Abstract Arylhydrazonomalononitriles 1a, b react with phenylhydrazine to yield amidrazones 2a, b that cyclize to give 2-aryl-5-phenylhydrazono-2, 5-dihydro-[1, 2, 4]-triazine-6- carbonitriles 5a, b upon reaction with dimethylformamide dimethylacetal (DMFDMA). Refluxing 5a, b in glacial acetic acid resulted in the formation of the pyrazolo-1, 2, 4-triazines 6a, b. Compounds 6a, b were also formed upon treatment of 3-amino-4-phenylhydrazono- ...