2-arylhydrazono-3-oxopropanals in heterocyclic synthesis: Synthesis of arylazopyrazole, arylazoisoxazole and dialkylpyridazine-5,6-dicarboxylate derivatives. New one-step synthesis of arylazopyrimidines.

A novel synthesis of arylpyrazole, isoxazole, dialkyl 1,6-dihydropyridazine 5,6-dicarboxylate derivatives and a new one-step synthesis of azolopyrimidines under microwave-assisted conditions are reported.