Synthesis of some new isoxazole compounds and their biological tyrosinase and antioxidant activities

In this study, 7 new isoxazole compounds (8–14) were synthesized from the cyclization of chalcone compounds (1–7) containing different functional groups with hydroxylamine hydrochloride in alkaline medium. Tyrosinase and antioxidant properties of 8–14 were investigated. IC(50) values for the tyrosinase enzyme inhibition of compounds 8, 11, 12, and 13 were varied between 61.47 ± 3.46 and 188.52 ± 5.85, while compounds 9, 10 and 14 did not show any inhibition effect. The antioxidant properties of 8–14 were investigated by DPPH and CUPRAC methods. Compound 12 showed the best DPPH radical scavenging activity (SC(50): 40.21 ± 2.71), while 12 and 13 had shown the greatest Cupric ion reducing effect as 1.233 ± 0.015 and 1.245 ± 0.019 mg TEAC/mg, respectively. As a result, the change of functional groups in the synthesized compounds caused a significant difference in the biological properties of 8–14.