A new ent-norabietant diterpenoid from roots of Euphorbia lathyris L.

Abstract A new highly oxidized ent -norabietane diterpenoid named lathyrisol A ( 1 ) was isolated from roots of Euphorbia lathyris L. The structure and absolute configuration of 1 were elucidated on the basis of data obtained by HRESIMS, NMR, and the Cu-Kα radiation X-ray diffraction analysis. This compound is the first example of naturally occurring norabietane diterpenoid with an exocyclic olefin at the C-4 position.