Direct resolution of mono- and diol enantiomers of unsubstituted and methyl-substituted benz[a]anthracene and benzo[a]pyrene by high-performance liquid chromatography with a chiral stationary phase.

The direct resolution of 86 structurally related monomethyl, mono-ol, and trans- and cis-diol enantiomers of unsubstituted and methyl-substituted benz[a]anthracene and benzo[a]pyrene was investigated by high-performance liquid chromatography with a commercially available column, packed with an (R)-N-(3,5-dinitrobenzoyl)phenylglycine, ionically bonded to gamma-aminopropylsilanized silica. The results indicate that structural factors, such as conformation, presence of a methyl substituent, molecular size and shape, and ring saturation all contribute to chiral interactions between the chiral stationary phase and the solutes. Detailed chiral recognition mechanisms can not yet be established, due to complex structural factors that influence enantiomeric resolutions and the lack of data on the absolute configurations of the resolved enantiomers. Nevertheless, the chromatographic method can be applied to the determination of enantiomeric purity of mono- and diol metabolites of polycyclic aromatic hydrocarbons. The absolute configurations of a limited number of resolved enantiomers have been established.