Catechol oxidase activity of comparable dimanganese and dicopper complexes

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 47; no. 43; pp. 15555 - 15564
• Main Authors: Magherusan, Adriana M, Nelis, Daniel N, Twamley, Brendan, McDonald, Aidan R
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 21.11.2018
• Subjects: Acetonitrile; Biomimetic Materials - chemical synthesis; Biomimetic Materials - chemistry; Catechol; Catechol Oxidase - metabolism; Catechols - chemistry; Coordination Complexes - chemical synthesis; Coordination Complexes - chemistry; Copper; Copper - chemistry; Crystallography; Ligands; Manganese; Manganese - chemistry; Models, Molecular; Molecular Conformation; Oxidase; Oxidation; Oxidation-Reduction; Substrates; Transition metals
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c8dt01378k

Synthetic Cu complexes have been widely investigated as model systems for catechol oxidase enzymes. The catechol oxidase reactivity of Mn complexes has been less explored, and the effect of metal substitution in catecholase mimics has not been explored. A series of Mn and Cu complexes supported by the same poly-benzimidazole ligand framework have been synthesised and investigated in catecholase activity in acetonitrile medium using 3,5-di-tert-butylcatechol (3,5-DTBC) as a substrate. The Cu complexes proved to be good catechol oxidase mimics with moderate k values (∼45 h ). The kinetic parameters for Mn complexes exhibited lower k values (∼8-40 h ) when compared to the Cu complexes. Our findings demonstrate that later transition metals supported by relatively electron rich ligands yield the highest k values for catechol oxidation.