MD CALCULATIONS ON NYSTOSE COMBINED WITH NMR-SPECTROSCOPY ON INULIN RELATED OLIGOSACCHARIDES

Molecular Dynamics (MD) calculations have been performed on nystose in water. According to these calculations the glycosidic linkages of the molecule are flexible. Structures obtained with MD calculations are compared with NMR data of several inulin related oligosaccharides and inulin, resulting in a model for the conformation of their fructofuranosyl residues. To extend the set of available NMR data of inulin related oligosaccharides, the complete assignment of the H-1 and C-13 NMR signals of beta-D-fructofuranosyl-(2->1)-beta-D-fructofuranosyl-(2->1)-beta-D-fructofuranosyl-(2->1)-beta-D-fructofuranosyl-(2->1)-alpha-D-glucopyranoside has been given here, using several 2D homo- and heteronuclear NMR experiments. Accurate coupling constants have been obtained by simulation of the 600 MHz 1D NMR spectra.