The constitution of chaulmoogric acid : Pt. 1 / by Frederick B. Power and Frank H. Gornall.

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

Licence: In copyright

Credit: The constitution of chaulmoogric acid : Pt. 1 / by Frederick B. Power and Frank H. Gornall. Source: Wellcome Collection.

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    unstable. A portion which had been exposed in a vacuum desiccator over paraffin wax was analysed: 0*3270 gave 0*2546 AgBr. Br = 33'l. 0*2634 „ 0*2050 AgBr. Br = 33*l. C20H36O2Br2 requires Br = 34*l per cent. Bromodihydrochaulmoogric Acid, Cl7H32Br*C02H. Chaulmoogric acid (8*5 grams) was gently warmed in 25 c.c of a 68 per cent, solution of hydrogen bromide in glacial acetic acid, the mixture being maintained at 40—50° for about five minutes. On cooling, the liquid formed two layers, and the uppermost, which became solid, was accordingly separated, thoroughly washed with water, and finally dried on a porous plate; it was optically inactive, melted at 36—38°, and was shown by analysis to be bromodihydrochaulmoogric acid. 0*2102 gave 0*1040 AgBr. Br = 21*0 C18H3302Br requires Br = 22*2 per cent. Action of Sodium and Amyl Alcohol on Chaulmoogric Acid. The Formation of Chaulmoogryl Alcohol, C1SH33*0H, and Chaulmoogryl Chaulmoograte, Cl7H31 • C02* C18H33. Thirty grams of chaulmoogric acid were dissolved in 750 c.c. of amyl alcohol and the solution boiled ; six grams of sodium were then introduced, and the liquid vigorously heated until the metal had all dissolved. The solution was then acidified with sulphuric acid, well shaken, and the aqueous acid layer removed. The amyl-alcoholic solution was then washed several times with water, and again vigorously boiled and treated with a further 6 grams of sodium. This entire process was repeated six times. The amyl-alcoholic solu¬ tion from the last treatment with sodium, after having been acidified with sulphuric acid and subsequently washed with water, was distilled in order to remove the greater part of the amyl alcohol. The remainder of the latter was eliminated by distillation in steam. The residue, which contained a supernatant layer, was extracted with ether, the ethereal solution being washed, dried, and the solvent removed. The product was then fractionally distilled under 18 mm. pressure, when the following fractions were obtained : (1) below 244° (a small amount); (2) 244—254° (15 grams); (3) 254—354° (1—2 grams); (4) 354—358° (5 grams). All these fractions became crystal¬ line on cooling.