11β,13-dihydrozaluzanin C acetate;[(3S,6aR,8S,9aR,9bS)-3-methyl-6,9-dimethylidene-2-oxo-3a,4,5,6a,7,8,9a,9b-octahydro-3H-azuleno[4,5-b]furan-8-yl] acetate
Abstract The investigation of two Brachylaena species afforded in addition to known sesquiterpenelactones and other constituents five new lactones, a germacranolide, a guaianolide and three eudesmanolides. The structures were elucidated by spectroscopic methods. The chemotaxonomy of this complex genus is discussed.