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Updated: Oct 20, 2025

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
Characterization of Mannosyl Dioxanium Ions in Solution Using Chemical Exchange Saturation Transfer NMR Spectroscopy
Frank F J de Kleijne1, Hidde Elferink1, Sam J Moons1
1Synthetic organic chemistry, Institute for molecules and materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
Abstract:
The stereoselective introduction of the glycosidic bond remains one of the main challenges in carbohydrate synthesis. Characterizing the reactive intermediates of this reaction is key to develop stereoselective glycosylation reactions. Herein we report the characterization of low-populated, rapidly equilibrating mannosyl dioxanium ions that arise from participation of a C-3 acyl group using chemical exchange saturation transfer (CEST) NMR spectroscopy. Dioxanium ion structure and equilibration kinetics were measured under relevant glycosylation conditions and highly α-selective couplings were observed suggesting glycosylation took place via this elusive intermediate.
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