Chemical examination of the root of Ipomoea orizabensis / by Frederick B. Power and Harold Rogerson.

  • Frederick Belding Power
Date:
1912
Catalogue details

Licence: In copyright

Credit: Chemical examination of the root of Ipomoea orizabensis / by Frederick B. Power and Harold Rogerson. 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.

    14/32 (page 10)
    acetate and dilute alcohol. The substance was thus obtained in handsome, pearly leaflets, melting at 135—136°, and it gave the colour reaction of the phytosterols: 0 3192, on heating at 110°, lost 0-0153 IT20. 11,0 = 4-8. 0-1072 * gave 0 3292 C02 and 01144 II20. 0 = 83 7; 11 = 11-8. C27H40O,H2O requires H20 = 4-5 per cent. -C27lI40O requires 0 = 839; H = 1T9 per cent. A determination of the specific rotatory power gave the following result: 0T934,* made up to 20 c.c. with chloroform, gave oD —0-39' in a 2-dcm. tube, whence [a]D —33-6°. The acetyl derivative was prepared by heating a little of the substance with acetic anhydride. It separated in flat needles, melting at 122—124°. The above-described substance was thus definitely identified as a phytosterol, and, with the exception of the slightly higher melting point of its acetate, it agrees in character with verosterol (Trans., 1910, 97, 1951). Isolation of Cetyl A Icohol, CjgH^O. The alcoholic mother liquors remaining from the separation of the above-described phytosterol were evaporated, and the residue distilled under diminished pressure. The distillate was’ collected in three fractions, which passed over respectively at 190—200°, 200—220°, and 220—300°/15 mm. The first two fractions were united and recrystallised, first from light petroleum and then from ethyl acetate. A quantity (25 grams) of cetyl alcohol was thus obtained, which separated in small, colourless leaflets, melting at 50—51°. (Found, C = 79’0; H = 140. Calc., C = 793; H = 14T per cent.) The third of the above-mentioned fractions, which was very small in amount, was crystallised from ethyl acetate, when it separated in laminae, melting at 55—56°. It apparently consisted of a mixture of cetyl alcohol and some higher alcohol of that series. The alkaline liquid, from which the above-described products had been removed by extraction with ether, was acidified, and again extracted with ether. The ethereal liquid was first shaken with aqueous ammonium carbonate, which removed a small amount (1-0 gram) of the previously-described 3 :4-dihydroxycinnamic acid (m. p. 222—225°). It was next extracted with a solution of sodium carbonate, which removed all of the dissolved substance. The * Auhydvous substauce.