RT Journal Article SR Electronic T1 Biotransformation of 6-Methoxy-3-(3′,4′,5′-trimethoxy-benzoyl)-1H-indole (BPR0L075), a Novel Antimicrotubule Agent, by Mouse, Rat, Dog, and Human Liver Microsomes JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 1042 OP 1049 DO 10.1124/dmd.106.014597 VO 35 IS 7 A1 Hsien-Tsung Yao A1 Yu-Shan Wu A1 Yi-Wei Chang A1 Hsing-Pang Hsieh A1 Wei-Cheng Chen A1 Shih-Jung Lan A1 Chiung-Tong Chen A1 Yu-Sheng Chao A1 Ling Chang A1 Hsu-Yi Sun A1 Teng-Kuang Yeh YR 2007 UL http://dmd.aspetjournals.org/content/35/7/1042.abstract AB 6-Methoxy-3-(3′,4′,5′-trimethoxy-benzoyl)-1H-indole (BPR0L075) is a novel synthetic indole compound with microtubule binding activity. Incubation of BPR0L075 with mouse, rat, dog, and human liver microsomes in the presence of NADPH resulted in the formation of six metabolites. Liquid chromatography-tandem mass spectrometry and comparison with the synthetic reference standards identified two metabolites (M1 and M5) as the products derived from hydroxylation on the indole moiety of the molecule. M3 was also identified as a product derived from hydroxylation, but the structure of this metabolite was not identified because of the lack of a reference standard. M2, M4, and M6 were identified as the products derived from O-demethylation. M2, 6-desmethyl-BPR0L075, was the major metabolite formed by the liver microsomes of the four species. No qualitative species difference in the metabolism of BPR0L075 was observed. There was quantitative species difference in the metabolism of BPR0L075 among the four species. Whereas mouse and rat liver microsomes metabolized BPR0L075 predominantly via O-demethylation, dog liver microsomes metabolized BPR0L075 by O-demethylation and hydroxylation to about the same extent. The rank order of intrinsic clearance rates for the conversion of BPR0L075 to 6-desmethyl-BPR0L075 was mouse > rat > human > dog. Incubation of BPR0L075 with baculovirus-insect cell-expressed human cytochrome P450 (P450) isozymes showed that CYP1A2, 2C9, 2C19, 2D6, 2E1, and 3A4 all catalyzed the O-demethylation and hydroxylation of BPR0L075 but to a different degree. Among the six P450 isozymes tested, CYP1A2 and 2D6 were most active on catalyzing the metabolism of BPR0L075. CYP1A2 catalyzed mainly the formation of M1, M2, and M3. M2 was the predominant metabolite formed by CYP2D6. The American Society for Pharmacology and Experimental Therapeutics