Hydroxyalkyloxy substituted tetraphenylporphyrins: Mechanism and superoxide scavenging activity

Abstract

The novel electrochemical approach based on coulometric response of electro-generated superoxide (O[Formula: see text] was used to determine scavenging properties of 2H-5,10,15,20-tetrakis (4-hydroxyphenyl)porphyrin (H[Formula: see text]T(4-OHPh)P); 2H-5,10,15,20-tetrakis[4-(2-hydroxyethyloxy)phenyl]porphyrin (H[Formula: see text]T(4-OH(CH[Formula: see text]OPh)P); 2H-5,10,15,20-tetrakis[4-(4-hydroxybutyloxy)phenyl]porphyrin (H[Formula: see text]T(4-OH(CH[Formula: see text]OPh)P); Zn-5,10,15,20-tetrakis[4-(4-hydroxyethyloxy)phenyl]porphyrin (ZnT(4-OH(CH[Formula: see text]OPh)P) superoxide. It has been identified that the porphyrins under study possess good antioxidant properties. The analysis of possible interactions between porphyrins and superoxide anion-radical has shown that high values of superoxide scavenging activity of tetraphenylporphyrins with alcohol chains can be explained by the nucleophilic attack of O[Formula: see text] on the C–C bonds of alcohol.