Effect of chelation on therapeutic potential of drugs : Synthesis and characterization of novel VO~(II), Fe~(II), Cu~(II) and Zn~(II) complexes of ornidazole drug and evaluation of their antibacterial activity

摘要

Complexes of VO~(II), Fe~(II), Cu~(II) and Zn~(II) transition metal ions with an antibacterial and antiprotozoal drug ornidazole (ONZ) [1-chloro-3-(2-methyl-5-nitroimidazole-1-yl)propane-2-ol] were synthesized and characterized by elemental analysis, IR, UV-Vis, magnetic moment, molar conductance, ~1H NMR, thermal and FAB-mass spectra. Analytical data revealed that all the complexes exhibited 1 : 2 (metal : ligand) ratio with coordination number 4, 5 or 6. IR spectra show that ligand (ONZ) is coordinated to the metal ions in a monodentate manner through N donor site of imidazole ring. The thermal behavior of [Cu(ONZ)2(H2O)2O2].2H2O complex show that the hydrated complexes lose water molecules first, followed by decomposition of ligand molecule in the subsequent steps. Ornidazole (ONZ) drug ligand and its metal complexes were also screened for in vitro antibacterial activity against Escherichia coli, Staphylococcus aureus and Proteus mirabilis. Effect of metal ions chelation on antibacterial potential of ornidazole (ONZ) drug has been studied.