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

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 7α, 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, 1H-1H COSY, ROESY and finally confirmed by single-crystal X-ray diffraction.

Graphical abstractTwo new abietane diterpenoids kochianic acid A (1) and kochianic acid B (2) were isolated from the caulis and leaves of Callicarpa kochiana Makino., their structures were finally confirmed by single-crystal X-ray diffractionFigure optionsDownload full-size imageDownload high-quality image (206 K)Download as PowerPoint slide