Synthesis, characterization, antioxidant and tyrosinase inhibitory activities of hesperetin derivatives

A series of hesperetin derivatives were synthesized by Williamson etherification, Steglich esterification and ring-opening by modifying the 7 hydroxyl group, 3' hydroxyl group and C ring of hesperetin. All compounds were confirmed by IR, 1H NMR, 13C NMR and HR-MS. The antioxidant activity of hesperetin derivatives was tested by ABTS method. Hp-1, Hp-2(b,d), Hp-3, Hp-5, Hp-6(a-d) and Hp-7(a-c) had antioxidant effects, and Hp-7a had the strongest antioxidant effect, which was better than the positive control quercetin, and the TEAC value was 4.62 mM. Hp-2b, Hp-3, Hp-7b and Hp-7c hesperetin derivatives had inhibitory effects on tyrosinase, and were superior to α-arbutin positive control. Hp-2b had the best inhibitory effect on tyrosinase, and the IC50 value was 0.657 ± 0.093 mmol·L−1.