Ingenol mebutate is a tetracyclic diterpenoid ester obtained by formal condensation of the carboxy group of (2Z)-2-methylbut-2-enoic (angelic) acid with the 3-hydroxy group of ingenol. Used for the topical treatment of actinic keratosis. It has a role as an antineoplastic agent. It is a carboxylic ester, a cyclic terpene ketone and a tetracyclic diterpenoid. It is functionally related to an angelic acid and an ingenol. Ingenol derivatives inhibit proliferation and induce apoptosis in breast cancer cell lines, formulating novel derivatives from Ingenol esters may be an innovative approach to develop new lead compounds to reactivate latent HIV. Ingenol mebutate is an effective treatment for actinic keratosis.