The constituents of chaulmoogra seeds / by Frederick B. Power and Frank H. Gornall.

  • Power, Frederick B. (Frederick Belding), 1853-1927.
Date:
[1904]
Catalogue details

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: The constituents of chaulmoogra seeds / by Frederick B. Power and Frank H. Gornall. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    sufficient water to precipitate the whole of the acids remaining in solu- tion, which separated as a somewhat oily cake ; the latter was then subjected to pressure, and was thus separated into 1500 grams of solid acids, which, after purification, melted at 36—38°, and 950 grams of a light brown oil. Identification of Palmitic Acid. The 950 grams of oil obtained by expression, as stated above, were fractionally distilled, when practically the whole passed over between 210° and 235°/10 mm. A fraction which distilled between 210° and 220°/10 mm. was separated; it passed over as a slightly yellow oil, which, however, solidified on cooling. In order to remove some adher ing oil, it was drained at the pump and finally on porous earthenware. The dry acid was then crystallised, first from methyl alcohol, then from acetone, when it melted at 62—63°, and finally from ethyl acetate, when its melting point remained unchanged. It was definitely shown to be palmitic acid by analysis and titration, by the estimation of silver in its silver salt, as also by the fact that it was optically inactive and behaved as a saturated compound towards bromine and permanganate. Isolation of a New Unsaturated Acid, Chaulmoogric Acid, CjgHggOg. In the course of the fractional crystallisation of the fatty acids (p. 845), the isolation of a large quantity of an individual substance, melting at 68°, was noted. 0-1416 gave 0-3976 COg and 0T460 H2O. C = 76-6; H=11'5. 0-1432 „ 0-4046 002 »» 0-1500 H2O. 0 = 77-0; H = 11-6. 0-1344 „ 0-3783 002 „ 0-1388 H2O. 0 = 76-8 ; H = 11-4. 0jgH3202 requires 0 = 77-1; H = ll-4 per cent. The silver salt was prepared from an alcoholic solution of the ammonium salt, and formed a white, amorphous precipitate, which was washed successively with water, alcohol, and ether. 0-1280 gave 0-0356 Ag. Ag = 27-8. 0-0884 „ 0-1804 OOg, 0-0666 H2O, and 0-0246 Ag. 0 = 55-7; H = 8-4; Ag = 27-8. OjgH^OjAg requires 0 = 55-8 ; H = 8-0 ; Ag = 27'9 per cent. 0-6914, in alcohol, required NaOH equivalent to 24-6 c.c. of a decinormal solution, and 0-8022 required 28-6 c.c., which are the calcu- lated amounts for OjgHjgOg. It is thus quite evident that the acid melting at 68° has the formula 0jgH3202, and is isomeric with linolic acid, v/hich belongs to the series CnH.2n-fil2- known acids of this series are