Synthesis of 3-nitrobenzo[a]pyrene bay-region trans-7,8-diol anti-9,10-epoxide and the corresponding N2-deoxyguanosine adduct.

3-Nitrobenzo[a]pyrene (3-nitro-BaP) is a potent mutagenic environmental contaminant, and its biological activities have been intensively studied. It is significant to prepare its reactive metabolites and the corresponding modified DNA adducts for biological studies. The synthesis of its oxidized proximate metabolite trans-7,8-dihydro-3-nitrobenzo[a]pyrene (3-nitro-BaP-trans-7,8-dihydrodiol, 1), its oxidized ultimate metabolite trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydro-3- nitrobenzo[a]pyrene (3-nitro-BaP-DE, 2), and the corresponding DNA adduct 10-(deoxyguanosin-N2-yl)-7,8,9-trihydroxy-7,8,9,10-tetrahydro-3- nitrobenzo[a]pyrene is described.