Furazans and furazan oxides. Part VI. New furazano[3,4-d]pyrimidine N-oxides: preparation and structure

Abstract

Some new furazano[3,4-d]pyrimidine N-oxides have been prepared. The tautomerism of the furazan oxide ring favours 1-oxide structures, to the virtual exclusion of the 3-oxides. Some tetrazolopyrimidine intermediates underwent hydrolytic cleavage of the pyrimidine ring, leading to tetrazole derivatives.