The constitution of chaulmoogric and hydnocarpic acids / by Marmaduke Barrowcliff and Frederick B. Power.
- Barrowcliff, Marmaduke.
- Date:
- [1907]
Licence: In copyright
Credit: The constitution of chaulmoogric and hydnocarpic acids / by Marmaduke Barrowcliff and Frederick B. Power. Source: Wellcome Collection.
12/26 page 566
![0-3360 gram in 100 c.c. of chloroform gave aD +0°5' in a 2-dcm. tube, whence [a]D + 12*4°. The ester was hydrolysed and the acid extracted and crystallised from ethyl acetate, in which it was readily soluble. It separated in clusters of small, silky needles, melting at 105°: 0-0944 gave 0*2368 C02 and 0*0922 H20. C = 68*4 ; H = 10‘8. Ci8H3404 requires C = 68’8 ; H = 10*8 per cent. 0‘5008 gram in 100 c.c. of alsolute alcohol gave aD + 0°7' in a 2-dcm. tube, whence [a]D +1T6°. This acid is thus shown to be a dihydroxydihydrochaulmoogric acid, and was found to be identical with the acid of the same composition described in the previous communication, the melting point of which was given as 102° (Trans., 1904, 85, 860). The mother liquors from the crystallisation of the ester melting at 75—76° were found to be leevorotatory, and from them an ester was isolated which, after several crystallisations, melted at 68—69°. This ester crystallised in silky needles, and was much more soluble in methyl alcohol than the one of higher melting point which was pre¬ viously isolated : 0-8420 gram in 100 c.c. of chloroform gave aD — 0°16' in a 2-dcm. tube, whence [a]D - 15 *8°. On hydrolysing this ester an acid was obtained which, after two crystallisations from ethyl acetate, melted at 92—93° : 0-1004 gave 0-2520 C02 and 0-0986 H20. C = 68*5 ; H = 10-9. Ci8H3202(0H)2 requires C = 68*8 ; H= 10-8 per cent. 0-2936 gram in 25 c.c. of absolute alcohol gave aD - 0°20' in a 2-dcm. tube, whence [a]D - 14-2°. This acid is therefore an isomeride of that melting at 105°, but it is much more sparingly soluble in ethyl acetate than the latter. Both these acids yield sodium salts which are only sparingly soluble in cold water. Fraction 275—290°/16 mm.—This evidently also contained some of the two dihydroxydihydrochaulmoogric acids which were isolated from the preceding fraction. Oxidation of Chaulmoogric Acid in Alkaline Solution with Potassium Permanganate (0 = 4 Atomic Equivalents).—One hundred grams of chaulmoogric acid were dissolved in the same amount of solution of potassium hydroxide as in the preceding experiment, and to this was added a solution of 150 grams of potassium permanganate in 8 litres of water, the temperature of the mixture being kept at 15—18°. The acids were extracted, converted into their methyl esters, and frac¬ tionally distilled under a pressure of 15 mm. Several fractions were](https://iiif.wellcomecollection.org/image/b30611751_0012.jp2/full/800%2C/0/default.jpg)
