Photo-induced formation of the 2-deoxyribonolactone-containing nucleotide for d(ApCpA); effects of neighboring bases and modification of deoxycytidine.

Previously, we reported the formation of a 2-deoxyribonolactone-containing nucleotide by UV irradiation of d(ApCpA). In this paper, we report some mechanical feature of this novel photoreaction. From the results of photolysis of d(GpCpG), this reaction is independent of neighboring bases. On photolysis of deoxycytidine at acidic pH, 2-deoxyribonolactone was produced with 74.2% isolated yield. And effects of some modifications of deoxycytidine were investigated. The results suggest that hydrates are possible intermediates for this reaction and the protonation may be essential not for deoxycytidine, but for the intermediates.