Antinematodal activities of ingenane diterpenes from Euphorbia kansui and their derivatives against the pine wood nematode (Bursaphelenchus xylophilus)

Abstract

Under the bioassay-guided method, two diterpenes, 3-O-(2″,3″- dimethylbutanoyl)-13-O-dodecanoylingenol (1) and 3-O-(2″,3″- dimethylbutanoyl)-13-O-decanoylingenol (2) isolated from Euphorbia kansui, showed a pronounced antinematodal activity against the nematode Bursaphelenchus xylophilus at the same minimum effective dose (MED) of 5 μg per cotton ball and still displayed antinematodal activity at a dose of 2.5 μg per cotton ball. Compounds 3-6 were obtained, and the structure of the new compound 6 was elucidated based on 1D-and 2D-NMR analyses and physicochemical data. Preliminary structure-biological activity relationships of ingenane-type compounds were deduced. © 2008 Verlag der Zeitschrift für Naturforschung.