Cephalotane-type C 20 diterpenoids from Cephalotaxus fortunei var. alpina .

Seventeen new cephalotane-type diterpenoids, fortalides A-Q (1-17), along with five known analogues, were isolated from the seeds of Cephalotaxus fortunei var. alpina . Their structures were determined by extensive spectroscopic methods, as well as electronic circular dichroism (ECD) and X-ray crystallographic data analyses. Some isolates exhibited unusual structural features that were first found in cephalotane-type diterpenoids, such as the occurrence of the 7-oxabicyclo[4.1.1]octane moiety in 14 and 15 and the cis -arrangement of 3-OH and Me-19 in 9. Besides, the antiplasmodial activity of these compounds was evaluated in this study.