Abstract
Photochemical precursors that produce dA(•) and dG(N(2)-H)(•) are needed to investigate their reactivity. The synthesis of two 1,1-diphenylhydrazines (1, 2) and their use as photochemical sources of dA(•) and dG(N(2)-H)(•) is presented. Trapping studies indicate production of these radicals with good fidelity, and 1 was incorporated into an oligonucleotide via solid-phase synthesis. Cyclic voltammetric studies show that reduction potentials of 1 and 2 are lower than those of widely used "hole sinks", e.g., 8-oxodGuo and 7-deazadGuo, to investigate DNA-hole transfer processes. These molecules could be useful (a) as sources of dA(•) and dG(N(2)-H)(•) at specific sites in oligonucleotides and (b) as "hole sinks" for the study of DNA-hole transfer processes.