The constituents of leptandra / by Frederick B. Power and Harold Rogerson.

  • Power, Frederick B. (Frederick Belding), 1853-1927.
Date:
1910
Catalogue details

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: The constituents of leptandra / 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.

    5/16 (page 1946)
    1940 Distillation of the Extract with Steam. Separation of an Essential Oil. A quantity (2 kilograms) of the above-mentioned extract was mixed with water, and steam passed through the mixture for sevoral hours. The distillate, which amounted to about 6 litres, contained some oily drops floating on the surface. It was thoroughly extracted with ether, the ethereal liquid being dried and the solvent removed, when 0'9 gram of an essential oil was obtained. The yield of the latter was thus equivalent to 0'16 per cent, of the weight of the drug. This essential oil, when distilled under diminished pressure, passed over between 120° and 160°/25 mm. It was a dark brown, mobile liquid, possessing a strong, persistent odour, and gave no coloration with ferric chloride. Non-volatile Constituents of the Extract. After the distillation of the extract with steam, as above described, there remained in the distillation flask a dark-coloured, aqueous liquid (A), and a quantity of a dark brown resin (B). B These products, when cold, were separated by filtration, and the resin repeatedly washed with hot water until nothing further was removed, the washings being added to the aqueous liquid. Examination of the Aqueous Liquid (A). Isolation of 3: 4-Dimethoxycinnamic Acid, C0H3(OMe)2-CH:CH-CO2H. The aqueous liquid was repeatedly extracted with ether, and the combined ethereal extracts evaporated to a small volume. On cooling, a quantity (5'0 grams) of a crystalline substance separated. This was removed by filtration, dried, and recrystallised from water, when it separated in yellow needles, melting at about 170°, but after repeated crystallisation from absolute alcohol it was obtained in large, colourless needles, melting at 180—181°. (Found, C = 63’4; H = 5-9; OMe = 29'2. Calc., C = 63’5; H = 58; OMe = 29 8 per cent.) The substance was found to be an acid, and is seen to agree in its (characters and composition with 3: 4-dimethoxycinnamic acid, ^eHa(0Me)2,CH.CH*C02H. When mixed with a portion of the latter, as obtained by the methylation of ferulic acid (Trans., 1907, 91, 893), the melting point was unchanged. Further confirmation of the identity of the acid was obtained by the preparation of its Uncthyl ester, which separated from absolute alcohol in small ^tiisms, melting at G4°. So far as known to us, this is the first