Cerium(IV)-mediated oxidation of flavonol with relevance to flavonol 2,4-dioxygenase. Direct evidence for spin delocalization in the flavonoxy radical

József Kaizer; Ildikó Ganszky; Gábor Speier; Antal Rockenbauer; László Korecz; Michel Giorgi; Marius Réglier; Serge Antonczak

doi:10.1016/j.jinorgbio.2007.02.005

Cerium(IV)-mediated oxidation of flavonol with relevance to flavonol 2,4-dioxygenase. Direct evidence for spin delocalization in the flavonoxy radical

J Inorg Biochem. 2007 Jun;101(6):893-9. doi: 10.1016/j.jinorgbio.2007.02.005. Epub 2007 Feb 21.

Authors

József Kaizer¹, Ildikó Ganszky, Gábor Speier, Antal Rockenbauer, László Korecz, Michel Giorgi, Marius Réglier, Serge Antonczak

Affiliation

¹ Department of Organic Chemistry, University of Pannonia, 8201 Veszprém, Hungary.

PMID: 17408749
DOI: 10.1016/j.jinorgbio.2007.02.005

Abstract

The cerium(IV)-mediated oxidation of 3-hydroxy-4'-methylflavone (1) proceeds by H-atom abstraction forming the flavonoxy radical (7), and the subsequent combination of its resonance forms leads to the 3-hydroxy-4'-methylflavone dehydro dimer (9). The above system serves as direct evidence for the intermediacy of the flavonoxy radical, its spin delocalization, and also indirect evidence for valence tautomerism as a key step on the substrate activation both in the quercetinase and its biomimic model system.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cerium / chemistry*
Crystallography, X-Ray
Dioxygenases / chemistry*
Flavonols / chemistry*
Models, Molecular
Oxidation-Reduction
Spin Labels

Substances

Flavonols
Spin Labels
Cerium
Dioxygenases
flavonol 2,4-dioxygenase