A reevaluation of the ambident reactivity of the guanine moiety towards hydroxyl radicals.

ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy.
Angewandte Chemie International Edition (Impact Factor: 11.34). 03/2009; 48(12):2214-7. DOI: 10.1002/anie.200805372
Source: PubMed

ABSTRACT Radically different: Contrary to previous proposals, the main reaction of the HO(*) radical with guanosine or 2'-deoxyguanosine is the hydrogen abstraction from the NH(2) moiety to give a guanyl radical. This radical, characterized by a broad band in the visible region (around 610 nm), undergoes tautomerization to the most stable isomer.

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