Synthesis, Characterization, Electrochemical and Antimicrobial Studies of N4-Macrocycles of Cobalt(II) and Nickel(II) Metal Ions

The precise analysis of redox chemistry of MN4-based macrocyclic complexes is of great importance because of stabilization of unusual oxidation states of metal ions by macrocyclic ligand and thus have various applications in biochemistry, electrochemistry, electrocatalysis, pharmaceuticals etc. In this work, MN4-macrocyclic complexes of Co (II) and Ni(II) transition metal ions have been synthesized by using template condensation method. Further, the MN4-macrocyclic complexes were characterized by elemental, molar conductance and multiple spectroscopic analysis. The spectral and elemental analysis suggested that both complexes would possess the saddle shape distorted octahedral geometry. Further, the electrochemical investigation of both complexes was carried out by cyclic voltammetry. Both complexes showed quasi-reversible one-electron transfer redox process indicating the stabilization of oxidation state of central metal ions. Moreover, the MN4-macrocyclic complexes have shown to have good antimicrobial activity against the various pathogens such as Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Bacillus subtilis (B. subtilis) and Staphylococcus aureus (S. aureus).