Nitrosative Cyclization of 1, 3-Dimethyl-6-(α-methylalkylidenehydrazino)-uracils by Means of N-Nitrosodimethylamine-Phosphorus Oxychloride Mixture. A New Route to 2-Vinyl-v-triazolo [4, 5-d] pyrimidines

Abstract

A new synthetic method of 2-vinyl-v-triazolo [4, 5-d] pyrimidines, which consists of the nitrosative cyclization of 1, 3-dimethyl-6-(α-methylalkylidenehydrazino) uracils with a mixture of N-nitrosodimethylamine and phosphorus oxychloride (NDA+POCl₃) is described. The reaction of 1, 3-dimethyl-6-hydrazino-5-nitrosouracil with acetophenone gave 1, 3-dimethyl-6-phenyl-7-azalumazine (3-phenylfervenulin) (X). The nitrosation of 6-benzylidenehydrazino-1, 3-dimethyluracil with NDA+POCl₃ also gave X.