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Photochemical generation and reactivity of the major hydroxyl radical adduct of thymidine.

ABSTRACT: 5,6-Dihydro-5-hydroxythymidin-6-yl radical (1), the major reactive intermediate resulting from hydroxyl radical addition to C5 of the pyrimidine, is produced via 350 nm photolysis of a 2,5-dimethoxyphenylsulfide precursor (2). Competition between O(2) and thiol for 1 suggests that the radical reacts relatively slowly with ?-mercaptoethanol compared to other alkyl radicals. Overall, aryl sulfide 2 should be an effective precursor for the major hydroxyl radical adduct of thymidine in DNA.

SUBMITTER: San Pedro JM

PROVIDER: S-EPMC3366351 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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Photochemical generation and reactivity of the major hydroxyl radical adduct of thymidine.

San Pedro Joanna Maria N JM Greenberg Marc M MM

Organic letters 20120522 11

5,6-Dihydro-5-hydroxythymidin-6-yl radical (1), the major reactive intermediate resulting from hydroxyl radical addition to C5 of the pyrimidine, is produced via 350 nm photolysis of a 2,5-dimethoxyphenylsulfide precursor (2). Competition between O(2) and thiol for 1 suggests that the radical reacts relatively slowly with β-mercaptoethanol compared to other alkyl radicals. Overall, aryl sulfide 2 should be an effective precursor for the major hydroxyl radical adduct of thymidine in DNA. ...[more]

PMID: 22616940

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