Like other furazano [3, 4-d] pyrimidines which have been studied, 3~~,~ the 7-&oxy compounds 5 and 6, and also 8-10, suffered ready hydrogenolysis of the furazan ring when stirred with a palladized charcoal catalyst in methanol or aqueous methanol solution under an atmosphere of hydrogen (Scheme 11). The resulting 6-alkoxy-2, 4, 5-triaminopyrimidines were labile to air in the form of their free bases. Compounds 14-16, however, were ...