Abstract

Synthesis and spectroscopic characterization of transition metal complexes of a 14-membered tetraaza [N4] macrocyclic ligand and their biological activity

Author(s): S.G.Shankarwar, B.B.Nagolkar, V.A.Shelke, T.K.Chondhekar

Macrocyclic ligand was derived from â-Diketone 1-(3-chlorophenyl)-3-(2- hydroxyphenyl) propane-1,3-dione, o-phenylene diamine and itsmetal complexes with Cr(II),Mn(II), Co(II), Ni(II), and Cu(II), have been synthesised with newly synthesised biologically active macrocyclic ligand and characterized by spectral and other physicochemical techniques such as elemental analysis, molar conductivity, magnetic susceptibility, thermal analysis, Xray diffraction, IR, 1H-NMR, UV-Vis spectroscopy and mass spectrometry. The synthesized complexes are stable powders insoluble in common organic solvents such as ethanol, benzene chloroform, carbon tetrachloride. From the analytical data, stiochiometry of the complexes was found to be 1:2 (metal: ligand). Thermal behavior (TG/DTA) and kinetic parameters calculated by Horowitz-Metzer and Coats-Redfernmethod suggestmore ordered activated state in complex formation.All the complexes are of high spin type and six coordinated. On the basis of IR, electronic spectral studies and magnetic behavior, an octahedral geometry has been assigned to these complexes. The antibacterial and antifungal activities of the ligand and its metal complexes, as growth inhibiting agents, has been screened in vitro against Staphylococcus aureus, Escherichia coli andAspergillus Niger, C.Albicans respectively.