Absolute configuration and conformational analysis of sesquiterpene lactone glycoside studied by vibrational circular dichroism spectroscopy

The absolute configuration of the guaiane-type sesquiterpene lactone 8-epiisolippidiol-3-O-β-d-glucopyranoside, isolated from plants of the genus Crepis, and the predominant solution-state conformation in CD3OD were determined by comparison of experimental and calculated VCD spectra. It has been found that the reported stereostructure of the compound corresponds to its absolute configuration.