title: Mechanism of the Reduction of an Oxidized Glutathione Peroxidase Mimic with Thiols.
abstract: N,N-dimethylbenzylamine-2-selenol is a well-known, efficient glutathione peroxidase mimic. This compound reduces peroxides through a three-step catalytic mechanism, of which the first step has been well-characterized computationally. The mechanism for the reaction of N,N-dimethylbenzylamine-2-selenenic acid with a thiol, the second step in the catalytic cycle, is studied using reliable electronic structure techniques. Two different mechanisms are identified, using either a thiol or a deprotonated thiolate as the nucleophile. It is found that the lowest energy barrier mechanism incorporates two explicit solvent molecules to shuttle the thiol hydrogen to the leaving hydroxyl group, while the alternative mechanism using the thiolate has a barrier four times higher.
authors.affiliation: Department of Chemistry, Dalhousie University , Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Gavin S
authors.initials: GS
authors.lastname: Heverly-Coulson
authors.affiliation: Department of Chemistry, Dalhousie University , Halifax, Nova Scotia, Canada B3H 4R2.
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Boyd