3'-Modified oligodeoxyribonucleotides for the study of 2-deoxyribose damage in DNA.

Well-defined substrates for the study of oxidative processes are important for the elucidation of the role of DNA damage in the etiology of diseases such as cancer. We have synthesized 3'-modified oligodeoxyribonucleotides (ODNs) using 5'→3' 'reverse' DNA synthesis for the study of 2-deoxyribose oxidative damage to DNA. The modified monomers designed for these studies all share a common feature, they lack the naturally occurring 3'-hydroxyl group found in 2-deoxyribonucleosides. Modified H-phosphonates containing 3'-phenyl selenides as well as saturated and unsaturated sugars were obtained and incorporated in ODNs. These ODNs were used to investigate the fate of C3'-dideoxyribonucleotide radicals in DNA.