Deconvoluting the reactivity of two intermediates formed from modified pyrimidines.
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ABSTRACT:
SUBMITTER: Weng L
PROVIDER: S-EPMC3830933 | biostudies-literature | 2013 Jul
REPOSITORIES: biostudies-literature
Publications
Deconvoluting the reactivity of two intermediates formed from modified pyrimidines.
Weng Liwei L Horvat Sonia M SM Schiesser Carl H CH Greenberg Marc M MM
Organic letters 20130703 14
Generation of the 5-(2'-deoxyuridinyl)methyl radical (6) was reexamined. Trapping by 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl confirms that 6 is generated. However, trapping by methoxyamine reveals that the respective carbocation (10) is also produced. Examining the effects of these traps on products in DNA reveals that the carbocation and not 6 yields interstrand cross-links. Cross-link formation from the carbocation is consistent with DFT calculations that predict that addition at the N1 ...[more]
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