The constituents of commercial chrysarobin / by Frank Tutin and Hubert W.B. Clewer.

  • Tutin, Frank.
Date:
1912
Catalogue details

Licence: In copyright

Credit: The constituents of commercial chrysarobin / by Frank Tutin and Hubert W.B. Clewer. 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.

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    As a preliminary experiment, 10 grams of the Araroba powder were extracted successively in a Soxhlet apparatus with various solvents, when the following amounts of extract, dried at 110° were obtained: Petroleum (b. p. 35—50*) extracted 3 73 giams = 37*3 per cent. Ether „ 1-28 = 128 „ Chloroform 0-27 = 27 Ethyl acetate ,, 0T4 a = 1-4 „ Alcohol „ 0-33 if = 33 „ Total = 5*75 grams = 57 *5 per cent. The portion of the material left undissolved by this treatment (42'5 per cent.) consisted of dark-coloured, gummy matter and inorganic substances. A quantity (1 kilogram) of the Araroba powder was completely extracted by continuous percolation with hot alcohol, and from the resulting extract the greater part of the alcohol was removed. The residue was then mixed with water, and distilled in a current of steam, but nothing appreciable was removed by this treatment. The mixture remaining in the distillation flask consisted of a yellowish-brown, finely divided solid and a brown, aqueous liquid. These products were separated by filtration, and the solid washed and dried, after which it weighed 510 grams. The aqueous filtrate and washings were thoroughly examined, but they yielded only a trace of emodin monomethyl ether (m. p. 197°), some brown, amorphous material, and a small amount of a sugar which gave rf-phenylglucosazone (m. p. 209°). No tannin was present. The above-mentioned solid, which had been separated from the aqueous liquid, was mixed with purified sawdust, and submitted to a very thorough extraction in a large Soxhlet apparatus with petroleum (b. p. 35—50°), ether, chloroform, ethyl acetate, and alcohol. Examination of the Petroleum Extract. The petroleum extract of the solid consisted, for the most part, of a very sparingly soluble, orange-red powder, which amounted to 420 grams. The petroleum solution was decanted from it, and evaporated, -when 2 grams of residue were obtained. This product on examination was found to consist chiefly of the anthraquinone derivatives subsequently to be described, but it also yielded a small amount of the higher fatty acids, together with a trace of a substance which appeared to be a hydrocarbon. Isolation of Emodin, CisHioOs- The above-mentioned, orange-red coloured solid, which was very sparingly soluble in petroleum, was dissolved in 2 litres of chloro-
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