Synthesis, Electrochemical and Antibacterial Studies of hexa-aza-macrocyclic Complexes of Ni(II) and Cu(II) Ions

Abstract

Due to their distinct structural, electrical, and electrochemical properties, macrocyclic complexes have been recognized as potential models in a variety of areas, including electrocatalysis, biology, and medicine. In this study, two hexa-aza-macrocyclic complexes of Ni(II) and Cu(II) transition metals (denoted as [NiL] and [CuL]) were synthesized via template procedure. Based on the results of multiple spectroscopic characterization, a distorted octahedral geometry was proposed for both the complexes. The electrochemical results showed that the macrocyclic framework can stabilize the unusual oxidation states of Ni(II) and Cu(II) transition metal ions, as evidenced by the corresponding quasi-reversible Ni(II)/(III) and Cu(II)/(III) redox couples. Additionally, both the complexes were found to be promising antibacterial agents against the B. subtilis, S. aureus, P. aeruginosa, and E. coli pathogens. The Cu(II) complex had the largest inhibition zone (22[Formula: see text]mm) against B. subtilis, while the Ni(II) complex had the smallest (15[Formula: see text]mm).