Abstract The cyclization of 5-amino-3-methylthiopyrazole-4-carbonitriles or 4-carboxamides 3a-j, which were prepared by the reaction of ketene dithioacetals 1a, b [1a: bis ( methylthiomethylenemalononitrile; 1b: bis (methylthio) methylenecyanoacetamide] with hydrazines (hydrazine hydrate, phenylhydrazine, p-chlorophenylhydrazine, p- nitrophenylhydrazine), with formamide or carbon disulfide proceeded to give the ...