title: Identification of hepatic metabolites of two highly carcinogenic polycyclic aza-aromatic compounds, 7,9-dimethylbenz[c]acridine and 7,10-dimethylbenz[c]acridine.
abstract: The hepatic microsomal metabolites of the highly carcinogenic dimethylbenzacridines, 7,9-dimethylbenz[c]acridine (7,9-DMBAC), and 7,10-dimethylbenz[c]acridine (7,10-DMBAC) were obtained with preparations from 3-methylcholanthrene-pretreated rats. Metabolites were separated by reversed-phase HPLC and characterized using UV spectral data and chemical ionization-mass spectrometry after trimethylsilylation and GC. Comparisons with products formed in the presence of the epoxide hydrolase inhibitor, 1,1,1-trichloropropane 2,3-oxide and with those formed from the three synthetic alcohol derivatives of each parent compound, aided the assignment of firm or tentative structures to 16 products from 7,9-DMBAC found in 22 reversed-phase chromatographic peaks, and for 17 products of 7,10-DMBAC found in 19 chromatographic peaks. The more abundant metabolites were derived from oxidation of the methyl groups. Other metabolites were dihydrodiols, epoxides, phenols and secondary metabolites. The 9-methyl group prevented dihydrodiol formation at the 8,9-position from 7,9-DMBAC, and for each carcinogen, the 3,4-dihydrodiol was formed. As well, 3,4-dihydrodiols of methyl oxidized compounds were found.
authors.affiliation: Department of Pharmacy, University of Sydney, NSW, Australia.
authors.forename: Y
authors.initials: Y
authors.lastname: Ye
authors.forename: C C
authors.initials: CC
authors.lastname: Duke
authors.forename: G M
authors.initials: GM
authors.lastname: Holder
mesh_terms: D000166:Acridines / Q000378:metabolism*; D000438:Alcohols / Q000378:metabolism; D000818:Animals; D002273:Carcinogens / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D008862:Microsomes, Liver / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000166:Acridines; D000438:Alcohols; D002273:Carcinogens; C010123:7,10-dimethylbenz(c)acridine; C031753:7,9-dimethylbenz(c)acridine