2-Amino-5-(1-phenyl-3-methyl-5-chloropyrazol-4-yl)-1,3,4-thiodiazole (1) has been prepared by the reaction of 1-phenyl-3-methyl-5-chloropyrazol-4-carboxylic acid with aminothiourea in the presence of phosphorus oxychloride. Then a series of novel 1-[(un)substituted benzoyl]-3-[5-(1-phenyl-3-methyl-5- chloropyrazole-4-yl)-1,3,4-thiadiazol-2-yl]-thioureas (3a～3j) have been synthe-sized by the reaction of compound 1 with (un)substituted benzoyl isothiocyanates (2) by means of ultrasonic radiation heating method and ordinary method. The structures of these compounds were confirmed by elemental analysis, IR and ¹H NMR spectra.

Key words: (un)substituted benzoylthiourea, ultrasonic radiation, 1,3,4-thiodiazole, synthesis, pyrazole