Brian Johnson, Chemistry
Multicopper oxidases (MCO’s) possess an unusual trinuclear copper that catalyzes the reduction of oxygen to water. However, the mechanism of oxygen reduction is unclear. To elucidate the mechanism of oxygen reduction, this study focuses on the synthesis and characterization of a model of the copper active site. Research in biomimetic chemistry seeks to design models that replicate the structure of enzymes in a much smaller molecule. This model, because it is smaller, is easier to characterize, so intense study in models lend evidence toward the behavior of their respective enzymes. The model in this research study uses a novel copper (I) complex with a new ligand based on the tris-(2-pyridylmethyl)amine (TPMA) ligand family where nitrogen-based donors are employed to replicate the histidine bases in these MCO’s. This ligand is synthesized from a 1,3,5-triethylbenzene derivative so the ethyl groups force the nitrogen ligand branches to adopt a conformation that brings the nitrogenous bases in close proximity, mimicking enzymatic structure. NMR analysis showed production of the desired ligand, but the ligand has proven difficult to purify from its mono- and bis- functionalized derivatives. Future research will focus on isolating the ligand and improving yield of the synthesis. Once pure ligand is obtained, addition of copper and crystallization of the resulting complex to precisely determine its structure will follow.
Gavin, Joshua, "Sythesis and Characterization of a Model Multicopper Oxidase" (2019). Celebrating Scholarship and Creativity Day. 81.