Synthesizing hybrid molecules is one the best manner to achieve novel promising agents. Consequently, series of new thiazoles having coumarin nucleus were synthesized from 3-acetylcoumarin thiosemicarbazones. Cyclization of thiosemicarbazone derivatives with ethyl 2-chloroacetate, 1-chloropropan-2-one and 2-bromo-1-phenylethanone afforded the corresponding 4-thiazolidinones, 4-methylthiazoles and 4-phenylthiazoles, respectively. The expected antimicrobial propriety for the synthesized thiosemicarbazone and thiazole derivatives were investigated. The thiosemicarbazones and thiazolidin-4-ones showed moderate activities against G +ve and G -ve bacteria.