Norcantharidin analogues: a patent review (2006 - 2010).

Norcantharidin (7-oxabicyclo [2.2.1] heptane-2,3-dicarboxylic anhydride) is the demethylated form of cantharidin. Norcantharidin not only has strong anticancer activity, but also eliminates most side-effects in the urinary system, does not cause myelosuppression and increases the number of white blood cells. With structural modification, norcantharidin analogues show potential anticancer activities. A comprehensive patent review of norcantharidin analogues from 2006 to 2010 is presented. Protein phosphatase 1, 2A, 2B and 5 inhibitors are described. The review summarizes the new compounds and lays the foundation for seeking more effective anticancer compounds. Although norcantharidin has improved activity and toxicity, the effects routinely do not satisfy the current clinical need. Exploring better analogues is vital for changing the current situation, but norcantharidin is a good lead compound.