HSQC-TOCSY experiment

Nolls, P., Parella, T. Spin-edited 2D HSQC-TOCSY experiments for the measurement of homonuclear and heteronuclear coupling constants application to carbohydrates and peptides. /. Magn. Reson. 2005, 176, 15-26. 

Load the spectrum of the gradient-assisted, inverse detected, 2D CH-HSQC-TOCSY experiment acquired with the echo-antiecho technique, D NMRDATA GLUCOSE 2D CH GCHICOTO 001999.RR. Check and if necessary correct its calibration in both dimensions. Set up a layout as for the basic HSQC spectrum. Compare the spectrum with the spectra of the basic HSQC and HMQC experiments. Use the same rows or columns to identify the additional TOCSY-peaks. 

A second natural product study reported in 2003 that used the sensitivity of cryogenic probe capabilities and the HSQC-TOCSY experiment to advantage was the report by Preiss et al.25S that detailed the elucidation of the structure of two new asterosaponins from the starfish Asterias rubens. The structure of one of the molecules characterized (110) of which only 0.3 mg was isolated, is shown. 

In addition to sensitivity-improved two-dimensional TOCSY experiments, PEP versions of two-dimensional HSQC-TOCSY experiments (Cavanagh et al., 1991) as well as three-dimensional HSQC-TOCSY and three-dimensional TOCSY-HMQC experiments (Palmer et al., 1992 Ranee, 1994 Krishnamurthy, 1995) have been reported. This enhancement scheme is also used in heteronuclear coherence-order-selective coherence transfer (COS-CT Schleucher et al., 1994 Sattler et al., 1995a). Because in... 

Parameters for the HSQC-TOCSY experiment are the same as for the component HSQC and TOCSY experiments ... 

Their work was based, in part, on the ID HSQC-TOCSY experiment. In general, the authors have utilized the Preservation of Enhanced Pathways (PEP) approach in the development of the sequences that they have described. The HSQC-TOCSY based experiments, of course, mandate a protonated resonance. The authors have, however, also proposed a HSQMBC experiment in which the heteronuclear... 

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