Synthesis of Some New 1,3,4-Thiadiazole Derivatives and studying their Biological Activities

Abstract

2-amino-1,3,4-thiadiazole-5-thiol have been prepared by heating thiosemicarbazide with carbon disulphide and anhydrous sodium carbonate in absolute ethanol. This product was treated with substituted benzyl halides, then treated with chloro acetyl chloride in dry benzene to yield 5-substituted benzyl thio-2-chloroacetamido-1,3,4- thiadiazole. Several new [5-substituted benzyl thio(2-thiadiazolyl)-carbamoyl] methyl dithio carbanilates have been prepared by condensing the ammonium salt of aryl dithiocarbamic acid with 5- substituted benzyl thio-2-chloroacetamido-1,3,4-thiadiazoles in dry acetone. 2-amino-5-substituted benzyl thio-1,3,4-thiodiazole was prepared by heating 2-amino-5-substituted benzyl thio-1,3,4-thiadiazole with substituted benzyl halide. Treatment with p-hydroxybenzaldehyd gave the corresponding Shiff bases. The synthesized compounds have been characterized on the basis of IR spectral analysis and the results were compatible with their assigned structures. The synthesized compounds (b2,b3,c4,d1,d3) were tested against five types of bacteria (Staphylococcus aureusBacillussubtilis, Klebsiella pneumonia, Proteus vulgaris, Escherichia coli,),the compounds (b3,d3( showed expected biological activity.