In selective recovery of Vinblastine (I), Vinleurosine (II) and Vincristine (or their acid addition salts) from Virca rosea L by (a) extracting with aq. methanol, (b) evaporating the extract free of methanol, (c) acidifying the soln., (d) extracting with water-immiscible solvent, (e) rendering the alkaloid-contg. aq. phase alkaline, (f) extracting the alkaloids with water-immiscible organic solvent, (g) evaporating to dryness and (h) recovering the alkaloids by chromatography with partially deactivated Al2O3; leaching is effected with neutral methanol, the alkaloid mixture from (g) is dissolved in ethanol contg. is not 10% acid, the alkaloids are crystallised as acid addition salts and, after filtering, the salt mixture (either as acid salt or free base obtd. with alkali) is chromatographed on Al2O3 partly deactivated with water and fractionally eluting.
展开▼
