The aim of this review is to update current knownledge on the betulinic, ursolic and echinocystic acids and their natural and semisynthetic analogs, focussing on their cytotoxic and anti-HIV activities. Then, the last results of the authors team on unusual semisynthetic derivatives of these triterpenoids will be presented in order to establish structure / activity relationships.
Keywords: betulinic, ursolic, echinocystic acid, antitumor, anti-hiv agents, anti-hiv activities