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.
10/26 page 564
![possess essentially the same structure, the only difference being in the length of the side chain. This proved to be the case, for, on oxidation in alkaline solution with an excess of potassium permanganate, hydno- carpic acid yielded n-decanedicarboxylic acid, [CH2]10*(CO2H)2, and a tricarboxylic acid, C16H2806 (m. p. 60°), which is considered to be n-tridecane-aa'y-tricarboxylic acid, CO2H-[CH2]2*CH(CO2H)*[CH2]10*CO2H. The following formulae may therefore be ascribed to hydnocarpic acid : CH CH CH[CH2]10-CO2H ch2-ch2 1 - a-Carboxy-n-decyl-A4- cyclopentene. \-u-Carboxy-n-decyl-\ : 4-bicyclo'pentane. These may be expressed, as in the case of chaulmoogric acid, by one formula, as follows: CH CH-H^ C[CH2]10*CO2H. CH2-CH2 Experimental. I. Chaulmoogric Acid, C18H3202. The chaulmoogric acid employed in this investigation was prepared from genuine chaulmoogra oil (from the seeds of Taraktogenos Kurzii, King). The oil was hydrolysed with alcoholic potash, the acids liberated, fractionally crystallised from alcohol, and the chaulmoogric acid finally purified by distillation under diminished pressure and recrystallisation from alcohol (compare Trans., 1904, 85, 846). It was then obtained in colourless, glistening leaflets, and, when freshly dis¬ tilled, melted at bS’fi0, and had [a]D +62*1° in chloroform solution. After keeping for some time the optical rotatory power of the acid becomes somewhat diminished and it acquires a slightly yellow colour. If it be then again distilled, a dark brown substance is left in the dis¬ tilling flask, which is probably formed by polymerisation. Oxidation of Chaulmoogric Acid in Alkaline Solution with Potassium Permanganate (0 — 2—3 Atomic Equivalents).—One hundred grams of chaulmoogric acid were dissolved in a solution of 50 grams of potassium hydroxide in 5 litres of water, and to this were added 5 litres of a 2 per cent, solution of permanganate, the temperature being kept between 16° and 20°. The whole of the permanganate was instantly reduced. After filtering, the liquid was made nearly neutral with sulphuric acid, and concentrated to a small bulk. The acids were then liberated, asd](https://iiif.wellcomecollection.org/image/b30611751_0010.jp2/full/800%2C/0/default.jpg)
