Free radical scavenging activity of newly designed sesamol derivatives

Chemical compounds with antioxidant behavior are recognized as efficient protectors against the harmful effects of reactive oxygen species (ROS) and other chemicals overproduced due to oxidative stress (O.S.). Sesamol has been shown to offer significant benefits in the treatment of many OS-induced diseases. The present work focuses on the free radical scavenging activity of some sesamol derivatives, recently proposed as promising antioxidants. This activity was studied, taking into account three reaction mechanisms: formal hydrogen atom transfer (f-HAT), single electron transfer (SET), and radical adduct formation (RAF). The investigation was based on thermochemistry and kinetics, using solvent models to mimic aqueous and lipid environments. The influence of pH on the investigated activity was also considered. The studied sesamol derivatives were found to be potent peroxyl radical scavengers, which suggests that they have potential use to mitigate O.S. and related diseases. SET and f-HAT were identified as the main reaction mechanisms, while RAF was ruled out as a significant chemical route. It is expected that the results from this work will promote further investigations on the possible health benefits of the newly designed sesamol derivatives studied here. Recently proposed derivatives of sesamol as better oxidants than the parent molecule are predicted to react faster, with several orders larger rate constants than sesamol itself.