Pyridine and pyrimidine analogs of acetaminophen as inhibitors of lipid peroxidation and cyclooxygenase and lipoxygenase catalysis.

ABSTRACT: Herein we report an investigation of the efficacy of pyridine and pyrimidine analogs of acetaminophen (ApAP) as peroxyl radical-trapping antioxidants and inhibitors of enzyme-catalyzed lipid peroxidation by cyclooxygenases (COX) and lipoxygenases (LOX). In inhibited autoxidations we find that ApAP, the common analgesic and antipyretic agent, is a very good antioxidant with a rate constant for reaction with peroxyl radicals (k(inh) = 5 x 10(5) M(-1) s(-1)) that is higher than many widely-used phenolic antioxidants, such as the ubiquitous butylated hydroxytoluene (BHT). This reactivity is reduced substantially upon incorporation of nitrogen into the phenolic ring, owing to an increase in the O-H bond dissociation enthalpy of pyridinols and pyrimidinols with respect to phenols. Incorporation

SUBMITTER: Nam TG 

PROVIDER: S-EPMC2873786 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature