Synthesis and characterization of the oxidized dGTP lesions spiroiminodihydantoin-2'-deoxynucleoside-5'- triphosphate and guanidinohydantoin-2'-deoxynucleoside-5'- triphosphate

Two convenient synthetic routes to the oxidized guanosine triphosphate lesions spiroiminodihydantoin-2'-deoxynucleoside-5'-triphosphate (dSpTP) and guanidinohydantoin-2'-deoxynucleoside-5'-triphosphate (dGhTP) are reported. Both two-electron oxidation of 2'-deoxy-7,8-dihydro-8-oxoguanosine-5'-triphosphate (dOGTP) using SO4*- generated photolytically from K2S2O8 or four-electron oxidation of 2'-deoxyguanosine-5'-triphosphate (dGTP) from singlet oxygen provide either dSpTP or dGhTP at pH 8.0 or 4.4, respectively. Highly purified triphosphates are obtained by ion pair reversed-phase HPLC.