Reactivity of 2′-deoxyuridin-1′-yl radical in various DNA structures

DNA C1' radicals formed by hydrogen atom abstraction from the C1' position of the sugar backbone lead to the production of 2'-deoxyribonolactone as a DNA damage lesion. Although DNA C1' radicals may be involved in a variety of DNA damage processes, there is very little information on the molecular basis of DNA structure dependence in the reactions of C1' radicals. Here, we describe a detailed study of the reactivity of 2'-deoxyuridin-1'-yl radicals in single- and double-stranded B-form DNA and G-quartets in the formation of 2'-deoxyribonolactone, using the unnatural precursor 1'-pivaloyl-2'-deoxyuridine (1).