Synthesis and study of a 6-amino-5-oxo-3H,5H-uracil and derivatives. The structure of an intermediate proposed in mechanisms of flavin and pterin oxygenases
Treatment of isoalloxazine 5-oxides with acetic anhydride yielded the corresponding 8-acetoxyisoalloxazines exclusively, which are labile to hydrolysis to give 8-hydroxyisoalloxazines (8-hydroxyflavins).