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cascarillineЗначение термина cascarilline в knolikcascarilline - Cascarilline cascarilline - Cascarilline may be prepared from the bark of Croton Cascarilla or C. Eleutheria by the following processes: (1) The bark is exhausted with coldwater by percolation, precipitated with lead acetate, and the filtrate treated with sulphuretted hydrogen; the filtered liquid, after agitation with animal charcoal, and filtration, is gently evaporated to dryness. The powder is re-dissolved in boiling alcohol, and crystallised by very slow or spontaneous evaporation. (Duval.) (2) A quantity of coarsely powdered cascarilla bark is covered with a 2 to 3 per cent, solution of oxalic acid and allowed to stand for 12 hours, the mixture being frequently shaken. At the expiration of this period, the temperature of the mixture is gradually raised to-140° F. (60° C.), after which it is allowed to cool. Lastly, the liquid is filtered and the marc well pressed. The filtrate is then saturated with ammonia, and evaporated at a low temperature to ⅔ of its bulk. The liquid is again allowed to cool, and a deposit separates, if any has been formed. The liquid is poured into a flask containing pure ether, the whole being shaken for some time. After being allowed to stand for 3 hours or more, the ethereal solution is poured off and distilled, so as to recover the greater part of the ether. The evaporation is completed spontaneously in a current of air, with out the application of heat, the result being pure white Cascarilline. The ethereal solution contains a small quantity of essential oil, nearly the whole of which passes over during the process of distillation; but this in no way prevents the ether from being used for the separation of another batch of the alkaloid. Рядом со словом cascarilline в knolik
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