Isolation and structure elucidation of four new dihydro-β-agarofuran polyesters from Euonymus sachalinensis
Abstract
Four new dihydro-β-agarofuran polyesters 1–4 have been isolated from the fruit of Euonymus sachalinensis(Celastraceae) and their structures elucidated by means of 1H and 13C NMR spectroscopy, including 1H–1H COSY, DEPT, 1H–13C COSY and COLOC measurements, mass spectrometry and chemical reactions. The configurations have been determined on the basis of NOESY spectra and X-ray analysis. The isolated compounds are the first native representatives of 3, 12-oxygenated dihydro-β-agarofuran in which the usual macrocycle is missing. The structural similarity of compounds 1–4 and the macrocyclic derivatives is noteworthy from a biogenetic point of view.