Pure Shift & Time-sharing
Broadband Homodecoupled Time-Shared 1H-13C and 1H-15N HSQC Experiments

P. Nolis, K. Motiram-Corral, M. Pérez-Trujillo and T. Parella

J. Magn. Reson, 298, 23-30 (2019). DOI

The concepts of pure-shift NMR and time-shared NMR are merged in a single experiment. A 13C/15N time-shared version of the real-time BIRD-based broadband homodecoupled HSQC experiment is described. This time-efficient approach affords simultaneously 1H-13C and 1H-15N pure-shift HSQC spectra in a single acquisition, while achieving substantial gains in both sensitivity and spectral resolution. We also present a related 13C/15N-F2-coupled homodecoupled version of the CLIP-HSQC experiment for the simultaneous measurement of 1JCH and 1JNH from the simplified doublets observed along the direct dimension. Finally, a novel J-resolved HSQC experiment has been designed for the simple and automated determination of both 1JCH/1JNH from a 2D J-resolved spectrum. More info ...


Pure Shift NMR Covariance
Access to experimentally infeasible spectra by pure-shift NMR Covariance

A. Fredi, P. Nolis, C. Cobas and T. Parella

J. Magn. Reson, 270, 161-168 (2016). DOI

Covariance processing is a versatile processing tool to generate synthetic NMR spectral representations without the need to acquire time-consuming experimental datasets. Here we show that even experimentally prohibited NMR spectra can be reconstructed by introducing key features of a reference 1D CHn-edited spectrum into standard 2D spectra. This general procedure is illustrated with the calculation of experimentally infeasible multiplicity-edited pure-shift NMR spectra of some very popular homonuclear (ME-psCOSY and ME-psTOCSY) and heteronuclear (ME-psHSQC-TOCSY and ME-psHMBC) experiments. More info ...


Pure Shift NMR Covariance
Exploring the use of Generalized Indirect Covariance to reconstruct pure shift NMR spectra: Current Pros and Cons

A. Fredi, P. Nolis, C. Cobas, G.E. Martin and T. Parella

J. Magn. Reson, 266, 16-22 (2016). DOI

The current Pros and Cons of a processing protocol to generate pure chemical shift NMR spectra using Generalized Indirect Covariance are presented and discussed. The transformation of any standard 2D homonuclear and heteronuclear spectrum to its pure shift counterpart by using a reference DIAG spec- trum is described. Reconstructed pure shift NMR spectra of NOESY, HSQC, HSQC-TOCSY and HSQMBC experiments are reported for the target molecule strychnine. More info ...


NMR Enantiodifferentiation
Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra

M. Pérez-Trujillo, L. Castañar, E. Monteagudo, L. T. Kuhn, P. Nolis, A Virgili, R.T. Williamson and T. Parella,

Chemical Communications,
50, 10214 (2014). DOI

NMR enantiodifferentiation studies are greatly improved by the simultaneous determination of 1H and 13C chemical shift differences through the analysis of highly resolved cross-peaks in spectral aliased pure shift (SAPS) HSQC spectra.  More info ...


Ultra high-resolved NMR
Ultra high-resolution HSQC: Application to the efficient and accurate measurement of heteronuclear coupling constants

N. Marcó, A. Fredi and T. Parella

Chem. Comm., 51, 3262-3265 (2015). DOI

A rapid NMR data acquisition strategy in terms of enhanced resolution per time unit for the simple and efficient determination of multiple coupling constants is described. The use of 13C spectral aliasing combined by broadband 1H homodecoupling allows accurate measurements from ultra high resolved 2D HSQC cross-peaks. More info ....

Slice-selective NMR
Simultaneous Multi-Slice Excitation in Spatially Encoded NMR Experiments

L. Castañar, P. Nolis, A Virgili and T. Parella,

Chem. Eur. J.,
19, 15472 (2013). DOI

An improved data collection technique with simultaneous multi-slice data acquisition has been presented. The sensitivity of slice-selective NMR experiments can be substantially improved by simultaneously applying a multiple-frequency pulse and spatial encoding gradient.

 The experimental procedure to fulfill the sampled frequency requirement is simple and the results can be inmediately adapted to a wide range of applications.  More info ...