The reaction of 4-acetyl-3-hydroxy-2-propylbenzyl chloride (I) with 2,5-dimercapto-1,3,4-thiadiazole (II) in 2-butanone gives 2-[(4-acetyl-3-hydroxy-2-propylbenzyl)thio]-5-mercapto-1,3,4-thiadiazole (III), which is condensed with alpha-bromo-p-toluic acid (IV) in 2-butanone.