Chemical examination of Ornithogalum thyrsoides / by Frederick B. Power and Harold Rogerson.

  • Frederick Belding Power
Date:
[1910]
Catalogue details

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: Chemical examination of Ornithogalum thyrsoides / 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.

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    green, fatty solid, floating on the surface. It was extracted with ether, when, on evaporation of the solvent, 4 Gm. of a product were obtained, which was purified by distillation under 15 Mm pressure. When subsequently dissolved in ethyl acetate, it was obtained in colourless laminae, melting at 59-60°. 0-1770 gave 0'4856 CO2 and 0-2042H.20. C = 74-8; H = 12-8, CieHsaOa requires 0 = 75 0; H = 12‘5 per cent. The above product was thus identified as palmitic acid. II. Ether Extract. Isolation of Ipuranol, CasHssOzlOH)^. This extract, after the complete removal of the solvent, formed a dark green solid, and amounted to 24'2 Gm. Its ethereal solution, on standing, deposited a quantity (4'7 Gm.) of a dark green substance, which was collected on a filter. This substance was subsequently brought into a Soxhlet apparatus, and extracted with absolute alcohol, when a quantity of green, resinous material was quickly removed. On continuing the extraction with a fresh portion of alcohol, a light coloured) sparingly soluble solid was slowly taken out. The latter was purified by crystallisation from dilute pyridine, from which it separated in small rosettes of microscopic needles, melting at 285-290°. 0-1028 gave 0-2726 COa and 0-0968 HaO. C = 72-3; H = 10-5 C23H40O4 requires 0 = 72-6; H = 105 per cent. This substance yielded a colour reaction similar to that pro- duced by the phytosterols, and was identified as ipuranol, C28H880a(0H)2 {Amer. Journ. Pharm., 1908, 80, 264, 576; Journ. Chem. Soc., 1908, 93, 907 ; 1909, 95, 249; 1910, 97, 7). When boiled with acetic anhydride it yielded diacetylipuranol, C28H8804(C0-CH8)2, which separated in leaflets melting at 162°. The specific rotatory power of ipuranol and of its acetyl deriva- tive not having previously been ascertained, and the amount of material at present available having been sufficient for this purpose, these determinations have now been made, with the following results:— 0-2150 of ipuranol, dissolved in 20 C.c. of pure pyridine, gave ao —0° 24' in a 1 Dcm. tube, whence [a]D —37-2°. 0-0982 of diacetylipuranol, dissolved in 20 C c. of ethyl acetate, gave ao—0’ 15' in a 2 Dcm. tube, whence [a]D —25-4°. The green, resinous material which was separated from the ipuranol by means of alcohol, as mentioned above, was only