The constitution of chaulmoogric and hydnocarpic acids / by Marmaduke Barrowcliff and Frederick B. Power.

  • Barrowcliff, Marmaduke.
Date:
[1907]
Catalogue details

Licence: In copyright

Credit: The constitution of chaulmoogric and hydnocarpic acids / by Marmaduke Barrowcliff and Frederick B. Power. Source: Wellcome Collection.

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    0-1151 gave 0-2835 C02 and 0-1065 H20. C = 67-2; 11=10*3. 0-0955 „ 0-2358 C02 „ 0*0886 H20. C = 67-3; H = 10-3. 13341 in 100 benzene gave A£-0T5°. M.W. = 436. ^16^30^4 requires C = 67*1 ; H = 10*5 per cent. M.W. = 286. C24H44°6 » C = 67-3; H=10-3 „ M.W. = 428. Propyl Ester.—This was obtained as a viscid, colourless oil, which boiled at 302°/24 mm. : 0-1159 gave 0-2916 C02 and 0-1108 H20. C = 68-6; H=10*6. 0-1331 „ 0-3360 C02 „ 0-1278 H20. C = 68*8; H = 10*7. C18H3404 requires C = 68-8 ; H=10'8 per cent. C27H50O6 „ C = 68-9; H = 10-6 „ From these results it is evident that the fraction boiling at 260—270°/15 mm. consists essentially of the trimethyl ester of a tricarboxylic acid having the formula C18H3206, and, from considera¬ tions which are discussed in the introductory portion of this paper, it is seen that this acid is n-pentadeccme-aa'y-tricarboxylic acid. n-Pentadecane-aa/y-tricarboxylic acid is very soluble in alcohol, ether, chloroform, or ethyl acetate, moderately so in benzene, and insoluble in water. It is an exceedingly stable substance. When heated with concentrated nitric acid it dissolved, but separated unchanged on cooling. When warmed with an alkaline solution of permanganate it was only very slowly attacked at temperatures below 70J. When, however, it was treated at this temperature with an excess of permanganate, it yielded succinic acid. Attempts were made to obtain a hydroxy-acid or lactone by oxidising with limited quantities of permanganate, but most of the acid was recovered unchanged. It is unattacked by a chromic acid mixture, a fact which is probably due to the insolubility of the organic acid in water. When treated with chromic acid in acetic acid solution, the greater portion was recovered unchanged, and no other definite product could be isolated. An attempt was also made to obtain from the acid an unsaturated compound. For this purpose it was brominated by the V olhard method, and the elements of hydrogen bromide subsequently eliminated, but the results were of a negative character. Fraction 270—280°/15 mm.—This was small in amount, and consisted to a large extent of the ester of the above-mentioned tricarboxylic acid. For the more complete examination of the lower acids formed by the oxidation of chaulmoogric acid, another portion was treated in alkali solution with permanganate, as previously described. After removing the excess of permanganate, and filtering, the liquid was made neutral with sulphuric acid and evaporated to dryness. The mixture of
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