol. in water) (E) Cannabinon Cardol Cascarilla resin Chlorophyll (E) Chrysarobin (E) Cantharidin Cimicifuga resin (E partly) Cinnamyl cinnamate (Styracin) Cocain carbolate Colophony (E) Convallarin Copaiba (E) Creosote carbonate (E) Cresalol (Cresol sahcylate, E) Damiana resin (E) Eriodictyon resin (Yerba santa) Eupyrin (sol. ether) Filmaron (difficul. sol. alcoh., E) 8 THE QUALITATIVE ANALYSIS OF Fluorescin Fortoin (spar. sol. alcoh. & sol. alkalies, E) Formopyrin (almost insol. alcoh.) Formylphenetidin (sol. in hot water; E) Galbanum (emulsifies with water; E) Gallogen (insol. acids) Grindelia robusta resin (E) Gamboge (part. sol. alcohol; E por.) Guaethol — Guaiacol ethyl Guaiac (E partly) Guaiacol carbonate — Ductal (sol. ether; E) Guaiacol salicylate (E) Hypnoacetin latrol lothion (E) Kamala (part. sol. alcohol; E) Kamahn Kosin(E) Koussein Losophen Mastic (E) Methylene diguaiacol — Geoform Monotal Naphthalene (E) Naphthol (i-iooo in water; E) Paraffin (E) Phenacetin Phenolphthalein (E) Protosal (E) Resin jalap (E partly) Resin podophyllum Resin scammony (E) MEDICINAL PREPARATIONS 9 Salitannol Sapogenin Salit (E) Salol (only very slight sol. H2O; E) Santonin (only very slight sol. HaOj E) Salacetol (only very slight sol. H2O; E) Scutellarin Skatol (sol. hot water) Storax (E partly) Styracol — Guaiacol dnnamate Sulphaminol Styrene — ^Phenylelthylene (constit. of storax — sol. ether) Tar (E) Tannoform Taraxacum resin Tannopin Trioxjonethylene (si. sol. H2O) Triphenin Turpentine (E) Validol — Menthol valerate (oil; E) Valerydin — Sedatin Wax (E) Yerba Santa resin (3) INSOLUBLE IN ALCOHOL BUT SOLUBLE IN WATER Arsenous acid Aluminum and potassium sulphate Ammonium bicarbonate Ammonium chloride (si. sol. alcohol) Ammonium phosphate 10 THE QUALITATIVE ANALYSIS OF Antimony and potassium tartrate Calcium thiosulphate Iron pyrophosphate Lithium carbonate Potassium carbonate Calcium hypophosphite Potassium nitrate Sodium bicarbonate Sodium biborate Sodium carbonate Sodium chloride (si. sol. alcohol) Sodium hypophosphite Sodium phosphate Sodium pyrophosphate Sodium sulphate Zinc sulphate Iron citrate Iron and ammonium citrate Iron and ammonium tartrate Iron and potassiimi tartrate Lithium citrate Potassium bitartrate (sparingly in alcohol) Potassium and sodium tartrate Mercurol Enesol (Mercury salicylarsenate) Ferrostyptin (insol. cold alcohol) Acacia Citarin Creatin Erythrol (sol. alcohol) MEDICINAL PEEPARATIONS 11 Euqmnin (sol. adds) Gluconic acid Hirudin Papain Pancreatin Pepsin Quininephytin (Quinine anhydro-oxymethylenediphos- phate) Saloquinine (sol. acids) Sugar Sulphanilic acid Thiocol Triox5Tnethylene (4) INSOLUBLE IN ALCOHOL AND WATER Bismuth subnitrate Ammoniated mercury Cerium oxalate Mercurous iodide Mercurous oxide Mercuric oxide (very si. sol. H2O) Mercurous chloride Sulphur precipitated Zinc carbonate Zinc oxide Zinc phosphide Airol (Bismuth beta-oxyiodogallate) Bismuth citrate Bismuth subgallate Crurin (Quinolin-bismuth sulphocyanate) 12 THE QUALITATIVE ANALYSIS OF Cutal (Aluminum borotamiate) Dermol (Bismuth chrysophanate) Ferratin lodalbin (almost insoluble) lodol Sajodin (Calcium iodobehenate) Triferrin (Iron paranucleinate) Cantharidin (sol. hot alcohol; but deposits on cooling) Gurjun balsam (part. sol. alcohol) Lard Starch Spermaceti (sol. in hot alcohol; but deposits on cooling) Tannalbin (sol. in alkahes) Xeroform Now proceed with the examination of No. i, accord- ing to the following scheme of separation. It will be noted that the tables which foUow, include some of the substances which were reported as being insoluble in water, but as the scheme is adapted to the procedures for examining the different classes of galenical products, the manipulation of which is detailed in the second sec- tion of the work, it is necessary to make provision for their occurrence. (l) SUBSTANCES SOLUBLE IN WATER Acid Solution Note whether the solution is fluorescent. Pichi, pink florescence with acids. Quinin, blue florescence. MEDICINAL PREPARATIONS 13 Sanguinarin gives a red solution without fluorescence. Shake out three times with petroleum ether, sepa- rate the solvent, wash it with water, and filter into a small beaker and evaporate over the steam-bath. Alkaloids Bitter Principles Acids Piperin r.S''-^.," f Ab^^ 1—5= f Sl!f ,^^^ Narcyl slightly "! Capsacem { ^.. ;„ ,„o Hop Bitter Acetanilide 113° Phenacetin (small amounts) I28°-I29° Antipyrine (traces) II2°-II3° Siibcutin (somewhat) I95°-I96° Chloretone 8o°-8i° Brometone Epicarin (partly) I95°-I99° Chloral hydrated 58° Neuronal 66°-67° Sulphonal I25°-I26° Trional 76° Veronal (slightly) 191° Dormiol I Cinnamic 135° [ Picric (very slightly) Cresol Thymol 50°-5l° Menthol 243° Camphor 175° Terebene B-ieo'-lSo" Copaiba Cubebin 125° Santalol Cumarin 67° Vanillin 8o°-8i° Styrone (Cinnamic Alcohol) Odor of hyacinth. B-250° Note the odor: Camphor, menthol, copaiba, styrone, thymol, terebene, cubebol, santalol, coumarin, and vanillin have characteristic odors. It should be noted, how- ever, that most of these substances are but slightly soluble in water, and the first eight will appear in largest amount in the residue from the alcoholic extract, which is insoluble in water. 14 THE QUALITATIVE ANALYSIS OF Remove a small quantity on the end of a glass rod or on the end of the finger, and touch the tongue. Pungent sensation indicates capsacein, piperin. Bitter taste indicates hop bitter, absinthin Peppery sensation indicates chloretone brometone. Numbness indicates subcutin. If the residue is in considerable quantity, dissolve a portion in P.E.,* transfer to another dish, and evaporate. Cover the dish with a watch-glass, and place on a cov- ered water-bath. Note any subHmate that collects on the watch-glass, indicating acetanilide, benzoic and sali- cylic acids. Salicylic acid sublimes more slowly than benzoic, and collects in quantity on the sides of the flask; benzoic collects in long stalactites having a brilliant lustre. Cinnamic acid does not sublime. Treat a portion of the subKmate with water, pour into an evaporating dish, and add a drop of ferric chloride solution; a purple color indicates presence of salicyHc acid. Treat a portion of sublimate or the material on the bottom of the dish with 5 c.c. chloroform and 2 c.c. of concentrated potassium hydroxide, heat carefully, note odor, the presence of acetanilide being indicated by the evolution of phenyl isocyanide. Treat a portion of residue with dilute hydrochloric acid and water, placing a few drops on a water-glass, and adding Mayer's reagent; if a precipitate is obtained, antipyrine is indicated. To another portion of this solu- tion add a few drops of potassium bromide-bromate re- agent; if a blue color appears, phenacetin is indicated. * This abbreviation denotes petroleum ether. MEDICINAL PREPARATIONS 15 Treat a portion of the residue with 2 to 3 c.c. of cold 10 per cent, potassium permanganate solution, and warm slightly; if the odor of benzaldehyde develops, cinnamic acid is indicated. Treat a portion of the residue with hot water, cool, filter, and treat with a few drops of ferric chloride; in the presence of epicarin an intense blue color de- velops. In making this test, the analyst must take into account whether or not salicyHc acid had been pre- viously indicated, or whether vanillin had been noted by the odor. Treat a portion of residue with concentrated sul- phuric add; an orange-red color indicates piperin. This test cannot be depended upon unless the residue is white. Piperin should be crystallized out in P. E., and its melting-point determined — 128° to 129°. Treat a portion of the aqueous solution with ammoni- acal silver nitrate, and warm. A reduction indicates chloral or dormiol. Treat a portion of the residue with ammonium vana- date; a green color, changing to blue, quickly disappear- ing, indicates subcutin. Treat another portion with for- maldehyde-sulphuric acid, which gives, with subcutin, a salmon color changing to brown. Usually one is able to obtain sufl&cient of the crystal- lizable substances in the pure state to determine the melting-point, and when this figure is found, and cor- roborated by its characteristic reactions, the identity is estabHshed. Benzoic acid may be separated from salicylic by dis- solving both in dilute hydrochloric acid, adding excess of bromine water which precipitates the salicyhc acid. 16 THE QUALITATIVE ANALYSIS OF filtering, boiling off the excess of bromine, and shaking out the benzoic acid with ether or P. E. Coumarin and vanillin may be separated by dis- solving in ether, and shaking out with dilute ammonia, which will completely remove the vanillin. The ether is then evaporated, and the coumarin identified by its melting-point. The ammoniacal solution is then acidi- fied, shaken out with P. E., separated, and the solvent evaporated, which leaves the vanillin in a form which can be readily identified. Sulphonal, trional, and neuronal are best identified by their melting-points. A solution of pyrogallol in pure 66 per cent. H2SO4 gives a blue color when gently warmed with Moral, a ruby color with butylcMoral, 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. Shake out three times with ether, separate the solvent, wash it with water, filter into a small beaker, and evap- orate over the steam-bath. Acids* Atropic io6°-io7° Camphoric 187° Catechutannic CholaKc Creosotic, ortho 163°, meta 174°, para 151° Diiodosalicylic 220°-23o° Formic * The italics are used to call attention to the commoner substances. MEDICINAL PREPARATIONS 17 Gallic 22o°-240° Gelsemic i63°-i97° (?) Laurie 43° Lactic Meconic Monobrombenzoic, para 251° MonoiodosaUcylic 198° Nitrobenzoic, ortho 147°, para 238°, meta 148° Oenanthic io°-ii° Oxybenzoic, meta 200°, para 210° Protocatechuic i99°-2cx)° Succinic 182° Tannic acid slightly Tropic ii7°-ii8° Valeric Veratric 182° Gltjcosides Anthemin Asclepiadin CoUinsonin Convallamarin slightly EuonjTnin slightly Helleborin Hydrangin Rutin Scutellarin * The italics are used to call attention to the commoner substances. 18 the qualitative analysis of Alkaloids Caffein, slightly, 236° Colchicin Narcotin, slightly, 171° Theobromin 329°-330° Narcyl, slightly Anesthetics Anesthesin, partly, 89°-9i° Orthoform, trace, i4i°-i43° Propaesin 74°-76° Subcutin i95°-i96° Plant Principles Not Glucosides or of Un- known Composition * Arnica principle Chiratin Cnicin, slightly Chrysarobin, partly Colocynth bitter Columbin, traces Cotoin Cotton-root resin Elaterin, slightly Emodin Gentiopicrin, slightly * The italics are used to call attention to the commoner substances. MEDICINAL PREPARATIONS 19 Ginger resins Helenin Hop resins Lactucerin Meconin 102° Picrotoxin 192° Podophyllotoxin Santonin, partly 170°-! 71° Acetanilide 113° Acetozone 37° (?) Alphozone Antipyrine ii2°-ii3° Aspirin 135° Bromacetanilide, para (Asepsin) 164° Colchicein 149°-! 51° Coryfin Epicarin ig5°-igg° Ethylacetanilide 50° Gallanol (GalKc acid anilide) 205° Gallicin (GalKc acid methyl ester) 202° Helio tropin 37° Phenacetin i34°-i35° Saccharin 220° Saligenin (Diathesin) 86° Salophen i87°-i88° Sapogenins Sucrol (Dulcin) 173°-! 74° Thymacetin 136° Trioxymethylene 171° Valyl (Valeric acid diethylamide) * The italics are used to call attention to the commoner substances. 20 the quautative analysis of Hypnotics * Hydrated Choral Bromal Hydrate 53° Butyl Chloral Hydrate 78° Dormiol Chloral formamide 114°-! 15° ChloraUmide 155° Chloralose 185° Chloral ur ethane 103° Euphorin (Phenyl urethane) 49°-5o° Neuronal 66°-6'j° Veronal 191° Propanol Proponal 145° Tetronal 85° Trional 76° Sulphonal 125°-! 26° Methaform Hedonal 76° Hypnone 14° Urethane 48^-50° Ethyhdeneurethane i25°-i26° Bromural Phenol' and Phenol Derivatives * Phenol 40° Picric acid i22°-i25° Pyrogallol 132 * The italics are used to call attention to the commoner substances. MEDICINAL PREPARATIONS 21 Methyl eugenol Betanaphthol 122° Creosote Creosote phosphite (Phosphotal) Creosote valerate (Eosote) Fluorescein Hydroquinon 169° Phenolphthalein 250** Phloroglucinol 20o°-209° Pyrocatechin 104 Resorcinol 109°-! 11° Cantharidin 218° Cholesterin i4S°-i48° Coumarin 67° Ichthyol Lecithin VaniUin 8o°-8i° Certain substances which are present in the petroleum ether fraction wiU appear now, being incompletely re- moved by that solvent. Thus, if salicylic acid, anti- pyrine, acetanihde, neuronal, veronal, trional, sulphonal, and phenacetin were found in the residue left on evap- orating petroleum ether, they will be found here. Note the color. If yeUow, draw off 2 c.c. into a test- tube, add I c.c. ammonia, and shake. If the ammonia turns pink or crimson, emodin or phenolphthalein is indicated. A pinkish-yellow color, gradually deepening with a more pronounced pink shade, will be observed if * The italics are used to call attention to the commoner substances. 22 THE QUALITATIVE ANALYSIS OF aloes are present, this conclusion being further strength- ened hy a pronounced odor of aloes in the original mate- rial. A green fluorescence denotes the presence of gel- semic acid or esculin. Evaporate the entire ether solution over the steam- bath, using a fan as the last portion evaporates, to pre- vent overheating, and note the quantity of the residue. Note whether there are needle-like crystals present, characteristic of caffein and theobromin. Note the odor, which will indicate the presence of ginger resins, phenol, guaiacol, ichthyol, vanillin, and coumarin. Dissolve the last residue in ether, evaporate about ten drops, and test the residue cautiously by removing a small portion on the end of a rod or the finger. An intense sweet taste indicates saccharin. A numbness produced on rubbing the end of the tongue indicates propaesin, subcutin, and anesthesin. Note whether the residue has a bitter taste. Remove five to ten drops onto a watch-glass, and evaporate. Treat residue with 2 c.c. dilute sulphuric acid, and warm; if the material does not completely dissolve, filter into another watch-glass. Add Mayer's reagent; a precipitate indicates antipyrine, colchicin, narcotin, the precipitate of colchicin being a deep yellow color. Remove another five to ten drops, and evaporate in a porcelain evaporating-dish. Add one to two drops of concentrated sulphuric acid, and note the color. Emedin, pink. Elaterin, pink quickly changing to reddish-yellow. Picrotoxin, yellow, orange, red on warming, and grad- ually a reddish-brown, while the solution becomes MEDICINAL PREPARATIONS 23 fluorescent, observable on pouring the solution into a small test-tube. Colocynth bitter, yellow-brown. Cotoin crystals turn orange, while solution becomes bright yellow. Meconin, pale yellow gradually becoming pale violet. Convallamarin, brown, becoming deep purple on standing. Santonin, yeUow, with violet around isolated crystals. Gentiopicrin, colorless, carmine on warming. Gelsemic acid, yellow. Narcotin, pale yellow, pink on edges, gradually red develops all through. Many other substances give a brownish or a greenish- brown color, which is not characteristic. Next remove five to ten drops, evaporate in a por- celain dish, and add one to two drops of Froehde's reagent. Colocynth bitter gives a dirty red, red, cherry-red. Elaterin, pink, yellowish-green, deep green. Emodin, pink to red-pink. Hydrastin, deep green. Meconin, pale yellow, pale green. Narcotin, deep green. None of the other plant principles give characteristic colors. Next remove five to ten drops, evaporate in a porce- lain dish, and add one to two drops of ammonium vana- date reagent. Meconic acid, purple, deep blue; gradually fades, very characteristic. 24 THE QUALITATIVE ANALYSIS OF Colocynth hitter, red, blue in thin layers, pink, grad- ually deep crimson. Elaterin, intense blue, soon fading to dirty yellow; undissolved crystals, orange, finally deep green, very characteristic. Emodin, bright red, liquid soon turns brown. Phenolphthalein, deep orange, pink on edges. Meconin, crystals pale yellow at moment of solution; solution turns pale green, yellow, gradually pale red. Subcutin, green to blue, disappearing quickly. Santonin, no color. Narcotin, brick red, pink in thin layers. Propaesin, purple gradually fading to brown and gray. Remove five to ten drops, evaporate in a porcelain dish, treat residue with two c.c. water, warm, then cool, and add two to five drops ferric-chloride test solution. Green or greenish-black color indicates tannins. Meconic acid, deep red. Cotoin, violet-brown. Aspirin, violet. Phenol, blue. Epicarin, blue. Salicylic acid, violet. Pyrogallol, orange-yellow. Guaiacol, red, orange-red, slowly fading, and solution becoming turbid. Hydroquinone, yellow-orange, green-black precipitate. PMoroglucinol, blue-violet, violet fading rapidly. Resorcinol, blue-violet. Vanillin, blue. Coumarin, no color. MEDICINAL PREPARATIONS 25 Remove five to ten drops, evaporate in porcelain dish, add one to two drops concentrated nitric acid, and note reaction. Then evaporate and add alcoholic KOH. Cotoin with HNO3, deep blue, black, considerable action, brown-orange; very characteristic. Santonin, no characteristic reaction with HNO3, on evaporation and addition of ale. KOH, orange. Asclepiadin with HNO3, pink to purple. Elaterin chars on adding HNO3. Subcutin on adding ale. KOH gives blood-red color and a fragrant odor. Colchicin, blue. Gelsemic acid, yellow, orange; add ammonia, which produces a blood-red color, very permanent. Lead acetate gives ppts. with tannin, meconic acid. If phenolic compoimds are indicated (color reaction with FeCls) evaporate five c.c. of the ether solution in a test-tube, and fuse with NaOH and phthaMc acid, cool residue, and add water. Phenol gives phenolphthalein. Guaiacol gives a solution violet-blue and violet. Resorcinol gives fluorescin. If sufficient material is present it should be purified by crystallizing out of water, alcohol, or other solvent, dried carefully, and melting-point determined. If this scheme does not serve to identify the substances present, proceed according to MuUiken's scheme for the identification of organic bodies. If saccharin is indicated by the sweet taste, and the residue gives a blue color with FeCU indicating salicylic acid or other substances, treat a portion with dilute hy- drochloric acid, warm, filter, cool, and add bromine 26 THE QUALITATIVE ANALYSIS OF water, allow the ppt. to settle, then filter and wash. Boil filtrate until bromine is expelled, add a small piece of NaOH, evaporate the solution, fuse in an oil-bath to 250° C, cool, add water, and transfer to separator, add HCl and shake out with ether, evaporate ether, test residue with FeCls, when a violet color, due to formation of salicylic acid from saccharin, will be observed. Dulcin may be differentiated from saccharin by dis- solving in ether and shaking with alkaH, which removes the saccharin; the ether is then washed, filtered, and evaporated, leaving the dulcin. Test for cantharidin by dissolving a portion in alcohol and applying the solution to the arm, which will blister if this substance is present. Santonin gives a red color with warm alcoholic KOH. Anesthesin, subcutin, propaesin, anesthetic derivatives of amidobenzoic acid, all appear at this point. Subcutin gives salmon gradually to brown with formal- dehyde-sulphuric acid reagent, and green to blue color with ammonium vanadate. Propaesin gives, with ammonium vanadate, a purple gradually fading to brown and gray. Propaesin may be hydrolyzed by boiling with NaOH under a reflux; propyl alcohol is one of the products, and will be apparent because of its odor; from the alkaHne solution mineral acids will precipitate the acid radicle. Anesthesin does not give these reactions. Aspirin differs from salicylic acid in giving no precipi- tate with bromine water. Emodin dyes wool yellow; the color is stripped by ammonia, and gives a second dyeing. An alcoholic solution of emodin on evaporation with FeCls leaves a MEDICINAL PREPARATIONS 27 yellow residue; phenolphthalein under similar conditions leaves a pinkish residue, with odor of phenol, the color disappearing on cooUng to moisture. Phenolphthalein goes on to wool, but there is no color imparted. Veronal, sulphonal, trional, and aspirin give no imme- diate precipitates with iodine or picric acid, though with the latter reagent crystals will sometimes form on long standing. Veronal sublimes on heating. If i to 2 c.c. of a satu- rated aqueous solution are treated with two drops nitric acid, and then with a few drops of Millon's reagent, a gelatinous white precipitate is obtained. When added to potassium hydroxide fused in a nickel crucible, and heated for two minutes, the cold mass, on dissolving in water, should give the Prussian-blue test with ferrous sulphate; on adding excess of acid, and shaking out with ether, an oily mass is extracted having the odor of rancid butter, soluble in water, the solution giving a wine-red color with ferric chloride. Elaterin on fractionation yields a dextro- and levo- body or groups of bodies, the former being inert, the latter purgative. Scutellarin, when treated with water and sulphuric acid, is dissolved with the formation of scuteUarein, CisHioOs, and glucuronic acid; on pouring the solution into considerable water the former is precipitated. ScuteUarein dyes wool reddish-brown with chrome mor- dant, brownish-yellow with aluminum, lemon with tin, and olive with iron. The hydrobromide, hydrochloride, and sulphate are intensely colored. Glucuronic acid in dilute alcohol gives a green color when treated with alphanaphthol and concentrated sulphuric acid; with 28 THE QUALITATIVE ANALYSIS OF more water the color changes through blue to violet, and even red, the green color being regenerated by adding concentrated sulphuric acid. Scutellarin gives an orange-yellow barium salt. Now shake out the acid solution three times with chloroform, when the following substances, if present, will go into solution. Alkaloids * Berberin traces Caffein 236° Colchicin ' Geissospermin 160° Hydrastin, partly 132° Narcein, partly 145° Narcyl base (Ethylnarcein) Narcotin 171° Oxyacanthin 210° Papaverin 147° Piperin 130° Quebrachin 2i4°-2i6° Theobromin 329°-330° Glucosides and Plant Principles other than Alkaloids * Adonidin Anthemin Columbin * The italics are sued to call attention to the commoner substances. MEDICINAL PREPAILA.TIONS 29 Cedrin Condurangin Daphnin Digitoxin 240° Elaterin Gitalin 150°-! 55° Emodin, somewhat Helleborin Menyanthin, glucoside from buckbean Methylene Blue, very slightly Betanaphthol benzoate 110° Hippol (Methylenehippuric add) 151° Aniipyrine 112°- 113° Phenacetin i34°-i35° Santoninic acid Ox)aiaphtoic acid, alpha 186°, beta 156° Physalin, from Physalis Alkekenga Picrotoxin 192° Piscidin Quassin Senegin, slightly Polygalic acid, slightly Strophanthin, slightly Santonin i7o°-i7i° Strophanthidin Evaporate the chloroform solution cautiously over the steam-bath, using fan, and note the appearance of the residue. * The italics are used to call attention to the commoner substances. 30 THE QTJALITATI\-E ANALYSIS OF Methylene blue gives a blue color. Berberin and colchicin give a yellow residue (the latter will have been indicated in the ether fraction). Caffein and theobromin give needle-like crystals. Taste residue, and note whether it is bitter, indicating quassin and chrysarobin. Dissolve the residue in a small amount of chloroform, evaporate five to ten drops on a watch-glass, dissolve residue in one to two c.c. dilute sulphuric acid, and add Mayer's reagent; a precipitate indicates the presence of some alkaloid, but not caffein or theobromin. If no precipitate occurs, add one c.c. solution of iodine and potassium iodide; a precipitate indicates caffein, ^theo- bromin, and possibly other substances. If caffein was present in the original material, it would have been found to some extent in the ether fraction, unless it was present in very small amounts only. Antipyrine would have been preAdously indicated; piperin would have been found before, as weU as chrysarobin, elaterin, emodin, picrotoxin, and santonin. Evaporate five to ten drops of chloroform solution in a porcelain evaporating-dish, cool, add one to two drops concentrated sulphuric acid, and observe the color. Narcein, deep brown at moment of solution, then yellow, gradually becoming green, and finally blue. Narcotin, pale yeUow, gradually pink on edges, and gradually a red color develops through the mixture. Papaverin, pale, violet, soon fading. MEDICINAL PREPARATIONS 31 Quebrachin, blue c«lor gradually develops, brought out more intensely by addition of lead peroxide or K2Cr207 (in the latter case the mixture soon turns brown). Geissospermin, blue. ColumUn, orange changing to deep red. Hydrastin gives a faint yellow, deep purple on heating. If a trace of HNO3 is present, a yellow color is pro- duced, and with a larger proportion the color is orange-red. Ckrysarobin, deep red. Digitalis glucoside, red, more intense on warming; expose to fumes of bromine and a violet color appears. Elaterin, pink quickly changing to reddish-yellow. Emodin, pink. Picrotoxin (see ether fraction). Quassin, no characteristic color. Strophanthin, green, greenish-yellow, brownish-green, finally dirty brown; warmed to 50° to 60°, the green color changes to dark olive, dark brown, violet, dark violet-blue, black with violet tint. Not a common substance, and not removed to any great extent by CHCI3, most of it remaining in the aqueous solution after the treatment with immis- cible solvents. Santonin, yellow, violet aroimd isolated crystals. Saponin, yellow, violet shade gradually appears. Polygalic acid, reddish yellow, gradually red, deep red, and, on warming, dark violet. Evaporate five to ten drops of the CHCI3 solution, 32 THE QUALITATIVE ANALYSIS OF as before, and treat the residue with one to two drops Froehde's reagent. Narcein, greenish-brown. Narcotin, deep green; characteristic. Hydrastin, sage-green. Papaverin, purple, gradually blue. Oxyacanthin, violet changing to yellowish-green on edges. Saponin, dirty yellow, violet shade develops on edges, changing to indigo blue. ColcMcin, yellow. Tests of the other substances which were also re- moved partially by ether, will not be repeated here. Evaporate five to ten drops of the CHCI3 solvent, as before, and treat the residue with one to two drops of ammonium vanadate. Narcotin, brick-red, pink in thin layers. Narcein, reddish-brown. Papaverin, purple, blue, green, gradually deep blue; characteristic. Colchicin, yeUowish-green. Hydrastin, pink, bright red, gradually brick-red. Saponin, violet, purplish-brown; indigo-blue on edges. Oxyacanthin, dirty violet to reddish-violet. Evaporate five to ten drops of CHCI3 solution, as before, and treat the residue with one to two drops foirmaldehyde-sulphuric acid. Narcotin, purple to slaty, soon fading. MEDICINAL PREPARATIONS 33 Narcein, deep brown, green on edges, gradually deepening. Papaverin, purple, violet, crimson; characteristic. Colchicin, crystals reddish, liquid yellow. Eydrastin, no reaction. Evaporate five to ten drops of CHCI3 solution, as before, and treat the residue witii one to two drops nitric acid. Narcotin, deep yellow. Narcein, yellow fading. Papaverin, yellow. Colchicin, deep purple; characteristic. Eydrastin, yellow. Geissospermin, purple-red, disappears on heating. Polygalic acid, ruby-red; on adding more HNO3 the color becomes brighter, until finally bright yellow. Perform murexide test for caffein and theobromin. To purify these substances if it is desired to take a melting-point, dissolve in dilute hydrochloric acid, and precipitate with iodine in KI, filter, decompose preci- pitate with H2SO3, shake out with CHCI3 after adding NH4OH, and determine melting-point of residue. If other alkaloids are present, first precipitate the acid solution with Mayer's reagent, filter, and then add iodine solution to precipitate caffein. Quassin. Allen's test. Dissolve in CHCI3, shake with Br-water in excess, separate CHCla'and shake it with NH4OH. The color due to Br is immediately de- stroyed, and if quassin be absent both the CHCI3 and NH4OH will be colorless; in presence of quassin, the 3 34 THE QUALITATIVE ANALYSIS OF NH4OH will be colored bright yellow. Substances from Calumba, Colocynth, Cocculus Indicus, and Chiretta do not give any similar reaction. If picric acid is present, it may be removed by shaking the CHCI3 solution with NaOH before adding Br-water. Chrysarobin. Add dilute or cone. KOH, which forms a red liquid with a green fluorescence. Fuming HNO3 gives a red-colored mixture, turning violet on addition of NH4OH. On shaking with lime-water, it gives a violet-colored Mquid. Chrysophanic acid gives a yellow liquid in both latter tests. Sydrastin. A solution of the residue in dilute acid gives a precipitate with K2Cr207, which, on separating, gives a bright red color when moistened with H2SO4. A solution of hydrastin in dilute H2SO4 should be treated with a drop of KMn04. The color of the reagent is immediately discharged, and an intense blue fluor- escence develops. Additional reaction for hydrastin, hydrastinin, and narcotin. A solution of hydrastin i : 300 in alcohol, of hydrastinin i : 100 in alcohol, and of narcotin i : 100, in dilute sulphuric acid and o.i c.c. added to 2 c.c. con- centrated sulphuric acid will give the following color re- actions: With 0.1 c.c. gallic acid i : 20 green to blue; with guaiacol or catechol i : 20, red tint changing to violet on warming; with morphin, violet. If hydrastin or narcotin be oxidized by acid solution of permanganate, opianic acid is produced, and on adding alcohol until a I per cent, solution is obtained, and then treating o.i c.c. of this solution with 2 c.c. concentrated sulphuric acid, the following reactions will take place: With o.i c.c. MEDICINAL PREPARATIONS 35 gallic acid a blue color, fading to brown on warming; with guaiacol, red becoming intense blue on warming; with alphanaphthol, gooseberry-red; with betanaphthol, wine-red; with codein in alcohol i : 20, violet turning blue on warming. Hydrastinin hydrochloride solution blackens instantly with Nessler's reagent. Morphin, apomorphin, and picrotoxia precipitate mercury from the reagent. Gitalin is a new glucoside from digitalis, and is the chief component of commercial digitoxin. It is decom- posed by water, ether, and carbon disulphide. The aqueous solution froths on shaking, and is precipitated by tannin. It gives a reducing sugar when boiled with water or alcohol. Sulphuric acid containing ferric chlo- ride produces a violet color. When dissolved in acetic acid, ferric chloride added, and then treated with sul- phuric acid containing ferric chloride, the acid becomes indigo-blue, and the zone of contact violet. The color reactions given with sulphuric acid are usually only characteristic when the substances are pure and alone. Thus if resorcinol is present at the same time as narcein, and had not been entirely removed by ether, a crimson color woidd appear; or if a trace of tannin were present with hydrastin, narcotin, or narcein, a green color would be obtained. The reaction with resorcinol and sulphuric acid is very characteristic for narceia. Add sufficient ammonia water to render the acid solu- tion distinctly alkaline, and note the appearances. A green color indicates apomorphin. If the acid solution was red, due to the presence of sanguinarin, the red color 36 THE QUALITATIVE ANALYSIS OF will disappear on the addition of ammonia. If a red color appears on the addition of ammonia, physostigmin is indicated. The following substances will cause a fluorescence: Manaca, sumbul, hydrangea, hydrastin, gelsemium, and pichi, which gives a blue fluorescence with ammonia. Now shake out three times with P.E. Wash the combined solvents with water, filter into a beaker, and evaporate over the steam-bath, using fan. The following substances will be removed: * Acoin base trace Aconitin trace i82°-i86°, slow heating Alypin Aniline Atropin trace ii2°-ii3° Benzoylecgonin 90° when hyd., 195° anhyd. Betaeucain base Brucin trace 178° Capsicin Chelerythrin Cocain 98° Conhydrin ii8°-i2i° Coniin Emetin trace Gelsemium bases, small amount Gujasanol base Holocain base trace Hydrastinin ii6°-ii7° Lupanin Lycoctonin * The italics are used to call attention to the commoner substances. MEDICINAL PREPARATIONS 37 Methylconiin Nicotin Novocain base 5i°-6o° Peronin base, somewhat Physostigmin trace Quinin traces i7i°-i72° anhyd. Quinolin Rubijervin trace Sanguinarin trace Spartein trace Stovain base Strychnm, partly 26$°-26if Tropacocain 49° Trimethylamin Veratrin trace Yohimbin trace Pyramidon io6°-io7° Pimento bases Sarracenia purpurea base Taraxacum base Note the appearance of the residue after the solvent is evaporated. Liquid: Nicotin, spartein, coniin, beta-eucain, guja- sanol, physostigmin. Quinolin, alypin oUy. Coca alkaloids give an oily residue if in small amounts, but if in quantity the cocain crystallizes in the mass. Amorphous: Antipyrine, brucin, sanguinarin, yo- himbin. * The italics are used to call attention to the commoner substances. 38 THE QUALITATIVE ANALYSIS OF Hard, colorless, resinous mass: Quinin. Odor: Tobacco-like, nicotin. A portion diluted with a little H2O: Mousy odor, coniin. Guaiacol-like, Gujasanol. Pungent, pyramidon odor: Spartein. Test for alkaloid: Dissolve the residue in P.E., remove five drops, place on watch-glass, and evaporate. Dis- solve in one to two drops N/i H2SO4, and add Mayer's reagent. A precipitate indicates an alkaloid. Note the color of this precipitate. If the solution in H2SO4 is red, and a red precipitate is obtained, sanguinarin is indicated. Physiological test: Evaporate ten drops P.E. solution on a watch-glass, concentrating as much as possible in the centre of the glass. If aconitin is suspected, per- form the test very carefully. Remove a bit on the end of a glass rod and apply it to the end of tongue, rubbing it with the rod. Tingling after one to five minutes indi- cates aconitin. Bitter indicates strychnin and quinin. Numbness at once, or after a few minutes, indicates cocain, heta-eucain, tropacocain, acoin, gujasanol, holo- cain, novocain, stovain. Anesthesia is not always obtained with such small quantities, and if no tingling is experi- enced, indicating aconitin, remove a larger quantity on the end of the finger and rub it thoroughly over the end of the tongue. If no sensation of numbness becomes apparent after five minutes it is doubtful if any of the anesthetics are present. If the residue was oily, evap- orate ten drops P.E. solution, and treat with five to ten drops H2O. Physostigmin will dissolve quite readily. Apply a few drops of this solution to the eye of spme MEDICINAL PREPARATIONS 39 animal having a normally large pupil, and note whether there is any contraction indicating physostigmin. Evaporate five drops of P.E. solution in a porcelain dish and treat residue with two drops H2SO4 containing K2Cr207. Purple color indicates strychnin, yohimbin, gelsemium bases. If coniin is present, an odor of butyric acid will be noted. The change of color in the case of strychnin is purple to cherry-red, gradually fading. Yohimbin gives a purple, but no change like strychnin. Evaporate five drops of P.E. soliition in a porcelain dish, and treat residue with five drops concentrated HNO3. Red color indicates brucin, acoin. Purple-red to dirty yeUow indicates gelsemium bases. Orange color indicates sanguinarin. Yellow soon turning orange, physostigmin. Now evaporate over the steam-bath (if any antipyrine is present the mixture will become deep purple on heat- ing with HNO3), and after the acid is entirely dissi- pated, as determined by the odor, cool the dish and add five to ten drops "alcoholic potassa, noting carefully the odor, and, at the same time, the color produced. An agreeable odor of ethyl benzoate indicates cocain, acon- itin, tropacocain, stovain. The odor should always be compared with that given by a known residue until the operator is familiar with it. In the case of stovain, the odor of isonitrile is also present. A purple color indi- cates antipyrine, strychnin, yohimbin, atropin. A red color indicates holocain. If no odor develops in the cold, warm slightly over the steam-bath. Acoin also gives an agreeable odor, but not that of ethyl benzoate. Alypin gives a disagree- able odor. 40 THE QUALITATIVE ANALYSIS OF Evaporate five drops in a porcelain dish and add two drops formaldehyde-sulphuric acid. A crimson color gradually becoming purple indicates peronin. Repeat, using Froehde's solution, and the following color-reactions wiU be obtained in the presence of peronin: Blue, deep violet, soon fading to dirty brown, then green, and finally slate color. There are a number of alkaloids which appear in small amounts in this fraction, while the greater por- tion will be extraicted subsequently by ether and CHCI3, and confirmatory tests wiU give better results when performed on these fractions. This appHes to atropin, aconitin, brucin, emetin, holocain, physos- tigmin, quinin, sanguinarin, spartein, strychnin, and yohimbin. If the residue consists of crystals apparently pure, determine the melting-point. In order to purify a residue, dissolve in dilute HCl and precipitate with iodine in KI. Filter and wash with I solution. Dissolve the precipitate in H2SO3, pour into separator, add NH4OH in excess, and shake out with P.E., wash, filter solvent into beaker and evaporate, which will give a residue of pure alkaloid. Perform several microchemical tests with the residue. Most of the alkaloids give, with certain reagents, precipi- tates having characteristic forms. This test is most valuable for confirming the identity of an individual. A check should be carried out at the same time with a known sample, until the analyst is f amihar with the reac- tions. The preliminary tests with the color-producing reagents will indicate the alkaloid to be tested for. Cocain gives very characteristic precipitates with gold MEDICINAL PREPARATIONS 41 chlorid, PdCl2, KMn04, picric acid; and the other anes- thetics give characteristic tests. Coniin and nicotin are volatile, and may be separated from the others of this group by boiling in a current of steam. The distillate shoxild be cooled and then shaken out with P.E., and the solvent filtered and evaporated. A portion of this residue on treatment with AgNOs solution will act as follows: Free coniin gives a brown precipitate of AgaO, which afterward becomes black. Nicotin gives a white precipitate, turning dark on exposure to light. A solution of the residue or of a neutralized acid solu- tion of the residue with HgCU, gives a white amorphous precipitate with coniin, and a crystalline precipitate with nicotin, both readily soluble in HCl or acetic acid. Nicotin and strychnin are the only alkaloids giving crystalline precipitates with HgGl2. Sl;jychnin is nearly insoluble in acetic acid. Of course if the residue had been obtained by distillation no strychnin would be present. A solution of the residue in dilute HCl treated with PtCli solution gives a crystalline precipitate with nicotin. Coniin does not give a precipitate unless very concentrated. The PtCU compoimd of nicotin melts at about 275°, darkening at 250°. This should be con- firmed with a sample of a known product. A solution of the residue in dilute HCl treated with picric acid solution gives a precipitate with nicotin, but not with coniin, except in very concentrated solu- tion. Nicotin picrate forms prisms melting at 2 18°. Now shake out three times with ether; if ether solu- tion is green, it indicates apomorphine. Wash the com- 42 THE QUALITATIVE ANALYSIS OF bined solvents with water, filter into a beaker, and evap- orate over a steam-bath, using a fan. The following substances will be removed : * Acoin base Aconitin Adrenalin, slightly Anesthesin 89°-9i° Antipyrine ii2°-ii3° Apomorphin, partly Apocodein Atisin from Aconitum heterophyUum Aspidospermin Atropin ii2°-ii3° Bebeerin Boldin Brucin 178° Cannabin Carpain Cephaelin 130° Cevadin Chehdonin, slightly Cinchonamin Cinchonidin trace 200-207° Cinchonin trace 240-250° Coca bases not readily sol. in P.E. Codein iS4°-iS5° Conessin (Wrightin) Corydalin Cuprein 198° * The italics are used to call attention to the commoner substances. MEDICINAL PREPARATIONS 43 Cytisin 152° Delphinin 119° Dionin base Emetin Ephedrin Ergotinin Euquinin Geissospermin 160° Gelsemin 178° Gelseminin Harmalin Heroin trace 171"^ Holocain 121° Homatropin 98°-99° Homoarecolin Hydrastin 132° Hydrocotarnin Hydroquebrachin Hyoscyamin io6°-io8° Jaborin Jervin trace Laudanin, slightly Laudanosin LobeKn Methylene Blue Novocain 5i°-6o° Nupharin Orthoform I4i°-i43° Oxyacanthin 210° Oxyspartein 84° * The italics are used to call attention to the commoner substances. 44 THE QUALITATIVE ANALYSIS OF Papaverin 147° Pereirin Pelletierin Peronin base Physostigmin Pilocarpin Pseudaconitin from Aconitum ferox Pseudopelletierin Quebrachamin 142° Quebrachin 2i4°-2i6° Quiiudin, sparingly i68°-i70° Quinin i'ji°-i'j2° anhyd. Quinolin Rubijervin trace Sabadin Sabadinin trace Scopolamin 59° Sanguinarin Spartein Strychnin 26^°-26