Hello,I'm trying to set up an experiment to measure C-C coupling constants:1. Do I understand it right that the standard 1D INADEQUATE pulse sequence inad1d would give me quite and accurate measurement of 1J(C-C) constants and the resulting spectrum can be treated similarly to a regular 1H spectrum, i.e. if the carbon in question is a secondary one, its signal will come out as a doublet of doublets?
2. What's the easiest method to measure long-range C-C coupling constant? I have read about SELINQUATE, J-modulated ADEQUATE, GRECCO and modified refocused INADEQUATE (JMR A vol. 122, 245, 1996), but I could not find any of these in the standard Bruker pulse program list. How to set up any of these? Thank you for your time!
Check if somebody has answered this question on NMRWiki QA forum
Did you find this post helpful? |
Similar Threads
Thread
Thread Starter
Forum
Replies
Last Post
[U. of Ottawa NMR Facility Blog] Measurement of Long Range C H Coupling Constants
Measurement of Long Range C H Coupling Constants
The stereochemistry of compounds is assigned very often with proton - proton NOE's by applying the 2D NOESY technique or the 1D selective gradient NOESY technique. These methods fail, however when the distance between protons is too large to measure an NOE. When faced with this situation, it may be possible to measure long range proton - carbon coupling constants which are able to provide the necessary information. Three-bond carbon - proton couplings follow a Karplus relationship where the magnitude of the coupling constant is related to...
nmrlearner
News from NMR blogs
0
08-17-2012 10:44 PM
On the calculation of 3Jαβ-coupling constants for side chains in proteins
On the calculation of 3Jαβ-coupling constants for side chains in proteins
Abstract Structural knowledge about proteins is mainly derived from values of observables, measurable in NMR spectroscopic or X-ray diffraction experiments, i.e. absorbed or scattered intensities, through theoretically derived relationships between structural quantities such as atom positions or torsional angles on the one hand and observable quantities such as squared structure factor amplitudes, NOE intensities or 3 J-coupling constants on the other. The standardly used relation connecting 3 J-couplings...
nmrlearner
Journal club
0
06-25-2012 04:41 AM
More accurate 1JCH coupling measurement in the presence of 3JHH strong coupling in natural abundance
More accurate 1JCH coupling measurement in the presence of 3JHH strong coupling in natural abundance
Publication year: 2012
Source:Journal of Magnetic Resonance, Volume 215</br>
Bingwu Yu, Hugo van Ingen, Subramanian Vivekanandan, Christoph Rademacher, Scott E. Norris, Darón I. Freedberg</br>
J couplings are essential for measuring RDCs (residual dipolar couplings), now routinely used to deduce molecular structure and dynamics of glycans and proteins. Accurate measurement of 1 J CH is critical for RDCs to reflect the true structure and dynamics in the molecule of...
nmrlearner
Journal club
0
03-09-2012 09:16 AM
Conformational dependence of 13C shielding and coupling constants for methionine
Abstract Methionine residues fulfill a broad range of roles in protein function related to conformational plasticity, ligand binding, and sensing/mediating the effects of oxidative stress. A high degree of internal mobility, intrinsic detection sensitivity of the methyl group, and low copy number have made methionine labeling a popular approach for NMR investigation of selectively labeled protein macromolecules. However, selective labeling approaches are subject to more limited information content. In order to optimize the information available from such studies, we have performed DFT...
nmrlearner
Journal club
0
08-25-2010 03:51 PM
[NMR paper] The impact of direct refinement against three-bond HN-C alpha H coupling constants on
The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
Related Articles The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
J Magn Reson B. 1994 May;104(1):99-103
Authors: Garrett DS, Kuszewski J, Hancock TJ, Lodi PJ, Vuister GW, Gronenborn AM, Clore GM
nmrlearner
Journal club
0
08-22-2010 03:33 AM
[NMR paper] The impact of direct refinement against three-bond HN-C alpha H coupling constants on
The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
Related Articles The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
J Magn Reson B. 1994 May;104(1):99-103
Authors: Garrett DS, Kuszewski J, Hancock TJ, Lodi PJ, Vuister GW, Gronenborn AM, Clore GM
nmrlearner
Journal club
0
08-22-2010 03:33 AM
[U. of Ottawa NMR Facility Blog] E.COSY and the Relative Signs of Coupling Constants
E.COSY and the Relative Signs of Coupling Constants
Spin-spin coupling constants can have values greater than or less than zero. The absolute sign of the coupling constants cannot be discerned from the simple examination of a 1H NMR spectrum. The E.COSY1 (Exclusive COrrelation SpectroscopY) technique is one method which can be used to determine the relative signs of coupling constants. E.COSY is a phase sensitive COSY variant which produces off-diagonal signals showing only the active coupling (i.e. the coupling directly responsible for the cross-peak) as 2x2 antiphase square tetrads...