Synthesis of Quercetin-Acid Esters and Its Reduction of H₂ O₂ -Triggered PC12 Cells Damage by Down-Regulating ROS

Quercetin is a kind of polyphenolic flavonoid compounds which has perfect antioxidant properties. However, quercetin is not available in many situations due to its poor bioavailability. In this work, the QAEs with better solubility and even stronger antioxidant properties were synthesized, through the esterification between quercetin and the chlorinated cinnamic acid or its derivatives, whose chlorination were achieved by using SOCl₂ . The protective effects of the QAEs were evaluated by the H₂ O₂ -induced apoptosis experiment in rat adrenal pheochromocytoma cells (PC12 cells) and its ability to remove ROS generated by oxidative stress. Compared with the original quercetin group, the QAEs groups showed much improved cell viability and capability of removing ROS, which means their higher bioavailability than the parent.