The constituents of the leaves of Prunus serotina / by Frederick B. Power and Charles W. Moore.

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

Licence: Attribution 4.0 International (CC BY 4.0)

Credit: The constituents of the leaves of Prunus serotina / by Frederick B. Power and Charles W. Moore. 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.

    14/23 (page 1103)
    Nine grams of the mixed acids were converted into their lead salts, and the latter digested with ether, when the greater portion dissolved. Both the soluble and insoluble portions were decom- posed by hydrochloric acid, and the regenerated fatty acids purified by distillation under diminished pressure. The soluble portion of the lead salts yielded 6 grams of liquid acids, whilst the insoluble portion gave 2'5 grams of solid acids. The Liquid Acids.—These acids, when distilled under diminished pressure, passed over at about 230°/12 mm. An analysis and a determination of the iodine value gave the following results: 0-1232 gave 0’3490 C02 and 0’1255 H20. C = 77’2; H = 11’3. 0'2190 absorbed 0’4337 iodine. Iodine value=198‘0. C]8H3202 requires C = 77T ; H = 1T4 per cent. Iodine value = 181 4. CjgHsoOo „ C = 77'7; H = 10‘8 „ Iodine value = 274‘0. In order to obtain more definite information respecting the nature of the above mixture, a quantity of it was oxidised according to the method described by Lewkowitsch (Chemical Technology and Analysis of Oils, Fats, and Waxes, 1904, vol. I, p. 360). This resulted in the formation of tetrahydroxystearic acid (m. p. 157—160°) and a very small quantity of a hexahydroxystearic acid, melting at 170—172°. It may thus be concluded that the liquid acids consisted chiefly of a mixture of linolic and fsolinolenic acids, the former in predominating amount. The Solid Acids.—These acids melted at 53—55°, and on analysis gave the following result: 0-1564 gave 0‘4305 C02 and 0’1750 II20. C = 751; H = 12‘4. C10H32O2 requires C = 75‘0; H = 12-5 per cent. C18Hm02 „ C = 761; H = 127 From this result it would appear that the solid acids consisted of a mixture of palmitic and stearic acids, the former predominating. Ethereal Extract of the Resin. This extract, after the complete removal of the solvent, amounted to <0 grams. As originally obtained, it consisted of a dark green, ethereal liquid, containing a quantity of an amorphous, green, spaiingly soluble powder. The latter was collected on a filter, and washed well with ether, when it amounted to about 35 grams. On concentrating the ethereal filtrate to about 500 c.c., a further quantity (7 grams) of a similar amorphous powder was obtained.