Carbocations from oxidized metabolites of benzo[a]anthracene: a computational study of their methylated and fluorinated derivatives and guanine adducts.

ABSTRACT: Structure-reactivity relationships and substituent effects on carbocation stability in benzo[a]anthracene (BA) derivatives have been studied computationally at the B3LYP/6-31G and MP2/6-31G levels. Bay-region carbocations are formed by O-protonation of the 1,2-epoxides in barrierless processes. This process is energetically more favored as compared to carbocation generation via zwitterion formation/O-protonation, via single electron oxidation to generate a radical cation, or via benzylic hydroxylation. Relative carbocation stabilities were determined in the gas phase and in water as solvent (PCM method). Charge delocalization mode in the BA carbocation framework was deduced from NPA-derived changes in charges, and substitution by methyl or fluorine was studied at different positions select

SUBMITTER: Borosky GL 

PROVIDER: S-EPMC2538532 | biostudies-literature | 2006 Jul

REPOSITORIES: biostudies-literature