Laccase from Basidiomycetous Fungus Catalyzes the Synthesis of Substituted 5‐Deaza‐10‐oxaflavins <i>via</i> a Domino Reaction

Abstract

Abstract magnified image The present investigation provides a simple and convenient route for the synthesis of substituted 5‐deaza‐10‐oxaflavins owing to their importance as probable redox coenzymes. The reaction of α,β‐unsaturated derivatives of barbituric acid and dimedone with catechol or 1,4‐hydroquinones was catalyzed using laccase in aqueous medium. Quinones, generated in situ by the oxidation of the corresponding catechol or 1,4‐hydroquinones, underwent a domino reaction with chalcones to produce 5‐deaza‐10‐oxaflavins and tetrahydroxanthen‐1‐ones.