Propindilactones E-J, schiartane nortriterpenoids from Schisandra propinqua var. propinqua

Six new nortriterpenoids, propindilatones E-J (1-6), and two known (7, 8) schiartane-type nortriterpenoids were isolated from the stems of Schisandra propinqua var. propinqua. Their structures were elucidated by extensive spectroscopic analyses, and the structure of compound 4 was confirmed through single-crystal X-ray diffraction. The absolute configuration of compounds 1-3 was established using CD methods. Compounds 4-6 were noncytotoxic against K562, A549, and HT-29 human cancer cells.