Two new abietane diterpenoids from the caulis and leaves of Callicarpa kochiana.

Abstract Previous studies revealed that diterpenoids from Callicarpa genus were mainly of clerodane-type and phyllocladane-type, and abietane-type diterpenoids were seldom reported. In this paper, we reported two new abietane diterpenoids, kochianic acid A ( 1 ) and kochianic acid B ( 2 ), together with two known abietane-type diterpenoids, pedunculatic acid B ( 3 ) and 7 α , 15-dihydroxydehydroabietic acid ( 4 ), which were all isolated from Callicarpa kochiana . The structures of the new compounds 1 and 2 were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, 1 H- 1 H COSY, ROESY and finally confirmed by single-crystal X-ray diffraction.