Four new tetranortriterpenoids from cedrela odorata associated with leaf rejection by exopthalmus jekelianus

Four new tetranortriterpenoids, 3-deoxo-3beta,8beta-epoxy-6, 14alpha-dihydroxy-8,14-dihydromexicanolide (cedrodorin, 1); 3-deoxo-3beta,8beta-epoxy-6-acetoxy-14alpha-hydroxy-8, 14-dihydromexicanolide (6-acetoxycedrodorin, 2); 3-deoxo-3beta, 8beta-epoxy-6-deoxy-9alpha,14alpha-dihydroxy-8, 14-dihydromexicanolide (6-deoxy-9alpha-hydroxycedrodorin, 3); and 3-deoxo-3beta,8beta-epoxy-6,9alpha,14alpha-trihydroxy-8, 14-dihydromexicanolide (9alpha-hydroxycedrodorin, 4), have been isolated from the leaves of Cedrela odorata by HPLC. Their molecular structures were determined by 1D and 2D NMR. Three of the compounds are associated with leaf rejection by the polyphagous, folivorous weevil, Exopthalmus jekelianus. The importance of these compounds as insect deterrents in C. odorata, and their potential value in the selection of insect-resistant clones for timber plantations is discussed.