Four new sesquiterpene derivatives from Dendrobium findlayanum

Three new sesquiterpene glycosides with alloaromadendrane and ylangene-derived type aglycones, named dendrofindlayanosides A-C ( 1-3 ), one new cyclopacamphane type sesquiterpene named dendrofindlayanobilin A ( 4 ), together with five known compounds have been isolated from stems of Dendrobium findlayanum. Their structures were determined on the basis of spectroscopic and chemical methods.