Chemical Modification of Natural Medicines by Amino Acids and Oligopeptides

Amino acids and peptids are the basic substance in life activities, and have special physiological functions. Recently, there have been more and more researches on the structural modification of natural medicines by amino acids or oligopeptides. In this paper, the natural medicines modified with amino acids or oligopeptides and their pharmacological activities were summarized. Topics covered included the natural medicines with poor solubility and high side effects, such as betulinic acid, 3-oxo-oleanolic acid, camptothecine, vincristine, glycyrrhizic acid, glycyrrhetinic acid, and so on.