The constituents of the leaves and stems of Davesia latifolia / by Frederick Belding Power and Arthur Henry Salway.

  • Frederick Belding Power
Date:
1914.]
Catalogue details

Licence: Public Domain Mark

Credit: The constituents of the leaves and stems of Davesia latifolia / by Frederick Belding Power and Arthur Henry Salway. Source: Wellcome Collection.

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    0-0972 gave 0-2680 CO, and 0-1106 II20. C = 75’2; H = 126. Neutralisation value = 211. CjgHggOg requires C = 76T; H = 127 per cent. N.Y. = 197*5. C1GH3202 „ C = 75*0; H = 12*5 „ „ N.Y. = 219-1. The above results indicate the solid acids to have been a mixture of palmitic and stearic acids. Ethereal Extract of the Resin. * This extract, when free from solvent, formed a dark green, viscid mass. It was digested with ether, when a portion of it (28 grams) was found to be sparingly soluble. The sparingly soluble material was collected, dissolved in a small quantity of alcohol, and the solution kept for some time, when a crystalline sub¬ stance was slowly deposited. The latter, when recrystallised from water, separated in colourless needles, melting at 146—147°, and was found to be identical with the dibenzoylglucoxylose previously isolated from the original aqueous liquid (4). The alcoholic mother liquor remaining from the first crystallisation of the above- mentioned compound evidently still contained a considerable quantity of it, for, on heating with an alkali hydroxide, benzoic acid and a sugar were formed, and no other definite product could be isolated. The portion of the ethereal extract of the resin which was readily soluble in ether was extracted successively with aqueous ammonium carbonate and sodium hydroxide. The first-mentioned alkali removed about 5 grams of benzoic acid, whilst the sodium hydroxide extract, on acidification, yielded a considerable quantity of dark-coloured, resinous material, from which nothing definite, except benzoic acid, could be isolated. After extraction with alkalis, the ethereal liquid was washed, dried, and the solvent removed. A residue was thus obtained, which, bv treatment with petroleum of high boiling point, yielded a small quantity of myricyl alcohol, melting at 81—82°. Chloroform, Ethyl Acetate, and Alcohol Extracts of the Resin. These extracts were small in amount, and formed dark-coloured, viscid products, which possessed a bitter taste. They were separately heated in dilute alcoholic solution with sulphuric acid, when each of them was found to yield both benzoic acid and a reducing sugar, thus indicating the presence of some of the previously-described dibenzoylglucoxylose. The last-mentioned compound, melting at 146—147°, was, moreover, directly isolated from the ethyl acetate extract of the resin by dissolving it in a
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