Sesquiterpenes fromMaytenus magellanica(Celastraceae)

Abstract
Five dihydro-β-agarofuran [5,11-epoxy-5β,10α-eudesm-4(14)-ene] sesquiterpenes, three of which have a novel substitution pattern were isolated from Maytenus magellanica and their structures were elucidated by means of 1H and 13C NMR spectroscopic studies, including 1H-13C heteronuclear correlation (HETCOR), long range correlation spectra with inversal detection (HMBC) and NOE experiments. Their absolute configurations were determined by application of the CD exciton chirality method while hydrolysis and preparation of derivatives provides additional information. Two of the sesquiterpenes exhibited significant antifeedant activity against Spodoptera littoralis.