Five new kaurene-type diterpenoids, shikoccin (1), O-methylshikoccin (2), epoxyshikoccin (3), O-methylepoxyshikoccin (4) and shikoccidin (5) were isolated from Rabdosia shikokiana var. occidentalis. All these compounds except for 5 possess a hitherto unknown 8, 9-seco-ent-kaurene skeleton.
