Isoprenoid compounds from Euphorbia portlandica. X-ray structure of lupeportlandol, a new lupane triterpene

phytochemical survey of the me2co extracts of the whole dried plant euphorbia portlandica led to the isolation of a new pentacyclic triterpene alcohol, with the lupane skeleton, named lupeportlandol. its structure was established as 3a-hydroxy-19ah-lup-20(29)-ene. the known pentacyclic triterpene glutinol and the steroid b-sitostenone were also isolated. the characterization of the new compound and its acetylated derivative was based on spectroscopic methods and an x-ray diffraction analysis. lupeportlandol acetate was inactive in cytotoxicity assays in vitro against three human tumor cell lines: mcf-7 (breast cancer), nci-h460 (non-small cell lung cancer) and sf-268 (cns cancer).