中文摘要：

白桦酸是天然的羽扇豆烷型三萜类化合物，具有较强的抗HIV活性，且作用机制独特。多年来，为进一步改善白桦酸的理化性质、药动学、生物利用度及抗HIV活性，人们通过对其结构的修饰改造，获得了一系列具抗HIV活性及不同作用机制的白桦酸衍生物。综述通过对白桦酸结构中不同位点的修饰改造所得衍生物的抗HIV活性、作用机制及构效关系。

英文摘要：

Betulinic acid is a natural lupine-type triterpene, which possesses potent anti-HI~ activity and a unique mechanism of action. In recent years a series of betulinic acid derivatives with anti-HIV activities and different mechanisms of action have been obtained through structure modifications in order to improve the physico-cbemical properties, pharmacokinetics, bioavailability and anti-HIV activity of betulinic acid. The anti-HIV activities, mechanisms of action and structure-activity relationships of betulinic acid derivatives synthesized through structure modifications at various sites on betulinic acid were reviewed.