Chemical examination of Aethusa cynapium / by Frederick B. Power and Frank Tutin.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1905]
Catalogue details

Licence: In copyright

Credit: Chemical examination of Aethusa cynapium / by Frederick B. Power and Frank Tutin. Source: Wellcome Collection.

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    substance which, after recrystallization, melted at 1920 C. and gave the color reaction of protocatechuic acid. (B) Examination of the Aqueous Liquid.—The aqueous liquid which was separated from the resinous matter after the distilla¬ tion of the original alcoholic extract with steam, as previously described, was of a very dark brown color. It was concentrated to a thick syrup on the water-bath, then mixed with prepared sawdust, the mixture completely dried in a vacuum desiccator, and extracted in a Soxhlet apparatus with alcohol. This extract was concentrated and allowed to stand for some time, when a considerable quantity of a crystalline substance slowly separated, which was collected by filtration at the pump, washed with alcohol, and recrystallized from dilute alcohol. It was thus obtained in colorless needles, and was found to consist of an organic substance associated with potassium nitrate and chloride, from which it was impossible to free it by recrystallization. In order to isolate the organic compound, the possibility of its being an alcohol was considered, and the following method was there¬ fore adopted. It was boiled for about five minutes with an excess of acetic anhydride and a little anhydrous sodium acetate, and the liquid, after being allowed to cool, shaken with a con¬ siderable quantity of water. A crystalline substance was thus precipitated, which was collected by filtration at the pump, washed with water, dissolved in hot alcohol, and allowed to crystallize. It then formed octahedral crystals, which melted at 122-1230 C., and this melting-point was not changed by further crystallization; it was also recovered unchanged when again boiled with acetic anhydride for half an hour. When heated at 1150 C. it did not lose in weight. 0.1025 gram gave 0.1875 gram C02 and 0.0568 gram H20. C = 49.9; H = 6.i. C18H26012 requires 0 = 49.8; H = 6.o per cent. 0.4949 gram dissolved in 25 cc. of chloroform, gave a:D + o°.52' in a 2 dcm. tube, whence [a]D + 2i.9°. The acetylated product thus agreed in composition with an hexaacetyl derivative of an hexahydric alcohol, which was evidently mannitol. For the purpose of comparison some hexa- acetyl-d-mannitol was prepared from pure d-mannitol. Aftes recrystallization from alcohol, it melted at i22-i23°C., not ar 1190 C., as has been stated,1 and a mixture of equal parts of thit 1 Beilstein’s “Handbuch der organischert Chemie,” Bd. I, p. 417.