Synthesis and properties of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines. 15. Ring opening in imidazo[4,5-d]-1,2,3-triazines

It has been shown that 4-methylthio-, ethoxy-, and methoxyimidazotriazines and imidazotriazin-4-ones, unlike benzo-1,2,3-triazines, do not display cryptodiazonium behavior. A novel type of fission of the triazine ring to give esters and thioesters of 5-aminoimidazole-4-carboxylic acid is described.For Communication 14, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1248–1250, September, 1989.