Microbial transformations of natural antitumor agents. 9. O-Demethylation of 9-methoxyellipticine.

Microbial transformation studies were conducted with 9-methoxyellipticine (1). Several microorganisms including Botrytis allii (NRRL 2502), Cunninghamella echinulata (NRRL 1386), C. echinulata (NRRL 3655), and Penicillium Brevicompactum (ATCC 10418) achieved O-demethylation of (1) in good yield. P. brevicompactum was used to prepare 9-hydroxyellipticine (4) from 1 for isolation and complete identification. High-performance liquid chromatography was used to verify the identity of the major metabolite (4) in other cultures.