Abstract Several new 2, 5-disubstituted derivatives of 1, 3, 4-thiadiazoles containing imine moiety were obtained from cyclization of thiosemicarbazide and corresponding p-substituted carboxylic acid in phosphorus oxychloride then the resulted products were reacted with salicylaldehyde to give the final products 3a-h. All the newly synthesized compounds were characterized using FTIR, 1H NMR, 13C NMR and elemental analysis. All compounds ...