Highly oxygenated sesquiterpenes from the liverwort Trocholejeunea sandvicensis

Four pinguisane type sesquiterpenes were isolated from the liverwort Trocholejeunea scandvicensis, together with three aromatic compounds. The structures of the cited compounds were established on the basis of spectroscopic means. The first two compounds were new sesquiterpenes, while the other compounds were previously isolated from other liverworts and lichen sp., respectively. The stereochemistry for lejeuneapinguisanolide was determined by X-ray analysis, a possible biosynthetic pathway to it was postulated. The other new sesquiterpene is lejeuneapinguisenone.