Thymine addition to ethanol: induction by gamma irradiation.

When thymine in dilute, deaerated, aqueous solution was irradiated with gamma-rays in the presence of ethanol, a high yield of products containing both the thymine and ethanol moieties was obtained. These were shown to be isomers formed by the attack of CH(3)CHOH radicals at the carbon No. 6 position of thymine. A similar reaction was observed with N, N'-dimethylthymine, but O,O'-dimethylthymine did not react. The reaction may be relevant to the resistance of certain cells to ionizing radiation.