A novel 19-nor-neo-clerodane derivative, teucorymbin, and three known
neo-clerodanea (19-acetylgnaphalin, teucjaponin A and 6-acetylteucjapo
nin B) were isolated from the aerial parts of Teucrium corymbosum. The
structure of teucorymbin 19-nor-neo-cleroda-4,13(16),14-trien-20,12S-
olide] was established by chemical and spectroscopic means.