Four triterpenoids bearing α,β-unsaturated A-ring functionality have been prepared from betulin, an abundant and readily isolated triterpene found in the bark of birch (Betula spp.). These compounds were evaluated as antifeedants in laboratory leaf-disk choice assays against bollworm larvae, Heliothis zea. One triterpenoid, 19(β,28-epoxy-2-(β-D-glucopyranosyloxy)-18α-olean-l-en-3-one (VIII), was found to display high antifeedant activity.
All Science Journal Classification (ASJC) codes
- Agricultural and Biological Sciences(all)