Pentacyclic triterpene 5-phenylpenta-2,4-dienoyl esters from Peltastes peltatus (Vell.) Woodson.

Two new pentacyclic triterpene esters, peltastine A [3beta-[5-phenyl-(2E,4E)-penta-2,4-dienoyloxy]-urs-12-ene] and peltastine B [3beta-[5-phenyl-(2E,4E)-penta-2,4-dienoyloxy]-lup-20(29)-ene], have been isolated from the stem of Peltastes peltatus (Vell.) Woodson along with the previously reported beta-amyrin juarezate [3-[5-phenyl-(2E,4E)-penta-2,4-dienoyloxy]-olean-12-ene]. The structures of these compounds were established by MS, 1D- and 2D-NMR experiments as well as by chemical degradation.