1042-1050A new series of 3-[4-(1H-benzo[d] imidazol-2-yl) oxazol-2-yl]-2-thiazolidin -4-ones 4 and 1-[4-(1H-benzo[d] imidazol-2-yl) oxazol-2-yl)-3-azetidin-2-ones 5 have been prepared from 2-acetyl benzimidazole 1. Compound 1 on treatment with urea in presence of I2 furnishes 4-(1H-benzo[d] imidazol-2-yl) oxazol-2-amine 2, which on condensation with aromatic aldehydes affords the corresponding Schiff bases 3. Cyclocondensation of 3 with thioglycollic acid produces the benzimidazolyl oxazolyl thiazolidin-4-ones 4, whereas, reaction of 3 with chloroacetyl chloride in presence of triethyl amine furnishes benzimidazolyl oxazolyl azetidin-2-ones 5. The structures of the newly synthesized compounds 3-5 have been elucidated on the basis of spectral (IR, 1H and 13C NMR and MS) and analytical data. The title compounds 4 and 5 have been screened for their antimicrobial activity. Some of the compounds exhibit promising antimicrobial activity