title: Formation of an antibacterial metabolite from a new macrolide compound 23-O-benzyl-5-mycaminosyl-tylonolide (TMC-101), by a hepatic microsomal drug-metabolizing enzyme system.
abstract: Upon incubation of 23-O-benzyl-5-mycaminosyl-tylonolide (TMC-101) with liver microsomes in the presence of an nicotinamide adenine dinucleotide phosphate-generating system, at least four metabolites were formed: two of them were also formed by an enzyme(s) in rat serum. One of the metabolites formed by liver microsomes possessed antibacterial activity comparable to TMC-101 as examined by bioautography using Micrococcus luteus ATCC 9341 as a tester strain. Incubation of TMC-101 with rat serum degraded most of the parent compound and did not form the active metabolite. The capacity of liver microsomes to produce the active metabolite was increased by pretreatment of rats with 3-methylcholanthrene, phenobarbital and polychlorinated biphenyl. The metabolite with the antibacterial activity was estimated not to be formed by the N-demethylation of TMC-101, and was chemically unstable.
authors.affiliation: Division of Analytical Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Nakura
authors.forename: H
authors.initials: H
authors.lastname: Ohi
authors.forename: T
authors.initials: T
authors.lastname: Miura
authors.forename: T
authors.initials: T
authors.lastname: Fujiwara
authors.forename: H
authors.initials: H
authors.lastname: Ishizone
authors.forename: T
authors.initials: T
authors.lastname: Yokoi
authors.forename: M
authors.initials: M
authors.lastname: Kitada
authors.forename: T
authors.initials: T
authors.lastname: Kamataki
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D006027:Glycosides / Q000378:metabolism*; D008297:Male; D008837:Micrococcus / Q000187:drug effects; D008862:Microsomes, Liver / Q000201:enzymology*; D009249:NADP / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D015645:Tylosin / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D006027:Glycosides; D009249:NADP; C073717:23-O-benzyl-5-mycaminosyl-tylonolide; D015645:Tylosin