Metabolic conversion of dibenz[a,h]anthracene (+/-)trans-1,2-dihydrodiol and chrysene (+/-)trans-3,4-dihydrodiol to vicinal dihydrodiol epoxides.

The hydroxyl groups of dibenz[a,h]anthracene trans-1,2-dihydrodiol and chrysene trans-3,4-dihydrodiol are known to be predominantly in quasi-axial conformations. These dihydrodiols were metabolized by liver microsomes from 3-methylcholanthrene-pretreated rats to form 1,2,3,4-tetrahydrotetrols as the major products. The major metabolites of the dihydrodiols were isolated by reversed-phase high-performance liquid chromatography and identified by ultraviolet--visible absorption and mass spectral analyses. The results indicate that axial hydroxyl groups of dibenz[a,h]anthracene trans-1,2-dihydrodiol and of chrysene trans-3,4-dihydrodiol do not direct metabolism away from their respective vicinal double bond.