Astataricusones A–D and Astataricusol A, Five New Anti-HBV Shionane-Type Triterpenes from Aster tataricus L. f.

Five new shionane-type triterpenes, astataricusones A–D (compounds 1–4) and astataricusol A (5), together with one known shionane-type triterpene 6 were obtained from the roots and rhizomes of Aster tataricus L. f. Their structures were elucidated on the basis of spectroscopic data, mainly NMR and MS data. The absolute configurations of 1 and 4 was determined by single crystal X-ray diffraction and CD analysis. Compound 2 showed inhibitory activity on HBsAg secretion with an IC(50) value of 23.5 μM, while 2 and 6 showed inhibitory activities on HBeAg secretion with IC(50) values of 18.6 and 40.5 μM, and cytotoxicity on HepG 2.2.15 cells with CC(50) values of 172.4 and 137.7 μM, respectively. Compounds 2 and 6 also exhibited inhibitory activities on HBV DNA replication with IC(50) values of 2.7 and 30.7 μM, respectively.