Improved process for the preparation of active glucosides from digitalis lanata

摘要

506,465. Glucosides. CHINOIN GYOGYSZER ES VEGYESZETI TERMEKEK GYARA R. T. (DR. KERESZTY & DR. WOLF), and WOLF, E. June 24, 1938, No. 18848. [Class 2 (iii)] Glucosides of digitalis lanata, which retain their acetyl groups, are prepared by kneading the leaves or dry extracts thereof with magnesium oxide in the presence of a little water and extracting the mass with organic solvents such as ethyl acetate or acetone. The leaves are preferably pretreated with benzene or other hydrocarbon solvents, whilst the dry extracts thereof are obtained by the use of aqueous acetone, aqueous ethyl acetate or a mixture of ethyl acetate and diluted alcohol. The evaporated residue of the extraction following the magnesia treatment is dissolved in strongly diluted alcohol and the solution shaken with ether; the glucosides crystallize out from the aqueous alcoholic layer and may be purified by recrystallization from, say, methylethyl ketone or aqueous dioxane. Examples are given. British Specification 357,926 and German Specifications- 383,480, 427,274, and 514,096 are referred to.