title: Microbial transformations of natural antitumor agents. 23. Conversion of withaferin-A to 12 beta- and 15 beta-hydroxy derivatives of withaferin-A.
abstract: Microbial transformation experiments were conducted with the antitumor lactone withaferin-A. Cunninghamella elegans NRRL 1393 transformed withaferin-A (1a) to 15 beta-hydroxywithaferin-A (2a) and 12 beta-hydroxy-withaferin-A (3a). The hydroxylated metabolites were isolated by solvent extraction and were purified by column and thin-layer chromatography. Structures of the hydroxylated metabolites were determined by proton-and carbon-13 NMR, IR and mass spectral analyses, and by the preparation of acylated derivatives. Compounds 2a and 3a inhibited the growth and biochemical functions of in vitro grown P-388 lymphocytic leukemic cells.
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000378:metabolism*; D001711:Biotransformation; D004875:Ergosterol / Q000031:analogs & derivatives* / Q000378:metabolism; D005285:Fermentation; D007941:Leukemia P388 / Q000188:drug therapy; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D009090:Mucorales / Q000378:metabolism*; D054358:Withanolides
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D054358:Withanolides; C009684:withaferin A; D004875:Ergosterol