A series of six mono nuclear Schiff-base complexes, namely [Cu(L1)(NO3)]NO3 (1), [Cu(L2)(NO3)]NO3 (2),[Cu(L1)phen](NO3)2(3),[Cu(L1)bpy](NO3)2 (4),[Cu(L1)pybiH](NO3)2(5) and [Cu(L1)dpk](NO3)2(6) where L1 and L2 is a tridentate (N,N,N) Schiff-base ligand L1 = (N,N-dimethyl-N`-[phenyl(pyridin-2-yl)methylene]ethane-1,2-diamine), L2 = (N-[phenyl(pyridine-2-yl)methylene) (pyridin-2-yl]methanamine), phen = 1, 10-phenanthroline, bpy = 2, 2'-bipyridinyl, pybim = 2-pyridin-2-yl-1H-benzoimidazole and dpk = di-pyridin-2-yl-methanone were synthesized and characterized by elemental analysis,UV-Vis, IR and EPR spectroscopy.In the complexes 3, 4, 5 and6the metal ion is coordinated by three nitrogen atoms from L1 or L2ligand and two nitrogen atoms from the bidentate auxiliary ligand and approximately square pyramidal coordinate geometry.Complexes1 and 2, the metal ion is coordinated by three nitrogen atoms from the Schiff base ligand and two oxygen atoms from nitrate anion.The in-vitro antimicrobial activity of the complexes were tested against the bacteria Escherichia coli, Staphylococcus aureus, Bacillus subtilis, fungi Candida albicans and Aspergillusflavus by disc diffusion method. All the copper (II) complexes show moderate antimicrobial activity.
