Nine amino acid compounds (3～11) of benzoisoselenazolone were synthesized, where the phenyl ring at 2 position of 2-phenyl-1,2-benzoizoselenazol-3(2H)-one (Ebselen) with well-known antioxidative activity was replaced by ethyl aminoacetates. Effects of compounds 3～11 as well as Ebsene on Fe^2^+ / cysteine and vitamin C-induced rat liver microsome lipid peroxiation were investigated. Compounds 5,6 were more active than Ebselen in Fe^2^+ / cysteine system (Their IC~5~0 were 14,12 and 24μmol/L respectively ). And in vitamin C system, compound 4,7,8,9 and 10 were more active than Ebselen (Their IC~5~0 were 33,51,39,28,17.5 and 66μmol/L respectively) .

Key words: AMINO ACID, PEROXIDATION, LIPID(E)