A convenient method was established for the synthesis of some new 6,7-dihydro-2-(methylthio)-5-
aminopyrazolo[1,5-a]pyrimidine-3-carbonitriles 4 and -[1,2,4]triazolo[1,5-a]pyrimidin-5-amines 5 from β-
cyanohydrazines 3 and suitable ketene dithioketals 2-[bis(methylthio)methylene]propanedinitrile 1 and dimethyl Ncyanocarbonimidodithioate
2, respectively in good yields. The structure of the title compound was characterized by IR,
EA, 1H- and 13C-NMR.