Synthesis and in vitro antitumor activities of lupeol dicarboxylic acid monoester derivatives

Ten lupeol dicarboxylic acid monoester derivatives as new potent antitumor agents were synthesized and evaluated for in vitro antitumor activities against A549, LAC, HepG2 and HeLa cell lines. Among them, compounds 1–5 showed excellent antitumor activities against all tested tumor cell lines and compounds 6–10 exhibited high activities against A549, HepG2 and HeLa cells, exceeded lupeol, lupanol and doxorubicin. Compound 2 displayed the highest potent antitumor activities with IC₅₀ values of 5.78 μM against A549 cell, 2.38 μM against LAC cell, 6.14 μM against HepG2 cell and 0.00842 μM against HeLa cell.