Ring Open to Mono Ester of Norcantharidin Derivatives Also Can Inhibit Hep G2 Cell Line?

Starting from maleic anhydride, followed by the cyclo-addition, bromination and alcoholysis with different alcohols, the corresponding monoacid esters were successfully synthesized in medium to high yields. The structures were identified by H-1 NMR, C-13 NMR and IR spectroscopy. And the anti-tumor activity human hepatoma cell line Hep G2 was evaluated in vitro by MTT assay. The preliminary experimental results showed that 5, 6-dibromo norcantharidin mono metylester (C1) has a strong anti-hepatoma activity in Hep G2 cell line in vitro, indicating that ring open to mono ester of norcantharidin derivatives can also inhibit Hep G2 cell lines.