Process for purifying 20(S)-camptothecin

摘要

A process for purifying 20(S)-camptothecin, the process comprising:(a) combining an aqueous base and a starting material containing 20(S)-camptothecin to convert the lactone ring of the 20(S)-camptothecin into a carboxylate salt;(b) hydrogenating to the product of step (a) in the presence of a transition metal catalyst;(c) acidifying the aqueous phase of the product of step (b) to form 20(S)-camptothecin crystals;(d) adding at least one polar aprotic solvent to the product of step (c); and(e) separating off the purified 20(S)-camptothecin crystals.