Synthesis and Biological Activity of [5-(Arylmethylideneamino)-1,3,4-thiadiazol-2-yl]thioacetanilides

Sixteen novel derivatives of [5-(arylmethylideneamino)-1,3,4-thiadiazol-2-yl]thioacetanilide were synthesized by the reaction of S-alkylation of 5-arylmethylideneamino-2-mercapto-1,3,4-thiadiazole with chloroacetanilides under the conditions of solid-liquid phase transfer catalysis using PEG-400 as a phase transfer catalyst in the presence of potassium carbonate. All the products were characterized by elemental analysis, FT-IR, H-1 NMR and C-13 NMR spectra. The preliminary biological activity tests showed that some of the title compounds had obvious regulating activities for the growth of wheat, and some compounds such as 4a and 4e possessed satisfactory activity of growth inhibition against B. subtilis at a test concentration (20 mg/mL).