In this research new derivatives of imidazoles were prepared using multicomponent reactions of primary amines, isocyanates, diethyl oxalate and guanidine in water at room temperature in the presence of baker’s yeast as catalyst in good yields. The short time of reaction, high yields of product and easy separation of them are some advantages of this procedure. Another work in this research is investigation of antioxidant property of some synthesized compounds by diphenyl-picrylhydrazine (DPPH) radical trapping experiment. Presently, bacteria that are not destroyed with drug have generated many problems in the performance of much transferable disease. For this reason, discovering appropriate and new procedures for the dealing with these pathogens are important and recent study has focused on the investigation of the antibacterial effects on the prepared compounds. Manuscript profile