The chemistry of synthetic drugs / by Percy May.

  • May, Percy, 1886-
Date:
1911
Catalogue details

Licence: In copyright

Credit: The chemistry of synthetic drugs / by Percy May. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    Lut on further ascending the series, the action diminishes owing to their diminished volatility and solubility, so that the higher members are quite inert. The members of the ethylene series have a similar narcotic action; amylene, C0Hi0, resembles chloroform in its narcotic properties. The benzene hydrocarbons have a paralyzing action on the motor nerves, and a more noteworthy action on the brain and cord, causing lethargy and somnolence. Bromobenzene and chlorobenzene act in the same way as benzene itself. Naphtha- lene, CioH8, is less toxic than benzene, but slows the respiration and, in fever, lowers the temperature. It also has the property of decreasing nitrogen metabolism. Diphenyl is physiologically inert, while thiophene, furfurane and pyrrol resemble benzene to a certain extent. Effect of Alkyl Groups.—Some of the effects of intro- ducing alkyl groups into a compound have already been mentioned in connection with Schmiedeberg's rules, but there are many different effects to which attention may be given. The convulsive properties of ammonia are diminished by the entrance of methyl groups, trimethylamine being free from these effects. In aniline, replacement of the hydrogen of the amino group causes diminution of the convulsive properties as with ammonia, but replacement of the hydrogen of the nucleus by methyl groups causes an increase in these effects. The, marked influence of the entrance of methyl groups into the xanthine molecule has already been pointed out. The foregoing- examples show that the addition of a methyl group to a nitrogen atom can produce very diverse effects, and a similar variety can be found in the effect of the methylation of an hydroxyl group. The alkyl ethers of the type E. 0 . E, where E represents an aliphatic hydrocarbon radicle, are distinguished by their resistance towards oxidation, and physiologically they show a marked hypnotic action, as in the case of ordinary ethyl ether, C2H5—0—C2H5. This hypnotic action is also shown by many other compounds containing an ethoxy group, — 0—C2H5, such as ethoxy-caffeine. In many cases, replacement of the hydrogen of an hydroxyl group by a methyl group diminishes the physiological activity. oil For instance, more poisonous than