New ways to measure and suppress 1H-1H couplings in 1H-13C experiments

Sinnaeve, Davy

Document type :

Communication dans un congrès avec actes

Permalink :

http://hdl.handle.net/20.500.12210/126790

Title :

New ways to measure and suppress 1H-1H couplings in 1H-13C experiments

Author(s) :

Sinnaeve, Davy [Orateur]

Facteurs de Risque et Déterminants Moléculaires des Maladies liées au Vieillissement - U 1167 [RID-AGE]
Biologie Structurale Intégrative [ERL 9002 - INSERM U1167 - BSI]

Conference title :

43rd FGMR Annual Discussion Meeting

Conference organizers(s) :

Division of Magnetic Resonance of the German Chemical society

City :

Karlsruhe

Country :

Allemagne

Start date of the conference :

2022-09-12

English keyword(s) :

NMR spectroscopy

HAL domain(s) :

Chimie/Chimie analytique

English abstract : [en]

In organic molecules, 1H-1H couplings are abundant and their measurement contributes greatly to constitutional, configurational and conformational structure elucidation studies. The downside of their abundance is that it ...
Show more >In organic molecules, 1H-1H couplings are abundant and their measurement contributes greatly to constitutional, configurational and conformational structure elucidation studies. The downside of their abundance is that it results in complex and broad multiplets that may overlap, obstructing extraction of individual couplings or other spectral information. Pure shift experiments alleviate the overlap problem by delivering fully homodecoupled 1H spectra, boosting spectral resolution by an order of magnitude [1]. They can elegantly be combined with selective 2D J-resolved experiments, such as SERF, G-SERF or PSYCHEDELIC [2], allowing individual coupling measurement at pure shift resolution. Unfortunately, in situations where coupled protons have very small chemical shift differences (strong coupling), pure shift and 2DJ methods often break down. A way to circumvent this issue is by focusing on the 13C isotopomer signals instead, since at natural abundance the large 1JCH coupling breaks the chemical shift degeneracy between protons relative to the all-12C isotopomer [3].I will first introduce a new selective 2DJ method that allows selective observation of the 13C isotopomer signals by making good use of the BIRD pure shift element [3]. This provides access to 1H-1H couplings unattainable with SERF or PSYCHEDELIC.Unfortunately, a major drawback of BIRD pure shift methods is that geminal 1H-1H couplings are not suppressed, which is especially problematic for compounds rich in methylene groups. This is a general limitation for pure shift 1H-13C HSQC experiments. Proposed solutions have been the use of constant-time acquisition, the perfect echo, or J-resolved echo processing [4-6], but all these methods have particular shortcomings that complicate their application under molecular alignment conditions, for medium to large size molecules, or for selective 2DJ experimental design.I will present a generally applicable pure shift method compatible with 1H-13C HSQC experiments that circumvents all aforementioned shortcomings at a reasonable price in sensitivity relative to the parent pure shift HSQC experiment. The new method, coined CYBORG, allows maximum pure shift resolution for 1H-13C HSQC experiments, holds promise for the study of larger compounds such as peptides or protein side-chains, and is easily combined with selective 2DJ methods.Literature:[1] K. Zangger, Prog. Nucl. Magn. Reson. Spectrosc. 2015, 86-87, 1. [2] D. Sinnaeve, eMagRes 2021, 9, 267. [3] J. Aguilar et al., Angew. Chem. Int. Ed. 2011, 50, 9716. [4] T. Reinsperger et al., J. Magn. Reson. 2014, 239, 110. [5] L. Kaltschnee et al., Chem. Commun. 2014, 50, 15702. [6] P. Sakhaii et al., Sci. Rep. 2021, 11, 21566.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

ANR Project :

RMN à haute résolution et anisotrope pour dévoiler des ensembles conformationnels de biopolymères flexibles : une stratégie générale

Collections :

Facteurs de risque et déterminants moléculaires des maladies liées au vieillissement (RID-AGE) - U1167

Source :

Harvested from HAL

Submission date :

2025-04-03T03:52:09Z

New ways to measure and suppress 1H-1H ... BibTeX CSV Excel RIS

New ways to measure and suppress 1H-1H ...

BibTeX

CSV

Excel

RIS