Synthesis and antioxidant activities of N-thiophenyl ebselenamines: a 77Se{1H} NMR mechanistic study

Abstract

The step-by-step redox process of bis-[2-phenyl-1,2-benzisoselenazol-3(2H)-one-7-yl]diazene i.e. azo-bis-ebselen in the presence of PhSH and H₂O₂ was reported using ⁷⁷Se{¹H} NMR spectroscopy. The synthesis of N-thiophenyl ebselenamines as well as selenenyl sulphides is described. N-Thiophenyl ebselenamines quenched lipidperoxyl radicals much more efficiently than α-tocopherol and were highly regenerable by the presence of aqueous ascorbic acid in a two-phase (chlorobenzene/water) azo-initiated peroxidation system. All novel N-thiophenyl ebselenamines and their corresponding selenenyl sulphides were found to be very good glutathione peroxidase mimics compared to ebselen in the coupled reductase assay.