Abstract: Seven novel amino acid derivatives of benzisoselenazolone were found to have significant glutathione peroxidase(GSH-Px)like activity as determined by coupling test using NADPH/GSSG reductase as an indicator. They catalysed the reduction reaction of hydroperoxides in the presence of GSH with good structure activity relationships. The activities of the compounds 1, 6 and 7 were almost equal to that of Ebselen, which is known as the best mimic of GSH-Px. It was also found that the concentration of the mimics and GSH, the temperature and the pH value of the reaction system had great effects on the catalytic activity of the mimics. The apparent activation energy of compounds 4 and 7 had been determined as 101 and 87.3 kJ/mol respectively.

Key words: benzisoselenazolone, amino acid derivative, Ebselen, glutathione peroxidase