PREPARATION, CHARACTERIZATION AND P-32 POSTLABELING OF BUTADIENE MONOEPOXIDE N-6-ADENINE ADDUCTS

Butadiene monoepoxide, an active metabolite of 1,3-butadiene, was reac ted with deoxyadenosine, deoxyadenosine 3'-monophosphate and DNA, The nucleoside reaction products were isolated and using various spectrosc opic techniques were determined to be the N-6-substituted deoxyadenosi ne adducts. Deoxyadenosine 3'-monophosphate products were identified b y treating the modified nucleotide products with alkaline phosphatase, resulting in nucleoside adducts with HPLC retention times similar to those of the deoxyadenosine adducts, Monophosphate products were also identified through MS/MS techniques by comparing the daughter ions der ived from the base moieties of N-6-alkylated nucleosides and nucleotid es. The reaction mechanism in aqueous solution was studied using optic ally active butadiene monoepoxides, Using the alkylated monophosphate standards and an HPLC/P-32 postlabeling assay the N-6-alkylated adenin e adducts were detected in calf thymus DNA exposed to butadiene monoep oxide.