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

  • Frederick Belding Power
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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    unsaturated to the extent of two ethylenic linkings, or, in other words, combine directly with four atomic proportions of bromine or iodine. They are, therefore, all open chain, unsaturated acids. The acid melt- ing at 68°, however, combines directly with only two atomic propor- tions of bromine or iodine. 0’7428 absorbed 0’6697 iodine. I = 90’l. CigHjgOj, with one ethylenic linking, requires 1 = 90*6. CigHggOg, with two ethylenic linkings, requires 1 = 181*2 per cent. This fact, together with some results recorded in the following paper, shows that this acid, although having the general formula GnH^2n-i02f contains only one ethylenic linking j it, therefore, must necessarily contain a closed carbon ring. In view of this conclusion, it became clear that it represents a new substance, since no acid of an alicyclic nature has hitherto been isolated from the fats or oils. On account of the vernacular name of the oil from which it has been isolated, it has been decided to designate this new acid as chaulmoogric acid. Another interesting character of the acid, which again differentiates it from any of the known acids of the same formula, is its optical activity. A solution containing 3*892 grams in 100 c.c. of chloroform gave ai)-t-2°ll' in a 1 dcm. tube, whence [a]o-l-56°. Chaulmoogric acid, as compared with its known isomerides, is a very stable substance ; it can be distilled without the slightest decomposi- tion, and passes over at 247—248° (corr.)/20 mm. as a colourless oil, which soon solidifies to a solid, crystalline mass. The distilled acid was analysed. 0*1258 gave 0*3545 COg and 0*1316 HgO. 0 = 76*9; H = ll*6. CigHgjOg requires 0 = 77*1 ; H = 11*4 per cent. Chaulmoogric acid is readily oxidised by cold potassium perman- ganate or nitric acid. It is also readily attacked by concentrated sulphuric acid, with much decomposition and the evolution of sulphur dioxide. It is sparingly soluble in, and can readily be crystallised from, the usual organic solvents, with the exception of chloroform and ether, in which it is easily soluble even in the cold. It is also soluble in aqueous solutions of the alkalis, forming salts which have the character of soaps. A number of the metallic salts of the acid have been prepared and analysed. They are of the types CjgHg^OgM', (CigHgj02)2M, and (C^gH3j02)gM' respectively, but in the case of the potassium salts an acid salt having the formula CigH3j02K,2CjgHg202 is formed, besides the normal salt, C^gHg^OgK. Such acid potassium salts of monobasic acids are also known in the cases of palmitic and stearic acids.
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