Billavanones, flavonoids, and coumarins from the roots of Stellera chamaejasme and their antiviral effect on hepatitis B virus

A new 3,3-biflavanone, isosikokianin A (1), was isolated from the roots of Stellera chamaejasme, together with eleven known compounds. Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR techniques. Sikokianin A, chamaechromone, and quercetin showed in vitro antiviral activity against HBsAg secretion.