The double‐DANTE sequence applied to NMR of complex carbohydrates

The double‐DANTE sequence was implemented in 1D TOCSY and NOESY experiments to overcome some typical problems in the NMR of carbohydrates. In the 1D TOCSY experiment the double‐DANTE sequence serves to invert simultaneously two resonances belonging to the same scalar‐coupled spin system, thereby substantially increasing the sensitivity of the technique for subspectral editing and providing a valuable alternative to relayed TOCSY in overcoming small‐J bottlenecks in monosaccharides such as galactose and sialic acid. Spin‐diffusion artifacts in 1D NOESY experiments that are mediated by more than one spin can be effectively eliminated by applying a double‐DANTE pulse train for saturation of the mediators during the mixing time. In certain cases, the double‐DANTE sequence is also capable of eliminating the three‐spin effect in 1D 13C{1H} NOE difference spectroscopy.