LAUSR

Some novel azo-1,3,4-thiadiazole derivatives were greenly synthesized by the reaction of terephthalic acid with thiosemicarbazide in the presence of phosphorus oxychloride (POCl3) under ultrasonic irradiation forming1,4-bis(2-amino-1,3,4-thiadiazol-5-yl) benzene. The later was diazotized with different substituted phenols to give 1,4-bis(2-substituted phenyldiazenyl-1,3,4-thiadiazol-5-yl) benzene (1-8).The structures of the compounds synthesized identified by using spectral analysis methods (F.T-IR, 1H-NMR and 13C-NMR).The compounds (1-8) tested for their anti-microbial (Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa) activities using disc diffusion method. The minimum inhibitory concentrations (MICs) of the compounds also calculated by agar streak dilution method. The compounds (6) was the most active compound against the above strains of microbes.