Synthesis of Norcantharidin Complex Salts

A new series of norcantharidin salt derivatives was designed and synthesized in good yield. The compounds structures were characterized by H-1-NMR, C-13-NMR, and IR spectra. These norcantharidin salts 5 exhibit good antitumor activity against both liver cancer and colon cancer cell lines in vitro, which seems to direct a right trend for the modification on cantharidin structure.