Carbonate radical anion as an efficient reactive oxygen species: Its reaction with guanyl radical and formation of 8-oxoguanine

► Reactions of four guanine radicals with carbonate radical anion were studied. ► This is the first theoretical study of this problem. ► Density functional, MP2 theories and polarizable continuum model were employed. ► Water molecules catalyze the reactions by facilitating proton transfer. ► Role of the solvent medium used in experiments is critically evaluated.