Tag Archives: homonuclear decoupling

SeRMN presentations at the 2014 Ibero-American NMR & GERMN Bienal & Iberian NMR meeting

Imagen1Some of our last research work will be presented next week at the VI Ibero-American NMR – VII GERMN Bienal – IV Iberian NMR joint meeting that will take place in Alcalá de Henares, Madrid (Spain) from 22nd to 25th September. Find below a summary of our contributions.

Laura Castañar presents an oral communication and a poster entitled “Enantiodifferentiation throgh frequency-selective pure shift 1H NMR”.  NMR-aided discrimination of enantiomers using chiral solvating agents (CSAs) is a well established method to carry out enantiodifferentiation studies. Continue reading SeRMN presentations at the 2014 Ibero-American NMR & GERMN Bienal & Iberian NMR meeting

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

CoverIssue“Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra” by Miriam Pérez-Trujillo, Laura Castañar, Eva Monteagudo, Lars T. Kuhn, Pau Nolis, Albert Virgili, R. Thomas Williamson and Teodor Parella. Chemical Communications  50:10214-10217 (2014). DOI: 10.1039/C4CC04077E

NMR-aided discrimination of enantiomers using chiral solvating agents (CSAs) is a well established method of enantiodifferentiation and measurement of enantiomeric ratios (er). The analysis is traditionally performed by observing chemical shift differences (ΔΔδ) in 1H signals by conventional 1D 1H NMR spectra. However, low ΔΔδ values and signal overlap caused by complex multiplets lead to the lack of spectral signal dispersion that preclude a straightforward analysis. Continue reading Simultaneous 1H and 13C NMR enantiodifferentiation from highly-resolved pure shift HSQC spectra

Presentations at the EUROMAR 2014 Conference

EUROMAR 2014

In a few days several SeRMN members will present our research work at the annual meeting of the European magnetic resonance community EUROMAR 2014 Conference  that will take place in Zurich (Switzerland) from 29th June to 3th July. Find below a summary of our contributions. Continue reading Presentations at the EUROMAR 2014 Conference

HOBS experiments to measure T1/T2 relaxation times in overlapped regions

S10907807“Measurement of T1/T2 relaxation times in overlapped regions from homodecoupled 1H singlet signals” by Laura Castañar, Pau Nolis, Albert Virgili and Teodor Parella. Journal of Magnetic Resonance 244 (2014) 30-35. DOI: 10.1016/j.jmr.2014.04.003

The implementation of the HOmodecoupled Band-Selective (HOBS) technique in the conventional Inversion-Recovery and CPMG-based PROJECT experiments is described. The achievement of fully homodecoupled signals allows the distinction of overlapped 1H resonances with small chemical shift differences. It is shown that the corresponding T1 and T2 relaxation times can be individually measured from the resulting singlet lines using conventional exponential curve-fitting methods. Continue reading HOBS experiments to measure T1/T2 relaxation times in overlapped regions

HOBS Applications

SeRMN seminar

  • Date:  Friday 28th March, 2014
  • Hour: 12 am
  • Location:  SeRMN,  Facultats de Ciències i Biociències, C2/-135
  • Speaker:  Laura Castañar, SeRMN PhD Student & Teaching Assistant, Dept. of Chemistry.

HOBS Applications (27-03-2014)

Several NMR applications using HOmodecouped Band-Selective NMR experiments [1] are proposed. The easy implementation of this HOBS scheme as a general building block into a great variety of multidimensional NMR experiments leads to pure-shift spectra with enhanced resolution and with the maximum attainable sensitivity. In this talk is presented the application of HOBS for measuring direct [1] and long-range [2] heteronuclear coupling constants. Also the use of HOBS experiments to enantiodiscrimination studies are presented [3].

Reference:

[1] “Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments” by L. Castañar, P. Nolis, A. Virgili and T. ParellaChem. Eur. J. 2013, 19, 17283-17286. DOI: 10.1002/chem.201303235

[2]Implementing homo- and heterodecoupling in region-selective HSQMBC experiments” by Laura CastañarJosep Sauri, Pau Nolis,Albert Virgili and Teodor ParellaJournal of Magnetic Resonance,2014, 238, 63-69.  DOI:10.1016/j.jmr.2013.10.022
 
[3] “Enantiodifferentiation through Frequency-Selective Pure-Shift 1H Nuclear Magnetic Resonance Spectroscopy” by Laura CastañarMíriam Pérez-Trujillo, Pau Nolis, Eva MonteagudoAlbert Virgili and Teodor ParellaChemPhysChem, 2014. DOI: 10.1002/cphc.201301130

Continue reading HOBS Applications

Rapid and efficient enantiodifferentiation through frequency-selective pure-shift 1H NMR spectroscopy

cover“Enantiodifferentiation through Frequency-Selective Pure-Shift 1H Nuclear Magnetic Resonance Spectroscopy” by Laura Castañar, Míriam Pérez-Trujillo, Pau Nolis, Eva Monteagudo, Albert Virgili and Teodor Parella. ChemPhysChem,15 (2014) 854-857.

DOI: 10.1002/cphc.201301130

A frequency-selective 1D 1H NMR experiment for the fast and sensitive determination of  chemical shift differences between overlapped resonances is proposed. The resulting fully homodecoupled 1H resonances appear as resolved 1D singlets without their typical JHH multiplet structure. The achieved high signal dispersion is here exploited in  enantiodiscrimination studies using chiral solvating agents. Continue reading Rapid and efficient enantiodifferentiation through frequency-selective pure-shift 1H NMR spectroscopy

Pure Shift NMR & HOBS Experiments

SeRMN seminar

  • Date:  Monday 16th December, 2013
  • Hour: 10 am
  • Location:  SeRMN,  Facultats de Ciències i Biociències, C2/-135
  • Speaker:  Laura Castañar, SeRMN PhD Student & Teaching Assistant, Dept. of Chemistry.

Pure Shift NMR Spectroscopy (05-09-2013)

A NMR pulse scheme that provides full sensitivity in homodecouped band-selective NMR experiments is proposed. Continue reading Pure Shift NMR & HOBS Experiments

Implementing homo- and heterodecoupling in region-selective HSQMBC experiments

S10907807Implementing homo- and heterodecoupling in region-selective HSQMBC experiments” by Laura Castañar, Josep Sauri, Pau Nolis, Albert Virgili and Teodor ParellaJournal of Magnetic Resonance 238 (2014) 63-69.
DOI: 10.1016/j.jmr.2013.10.022
 

A NMR method to enhance the sensitivity and resolution in band-selective long-range heteronuclear correlation spectra is proposed. The excellent in-phase nature of the selHSQMBC experiment allows that homonuclear and/or heteronuclear decoupling can be achieved in the detected dimension of a 2D multiple-bond correlation map, obtaining simplified cross-peaks without their characteristic fine J multiplet structure. The experimental result is a resolution improvement while the highest sensitivity is also achieved. Specifically, it is shown that the 1H-homodecoupled band-selective (HOBS) HSQMBC experiment represents a new way to measure heteronuclear coupling constants from the simplified in-phase doublets generated along the detected dimension.

abstract

Pulse Programs Code for Bruker:

Data set Example:

References:

“Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments” by L. Castañar, P. Nolis, A. Virgili and T. Parella. Chem. Eur. J. 2013, 19, 17283-17286. DOI: http://dx.doi.org/10.1002/chem.201303235

Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments

cover“Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments” by Laura Castañar, Pau Nolis, Albert Virgili and Teodor Parella. Chem. Eur. J. 2013, 19, 17283-17286.

DOI: 10.1002/chem.201303235

 

A NMR pulse scheme that provides full sensitivity in homodecouped band-selective NMR experiments is proposed. Continue reading Full sensitivity and enhanced resolution in homodecoupled band-selective NMR experiments