New Pregnane Glycosides from Brucea javanica and Their Antifeedant Activity

Three new pregnane glycosides, 3‐O‐β‐D‐glucopyranosyl‐(1→2)‐α‐L‐arabinopyranosyl‐(20R)‐pregn‐5‐ene‐3β,20‐diol (1), 3‐O‐α‐L‐arabinopyranosyl‐(20R)‐pregn‐5‐ene‐3β,20‐diol‐20‐O‐β‐D‐glucopyranoside (2), 3‐O‐α‐L‐arabinopyranosyl‐(20R)‐pregn‐5‐ene‐3β,20‐diol‐20‐O‐β‐D‐glucopyranosyl‐(1→2)‐β‐D‐glucopyranoside (3) were isolated along with four known compounds, 4–7, from the leaves and stems of Brucea javanica. Their structures were determined by detailed analyses of 1D‐ and 2D‐NMR spectroscopic data. All of the compounds isolated from Brucea javanica were tested for the antifeedant activities against the larva of Pieris rapae. Compounds 1, 3, and 5 showed significant antifeedant activities after 72 h incubation.