A compound of Formula ll:or a pharmaceutically acceptable salt thereof wherein:L is ¨(CH2)m-；R4 is H or alkyl；L1 is ¨CH(R5)¨ or ¨C(=O)¨；L2 is ¨O¨ or ¨NH¨；R6 is H, or ¨(CH2)n C(=O)R8；R7 is H, alkyl, or ¨(CH2)p C(=O)OH；R8 is ¨OH, ¨CH3, ¨CH2C(=O)OH, or ¨(CH2)w¨CH(NH2)¨C(=O)OH；R9 is H, alkyl, or ¨C(=O)alkyl；m is 1, 2, 3, or 4； andn, p, and w are each independently 0, 1, 2, 3, or 4,wherein alkyl means a linear, branched, saturated or unsaturated carbon chainhaving 1 to 20carbon atoms. Compounds according to the invention have anti-oxidantproperties and areuseful in treating diseases or injuries associated with oxidative stress.(see above formula)
