Synthesis and catalytic properties of 5-deazaflavo-6,9-quinones

Abstract

Novel 5-deazaflavo-6,9-quinones, which can be regarded as chemical hybrids of 5-deazaflavin and coenzyme Q, were designed and synthesized in a search for more powerful autorecycling redox catalysts for amine oxidation. 9-Methoxy-5-deazaflavins, which were synthesized from 6-aminouracils and 2,3-dimethoxybenzaldehydes, were exposed to oxidation with cerium ammonium nitrate in aqueous acetonitrile to give 5-deazaflavo-6,9-quinones. While 8-unsubstituted 5-deazaflavo-6,9-quinones thus obtained were unstable in the amine oxidation, 8-methoxy-5-deazaflavo-6,9-quinones were rather stable under the same conditions and showed an autorecycling amine-oxidizing ability.