Aim To design and synthesize norcantharidin disodium phosphate derivatives. Methotis Diels-Alder reaction between furan and maleic anhydride afforded dehydronorcantharidin, and subsequent hydrogenation, phosphorylation, and basification gave compounds 1 and 2, separately. Resuits The structures of compounds were confirmed by IR, NMR and FAB-MS. The aqueous solubility of 1 and 2 were improved, compared with the parent compounds, and their activities were more potent than norcantharidin 4 against MGCS03 cell lines. Conclusion The phosphorylation of norcantharidin analogues is an effective way to increase the activity and solubility.
