Novel di- and trisubstituted thiazole derivatives bearing heterocyclic, aromatic, chalcone, and carboxyalkyl-heterocyclic moieties were synthesized. Compounds possessing significant antibacterial activity, comparable to that of commercial antibacterial agent ampicillin, against Rhizobium radiobacter, Xanthomonas campestris, and Escherichia coli were identified. Some of the synthesized compounds exhibited a very high antioxidant activity.