NEW MATERIAL:A carbon 13-membered ring cembranolide diterpen shown by the formula I (R' is H or lower alkanoyl; when R' is H, X is H2 and when R' is lower alkanoyl, X is O) or II (R" is lower alkoxy).
USE: A drug having antitumor action, hypotensive action, etc. Especially carcinostatic agent.
PROCESS: Lobophytum pauciflorum (Ehrenberg) is chopped into slices in an organic solvent, and extracted with methanol and acetone successively. Both the extracted solutions are dispersed in water and extracted with ether. The ether soluble part is subjected to silica gel chromatography, eluted with n-hexane-acetone (in a weight ratio of 20:1W1:1), and fractioned. An n-hexane-acetone (5:1) soluble part is further subjected to silica gel chromatography and eluted with ethyl acetate (20:1W 10:1) to give a crystalline substance shown by the formula I wherein R' is acetyl and X is H2.
KIKUCHI HIROYUKI
SHIBAYAMA FUMIO
HORIAI HARUO
NAKANISHI HAJIME
