Synthesis and antimicrobial activity of some newer biphenyl imidazo [2,1-b] [1,3,4] thiadiazole derivatives.

In the present study, we have reported the synthesis of some novel heterocyclic derivatives comprising imidazole and 1,3,4-thiadiazole containing moiety. Imidazothiadiazoles are of interest because of their diverse biological activities and clinical applications. Reactions of biphenyl carboxylic acid with thiosemicarbazide in the presence of phosphorous oxychloride resulted in biphenyl containing 2-amino-1,3,4-thiadiazole which is then further subjected to condensation with α-bromoarylketone under reflux in dry ethanol. The structures of the newly synthesised compounds were characterized by various spectral techniques and screened for antibacterial activity against strains of Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis, and antifungal activity against Candida albicans, Saccharomyces cerevisiae and Aspergillus niger. The compounds exhibited moderate to good activity when compared with standards.