Vinca rosea alkaloids - vinblastine, vinleurosine and vincristine selective isolation

摘要

Vinblastine (I), vinleurosine (II) and vincristine (III) or their salts, known cytostatic agents, are recovered in improved yields from Vinca rosea L by (a) extracting with neutral aqs. methanol, (b) dissolving the alkaloid mixture obtained in a known manner from the extract in ethanol contg. is not 10% acid and crystallising (I)-(III) from the ethanol soln. in the form of their acid addition salts; (c) chromatographing the mixture of acid addition salts, opt. after conversion into the free bases, on Al2O3 partially deactivated with water and fractionally eluting, and (d) recovering (I)-(III) or their acid addition salts from the eluate fractions and purifying them if required. The process involves less phase interchanges than prior methods and the chromatographic separation is less complicated.