Keeping in view the pharmacological potential of azetidinones, thiazolidinones and coumarins, the title compounds containing these nuclei were synthesized. The 4-methyl -7-hydroxy coumarin (1) on treatment with hydrazine hydrate affords 2-hydrazo- 4-methyl -7-hydroxy coumarin (2). The N- (2’-imino-4’-methyl-7’-hydroxy coummarinyl)-imino substituted benzene (3) was synthesized by reaction of compound 2 with various aromatic aldehydes. Condensation of compound 3 with chloroacetyl chloride in presence of 1,4-dioxan and triethyl amine yields the 3-chloro-4- (substituted)-1-(2’-imino-4’-methyl-7’-hydroxy coumarinyl) azetidin-2-one (4a-d). Further more condensation of 3 with thioglycollic acid in presence of 1,4-dioxan and anhydrous aluminium chloride gives 2-(substituted phenyl)-3-(2’-imino-4’-methyl-7’-hydroxy coumarinyl)-1,3-thiazolidinone (4’a-d). Elemental and spectral characterization established the identity of these compounds. All the products were screened in vitro for their anti microbial activity against different strains of urinary tract pathogens. All compounds exhibited significant antimicrobial activity compared to the standard drug nitrofurantoin. Key words: Azetidinones, thiazolidinone, coumarin, nitrofurantoin, E. coli, P. auregenosa, K. pneumoniae, P. mirabilis E. faecalis, and S.aureus. Dhaka Univ. J. Pharm. Sci. Vol.4(2) 2005 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website