Dihydroxysesquiterpenoids from Santalum insulare of French Polynesia

Two new dihydroxysesquiterpene derivatives, elvirenol (1) and elvirol (2), along with five known compounds, (Z)-2β-hydroxy-14-hydro-β-santalol (3), (Z)-2α-hydroxyalbumol (4), (Z)-campherene-2β,13-diol (5), bisabola-2,10-dien-7,13-diol (6) and 2R-(Z)-campherene-2,13-diol (7) were isolated from the n-hexane extract of Santalum insulare (Santalaceae) from French Polynesia. Elvirol and elvirenol have a new sesquiterpene skeleton named elvirane. The structures were determined by extensive NMR studies. Compounds with antibacterial and antifungal activities identified in S. album heartwood were also present in S. insulare and may contribute to the recognized activities of this material in Polynesian traditional medicine.