Research on mechanisms in chemical carcinogenesis often requires authentic monomeric carcinogen-DNA adducts. Few adducts are commercially available, and individuals often obtain submilligram levels of adducts from carcinogen-treated DNA; this may be insufficient for their needs. The objective of this project is to determine the feasibility of developing generic approaches to gram-scale synthesis of carcinogen-DNA adducts which may be used in modern molecular toxicology studies: as postlabelling or chromatography standards; in developing immunoassays; or for incorporation into oligonucleotides. This project will specifically address preparation of 3'-monophosphates of major adducts of dG and dA with 7-bromomethyl-12- methylbenzanthracene (BMBA) or benzo(a)pyrene diol-epoxide I (BPDE), as standards for the 32p-postlabelling assay. Silylation vs acylation will be evaluated for transient protection of BPDE and deoxyribose hydroxyls; their stability during phosphorylation and ease of selective removal will be checked. O-silylated or -acylated amines (from ammoniation of BPDE or BMBA) will be condensed with the appropriate protected halopurine nucleoside to yield fully blocked N2-dG or n6-dA derivatives. Phosphorylation will follow selective removal of the 3'-protecting group. Commercially available monomeric carcinogen-DNA adducts will facilitate chemical carcinogenesis research.
