Prodrugs of triterpenoids and their derivatives.

Triterpenoids are structurally diverse organic compounds that exist widely as natural products. Triterpenoids and their derivatives possess a wide range of biological effects including hepatoprotective, hypoglycemic, immunomodulatory, anti-inflammatory, anti-oxidant, and antitumor activities. In particular, the lupane-, oleanane-, and ursane-type triterpenes have been reported to exhibit pharmacological effects without prominent toxicity even at higher concentrations. Whereas, the poor drug-like properties (e.g., low solubility and selectivity, poor bioavailability, and short half-life) severely limit their applications. This review summarized the advances in prodrug strategies for improving the drug-like properties of different types of triterpenoids, and the information indicated in the review will surely stimulate further efforts toward the development of these compounds for potential clinical uses.