Synthesis and antitumor, antityrosinase, and antioxidant activities of xanthone.

Ten substituted 1,3-dihydroxyxanthones were synthesized in one step. The yields ranged from 40 to 76%. Compounds 8-10 were first reported. Next, the compounds' in vitro anti-proliferative activities against nine human cancer cell lines, antityrosinase, and antioxidant activities were evaluated. Compounds 1, 4, 6-7, and 9-10 exhibited enhanced cytotoxicity against certain cancer cells. Compounds 2, 8, 9, and 10 inhibited tyrosinase activity to a certain extent. In addition, compound 4 exhibited the best antioxidant activity, which was consistent with theoretical calculations. These results demonstrated that compounds 1-2, 4, and 6-10 were promising leads for further investigation.