Process for preparing the alkaloids referred to as theirosidine and theirocristine, by extracting plants of the family Apocynaceae.

摘要

The invention comprises the alkaloids leurocristine and leurosidine, their acid addition and quaternary ammonium salts, and their preparation by contacting plant material of the family Apocynaceae, for example Vinca rosea, with an aqueous acid and a water-immiscible organic solvent, separating the organic layer, extracting it with aqueous acid, making the extract alkaline, extracting it with a water-immiscible solvent, separating the alkolids therefrom by chromatography, obtaining the fraction containing leurocristric and/or leurosidine by preferential elution, evaporating this fraction to dryness, and recovering the desired alkaloid therefrom by crystallization either in the form of a free base or as an acid addition salt. Subsequent quaternization is effected by standard methods. Catharanthine, vindoline, ajalicine, vindolinine dihydrochloride, vincaleukoblastine sulphate and virosine are obtained as by-products from the chromatographic separation. The alkaloids and salts of the invention are employed in the treatment of malignancies and may be used in combination with physiologically compatible extending medium in form suitable for oral or parenteral administration.