抄録
Three Epstein-Barr virus activating principles have been isolated from the leaves of Sapium sebiferum (Euphorbiaceae), which is one of commonroadside and garden trees in Japan. By chemical and spectroscopic evidence they were identified as tigliane type diterpeneesters with the structures of 1, 2 and 3. 1 and 2 strongly induced an early antigen of the virus in a Raji cell, while 3 did so weakly. The activity of some derivatives of 2 are also discussed.
