title: Pyrimidinone: versatile Trojan horse in DNA photodamage?
abstract: (6-4) Photolesions between adjacent pyrimidine DNA bases are prone to secondary photochemistry. It has been shown that singlet excited (6-4) moieties form Dewar valence isomers as well as triplet excitations. We here report on the triplet state of a minimal model for the (6-4) photolesion, 1-methyl-2(1H)-pyrimidinone. Emphasis is laid on its ability to abstract hydrogen atoms from alcohols and carbohydrates. Steady-state and time-resolved experiments consistently yield bimolecular rate constants of ∼10(4) M(-1) s(-1) for the hydrogen abstraction. The process also occurs intramolecularly as experiments on zebularine (1-(β-d-ribofuranosyl)-2(1H)-pyrimidinone) show.
authors.affiliation: Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätstr. 1, D-40225 Düsseldorf, Germany. gilch@hhu.de.
authors.forename: Mathias
authors.initials: M
authors.lastname: Micheel
authors.forename: Christian
authors.initials: C
authors.lastname: Torres Ziegenbein
authors.forename: Peter
authors.initials: P
authors.lastname: Gilch
authors.forename: Gerald
authors.initials: G
authors.lastname: Ryseck
mesh_terms: D003562:Cytidine / Q000031:analogs & derivatives / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D004249:DNA Damage / Q000528:radiation effects*; D006859:Hydrogen / Q000737:chemistry; D008027:Light / Q000009:adverse effects*; D000432:Methanol / Q000737:chemistry; D015394:Molecular Structure; D055668:Photochemical Processes; D011744:Pyrimidinones / Q000737:chemistry*; D013057:Spectrum Analysis; D014867:Water / Q000737:chemistry
chemical_list: D011744:Pyrimidinones; D014867:Water; D003562:Cytidine; C009131:pyrimidin-2-one beta-ribofuranoside; D006859:Hydrogen; D004247:DNA; D000432:Methanol