Compound 3-[{(3-(2’-Nitrophenyl)}-prop-2-enoyl]-4-hydroxy-6-methyl-2H-chromene-2-one (III) has been synthesized by the condensation of 3-acetyl-4-hydroxymethyl-coumarin with 2-benzaldehyde in presence of piperidine. Compound(III) was further reacted with transition metal salts to prepare metalchelates compd.(IVa to compd. IVe).The constitution of the product has been supported by elemental analysis, IR spectra and conductivity measurements. The products have been screened for their in vitro growth inhibitory activity against several microorganisms. In-vitro anti microbial activity of all synthesized compounds and standard drugs have been evaluated against four strains of bacterial culture and one fungus, which includes two gram +ve bacterial culture and two gram -ve bacterial culture, which show net enhancement in activity on co-ordination of metals with ligand but moderate activity as compare to standard drugs.