The study deals with synthesizing new thiadiazole compound (2-(5-amino-1,3,4-thiadiaz0l-2-yl)-4,6-dinitrophenol)(1) by reaction of 3,5-dinitrosalicylic acid with thiosemicarbazide in Phosphoric chloride, then it is (1) reacted with 2-Bromobenzaldehydeto getting Schiff base (2-(5-((2-bromobenzylidene) amino)-1,3,4-thiadiaz0l-2-yl)-4,6-dinitrophenol)(2). T0he compound (2) will reacted with (chloroacetylchloride, thioglycolic acid, glycine, sodium azide, phthalic anhydride) to give (β-lactam, thiazolidine, imidazolidine, tetrazole, oxazepine) derivatives respectively. The new synthesized compounds have been identified by their melting points, 1H-NMR, 13C-NMR and FT-IR spectra. Then the biological activity studied for all the synthesized derivatives toward two type of bacteria.