Synthesis and Preliminary Anti-tumor Activity Evaluation of Ursolic Acid-resveratrol Conjugates

OBJECTIVE To design and synthesize ursolic acid-resveratrol conjugates and investigate their anti-cancer activities. METHODS Ursolic acid-resveratrol conjugates were synthesized from ursolic acid by esterification reaction, and the in vitro antitumor activity of target conjugates was assessed by MTT assay. RESULTS Twelve ursolic acid-resveratrol conjugates were synthesized, and structures were characterized by ¹H-NMR and MS analysis. The preliminary biological results showed that these conjugates displayed inhibitory activity on both MCF-7 and MDA-MB-231. Specifically, the inhibitory activity of conjugate 13b-c and 15b-c on MCF-7 was stronger than that of ursolic acid, resveratrol and the positive drug of tamoxifen. Additionally, all conjugates were nontoxic to normal MCF-10A cells. CONCLUSION The introduction of resveratrol unit into the structure of ursolic acid can enhance its anti-tumor activity.