Antimicrobial Properties of Cu(I) and Cu(II) Complexes of a Schiff Base Ligand

A Schiff base ligand was synthesized from m-phenylenediamine and 2-hydroxybenzaldehyde in a molar ratio of 1:2 and the (Cu+& Cu2+) complexes were synthesized from the ligand by refluxing the mixture at 60 oC for 2 hours. Characterization of the synthesized compounds was carried out using UV-Vis, FT-IR, NMR and mass spectrometry. The electronic spectral band and magnetic moment of the Cu+ and Cu2+complexes are 402 nm, 0.9 BM and 356 nm, 1.13 BM respectively and assigned 2B1g → 2A1g transition, while the FT-IR spectral of the ligand when compared with that of the complexes shifted in the azomethine and phenolic-OH band of by about 14.29 to 62. 18 cm-1.Spectra of the complexes indicate that coordination of ligand and metal occurred through the carbonyl Oxygen and the azomethine Nitrogen which agrees with slight difference between the chemical shift value of the ligand and its complexes in the carbon-13 NMR data. The electronic data for the complexes were consistent with a distorted octahedral geometry. The synthesized ligand and its Cu+ and Cu2+ complexes were screened against gram positive, gram negative bacterial and some fungi. The result indicates that the ligand and its copper (I) and (II) complexes had high activity against Methicillin Resistant Staph aureus and Staphylococus Aureus with MIC of 6.25 µg/ml, zone of inhibition of 29, 30, 32 cm respectively which is almost equal and higher than the zone of inhibition of standard drugs with zone of inhibition of 32 and 29 cm at 10 µg/ml.