ent-Verticillane-type diterpenoids from the Japanese liverwort Jackiella javanica

Three ent-verticillane diterpenoids (1-3) have been isolated from the Japanese liverwort Jackiella javanica, together with five known ent-verticillane, three known ent-kaurane diterpenoids, and five sesquitepenoids. Their structures are established by application of extensive NMR spectroscopic analysis, chemical conversions and X-ray crystallographic studies.