Antibacterial and catecholase activities of Co(III) and Ni(II) Schiff base complexes

X-ray structural analyses of two newly synthesized Schiff base-complexes, [Co(L)3] (1) and [Ni(L)2] (2) [HL = 2-((E)-(2-pyridine-2-pyridin-2-ylthio)ethylimino)methyl)phenol], reveal the bidentate chelation behavior of the ligand HL with octahedral and square planar geometries at the metal centers in 1 and 2, respectively. Both the compounds show antibacterial activity as well as catecholase activity. The antibacterial activities of the compounds were investigated on gram positive and gram negative bacteria; compound 2 was found to be better in terms of antibacterial activity than 1 against both the bacteria. Moreover, both compounds catalyse the oxidation of 3,5-ditertiarybutylcatechol in methanol in the presence of molecular oxygen with first order reaction kinetics and turn over numbers 3.48 × 103 h−1 (1) and 2.68 × 103 h−1 (2).

Graphical abstractX-ray structural analyses of two newly synthesized Schiff base-complexes, [Co(L)3] (1) and [Ni(L)2] (2) [HL = 2-((E)-(2-pyridine-2-pyridin-2-ylthio)ethylimino)methyl)phenol], reveal the bidentate chelation behavior of the ligand HL with octahedral and square planar geometries at the metal centers in 1 and 2, respectively. Both the compounds show antibacterial activity as well as catecholase activity. The antibacterial activities of the compounds were investigated on gram positive and gram negative bacteria; compound 2 was found to be better in terms of antibacterial activity than 1 against both the bacteria. Moreover, both compounds catalyse the oxidation of 3,5-ditertiarybutylcatechol in methanol in the presence of molecular oxygen with first order reaction kinetics and turn over numbers 3.48 × 103 h−1 (1) and 2.68 × 103 h−1 (2).Figure optionsDownload full-size imageDownload as PowerPoint slide