Tag Archives: full sensitivity

PhD Thesis: Development and application of modern pure shift NMR techniques and improved HSQC and HSQMBC experiments

Last 16st July 2015 I defended my PhD Thesis entitled: Development and application of modern pure shift NMR techniques and improved HSQC/HSQMBC experiments.

Presentación1

The present doctoral thesis is framed within the Nuclear Magnetic Resonance (NMR) spectroscopy field, more specifically in the design of modern NMR methodologies. The research work carried out is focused on the design and application of new and modern NMR methodologies (i) to perform efficient broadband 1H homodecoupling in 1D/2D NMR experiments and (ii) to accurately determine homo- and heteronuclear coupling constants in isotropic and anisotropic conditions through improved HSQC and HSQMBC-type experiments. The thesis is presented as a compendium ten (10) publications that have been published in several peer-reviewed international scientific journals as original research papers. Continue reading PhD Thesis: Development and application of modern pure shift NMR techniques and improved HSQC and HSQMBC experiments

PhD Thesis by Laura Castañar: Pulse Programs and Data Set Examples

Development and application of modern pure shift NMR techniques and improved HSQC/HSQMBC experiments

Presentación1

In the following links one can find Data Set Examples of each Publication presented in the Thesis Work, as well as the corresponding Pulse Program Code for Bruker. All 2D spectra have been previously phased and 2ii, 2ir, and 2ri files removed, otherwise data sets would be too big. Continue reading PhD Thesis by Laura Castañar: Pulse Programs and Data Set Examples

Review – Pure shift NMR experiments: recent developments, methods and applications

MRC_teo copy“Broadband 1H homodecoupled NMR experiments: recent developments, methods and applications” by Laura Castañar and Teodor Parella. Magnetic Resonance in Chemistry, 2015. DOI: 10.1002/mrc.4238

In recent years, a great interest in the development of new broadband 1H homonuclear decoupled techniques providing simplified JHH multiplet patterns has emerged again in the field of small molecule NMR. The resulting highly resolved 1H NMR spectra display resonances as collapsed singlets, therefore minimizing signal overlap and expediting spectral analysis. This review aims at presenting the most recent advances in pure shift NMR spectroscopy, with a particular emphasis to the Zangger–Sterk experiment. Continue reading Review – Pure shift NMR experiments: recent developments, methods and applications

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

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

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