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AN INTRODUCTION

TO

CHEMICAL PHARMACOLOGY



McGUIGAN



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AN INTRODUCTION

TO

Chemical Pharmacology



Pharmacodynamics in Relation j >
to Chemistry . ., ^



BY

HUGH McGUIGAN, Ph.D., M.D.

PROFESSOR OF PHARMACOLOGY, UNIVERSITY OF ILLINOIS,
9OLLBGB OF MEDICINE



PHILADELPHIA
BLAKISTON'S SON & CO.

1012 WALNUT STREET



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aiOLOGY
UBAARV



Copyright, 1921, by P. Blakiston's Son & Co.



TSa MAPI.a PXKSS TOKK PA



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: f



PREFACE

Before the foundation of a science is definitely laid, many facts
must be established, analyzed and correlated. In obtaining
these facts many methods may be used and many fields studied.
This is especially true of the science of pharmacology, the founda-
tion of which rests on anatomy, physiology, chemistry and
physics. It is natural therefore, in the development of pharma-
cology, that research should have proceeded in waves, during
which anatomy, physiology, physics or chemistry, played the
predominant r61e. The sequence of such waves may be due to
the investigator following the line of least resistance or to the
influence of a dominant character in the science. Finally how-
ever, such waves are spent, and new methods of attacl^ are
developed, often in a new field.

The period of pure physiological methods in which changes in
blood pressure, respiration or heart rate have been recorded, f 9r
the present seems spent, and many are convinced that chemistry
now offers the most hopeful method for the solution of many
problems of pharmacology.

The changes in blood pressure, respiration, secretion or meta-
bolism, after the administration of drugs are fundamentally due
to a chemical reaction between the drug and the tissue. Physi-
cal changes also result, and it is often difficult to separate the
purely physical from the purely chemical. The fact that we
know little of the chemistry involved in many cases where the
dynamic reaction is most pronoimced cannot be used as an argu-
ment against the importance of a study of the Chemical Pharma-
cology. Rather our ignorance of such a reaction should stimulate
chemical investigation concerning many life processes. The
dictum of the great physiologist who said "Ignoramus, Ignora-
bimus," must apparently remain true, until chemical investiga-
tion gives the explanation.

The field of Chemical Pharmacology is so immense that it is
possible to present only a small part of it within acceptable



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VI PREFACE .

limits. However, much of it is co-extensive with Biological
Chemistry and the aim of this work is to select for emphasis
those chemical reactions, which, in the various branches, have
an especial relation to pharmacology.

The following facts, therefore, have been collected and are
presented from the point of view of pharmacology, in the beUef
that students of chemistry, pharmacy, biology, and medicine
should become more famiUar with this branch of the subject.
The writer is also of the opinion that in the teaching of pharma-
cology, the chemical side should receive much more attention
than it does at present. In this way the student will have an
opportunity to review and add to his previous work in chemistry,
and enter the cUnical years better equipped and with a fuller
appreciation of the most promising avenue of advance.

In the preparation of this work many sources of information
have been used. Original papers are not' quoted because in an
elementary work the student wishes a general survey of the field
and when he attains the stage in which he is able to digest litera-
ture the sources are readily found. The following works among
others have been freely used and contain the original references:
FrankePs Arzneimittel Synthese; The Chemical Basis of Pharma-
cology — Francis and Fortescue — Brickdale; Cushny, Text-book
of Pharmacology ;Sollmann, Manual of Pharmacology; Richter's
Organic Chemistry; Mathews, Physiological Chemistry; Henry's
Plant Alkaloids; Barger, Simpler Natural Bases; Kobert's
Lehrbuch der Intoxikationen; Armstrong, Carbohydrates and
Glucosides; Haas and Hill, Chemistry of Plant Products. I
am especially indebted to my colleague in the department,
Harry Victor Atkinson, for help in proof, reading and for many
suggestions.



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TABLE OF CONTENTS

Page

I. Intkoduction 1

Definitions, 1 — Classifications, 1 — Organic . drugs, 3 — Composi-
tion of drugs, 4 — Carbon, 4 — Test for hydrogen, 7— Nitrogen, 7 —
Test for nitrogen, 8 — Nessler's test, 8 — Kjeldahrs test for nitro-
gen, 9 — Oxygen, 10 — Ash, 10. *

II. Parapfins 12

Properties of the hydrocarbons of the paraffin series, 12 — Crude
petroleum, 13 — ^Liquid petrolatum, 14 — Occurrence in nature, 15
— Synthesis of methane, 16 — Ethane, 16.

III. Important Drugs OF THE Methane Series 17

Tests for methyl alcohol, 18 — Ethyl alcohol, 19 — Alcohol impor-
tance of, 20 — The destructive action on the tissues, 21 — Alcohol

as a food, 21 — The fate of alcohol in the body, 22 — Chemical tests
for ethyl alcohol, 23 — ^Lieben's iodoform test, 23 — Ethyl acetate
test, 23 — To determine the amount of ethyl alcohol in Hquors, 24 —
Propyl and butyl alcohols, 24 — Amyl alcohol or pentyl alcohol,
26— Dihydric alcohols, 28— Glycol, 29— Trihydric alcohols, 29—
Chemical test, 29 — Higher alcohols, 30 — Sulphur alcohols or mer-
captans, 30 — Pharmacology of the alcohols in relation to their
chemistry, 31.

IV. Anesthetics, Narcotics, Soporifics, Hypnotics 32

Anesthesia, 33 — ^Anesthetics, 35 — Theories regarding the causa-
tion of anesthesia, 36 — The Meyer-Overt on theory, 36 — The
theory of Moore and Roaf, 37 — Verworn's theory, 37 — The Hy-
derabad Commission— 1889 and 1890, 37 — Ether anesthesia, 39 —
Ether or ethyl oxide, 39 — Chemical tests, 39 — ^Ethyl chloride, 41 —
Hypnotics and analgesics of the methane series, 41 — The chloro-
form group, 41 — Chemical tests, 42 — ^Phenyl isocyanide test, 43 —
The urethane group of hypnotics, 43 — Veronal, 44 — Chemical
tests, 45 — The sulphone group of hypnotics, 45 — Sulphonal, 46 —
Trional, 46 — Tetranol, 47 — Chemical tests, 47.

V. Aldehydes. . 48

General properties of aldehydes. Reactions, 48— Tests for for-
maldehyde, 52 — ^Lieberman's test, 52 — Rimini's method, 52 —
< Phloroglucinol test (Jorissen), 53 — Phenylhydrazin — HCl method,
53 — Phenylhydrazine hydrochloride and ferrocyanic method, 53 —
Hexamethylenamine, 54 — Acetaldehyde, aldehyde or ethanal, 55 —



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Paos
Paraldehyde, 57 — Chloral and chloraldehyde, 57 — Chloral and
chloral hydrate, 58 — The fate of chloral in the body, 59 — To test
urine directly for chloral, 61 — Nessler's solution test, 61 — Chlora-
lose, 61 — Chemical tests, 61.

VI. Ketones 62

Acetone, 62 — Chemical tests, 63 — ^Legal's test, 63 — Penzoldt's test,
^—Reynold's test, 63— Chloretone, 63.

VII. Organic Acids ^ 64

Organic acids of methane series, 65 — Acetic acid, 66 — Carbonic
acids, 67 — Urea, 68 — Oxalic aicid, 69 — Malonic acid, 70 — Succinic
acid, 71 — Tartaric acid, 71 — Citric acid, 73 — ^Lactic acid, 74 —
Hydrocyanic acid, 75 — Prussian blue test, 77 — Vortmann's nitro-
prusside test, 77 — Picric acid test, 77 — General pharmacology of
the acids, 78.

VIII. lODOPORM AND PHYSIOLOGICAL SUBSTITUTES 79

Lustgarten's test, 80 — Phenylisocyanide test, 80 — Iodoform sub-
stitutes, 81 — The fate of iodoform in the body, 84 — Bromine com-
pounds, 85.

IX. Benzene or Benzol 86

X. Phenols 89

Properties of phenols, 90 — Quinol or hydroquinone or para dihy-
droxy benzene, 92 — Dihydroxy phenols or dihydroxy benzenes, 92
— Pyrocatechol, 93 — Trihydroxy benzenes or trihydric phenols,
94 — Phloroglucinol, 94 — PyrogaUol or pyrogallic acid, 94 — Cresols,
95 — Creosote, 97 — Picric acid, 97 — Tests for picric acid, 97— Re-
actions of the phenols, 98 — The salol principle, 100 — Friedel and
Craft's Reaction for Toluene Synthesis, 101.

XI. Aromatic Alcohols, and Phenol Alcohols 101

Saligenin, 102 — Aldehydes of the aromatic series, 103 — Benzalde-
hyde, 103 — Ketones of the aromatic series, 104.

XII. Acids and Related Compounds 104

Benzoic acid, 104 — Mesotan, 107.

XIII. Aniline and Toluene Derivatives 109

Tests for aniline, 112 — Acetanilide, 112 — Antipyrine or phenyl
dimethylpyrazolon, 113 — Pyrazolon, 114 — Antipyrine, 116 —
Pyramidon, 117 — AcetaniUde tests, 119 — Tests for antipyrine,
119 — Salicylic acid tests, 120 — Phenacetin, Acetphenetidine, 120 —
Saccharin, 121— Thymol iodide, 122— Phenolphthalein, 123— De-
termination of kidney function, 126.

XIV. Naphthalenes (tar camphor) 127

Anthracenes, 128 — Quinones, 130.



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XV. Hetero Cyclic Compounds 133

XVI. Carbohydrates 134

Mono8acch£U*ides, 134 — DisaccharideS) 134 — Polysaccharides, 134
^Difference between starches, gums, celluloses and sugars, 135 —
General tests, 135 — Molisch's reaction, 136 — Starches, 137 —
Tests for starch, 137 — Sugars, 138 — Fermentation, 138 — The uses

of sugars, 138 — Cellulose, 139— rTests for cellulose, 140 — Crude
fiber, 139— Hemicellulose, 140— Agar, 140— Gums, 141— Tests
for gums, 141 — Pectins, 142 — Method of preparing pectin, 143.

XVII. Fats and Fixed Oils 144

Classification of oils, 144 — General properties of fats, 148 — ^Ex-
planation of the cleansing action of soap, 149 — The characteriza-
tion of fats, 151 — ^Fat constants, 152 — The hydrogen number and
hydrogenated fats, 154 — The Reichert Meissel numbers, 155 —
The acetyl number, 155— The Elaldin test for fats, 156— The bro-
mine test, 157 — Maumen^ or sulphuric acid test, 157 — ^Rancidity of
fats, 158— The significance, uses imd fate of fats, 158 — Origin of

fat in the animal, 160 — ^Fats from proteins, 162 — The need of
fats in growth, 163— The fate of fats in the body, 163.

XVIII. Waxes 164

Sterols, 166— Cholesterol, 165— Tests for Cholesterol, 167— Schiff 's
reaction, 168.

XIX. Volatile, Ethereal or Essential Oils 168

Chemical classification, 169 — Aliphatic hydrocarbons in volatile
oils, 169 — Terpenes, 169 — Aromatic terpenes, 171 — Aliphatic

. alcohols in volatile oils, 173 — Aromatic alcohols in volatile oils,
173-7Diflferences between fixed and volatile oils, 173 — The general
action of the volatile oils, 174 — Action on the alimentary tract,
174 — Substances excreted combined with glycuronic acid, 175 —
The significance of glycuronic acid in the urine, 175 — Saponifica-
tion, 176 — Stearoptenes, 177 — Thymolis iodidum, 179.

XX. Resins, Oleoresins, Gxtm Resins, and Balsams 180

Oleoresins, 181 — Gum resins, 182 — Balsams, 182.

XXI. Glucosides or Compound Sugars . 183

Pentosides, Gralactosides, etc., 183 — Constitution of the glucosides,
183 — Glucosides, 185 — Composition of natural glucosides, 188 —
Ethylene derivatives, 191 — Benzene derivatives, 192 — Phloridzin,
193 — Styrolene derivatives, 194 — ^Anthracene or anthraquinone de-
rivatives, 195 — Saponin or saponins, 196 — The digitalis glucosides,
196— Digitalin, 197— Digitonin, 197— Convallamarm, 197— Digi-
talein, 197— Glycyrrhizin, 197— Scillin, 197— Helleborin, 197—
Cyanogenetic glucosides, 198 — Solanin, 198 — Coniferin, 199 —



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Indican, 199 — Indoxyl, 200 — ^Animal glucosides, 201 — The func-
tions, action, and fate of glucosides, 202 — Tests for glucosides, 203.

XXII. Bitter Principles 204

Tests to distinguish bitters from other bodies, 204 — Pharmacologic
classification, 204.

XXIII. Pharmacology op the Taste and Smell 205

Chemistry and physics of odors, 207 — Taste, 208 — Glucophore,
212.

XXIV. Tannic, DiGALLic Acid OR Gallotanic Acid 214

Fate in the body, 216 — Determination, 218.

XXV. Neutral Principles 218

Santonin, 219— Tests, 220— Picrotoxin, 220— Tests, 220— H.
Meltzer's test, 220— Langley's test, 221 —Physiologic test, 221—
Elaterin, 221— Chrysorobin, 221.

XXVI. Alkaloids 222

Nitrogen bases; plant bases or alkaloids, 222 — General characteris-
tics of alkaloids, 224 — Chemistry of alkaloids, 225.

XXVII. Amines or Substituted Ammonias 225

Tests for amines, 226 — Quaternary ammonium bases, 228 — Sources

of amines, 229 — The physiological action of the amines, 230 —
Amines with two hydroxyl compounds, 232 — Alkaloids derived
from aliphatic amines, 234 — Epinephrine test, 237 — Arginine, 238
— The fate of arginine in the body, 238 — Ptomaines or putrefactive
alkaloids, 239 — Choline, 242 — Ergot alkaloids, 244 — Ergot amines,
245 — Pyridine alkaloids, 247 — Natural methylated compounds in
the body, 249 — The fate of creatine and creatinine in the body, 249
— Tests, 252 — Nicotinic acid, 255— Tests for nicotine, 255 — Rous-
sin's test, 255 — Schindelmeiser's test, 256 — Physiological tests,
256— Strychnine, 256— The fate of strychnine, 256— Tests for
strychnine and brucine, 257 — Bichromate, test, 257 — ^Physiologic
test, 257 — Brucine, 257 — Arecoline, 257 — Quinoline, 258— Quino-
line alkaloids, 259 — Action, 259 — The fate of quinine in the body,
259 — Assay of the alkaloids in cinchona bark, 260 — Tests for
quinine, 261 — Thalleioquine test, Isoquinoline alkaloids, 261 — ■
Hydrastine and hydrastinine, 262 — Hydrastinine, 263 — Hydras-
tine tests, 263 — Hydrastinine, 264 — Narcotine, 264 — Tests for
narcotine, 265 — Action of cocaine, 266 — The fate of cocaine in the
body, 266 — ^Artificial cocaines, 267 — Tests for cocaine, 267 — The
pyrrol or pyrrolidine group of alkaloids, 267 — The fate of atropine
in the "body, 271— Tests for atropine, 272— Vitali's test, 272—
Scopolamine or Hyoscine, 272 — The glyoxaline group of alkaloids,
273 — Action of pilocarpine, 274 — Fate in the body, 275 — ^Tests for
pilocarpine, 275 — Phenanthrene alkaloids, 275 — Phenanthrene



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CONTENTS XI

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group, 275 — Apomorphine, 279 — Apocodeine, 279 — The fate of
these alkaloids in the body, 280 — Tests for apomorphine, 280 —
Tests for codeine, 281 — Tests for morphine, 281 — Tests for the-
baine, 282— Papaverine, 282— Tests, 283— The caffeine group, 283
— Guanine, 287 — ^Adenine, 287 — Murexide test, 288 — Action of
caffeine compounds, 288 — The diuretic action of caffeine, 289 —
Fate of caffeine in the body. Economic use of caffeine, 291 — Isola-
tion of alkaloids, 292 — Power and Chestnut's method of assaying
caffeine in vegetable material, 292— Isolation of caffeine, 293 —
Keller's method, 293— Unclassified alkaloids, 294— Veratrine, 294
— Physostigmine or eserine, 294 — Tests, 295 — Colchicine, 295 —
Tests, 295 — Unclassified or alkaloids of unknown composition,
296 — The physiological significance of nitrogen bases, 297.

XXVII. Proteins 298

Classification of proteins, 299'^-The simple proteins, 299 — Conju-
gated proteins, 300 — Derived proteins, 301 — A. Primary products,
301 — B. Secondary or intermediate protein derivatives, 301 —
Comparison of animal and vegetable proteins, 302 — ^Amino acids
found in plants, 302 — General properties of proteins, 303 — Color
reactions, 303 — Precipitation reactions, 304 — Hydrolytic products,
304 — General characters of amino acids, 308 — Condensation prod-
ucts, 309 — Condensation with formaldehyde, 311 — The deamini-
zation of amino acids, 312— Ure thane formation or the carbo-amino
reaction of amino acids, 313 — The taste of amino acids, 314 —
Optical properties of amino acids, 314 — The action of amino acids

in the body, 315 — The fate of amino acids in the body, 316 — The
fate of alpha amino acids in abnormal conditions, 319 — Trypto-
phane, 321 — Poisonous proteins, 322.

XXVIII. Enzymes or Organic Ferments 323

Enzymes used as medicines, 324 — Pancreatic ferments, 324 — The
fate of enzymes in the body, 325.

XXIX. Chlorophyll . 328

Relationship of chlorophylls and hemoglobins, 329— The fate of
chlorophyll in the body, 333 — Other plant colors, 333.

XXX. COLLOIDB 335

Character, or nature, of colloids, 336 — Classification, 338 — ^Dif-
ferences between the suspensoid and emulsoid colloids, 338 — ^Gel
formation, 339 — Lyotrope series, 340 — Electric conditions of col-
loids, 341 — Protective power of colloids, 342 — Change in colloids

in gel formation and precipitation, 342 — Surface tension, 343 —
Viscosity and surface tension, 345 — Superficial viscosity, 347 —
Relation of composition to surface tension, 347 — Relation of com-
. petition to viscosity, 348 — ^Adsorption, 349 — Selective adsorption,
349 — Influence of salts on absorption, 349.



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XU CONTENTS

Faoe

XXXI. The Reaction of Livino Matter 350

The colorimetric method, 351 — Electro- potential method or gas
chain method, 351 — Method of expressing hydrogen ion concentra-
tion, 352 — Regulating mechanism, 354 — Actual and potential al-
kalinity and buffer value, 355 — Potential alkalinity of blood, 356

— Acidosis, 357 — The determination of the existence of acidosis,
359 — ^Tolerance to carbonate, 359 — ^Urinary changes, 360 —
Lowered tension of carbon dioxide in the respired air, 360.

XXXII. Phosphorus .361

The fate of phosphorus in the body, 364 — Arsenic compounds,
364 — Fate of arsenic in the body, 367.

XXXIII. Heavy Metals. . 368

Explanation of precipitation, 369 — Colloidal metals, 372.

XXXIV. Inorganic Acids 373

XXXV. Salt Action 374

Diffusion, 375 — Osmosis, 375 — Gas pressure in relation to osmotic
pressure, 375 — DiflBculties in determining osmotic pressure, 376 —
Relation of osmotic pressure to the boiling point and freezing point

of solutions, 377 — Freezing point method, 377 — To calculate the
osmotic pressure from the freezing point, 377 — Salts in the body,
378 — Salt action in pharmacology, 379.

XXXVI. Toxicology 379

The isolation of poisons, 379 — Apomorphine, 381 — Methods of
isolating poisons, 382 — The isolation of volatile poisons, 382 —
Preliminary test for phosphorus, 382 — Discussion of results, 382 — .
Mitscherlich's test, 383 — Ammonium-molybdate test, 385 —
Ammonium magnesium phosphate test, 385 — The Mitscherlich-
Scherer method for the qualitative and quantitative estimation of
phosphorus, 386 — Tests for detection of phosphorus in oils, 387 —
Acetone, 387 — Aniline, 387 — Oil of bitter almonds or benzalde-
hyde, 387 - Test for KCN, 387— Carbon bisulphide, 388— Chloral
hydrate, 389— Ethyl alcohol, 389— Methyl alcohol, 390— Iodo-
form, 390 — Nitrobenzene, 390— Phenol, 390 — Quantitative esti-
mation of phenol, 390 — Creosote (Creosols), 390 — Non-volatile
organic poisons, 391 — ^Acid extraction Stas-Otto method, 392 —
Metallic poisons, 394-^Arsenic test, 396 — Detection of antimony,
397 — Differences between arsenic and antimony, 398 — Test for
mercury, 398 — ^Examination of the nitric acid solution, 399 —
Copper and bismuth tests, 399 — Chromium and zinc, 399 — Synop-
sis of metallic poisons, 400 — Sulphuric acid, 401 — Nitric acid
tests, 401 — Oxalates and oxalic acid, 402 — ^Alkalies, 403 — Fixed al-
kalies, 403 — Potassium chlorate, 403 — ^Active substances which find

no place in the Stas-Otto method, 403 — Santonin, sulphonal; trionul,
404 — Digitalis, 405 — Ergot, 405 — Reagents and solutions, 406.



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CHEMICAL PHARM:^COtO&Y'

I. INTRODUCTION

Pharmacology is the science which deals with drugs and the
reactions of living matter brought about by drugs. The term,
"drug" is derived from the Dutch or Anglo-Saxon word, "drugan,"
meaning to dry, and was formerly applied to dried medicinal
plants. At that time materia medica was entirely of plant origin,
at present the term includes all substances used as remedial
agents.

It is often desirable to define foods, drugs, and poisons; but
the distinctions at best are unsatisfactory and arbitrary. Foods
are substances, which, when taken into the alimentary tract are
digested, build up tissue, supply energy, repair waste, and do not
injure health. A poison is anything that, in amounts of fifty
grams or less, injures or destroys life, when taken by mouth.
There is, however, no satisfactory definition of a poison, and
fifty grams is an arbitrary amount; some set the limit at one
gram. Drugs and poisons are relatively little acted on by the
body, are but little digested or hydrolyzed, and as a rule do not
supply energy, and do not repair waste. Some substances, may
be remedies, foods, or poisons, according to the method of adminis-
tration; e.g. egg albumen and peptone, are foods when taken
by mouth, but they are violent poisons if given intravenously.
Iron salts too,, when taken by mouth are valuable remedies in
some cases of chlorosis, but they also may exert a toxic action if
given by vein. Some foods such as milk, fish and strawberries



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