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

  • Frederick Belding Power
Date:
[1910?]
Catalogue details

Licence: In copyright

Credit: The constituents of leptandra / by Frederick B. Power and Harold Rogerson. Source: Wellcome Collection.

    14/18 (page 1955)
    The portion of the extract which was soluble in water contained 3: 4-dimethoxycinnamic acid, a quantity of mannitol, amounting to 2'14 per cent, of the weight of the drug, and a sugar which yielded d-phenylglucosazone (m. p. 209—211°), together with some tannic and colouring matter. It yielded, furthermore, a quantity of a brown, amorphous product, which possessed an intensely bitter, nauseous taste, and amounted to 1'6 per cent, of the weight of the drug. By the hydrolysis of this product there were obtained, besides resinous material, cinnamic and 2?-methoxycinnamic acids. The portion of the extract which was insoluble in water consisted chiefly of a dark brown resin, which amounted to 6*2 per cent, of the weight of the drug. From this resin the following substances were obtained: A phytosterol, C27H460 (m. p. 135—136°; [a]D — 33’0°), which it is proposed to designate verosterol; a mix¬ ture of fatty acids, consisting apparently of oleic, linolic, palmitic, and stearic acids; p-methoxycinnamic acid, which was present in the form of an ester; and a very small amount of 3: 4-dimethoxy¬ cinnamic acid, which had probably been occluded by the resin. It has been observed that ^-methoxycinnamic acid, when melted, passes into a “ liquid-crystalline ” phase, which persists until a temperature of 181—182° is reached. It has not been possible to confirm the statement recorded in the literature that “ leptandra ” contains a crystalline, bitter glucoside, designated as “ leptandrin,” to which its activity may be attributed. Steinmann (Amer. J. Pharm., 1887, 59, 229) obtained from “ leptandra/’ in an amount of about O'l per cent., a crystalline, yellow substance, which possessed a very bitter taste, and was found not to be a glucoside, although it was not further characterised. From the method by which this substance was isolated, it appears highly probable that it consisted of 3: 4-di¬ methoxycinnamic acid, contaminated with a little of the above- mentioned, bitter, amorphous product. The fact that an aqueous solution of this product froths strongly on agitation has doubtless led to the statement recorded in the literature that “ leptandra ” contains saponin. Some tests with preparations of “ leptandra,” which were kindly conducted for us by Dr. H. H. Dale, Director of the Wellcome Physiological Research Laboratories, led to the following conclusions. Both the crude resin and the bitter, amorphous product obtained from the portion of the alcoholic extract which was soluble in water were administered by the mouth to dogs, in doses of 1 gram each, but without any visible effect. The bitter, amorphous product was also tested on the mammal by intravenous injection, and on the isolated mammalian heart, but no characteristic action could be c