title: Microbial transformation of bufotalin by Alternaria alternata AS 3.4578.
abstract: The microbial transformation of a cytotoxic bufadienolide, bufotalin (1), was carried out. Three transformed products from 1 by Alternaria alternata were isolated. Their structures were characterized as 3-keto-bufotalin (2), 12 beta-hydroxyl-bufotalin (3), and 3-keto-12 beta-hydroxyl-bufotalin (4) based on the extensive NMR studies. Among them, 3 and 4 were new compounds with strong in vitro cytotoxic activities against HeLa cells.
authors.affiliation: The State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100083, China.
authors.forename: Xiu-Lan
authors.initials: XL
authors.lastname: Xin
authors.forename: Li-Bin
authors.initials: LB
authors.lastname: Zhan
authors.forename: Feng-Yun
authors.initials: FY
authors.lastname: Li
authors.forename: Xiao-Chi
authors.initials: XC
authors.lastname: Ma
authors.forename: Ke-Xin
authors.initials: KX
authors.lastname: Liu
authors.forename: Jian
authors.initials: J
authors.lastname: Han
authors.forename: De-An
authors.initials: DA
authors.lastname: Guo
mesh_terms: D000528:Alternaria / Q000378:metabolism*; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001711:Biotransformation; D002018:Bufanolides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D002018:Bufanolides; C004600:bufotalin