Imidazo[2,1-b][1,3,4]thiadiazoles are synthesized from the 2,4-dinitro benzoic acid and thiosemicarbazide. Their reaction with phenacyl (p-substituted phenacyl) bromides led to formation of the respective imidazolthadiazole derivative. . The structure of the above compounds was confirmed from their spectral characteristics. Some of these compounds were found to possess slight to moderate activity against the microorganisms Staphylococcus aureus, Candida albicans, Pseudomonas aeruginosa, and Escherichia coli.