efficient synthesis of some 1,4-disubstituted thiosemicarbazide derivatives is described. The reaction of 3-chlorobenzoic acid hydrazide with various aryl isothiocyanates gave thiosemicarbazide derivatives (1–11) in good yield. The cyclization of compounds (1–11) in the presence of 2% NaOH resulted in the formation of compounds (12–22) containing the 1,2,4-triazole ring. A series of newMannichbases (23–33)