Radiolysis of pyrimidines in aqueous solutions. Part 1.—Product formation in the interaction of e –aq, ·H, ·OH and Cl –2· with thymine

Abstract

Product yields in the reaction of e^–_aq, ·H, ·OH and Cl^–₂· with thymine and those in the reaction of e^–_aq and ·OH/O^–· with thymine^– have been determined quantitatively in ⁶⁰Co γ-irradiated aqueous thymine solutions in the presence of suitable scavengers. Good material balances between G(– thymine) and G(total products) have been obtained in all cases. The products determined were: thymine dimers, cis-thymine glycol, trans-thymine glycol, 5-hydroxydihydrothymine, 6-hydroxydihydrothymine, dihydrothymine, 5-hydroperoxydihydrothymine, 5-hydroxymethyluracil, 5-hydroxy-5-methylbarbituric acid, formylpyruvylurea, acetylurea, urea, and alcohol adducts. Based on the yields of these products and the available literature, mechanisms are proposed and discussed.