NMR analysis of the trisaccharide 2′‐fucosyllactose by heteronuclear trans‐glycosidic coupling constants and molecular simulations

Abstract

Abstract1H, 13C NMR coupling constants across the glycosidic linkages were measured for the trisaccharide α‐L‐Fucp‐(1→2)‐β‐D‐Galp‐(1→4)‐D‐Glcp from human milk and its reduced analogue α‐L‐Fucp‐(1→2)‐β‐D‐Galp‐(1→4)‐D‐Glucitol employing one‐dimensional multiple‐site 13C excitation experiments. Hadamard spectroscopy and pulsed field gradients were also used with or without band‐selective 1H decoupling during the acquisition period. The experimental scalar coupling constants were compared to those calculated from Langevin dynamics simulations employing different molecular mechanics force fields. An analysis of 3J(C,H) values determined with this NMR technique on di‐ and trisaccharides is also performed. Copyright © 2001 John Wiley & Sons, Ltd.