Abstract Treatment of methyl α-(dimethylarninomethyleneamino) carboxylates 1 (from α- amino acids and dimethylformamide dimethylacetal) with hydrazine gives 5-substituted-4, 5- dihydro-1, 2, 4-triazin-6-ones 2, which are smoothly dehydrogenated to 5-substituted-1, 2, 4- triazin-6-ones 3 with potassium permanganate in acetone/acetic acid.
