SYNTHESIS OF 2H-CHROMENOPYRIMIDINE-2,4(3H)-DIONES (5-DEAZA-10-OXAFLAVINS) AS AN AUTORECYCLING OXIDIZING AGENT

Article abstract of DOI:10.1246/cl.1980.1157

Treatment of 3-methyl-6-phenoxyuracils with the Vilsmeier reagent gave the corresponding 5-formyl-3-methyl-6-phenoxyuracils.Dehydrative cyclization of the above 5-formyluracils with polyphosphoric acid gave 3-methyl-2H-chromeno<2,3-d>pyrimidine-2,4(3H)-diones (3-methyl-5-deaza-10-oxaflavins).These 5-deaza-10-oxaflavins showed strong oxidizing power in oxidizing benzyl alcohol even under neutral conditions to give benzaldehyde, while they were hydrogenated to 1,5-dihydro-5-deaza-10-oxaflavins.