1989 Volume 37 Issue 2 Pages 354-357
By reinvestigation of the aerial parts of Ajuga nipponensis, four new bitter neo-clerodanes, ajugamarins C1, B2, B3 and D1, and a known diterpene, ajugarin-I, have been isolated. The structures of these diterpenes were elucidated on the basis of spectral data and chemical correlations.