The interaction of amidrazones and isocyanate esters in dimethylformamide produces good yields of 4-substituted-1-imidoylsemicarbazides. They are unaffected by acids, but are cyclised to 3-alkyl (or aryl)-1, 2, 4-triazol-3-ones or their 4-substituted analogues in alkaline media. Analogous linear adducts arising in good yields from amidrazones and ethoxycarbonyl isothiocyanates are cyclised to 3-substituted 5-ethoxycarbonamido-1, 3, 4- ...
![[N'-(2-phenyl-acetimidoyl)-hydrazinothiocarbonyl]-carbamic acid ethyl ester Structure](https://image.chemsrc.com/caspic/296/62441-40-1.png)
