Weakly antiferromagnetic vanillin and acetate bridged dinuclear Ni() compound exhibiting catecholase-like activity and biological properties

A dinuclear nickel compound that features vanillin (van) and acetate (OAc) bridging ligands, [Ni 2 (μ-van) 2 (μ-OAc)(NCS) 3 (H 2 O)]·5H 2 O 1 , was synthesized and characterized using various techniques. Crystal structure analysis revealed a pair of Ni( ii ) ions bridged by an acetate anion through a μ 2 -η 1 :η 1 coordination mode. At the same time, vanillin bridges both nickel( ii ) centers through phenolic oxygen, separating the two Ni ions by a distance of 3.001(7) Å. The temperature-dependent magnetism indicates weak antiferromagnetic behaviour in compound 1 , following the Curie-Weiss law with Curie constant C = 1.0145 cm 3 K mol −1 and Weiss constant = −4.1 K. Compound 1 was evaluated for its ability to mimic the catechol oxidase enzyme using 3,5-di- tert -butylcatechol as a model substrate with a K cat value of 157.1 × 10 2 h −1 . Furthermore, compound 1 was tested for its cytotoxicity against HepG2 cancer cells and DNA cleavage properties. A dinuclear Ni( ii ) compound, [Ni 2 (μ-van) 2 (μ-OAc)(NCS) 3 (H 2 O)]·5H 2 O 1 with p -vanillin and acetato bridging ligands have been structurally characterized and tested for catecholase-like and biological activities.