1
|
Mishra SK, Suryaprakash N. Pure shift edited NMR methodologies for the extraction of Homo- and heteronuclear couplings with ultra-high resolution. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2023; 136-137:1-60. [PMID: 37716754 DOI: 10.1016/j.pnmrs.2023.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 01/20/2023] [Accepted: 02/01/2023] [Indexed: 09/18/2023]
Abstract
The scalar couplings that result in the splitting of the signals in the NMR spectrum arise due to the interaction of the nuclear spins, whereby the spin polarization is transmitted through chemical bonds. The interaction strengths depend inter alia on the number of consecutive chemical bonds intervening between the two interacting spins and on the molecular conformation. The pairwise interaction of many spins in a molecule resulting in a complex spectrum poses a severe challenge to analyse the spectrum and hence the determination of magnitudes and signs of homo- and heteronuclear couplings. The problem is more severe in the analysis of 1H spectra than the spectra of most of the other nuclei due to the often very small chemical shift dispersion. As a consequence, the straightforward analysis and the accurate extraction of the coupling constants from the 1H spectrum of a complex spin system continues to remain a challenge, and often may be a formidable task. Over the years, the several pure shift-based one-dimensional and two-dimensional methodologies have been developed by workers in the field, which provide broadband homonuclear decoupling of proton spectra, removing the complexity but at the cost of the very informative scalar couplings. To circumvent this problem, several one-dimensional and two-dimensional NMR experiments have been developed for the determination of homonuclear and heteronuclear couplings (nJHX, where n = 1,2,3) while retaining the high resolution obtained by implementing pure shift strategies. This review attempts to summarize the extensive work reported by a large number of researchers over the years for the accurate determination of homo- and heteronuclear scalar couplings.
Collapse
Affiliation(s)
- Sandeep Kumar Mishra
- Department of Physics and NMR Research Centre, Indian Institute of Science Education and Research, Pune 411008, India.
| | - N Suryaprakash
- NMR Research Centre and Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
| |
Collapse
|
2
|
Smith MJ, Gates EL, Widmalm G, Adams RW, Morris GA, Nilsson M. Resolving the complexity in human milk oligosaccharides using pure shift NMR methods and CASPER. Org Biomol Chem 2023; 21:3984-3990. [PMID: 37186244 DOI: 10.1039/d3ob00421j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Human milk oligosaccharides belong to an important class of bioactive molecules with diverse effects on the development of infants. NMR is capable of providing vital structural information about oligosaccharides which can aid in determining structure-function relationships. However, this information is often concealed by signal overlap in 1H spectra, due to the narrow chemical shift range and signal multiplicity. Signal overlap in oligosaccharide spectra can be greatly reduced, and resolution improved, by utilising pure shift methods. Here the benefits of combining pure shift methods with the CASPER computational approach to resonance assignment in oligosaccharides are demonstrated.
Collapse
Affiliation(s)
- Marshall J Smith
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
| | - Emma L Gates
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
| | - Göran Widmalm
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden
| | - Ralph W Adams
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
| | - Gareth A Morris
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
| | - Mathias Nilsson
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
| |
Collapse
|
3
|
McKay RT. Metabolomics and NMR. Handb Exp Pharmacol 2023; 277:73-116. [PMID: 36355220 DOI: 10.1007/164_2022_616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this manuscript will be to convince the reader to dive deeper into NMR spectroscopy and prevent the technique from being just another "black-box" in the lab. We will try to concisely highlight interesting topics and supply additional references for further exploration at each stage. The advantages of delving into the technique will be shown. The secondary objective, i.e., avoiding common problems before starting, will hopefully then become clear. Lastly, we will emphasize the spectrometer information needed for manuscript reporting to allow reproduction of results and confirm findings.
Collapse
Affiliation(s)
- Ryan T McKay
- Department Chemistry, College of Natural and Applied Sciences, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
4
|
Baishya B. Slice selective absorption-mode J-resolved NMR spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 342:107267. [PMID: 35853368 DOI: 10.1016/j.jmr.2022.107267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 07/04/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Limited chemical shift dispersion and broad multiplet patterns limit resolution in 1H NMR spectra. J-Resolved spectroscopy overcomes this problem to a great extent. However, the phase-twist line shape in J-Resolved spectroscopy allows only the magnitude mode of the experiment to be practical, which degrades resolution. Recently, various pure shift or broadband homonuclear decoupling approaches have been integrated with J-Resolved spectroscopy to eliminate the broad dispersive contribution. In the present work, we demonstrate a broadband 1H-1H J-Resolved spectrum with a greatly reduced dispersive contribution using the concept of slice selection. We show that slice selective excitation, t1 encoding, storage, and detection of the in-phase absorptive signals can be executed, while a gradient-based suppression of the dispersive antiphase signals can be performed during the storage period. In more than two spin systems, a small part of the doubly antiphase absorptive signal may also contribute to the spectrum in addition to the inphase absorptive signals. The overall effect is a reduced multiplet pattern similar to a regular J-Resolved case as the passive spins remain unflipped due to slice selective pulses. However, the effect is broadband for a fraction of the spins when all slices are considered analogous to Zangger-Sterk (ZS) broadband homo-decoupling. Further, the fresh magnetization from neighboring slices can be accessed in different scans by frequency shifting of the slice selective pulses without a recycle delay-an elegant aspect of the ZS pulse element. This allows faster signal averaging, improving sensitivity which depends on the T1 relaxation time of the signals. This method displays sensitivity up to 4-20 percent of the regular J-RES 1H signals.
Collapse
Affiliation(s)
- Bikash Baishya
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
| |
Collapse
|
5
|
Pure shift NMR and DFT methods for revealing long-range heteronuclear couplings. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
6
|
Sakhaii P, Bohorc B, Schliedermann U, Bermel W. Boosting the resolution of multidimensional NMR spectra by complete removal of proton spin multiplicities. Sci Rep 2021; 11:21566. [PMID: 34732770 PMCID: PMC8566458 DOI: 10.1038/s41598-021-01041-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 10/19/2021] [Indexed: 11/23/2022] Open
Abstract
Over decades multidimensional NMR spectroscopy has become an indispensable tool for structure elucidation of natural products, peptides and medium sized to large proteins. Heteronuclear single quantum coherence (HSQC) spectroscopy is one of the work horses in that field often used to map structural connectivity between protons and carbons or other hetero nuclei. In overcrowded HSQC spectra, proton multiplet structures of cross peaks set a limit to the power of resolution and make a straightforward assignment difficult. In this work, we provide a solution to improve these penalties by completely removing the proton spin multiplet structure of HSQC cross peaks. Previously reported sideband artefacts are diminished leading to HSQC spectra with singlet responses for all types of proton multiplicities. For sideband suppression, the idea of restricted random delay (RRD) in chunk interrupted data acquisition is introduced and exemplified. The problem of irreducible residual doublet splitting of diastereotopic CH2 groups is simply solved by using a phase sensitive JRES approach in conjunction with echo processing and real time broadband homodecoupling (BBHD) HSQC, applied as a 3D experiment. Advantages and limitations of the method is presented and discussed.
Collapse
Affiliation(s)
- Peyman Sakhaii
- NMR Laboratory of SANOFI, Global CMC Early Development, Synthetics Platform, Industrial Park Hoechst, Building G849, 65926, Frankfurt, Germany.
| | - Bojan Bohorc
- NMR Laboratory of SANOFI, Global CMC Early Development, Synthetics Platform, Industrial Park Hoechst, Building G849, 65926, Frankfurt, Germany
| | - Uwe Schliedermann
- NMR Laboratory of SANOFI, Global CMC Early Development, Synthetics Platform, Industrial Park Hoechst, Building G849, 65926, Frankfurt, Germany
| | - Wolfgang Bermel
- Bruker BioSpin GmbH, Silberstreifen 4, 76287, Rheinstetten, Germany
| |
Collapse
|
7
|
Ilgen J, Nowag J, Kaltschnee L, Schmidts V, Thiele CM. Gradient selected pure shift EASY-ROESY techniques facilitate the quantitative measurement of 1H, 1H-distance restraints in congested spectral regions. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 324:106900. [PMID: 33503522 DOI: 10.1016/j.jmr.2020.106900] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
For elucidating molecular structure and dynamics in solution, NMR experiments such as NOESY, ROESY and EXSY have been used excessively over the past decades, to provide interatomic distance restraints or rates for chemical exchange. The extraction of such information, however, is often prohibited by signal overlap in these spectra. To reduce this problem, pure shift methods for improving the spectral resolution have become popular. We report on pure shift EASY-ROESY experiments and their application to extract cross-relaxation rates, proton-proton distances and exchange rates. Homonuclear decoupling (pure shift) is applied in the indirect dimension using the PSYCHE or the perfectBASH technique, to enhance the spectral resolution of severely overcrowded spectral regions. The spectral quality is further improved by using a gradient selected F1-PSYCHE-EASY-ROESY, which produces significantly less t1-noise than the experiment used previously, as also demonstrated by employing the recently introduced SAN (signal-artefact-noise) plots. Applications include the quantification of distance restraints in a peptide organocatalyst and the extraction of a number of distance restraints in cyclosporine A, which were previously not available for analysis, because they were either located in overcrowded spectral regions or hidden under t1-noise. Distances extracted and exchange rates obtained are accurate. Also, the 2D gradient-selected F1-perfectBASH-EASY-ROESY with the additional gradient selection proposed herein, which is superior in terms of sensitivity, can be used to accurately quantify cross-relaxation.
Collapse
Affiliation(s)
- Julian Ilgen
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Jens Nowag
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Lukas Kaltschnee
- Max-Planck-Institut für Biophysikalische Chemie, Am Fassberg 11, 37077 Göttingen, Germany; Center for Biostructural Imaging of Neurodegeneration (BIN), Von-Siebold-Str. 3a, 37075 Göttingen, Germany
| | - Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany.
| |
Collapse
|
8
|
Singh U, Bhattacharya S, Baishya B. Pure shift HMQC: Resolution and sensitivity enhancement by bilinear rotation decoupling in the indirect and direct dimensions. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 311:106684. [PMID: 31931343 DOI: 10.1016/j.jmr.2020.106684] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/26/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
The heteronuclear multiple-quantum coherence in the indirect dimension of the two-dimensional HMQC experiment evolves under the passive 1H-1H J-couplings leading to multiplet structures in the F1 dimension. Besides, 1H-1H J-multiplets appear in the direct dimension as well. Thus, multiplets along both dimensions lower the resolution and sensitivity of this technique, when high resolution is required along both dimensions. An efficient broadband homodecoupling scheme along the F1 dimension of the HMQC experiment has not been realized to date. We have implemented broadband homonuclear decoupling using bilinear rotation decoupling (BIRD) by adding a 1H SQ evolution period followed by BIRD before the 1H-13C multiple-quantum evolution period in the HMQC. In the direct time domain, BIRD is implemented using a real-time or single-scan scheme, which further improves resolution and sensitivity of this technique. The resulting pure shift HMQC provides singlet peak per chemical site along F1 as well as F2 axes and, hence, better resolution and sensitivity than conventional HMQC spectrum for all peaks except diastereotopic methylene protons. Due to the incorporation of the BIRD, the indirect time domain becomes double in length compared to the conventional HMQC. However, slow relaxation of small molecules favors better sensitivity for ps-HMQC relative to conventional HMQC under all conditions. We also found that the sensitivity of ps-HMQC is only slightly less than ps-HSQC for small molecules.
Collapse
Affiliation(s)
- Upendra Singh
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India; Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India
| | - Subrato Bhattacharya
- Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India
| | - Bikash Baishya
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
| |
Collapse
|
9
|
Haller JD, Bodor A, Luy B. Real-time pure shift measurements for uniformly isotope-labeled molecules using X-selective BIRD homonuclear decoupling. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 302:64-71. [PMID: 30965191 DOI: 10.1016/j.jmr.2019.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 03/28/2019] [Accepted: 03/29/2019] [Indexed: 06/09/2023]
Abstract
We introduce a novel selective inversion element for chunked homonuclear decoupling that combines isotope selection via BIRD-filtering with band-selective inversion on the X-heteronucleus and allows efficient real-time decoupling of homonuclear and heteronuclear couplings. It is especially suitable for uniformly isotope-labeled compounds. We discuss in detail the inversion element based on band-selective refocusing on the X-nuclei (BASEREX), highlighting in particular the role of appropriate band-selective shaped refocusing pulses and the application of broadband X-pulses for an effective BIRDd element during homodecoupling. The approach is experimentally verified and studied in detail using uniformly 13C-labeled glucose and a uniformly 15N,13C-labeled amino acid mixture.
Collapse
Affiliation(s)
- Jens D Haller
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz, Karlsruher Institut für Technologie (KIT), Fritz-Haber-Weg 6, 76133 Karlsruhe, Germany
| | - Andrea Bodor
- Eötvös Loránd University, Institute of Chemistry, Laboratory of Structural Chemistry and Biology, Pázmány Péter sétány 1/a, Budapest 1117, Hungary
| | - Burkhard Luy
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz, Karlsruher Institut für Technologie (KIT), Fritz-Haber-Weg 6, 76133 Karlsruhe, Germany.
| |
Collapse
|
10
|
Timári I, Wang C, Hansen AL, Costa dos Santos G, Ok Yoon S, Bruschweiler-Li L, Brüschweiler R. Real-Time Pure Shift HSQC NMR for Untargeted Metabolomics. Anal Chem 2019; 91:2304-2311. [PMID: 30608652 PMCID: PMC6386528 DOI: 10.1021/acs.analchem.8b04928] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Sensitivity and resolution are key considerations for NMR applications in general and for metabolomics in particular, where complex mixtures containing hundreds of metabolites over a large range of concentrations are commonly encountered. There is a strong demand for advanced methods that can provide maximal information in the shortest possible time frame. Here, we present the optimization and application of the recently introduced 2D real-time BIRD 1H-13C HSQC experiment for NMR-based metabolomics of aqueous samples at 13C natural abundance. For mouse urine samples, it is demonstrated how this real-time pure shift sensitivity-improved heteronuclear single quantum correlation method provides broadband homonuclear decoupling along the proton detection dimension and thereby significantly improves spectral resolution in regions that are affected by spectral overlap. Moreover, the collapse of the scalar multiplet structure of cross-peaks leads to a sensitivity gain of about 40-50% over a traditional 2D HSQC-SI experiment. The experiment works well over a range of magnetic field strengths and is particularly useful when resonance overlap in crowded regions of the HSQC spectra hampers accurate metabolite identification and quantitation.
Collapse
Affiliation(s)
- István Timári
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Cheng Wang
- Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio 43210, United States
| | - Alexandar L. Hansen
- Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio 43210, United States
| | - Gilson Costa dos Santos
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Sung Ok Yoon
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Lei Bruschweiler-Li
- Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio 43210, United States
| | - Rafael Brüschweiler
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio 43210, United States
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, Ohio 43210, United States
| |
Collapse
|
11
|
Nolis P, Motiram-Corral K, Pérez-Trujillo M, Parella T. Broadband homodecoupled time-shared 1H- 13C and 1H- 15N HSQC experiments. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 298:23-30. [PMID: 30502625 DOI: 10.1016/j.jmr.2018.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/19/2018] [Accepted: 11/20/2018] [Indexed: 06/09/2023]
Abstract
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.
Collapse
Affiliation(s)
- Pau Nolis
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Catalonia, Spain
| | - Kumar Motiram-Corral
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Catalonia, Spain
| | - Míriam Pérez-Trujillo
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Catalonia, Spain
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Catalonia, Spain.
| |
Collapse
|
12
|
Parella T. Towards perfect NMR: Spin-echo versus perfect-echo building blocks. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2019; 57:13-29. [PMID: 29927497 DOI: 10.1002/mrc.4776] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/10/2018] [Accepted: 06/12/2018] [Indexed: 06/08/2023]
Abstract
The development of new tools to improve the quality of nuclear magnetic resonance (NMR) spectra is a challenging task. The concept of "perfect NMR" includes the design of robust pulse sequences that allow an investigator to obtain undistorted pure in-phase signals, with pure absorption lineshapes that are free of phase anomalies derived from undesired J modulations. Here, alternative NMR building blocks to the spin-echo that are based on a general double SE module, known as a perfect-echo, are reviewed. Several implementations to minimize/remove unwanted dispersive contributions in homonuclear and heteronuclear NMR experiments are described and illustrated with some examples of broad interest for small molecules.
Collapse
Affiliation(s)
- Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, Barcelona, Catalonia, Spain
| |
Collapse
|
13
|
Lin Y, Zeng Q, Lin L, Chen Z, Barker PB. High-resolution methods for the measurement of scalar coupling constants. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 109:135-159. [PMID: 30527134 DOI: 10.1016/j.pnmrs.2018.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 08/14/2018] [Accepted: 08/14/2018] [Indexed: 06/09/2023]
Abstract
Scalar couplings provide important information regarding molecular structure and dynamics. The measurement of scalar coupling constants constitutes a topic of interest and significance in NMR spectroscopy. However, the measurement of J values is often not straightforward because of complex signal splitting patterns and signal overlap. Many methods have been proposed for the measurement of scalar coupling constants, both for homonuclear and heteronuclear cases. Different approaches to the measurement of scalar coupling constants are reviewed here with several applications presented. The accurate measurement of scalar coupling constants can greatly facilitate molecular structure elucidation and the study of molecule dynamics.
Collapse
Affiliation(s)
- Yanqin Lin
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, Fujian 361005, China.
| | - Qing Zeng
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, Fujian 361005, China
| | - Liangjie Lin
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, Fujian 361005, China
| | - Zhong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, Fujian 361005, China
| | - Peter B Barker
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205, USA
| |
Collapse
|
14
|
Kiraly P, Nilsson M, Morris GA. Practical aspects of real-time pure shift HSQC experiments. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:993-1005. [PMID: 29274287 PMCID: PMC6175388 DOI: 10.1002/mrc.4704] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/12/2017] [Accepted: 12/13/2017] [Indexed: 05/28/2023]
Abstract
Pure shift NMR spectroscopy has become an efficient tool for improving resolution in proton NMR spectra by removing the effect of homonuclear couplings. The introduction of real-time acquisition methods has allowed the main drawback of pure shift NMR, the long experiment times needed, to be circumvented. Real-time methods use periodic application of J-refocusing pulse sequence elements, acquiring a single free induction decay, in contrast to previous methods that construct a pure shift interferogram by concatenating excerpts from multiple free induction decays. In the important heteronuclear single-quantum correlation experiment, implementing real-time pure shift data acquisition typically leads to the simultaneous improvement of both resolution and sensitivity. The current limitations of and problems with real-time pure shift acquisition methods are discussed here in the context of heteronuclear single-quantum correlation experiments. We aim to provide a detailed account of the technical challenges, together with a practical guide to exploiting the full potential of such methods.
Collapse
Affiliation(s)
- Peter Kiraly
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - Mathias Nilsson
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - Gareth A. Morris
- School of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| |
Collapse
|
15
|
Görling B, Bermel W, Bräse S, Luy B. Homonuclear decoupling by projection reconstruction. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:1006-1020. [PMID: 30058249 DOI: 10.1002/mrc.4784] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/16/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Similar to J-resolved spectroscopy, also, heteronuclear multiple bond correlation (HMBC), heteronuclear single bond correlation (HSBC), and heteronuclear multiple quantum coherence (HMQC) types of correlation experiments result in homonuclear tilted multiplet patterns. On the example of the high-resolution heteronuclear single bond correlation (HR-HSBC) pulse sequence, it is shown how the tilt angle can be varied within a wide range of positive and negative values. Projection along the tilt angles in all cases results in homonuclear decoupling. Using well-known projection reconstruction techniques, the different tilt angles can be used to reconstruct a homonuclear decoupled two-dimensional correlation spectrum. The concept is proven and further refined by segmental projection reconstruction and the use of a clean in-phase heteronuclear single quantum correlation (CLIP-HSQC) spectrum with an effective zero tilt angle for further filtering. The proof of principle, its application to one-bond coupling measurement, as well as a basic HMBC, and a detailed discussion with comparison to other homodecoupling techniques are given.
Collapse
Affiliation(s)
- Benjamin Görling
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- Institute for Biological Interfaces 4 - Magnetic Resonance, Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
- Bruker Biospin GmbH, Rheinstetten, Germany
| | | | - Stefan Bräse
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Burkhard Luy
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- Institute for Biological Interfaces 4 - Magnetic Resonance, Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany
| |
Collapse
|
16
|
Ilgen J, Kaltschnee L, Thiele CM. perfectBASH: Band-selective homonuclear decoupling in peptides and peptidomimetics. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:918-933. [PMID: 29885093 DOI: 10.1002/mrc.4757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/14/2018] [Accepted: 05/29/2018] [Indexed: 06/08/2023]
Abstract
Band selective techniques offer the highest sensitivity of all pure shift approaches and thus are the best choice for decoupling well-separated 1 H-frequency regions, such as the amide- or the α-proton region of α-peptides. They are inept to fully decouple the amide- and the α-proton region simultaneously, though. Herein, we present a new homonuclear decoupling technique, which extends the capabilities of band selective decoupling using the perfect echo principle. This modification allows a complete backbone decoupling (amide- and α-protons) in peptides and opens band selective homonuclear decoupling to substances with two mutually coupled protons in the spectral range of interest.
Collapse
Affiliation(s)
- Julian Ilgen
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
| | - Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
| |
Collapse
|
17
|
Nolis P, Parella T. Multiplicity-edited 1 H- 1 H TOCSY experiment. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:976-982. [PMID: 29220535 DOI: 10.1002/mrc.4695] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 10/27/2017] [Accepted: 11/28/2017] [Indexed: 06/07/2023]
Abstract
A 1 H-1 H total correlation spectroscopy (TOCSY) experiment incorporating 13 C multiplicity information is proposed. In addition, broadband 1 H homodecoupling in the indirect dimension can be implemented using a perfect BIRD module that affords exclusive 1 H chemical shift evolution with full decoupling of all heteronuclear and homonuclear (including 2 JHH ) coupling constants. As a complement to the normal TOCSY and the recent PSYCHE-TOCSY experiments, this novel multiplicity-edited TOCSY experiment distinguishes between CH/CH3 (phased up) and CH2 (phased down) cross-peaks, which facilitates resonance analysis and assignment.
Collapse
Affiliation(s)
- Pau Nolis
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Catalonia, Spain
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Catalonia, Spain
| |
Collapse
|
18
|
Aguilar JA, Kenwright AM. Compressed NMR: Combining compressive sampling and pure shift NMR techniques. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:983-992. [PMID: 29278289 DOI: 10.1002/mrc.4705] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 12/08/2017] [Accepted: 12/13/2017] [Indexed: 06/07/2023]
Abstract
Historically, the resolution of multidimensional nuclear magnetic resonance (NMR) has been orders of magnitude lower than the intrinsic resolution that NMR spectrometers are capable of producing. The slowness of Nyquist sampling as well as the existence of signals as multiplets instead of singlets have been two of the main reasons for this underperformance. Fortunately, two compressive techniques have appeared that can overcome these limitations. Compressive sensing, also known as compressed sampling (CS), avoids the first limitation by exploiting the compressibility of typical NMR spectra, thus allowing sampling at sub-Nyquist rates, and pure shift techniques eliminate the second issue "compressing" multiplets into singlets. This paper explores the possibilities and challenges presented by this combination (compressed NMR). First, a description of the CS framework is given, followed by a description of the importance of combining it with the right pure shift experiment. Second, examples of compressed NMR spectra and how they can be combined with covariance methods will be shown.
Collapse
|
19
|
Parella T. Current developments in homonuclear and heteronuclear J-resolved NMR experiments. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:230-250. [PMID: 29314247 DOI: 10.1002/mrc.4706] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 12/12/2017] [Accepted: 12/12/2017] [Indexed: 06/07/2023]
Abstract
Two-dimensional J-resolved (Jres) NMR experiments offer a simple, user-friendly spectral representation where the information of coupling constants and chemical shifts are separated into two orthogonal frequency axis. Since its initial proposal 40 years ago, Jres has been the focus of considerable interest both in improving the basic pulse sequence and in its successful application to a wide range of studies. Here, the latest developments in the design of novel Jres pulse schemes are reviewed, mainly focusing on obtaining pure absorption lineshapes, minimizing strong coupling artifacts, and also optimizing sensitivity and experimental measurements. A discussion of several Jres versions for the accurate measurement of a different number of homonuclear (JHH ) and heteronuclear (JCH ) coupling constants is presented, accompanied by some illustrative examples.
Collapse
Affiliation(s)
- Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Catalonia, Spain
| |
Collapse
|
20
|
Ilgen J, Kaltschnee L, Thiele CM. A pure shift experiment with increased sensitivity and superior performance for strongly coupled systems. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 286:18-29. [PMID: 29172170 DOI: 10.1016/j.jmr.2017.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 11/03/2017] [Accepted: 11/05/2017] [Indexed: 06/07/2023]
Abstract
Motivated by the persisting need for enhanced resolution in solution state NMR spectra, pure shift techniques such as Zangger-Sterk decoupling have recently attracted widespread interest. These techniques for homonuclear decoupling offer enhanced resolution in one- and multidimensional proton detected experiments by simplifying multiplet structures. In this work, a modification to the popular Zangger-Sterk technique PEPSIE (Perfect Echo Pure Shift Improved Experiment) is presented, which decouples pairs of spins even if they share the same volume element. This in turn can drastically improve the sensitivity, as compared to classical Zangger-Sterk decoupling, as larger volume elements can be used to collect the detected signal. Most interestingly, even in the presence of moderate strong coupling, the PEPSIE experiment produces clean and widely artifact free spectra. In order to better understand this - to us initially - surprising behaviour we performed analyses using numerical simulations and derived an (approximate) analytical solution from density matrix formalism. We show that this experiment is particularly suitable to study samples with strong signal clustering, a situation which can render classic Zangger-Sterk decoupling inefficient.
Collapse
Affiliation(s)
- Julian Ilgen
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany.
| |
Collapse
|
21
|
Verma A, Bhattacharya S, Baishya B. Perfecting band selective homo-decoupling for decoupling two signals coupled within the same band. RSC Adv 2018; 8:19990-19999. [PMID: 35541648 PMCID: PMC9080728 DOI: 10.1039/c8ra01272e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 05/19/2018] [Indexed: 11/21/2022] Open
Abstract
Recently, pure shift NMR methods have delivered ultrahigh resolution broadband proton NMR spectra that display singlet peak per chemical site. BASH/HOBS (band selective homo-decoupling/homonuclear band selective) decoupling is the only method that provides singlet only spectrum for a selected signal or a group of signals with a sensitivity higher than regular proton NMR, and an order of magnitude higher than broadband pure shift techniques. It is this aspect that makes this technique important. In the present work, we show that perfect echo (PE) when combined with band selective homo-decoupling (BASHD) permits increasing the bandwidth of the BASH/HOBS decoupling resulting in reduced experimental time for this class of experiments. Using new PE-BASHD technique two closely resonating coupled signals could be decoupled in a single experiment which otherwise demands two separate BASHD experiments. In polypeptides, it also allows decoupling of Hα and HN signals simultaneously from each other as well as from the side chain protons reducing experimental time. Further, pseudo 2D based PE-BASHD scheme provides spectrum superior to the real-time BASHD spectrum when applied to closely resonating coupled signals. Numerical simulation as well as experimental results indicate that the PE-BASHD sequence display good quality singlet only spectrum even in the presence of moderate strong coupling. Perfecting Echo Band Selective Homo-decoupling (PE-BASHD) reduces experimental time by performing simultaneous homo-decoupling of two closely resonating coupled signals.![]()
Collapse
Affiliation(s)
- Ajay Verma
- Centre of Biomedical Research
- Lucknow-226014
- India
- Department of Chemistry
- Institute of Science
| | - Subrato Bhattacharya
- Department of Chemistry
- Institute of Science
- Banaras Hindu University
- Banaras-221005
- India
| | | |
Collapse
|
22
|
Verma A, Parihar R, Bhattacharya S, Baishya B. Analyses of Complex Mixtures by F 1 Homo-Decoupled Diagonal Suppressed Total Correlation Spectroscopy. Chemphyschem 2017; 18:3076-3082. [PMID: 28833930 DOI: 10.1002/cphc.201700662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 07/31/2017] [Indexed: 11/07/2022]
Abstract
A diagonal suppressed F1 decoupled total correlation spectroscopy(TOCSY) experiment is developed for analyses of complex mixtures. In 2D homonuclear correlation, assignment of the cross peaks is crucial for structure elucidation. However, when cross peaks are close to the diagonal peaks in overcrowded spectral regions, their assignment becomes tedious. In complex mixtures, the presence of multiple spectra along with broad and complex proton multiplets owing to homonuclear scalar couplings degrade the resolution to the extent that assignment of various cross peaks becomes tedious or impossible. Herein, a diagonal suppressed total correlation technique with F1 decoupling is presented to improve the resolution of the cross peaks. The resolution of the cross peaks is improved by both diagonal suppression as well as the collapse of the multiplets to singlets. Application of the method to a few mixtures of organic compounds reveals better identification of the cross peaks relative to other TOCSY variants.
Collapse
Affiliation(s)
- Ajay Verma
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow, 226014, U. P., India.,Department of Chemistry, Institute of Science, Banaras Hindu University, Banaras, 221005, U. P., India
| | - Rashmi Parihar
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow, 226014, U. P., India.,Department of Bioinformatics, Dr. A. P. J. Abdul Kalam Technical University, Lucknow, 226021, U. P., India
| | - Subrato Bhattacharya
- Department of Chemistry, Institute of Science, Banaras Hindu University, Banaras, 221005, U. P., India
| | - Bikash Baishya
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow, 226014, U. P., India
| |
Collapse
|
23
|
Le Guennec A, Tayyari F, Edison AS. Alternatives to Nuclear Overhauser Enhancement Spectroscopy Presat and Carr-Purcell-Meiboom-Gill Presat for NMR-Based Metabolomics. Anal Chem 2017; 89:8582-8588. [PMID: 28737383 PMCID: PMC5588096 DOI: 10.1021/acs.analchem.7b02354] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 07/24/2017] [Indexed: 01/01/2023]
Abstract
NMR metabolomics are primarily conducted with 1D nuclear Overhauser enhancement spectroscopy (NOESY) presat for water suppression and Carr-Purcell-Meiboom-Gill (CPMG) presat as a T2 filter to remove macromolecule signals. Others pulse sequences exist for these two objectives but are not often used in metabolomics studies, because they are less robust or unknown to the NMR metabolomics community. However, recent improvements on alternative pulse sequences provide attractive alternatives to 1D NOESY presat and CPMG presat. We focus this perspective on PURGE, a water suppression technique, and PROJECT presat, a T2 filter. These two pulse sequences, when optimized, performed at least on par with 1D NOESY presat and CPMG presat, if not better. These pulse sequences were tested on common samples for metabolomics, human plasma, and urine.
Collapse
Affiliation(s)
- Adrien Le Guennec
- Complex
Carbohydrate Research Center (CCRC), Departments of Genetics and Biochemistry
& Molecular Biology, and Institute of Bioinformatics, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United
States
| | - Fariba Tayyari
- Complex
Carbohydrate Research Center (CCRC), Departments of Genetics and Biochemistry
& Molecular Biology, and Institute of Bioinformatics, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United
States
| | - Arthur S. Edison
- Complex
Carbohydrate Research Center (CCRC), Departments of Genetics and Biochemistry
& Molecular Biology, and Institute of Bioinformatics, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United
States
| |
Collapse
|
24
|
Schulze-Sünninghausen D, Becker J, Koos MRM, Luy B. Improvements, extensions, and practical aspects of rapid ASAP-HSQC and ALSOFAST-HSQC pulse sequences for studying small molecules at natural abundance. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 281:151-161. [PMID: 28603039 DOI: 10.1016/j.jmr.2017.05.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/17/2017] [Accepted: 05/22/2017] [Indexed: 06/07/2023]
Abstract
Previously we introduced two novel NMR experiments for small molecules, the so-called ASAP-HSQC and ALSOFAST-HSQC (Schulze-Sünninghausen et al., 2014), which allow the detection of heteronuclear one-bond correlations in less than 30s at natural abundance. We propose an improved symmetrized pulse scheme of the basic experiment to minimize artifact intensities and the combination with non-uniform sampling to enable the acquisition of conventional HSQC spectra in as short as a couple of seconds and extremely 13C-resolved spectra in less than ten minutes. Based on steady state investigations, a first estimate to relative achievable signal intensities with respect to conventional, ASAP-, and ALSOFAST-HSQC experiments is given. In addition, we describe several extensions to the basic pulse schemes, like a multiplicity-edited version, a revised symmetrized CLIP-ASAP-HSQC, an ASAP-/ALSOFAST-HSQC sequence with broadband BIRD-based 1H,1H decoupling, and a symmetrized sequence optimized for water suppression. Finally, RF-power considerations with respect to the high duty cycle of the experiments are given.
Collapse
Affiliation(s)
- David Schulze-Sünninghausen
- Institute of Organic Chemistry and Institute for Biological Interfaces 4 - Magnetic Resonance, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany; Bruker BioSpin GmbH, Rudolf-Plank-Str. 23, 76275 Ettlingen, Germany
| | - Johanna Becker
- Institute of Organic Chemistry and Institute for Biological Interfaces 4 - Magnetic Resonance, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Martin R M Koos
- Institute of Organic Chemistry and Institute for Biological Interfaces 4 - Magnetic Resonance, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Burkhard Luy
- Institute of Organic Chemistry and Institute for Biological Interfaces 4 - Magnetic Resonance, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
| |
Collapse
|
25
|
Nath N, Verma A, Baishya B, Khetrapal CL. Real time band selective F 1 -decoupled proton NMR for the demixing of overlay spectra of chiral molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:553-558. [PMID: 27813168 DOI: 10.1002/mrc.4547] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 10/27/2016] [Accepted: 10/30/2016] [Indexed: 06/06/2023]
Abstract
The small chemical shift dispersion and complex multiplicity pattern in proton NMR limit quantifications, for instance the determination of enantiomeric excess (ee) for an enantiomeric mixture. Herein, we present a simple proton-proton correlation experiment with band selective homonuclear (BASH) decoupling in both F1 and F2 dimensions, for the removal of scalar and residual dipolar couplings to provide collapsed singlet for each chemical site. The method has been demonstrated to separate the severely overlapped spectra of enantiomers using both chiral isotropic and anisotropic phases as well as a small biomolecule, particularly for the diastereotopic protons and also for the determination of ee. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Nilamoni Nath
- Department of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Goettingen, Germany
| | - Ajay Verma
- Centre of Biomedical Research, SGPGIMS Campus, Lucknow, U. P., India
| | - Bikash Baishya
- Centre of Biomedical Research, SGPGIMS Campus, Lucknow, U. P., India
| | | |
Collapse
|
26
|
Marcó N, Gil RR, Parella T. Structural discrimination from in situ measurement of 1 D CH and 2 D HH residual dipolar coupling constants. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:540-545. [PMID: 28043096 DOI: 10.1002/mrc.4575] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 12/23/2016] [Accepted: 12/29/2016] [Indexed: 06/06/2023]
Abstract
A fast residual dipolar coupling constant-assisted strategy involving the simultaneous determination of scalar and total coupling constants from a single 1 JCH /2 JHH -resolved NMR spectrum is reported. It is shown that the concerted use of the directly measured 1 DCH (for all CHn multiplicities) and 2 DHH residual dipolar couplings allows an on-the-fly assignment of diastereotopic CH2 protons, as well as of an efficient discrimination between diastereoisomeric structures of strychnine which contains six stereocenters. Copyright © 2017 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Núria Marcó
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Ave, Pittsburgh, PA, 15213, USA
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| |
Collapse
|
27
|
Marcó N, Souza AA, Nolis P, Gil RR, Parella T. Perfect 1J CH-resolved HSQC: Efficient measurement of one-bond proton-carbon coupling constants along the indirect dimension. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 276:37-42. [PMID: 28092787 DOI: 10.1016/j.jmr.2017.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 12/30/2016] [Accepted: 01/01/2017] [Indexed: 06/06/2023]
Abstract
A versatile 1JCH-resolved HSQC pulse scheme for the speedy, accurate and automated determination of one-bond proton-carbon coupling constants is reported. The implementation of a perfectBIRD element allows a straightforward measurement from the clean doublets obtained along the highly resolved F1 dimension, even for each individual 1JCHa and 1JCHb in diastereotopic HaCHb methylene groups. Real-time homodecoupling during acquisition and other alternatives to minimize accidental signal overlapping in overcrowded spectra are also discussed.
Collapse
Affiliation(s)
- N Marcó
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| | - A A Souza
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain; Departamento de Química, Universidade Federal do Piauí, 64049-550 Teresina, PI, Brazil
| | - P Nolis
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| | - R R Gil
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, USA
| | - T Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain.
| |
Collapse
|
28
|
Marcó N, Souza AA, Nolis P, Cobas C, Gil RR, Parella T. 1JCH NMR Profile: Identification of Key Structural Features and Functionalities by Visual Observation and Direct Measurement of One-Bond Proton-Carbon Coupling Constants. J Org Chem 2017; 82:2040-2044. [DOI: 10.1021/acs.joc.6b02873] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Núria Marcó
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) Catalonia, Spain
| | - Alexandre A. Souza
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) Catalonia, Spain
- Departamento
de Química, Universidade Federal do Piauí, Teresina, PI 64049-550, Brazil
| | - Pau Nolis
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) Catalonia, Spain
| | - Carlos Cobas
- Mestrelab Research, Santiago de Compostela, E-15706 A Coruña, Spain
| | - Roberto R. Gil
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Teodor Parella
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona) Catalonia, Spain
| |
Collapse
|
29
|
Castañar L. Pure shift 1 H NMR: what is next? MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:47-53. [PMID: 27761957 DOI: 10.1002/mrc.4545] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 10/14/2016] [Accepted: 10/17/2016] [Indexed: 06/06/2023]
Abstract
Currently, pure shift nuclear magnetic resonance (NMR) is an area of high interest. The aim of this contribution is to describe briefly how this technique has evolved, where it is now and what could be the next challenges in the amazing adventure of the development and application of pure shift NMR experiments. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Laura Castañar
- School of Chemistry, University of Manchester, Manchester, UK
| |
Collapse
|
30
|
Schmidts V. Perspectives in the application of residual dipolar couplings in the structure elucidation of weakly aligned small molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:54-60. [PMID: 27743456 DOI: 10.1002/mrc.4543] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 05/28/2023]
Abstract
This perspective article aims to review the general methodology in the application of residual dipolar couplings (RDCs) in the structure elucidation of small molecules and give the author's view on challenges for future applications. Recent improvements in the availability of alignment media, new pulse sequences for the measurement of couplings and improvements in the analysis software have garnered widespread interest in the technique. However, further generalization is needed in order to make RDC analysis into a truly "routine" method. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
| |
Collapse
|
31
|
Kakita VMR, Hosur RV. Hadamard Homonuclear Broadband Decoupled TOCSY NMR: Improved Efficacy in Detecting Long-range Chemical Shift Correlations. Chemphyschem 2016; 17:4037-4042. [DOI: 10.1002/cphc.201600769] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/30/2016] [Indexed: 12/28/2022]
Affiliation(s)
- Veera Mohana Rao Kakita
- UM-DAE-Centre for Excellence in Basic Sciences; University of Mumbai; Kalina Campus, Santa Cruz Mumbai 400 098 India
| | - Ramakrishna V. Hosur
- UM-DAE-Centre for Excellence in Basic Sciences; University of Mumbai; Kalina Campus, Santa Cruz Mumbai 400 098 India
- Department of Chemical Sciences; Tata Institute of Fundamental Research (TIFR); 1-Homi Bhabha Road, Colaba Mumbai 400 005 India
| |
Collapse
|
32
|
Castañar L, Garcia M, Hellemann E, Nolis P, Gil RR, Parella T. One-Shot Determination of Residual Dipolar Couplings: Application to the Structural Discrimination of Small Molecules Containing Multiple Stereocenters. J Org Chem 2016; 81:11126-11131. [DOI: 10.1021/acs.joc.6b02103] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laura Castañar
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| | - Manuela Garcia
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Erich Hellemann
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Pau Nolis
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| | - Roberto R. Gil
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Teodor Parella
- Servei
de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain
| |
Collapse
|
33
|
Kaltschnee L, Knoll K, Schmidts V, Adams RW, Nilsson M, Morris GA, Thiele CM. Extraction of distance restraints from pure shift NOE experiments. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 271:99-109. [PMID: 27591956 DOI: 10.1016/j.jmr.2016.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/15/2016] [Accepted: 08/16/2016] [Indexed: 06/06/2023]
Abstract
NMR techniques incorporating pure shift methods to improve signal resolution have recently attracted much attention, owing to their potential use in studies of increasingly complex molecular systems. Extraction of frequencies from these simplified spectra enables easier structure determination, but only a few of the methods presented provide structural parameters derived from signal integral measurements. In particular, for quantification of the nuclear Overhauser effect (NOE) it is highly desirable to utilize pure shift techniques where signal overlap normally prevents accurate signal integration, to enable measurement of a larger number of interatomic distances. However, robust methods for the measurement of interatomic distances using the recently developed pure shift techniques have not been reported to date. In this work we discuss some of the factors determining the accuracy of measurements of signal integrals in interferogram-based Zangger-Sterk (ZS) pure shift NMR experiments. The ZS broadband homodecoupling technique is used in different experiments designed for quantitative NOE determination from pure shift spectra. It is shown that the techniques studied can be used for quantitative extraction of NOE-derived distance restraints, as exemplified for the test case of strychnine.
Collapse
Affiliation(s)
- Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Kevin Knoll
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Ralph W Adams
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Mathias Nilsson
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Gareth A Morris
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany.
| |
Collapse
|
34
|
Koos MRM, Kummerlöwe G, Kaltschnee L, Thiele CM, Luy B. CLIP-COSY: A Clean In-Phase Experiment for the Rapid Acquisition of COSY-type Correlations. Angew Chem Int Ed Engl 2016; 55:7655-9. [DOI: 10.1002/anie.201510938] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 02/05/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Martin R. M. Koos
- Institut für Organische Chemie and Institut für Biologische, Grenzflächen 4-Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Grit Kummerlöwe
- Institut für Organische Chemie; Technische Universität München; Lichtenbergstrasse 4 85747 Garching Germany
| | - Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie; Technische Universität Darmstadt; Alarich-Weiss-Strasse 16 64287 Darmstadt Germany
| | - Christina M. Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie; Technische Universität Darmstadt; Alarich-Weiss-Strasse 16 64287 Darmstadt Germany
| | - Burkhard Luy
- Institut für Organische Chemie and Institut für Biologische, Grenzflächen 4-Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| |
Collapse
|
35
|
Koos MRM, Kummerlöwe G, Kaltschnee L, Thiele CM, Luy B. CLIP-COSY: Reine Inphase-Signale und schnelle Akquisition COSY-artiger Korrelationen. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201510938] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Martin R. M. Koos
- Institut für Organische Chemie und Institut für Biologische, Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Deutschland
| | - Grit Kummerlöwe
- Institut für Organische Chemie; Technische Universität München; Lichtenbergstraße 4 85747 Garching Deutschland
| | - Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie; Technische Universität Darmstadt; Alarich-Weiss-Straße 16 64287 Darmstadt Deutschland
| | - Christina M. Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie; Technische Universität Darmstadt; Alarich-Weiss-Straße 16 64287 Darmstadt Deutschland
| | - Burkhard Luy
- Institut für Organische Chemie und Institut für Biologische, Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Deutschland
| |
Collapse
|
36
|
Kakita VMR, Hosur RV. Non-Uniform-Sampling Ultrahigh Resolution TOCSY NMR: Analysis of Complex Mixtures at Microgram Levels. Chemphyschem 2016; 17:2304-8. [DOI: 10.1002/cphc.201600255] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Indexed: 12/27/2022]
Affiliation(s)
- Veera M. R. Kakita
- UM-DAE Centre for Excellence in Basic Sciences; Mumbai University Campus, Kalina, Santa Cruz Mumbai 400 098 India
| | - Ramakrishna V. Hosur
- UM-DAE Centre for Excellence in Basic Sciences; Mumbai University Campus, Kalina, Santa Cruz Mumbai 400 098 India
- Department of Chemical Sciences; Tata Institute of Fundamental Research (TIFR); 1-Homi Bhabha Road, Colaba Mumbai 400 005 India
| |
Collapse
|
37
|
Fredi A, Nolis P, Cobas C, Martin GE, Parella T. Exploring the use of Generalized Indirect Covariance to reconstruct pure shift NMR spectra: Current Pros and Cons. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 266:16-22. [PMID: 27003379 DOI: 10.1016/j.jmr.2016.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/05/2016] [Accepted: 03/07/2016] [Indexed: 06/05/2023]
Abstract
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 spectrum is described. Reconstructed pure shift NMR spectra of NOESY, HSQC, HSQC-TOCSY and HSQMBC experiments are reported for the target molecule strychnine.
Collapse
Affiliation(s)
- André Fredi
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Catalonia, Spain
| | - Pau Nolis
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Catalonia, Spain
| | - Carlos Cobas
- Mestrelab Research, Santiago de Compostela, E-15706 A Coruña, Spain
| | - Gary E Martin
- NMR Structure Elucidation, Process & Analytical Chemistry, Merck & Co. Inc., 126 E. Lincoln Avenue, Rahway, NJ 07065, United States
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Catalonia, Spain.
| |
Collapse
|
38
|
Verma A, Baishya B. Real-time bilinear rotation decoupling in absorptive mode J-spectroscopy: Detecting low-intensity metabolite peak close to high-intensity metabolite peak with convenience. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 266:51-58. [PMID: 27026651 DOI: 10.1016/j.jmr.2016.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 03/02/2016] [Accepted: 03/05/2016] [Indexed: 06/05/2023]
Abstract
"Pure shift" NMR spectra display singlet peak per chemical site. Thus, high resolution is offered at the cost of valuable J-coupling information. In the present work, real-time BIRD (BIlinear Rotation Decoupling) is applied to the absorptive-mode 2D J-spectroscopy to provide pure shift spectrum in the direct dimension and J-coupling information in the indirect dimension. Quite often in metabolomics, proton NMR spectra from complex bio-fluids display tremendous signal overlap. Although conventional J-spectroscopy in principle overcomes this problem by separating the multiplet information from chemical shift information, however, only magnitude mode of the experiment is practical, sacrificing much of the potential high resolution that could be achieved. Few J-spectroscopy methods have been reported so far that produce high-resolution pure shift spectrum along with J-coupling information for crowded spectral regions. In the present work, high-quality J-resolved spectrum from important metabolomic mixture such as tissue extract from rat cortex is demonstrated. Many low-intensity metabolite peaks which are obscured by the broad dispersive tails from high-intensity metabolite peaks in regular magnitude mode J-spectrum can be clearly identified in real-time BIRD J-resolved spectrum. The general practice of removing such spectral overlap is tedious and time-consuming as it involves repeated sample preparation to change the pH of the tissue extract sample and subsequent spectra recording.
Collapse
Affiliation(s)
- Ajay Verma
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India
| | - Bikash Baishya
- Centre of Biomedical Research (Formerly Centre of Biomedical Magnetic Resonance), SGPGIMS Campus, Raebareli Road, Lucknow 226014, India.
| |
Collapse
|
39
|
Mauve C, Khlifi S, Gilard F, Mouille G, Farjon J. Sensitive, highly resolved, and quantitative (1)H-(13)C NMR data in one go for tracking metabolites in vegetal extracts. Chem Commun (Camb) 2016; 52:6142-5. [PMID: 27074265 DOI: 10.1039/c6cc01783e] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The quantification of metabolites is essential for understanding and improving biological systems. With the aim to quantify in one map a complex mixture composed of low concentrated metabolites, a new experiment called the (1)H-(13)C QUIPU HSQC allows improving of both resolution and sensitivity for investigation of vegetal extracts.
Collapse
Affiliation(s)
- Caroline Mauve
- Plateforme Métabolisme-Métabolome, Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Paris Diderot, Sorbonne Paris-Cité, bât 630, 91405 Orsay, France
| | | | | | | | | |
Collapse
|
40
|
Kakita VMR, Vemulapalli SPB, Bharatam J. Band-selective excited ultrahigh resolution PSYCHE-TOCSY: fast screening of organic molecules and complex mixtures. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2016; 54:308-314. [PMID: 26939986 DOI: 10.1002/mrc.4376] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 08/27/2015] [Accepted: 09/29/2015] [Indexed: 06/05/2023]
Abstract
Precise assignments of (1) H atomic sites and establishment of their through-bond COSY or TOCSY connectivity are crucial for molecular structural characterization by using (1) H NMR spectroscopy. However, this exercise is often hampered by signal overlap, primarily because of (1) H-(1) H scalar coupling multiplets, even at typical high magnetic fields. The recent developments in homodecoupling strategies for effectively suppressing the coupling multiplets into nice singlets (pure-shift), particularly, Morris's advanced broadband pure-shift yielded by chirp excitation (PSYCHE) decoupling and ultrahigh resolution PSYCHE-TOCSY schemes, have shown new possibilities for unambiguous structural elucidation of complex organic molecules. The superior broadband PSYCHE-TOCSY exhibits enhanced performance over the earlier TOCSY methods, which however warrants prolonged experimental times due to the requirement of large number of dwell increments along the indirect dimension. Herein, we present fast and band-selective analog of the broadband PSYCHE-TOCSY, which is useful for analyzing complex organic molecules that exhibit characteristic yet crowded spectral regions. The simple pulse scheme relies on band-selective excitation (BSE) followed by PSYCHE homodecoupling in the indirect dimension. The BSE-PSYCHE-TOCSY has been exemplified for Estradiol and a complex carbohydrate mixture comprised of six constituents of closely comparable molecular weights. The experimental times are greatly reduced viz., ~20 fold for Estradiol and ~10 fold for carbohydrate mixture, with respect to the broadband PSYCHE-TOCSY. Furthermore, unlike the earlier homonuclear band-selective decoupling, the BSE-PSYCHE-decoupling provides fully decoupled pure-shift spectra for all the individual chemical sites within the excited band. The BSE-PSYCHE-TOCSY is expected to have significant potential for quick screening of complex organic molecules and mixtures at ultrahigh resolution. Copyright © 2015 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Veera Mohana Rao Kakita
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500 007, India
| | - Sahithya Phani Babu Vemulapalli
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500 007, India
- Academy of Scientific and Innovative Research (AcSIR), Hyderabad, 500 007, India
| | - Jagadeesh Bharatam
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500 007, India
- Academy of Scientific and Innovative Research (AcSIR), Hyderabad, 500 007, India
| |
Collapse
|
41
|
Rao Kakita VM, Shukla VK, Bopardikar M, Bhattacharya T, Hosur R. Measurement of 1H NMR relaxation times in complex organic chemical systems: application of PSYCHE. RSC Adv 2016. [DOI: 10.1039/c6ra20047h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In complex organic molecules, relaxation times measured from the PSYCHE homonuclear broadband decoupling methods provide a wealth of information on intramolecular dynamics and intermolecular interactions.
Collapse
Affiliation(s)
| | - Vaibhav Kumar Shukla
- UM-DAE Centre for Excellence in Basic Sciences
- University of Mumbai
- Mumbai 400 098
- India
| | - Mandar Bopardikar
- Department of Chemical Sciences
- Tata Institute of Fundamental Research (TIFR)
- Mumbai 400 005
- India
| | | | - Ramakrishna V. Hosur
- UM-DAE Centre for Excellence in Basic Sciences
- University of Mumbai
- Mumbai 400 098
- India
- Department of Chemical Sciences
| |
Collapse
|
42
|
Timári I, Kaltschnee L, Raics MH, Roth F, Bell NGA, Adams RW, Nilsson M, Uhrín D, Morris GA, Thiele CM, Kövér KE. Real-time broadband proton-homodecoupled CLIP/CLAP-HSQC for automated measurement of heteronuclear one-bond coupling constants. RSC Adv 2016. [DOI: 10.1039/c6ra14329f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A new method is proposed that allows broadband homonuclear decoupled CLIP/CLAP-HSQC NMR spectra to be acquired at virtually no extra cost in measurement time.
Collapse
Affiliation(s)
- István Timári
- Department of Inorganic and Analytical Chemistry
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- D-64287 Darmstadt
- Germany
| | - Mária H. Raics
- Department of Inorganic and Analytical Chemistry
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - Felix Roth
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- D-64287 Darmstadt
- Germany
| | | | | | | | - Dušan Uhrín
- EastCHEM School of Chemistry
- University of Edinburgh
- Edinburgh
- UK
| | | | - Christina M. Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- D-64287 Darmstadt
- Germany
| | - Katalin E. Kövér
- Department of Inorganic and Analytical Chemistry
- University of Debrecen
- H-4032 Debrecen
- Hungary
| |
Collapse
|
43
|
Mauhart J, Glanzer S, Sakhaii P, Bermel W, Zangger K. Faster and cleaner real-time pure shift NMR experiments. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 259:207-15. [PMID: 26363584 DOI: 10.1016/j.jmr.2015.08.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 08/12/2015] [Accepted: 08/22/2015] [Indexed: 06/05/2023]
Abstract
Real-time pure shift experiments provide highly resolved proton NMR spectra which do not require any special processing. Although being more sensitive than their pseudo 2D counterparts, their signal intensities per unit time are still far below regular NMR spectra. In addition, scalar coupling evolution during the individual data chunks produces decoupling sidebands. Here we show that faster and cleaner real-time pure shift spectra can be obtained through the implementation of two parameter alterations. Variation of the FID chunk lengths between individual transients significantly suppresses decoupling sidebands for any kind of real-time pure shift spectra and thus allows for example the analysis of minor components in compound mixtures. Shifting the excitation frequency between individual scans of real-time slice-selective pure shift spectra increases their sensitivity obtainable in unit time by allowing faster repetitions of acquisitions.
Collapse
Affiliation(s)
- Johannes Mauhart
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Austria.
| | - Simon Glanzer
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Austria.
| | - Peyman Sakhaii
- NMR Laboratory of SANOFI, C&BD (Chemistry & Biotechnology Development Frankfurt Chemistry), Industriepark Hoechst, Building G849, D-65926 Frankfurt/Main, Germany.
| | | | - Klaus Zangger
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Austria.
| |
Collapse
|
44
|
Rachineni K, Kakita VMR, Dayaka S, Vemulapalli SPB, Bharatam J. Precise Determination of Enantiomeric Excess by a Sensitivity Enhanced Two-Dimensional Band-Selective Pure-Shift NMR. Anal Chem 2015; 87:7258-66. [PMID: 26091767 DOI: 10.1021/acs.analchem.5b01288] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Unambiguous identification and precise quantification of enantiomers in chiral mixtures is crucial for enantiomer specific synthesis as well as chemical analysis. The task is often challenging for mixtures with high enantiomeric excess and for complex molecules with strong (1)H-(1)H scalar (J) coupling network. The recent advancements in (1)H-(1)H decoupling strategies to suppress the J-interactions offered new possibilities for NMR based unambiguous discrimination and quantification enantiomers. Herein, we discuss a high resolution two-dimensional pure-shift zCOSY NMR method with homonuclear band-selective decoupling in both the F1 and F2 dimensions (F1F2-HOBS-zCOSY). This advanced method shows a sharp improvement in resolution over the other COSY methods and also eliminates the problems associated with the overlapping decoupling sidebands. The efficacy of this method has been exploited for precise quantification of enantiomeric excess (ee) ratio (R/S) up to 99:1 in the presence of very low concentrations of chiral lanthanide shift reagents (CLSR) or chiral solvating agents (CSA). The F1F2-HOBS-zCOSY is simple and can be easily implemented on any modern NMR spectrometers, as a routine analytical tool.
Collapse
Affiliation(s)
- Kavitha Rachineni
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad-500 007, Telangana, India
| | - Veera Mohana Rao Kakita
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad-500 007, Telangana, India
| | - Satyanarayana Dayaka
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad-500 007, Telangana, India
| | - Sahithya Phani Babu Vemulapalli
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad-500 007, Telangana, India
| | - Jagadeesh Bharatam
- Centre for NMR and Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad-500 007, Telangana, India
| |
Collapse
|
45
|
Castañar L, Parella T. Broadband 1H homodecoupled NMR experiments: recent developments, methods and applications. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:399-426. [PMID: 25899911 DOI: 10.1002/mrc.4238] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 02/23/2015] [Accepted: 02/25/2015] [Indexed: 06/04/2023]
Abstract
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. A detailed discussion about the most relevant practical aspects in terms of pulse sequence design, selectivity, sensitivity, spectral resolution and performance is provided. Finally, the implementation of the different reported strategies into traditional 1D and 2D NMR experiments is described while several practical applications are also reviewed.
Collapse
Affiliation(s)
- Laura Castañar
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Catalonia, Spain
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear and Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Catalonia, Spain
| |
Collapse
|
46
|
Zangger K. Pure shift NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 86-87:1-20. [PMID: 25919196 DOI: 10.1016/j.pnmrs.2015.02.002] [Citation(s) in RCA: 234] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Revised: 02/04/2015] [Accepted: 02/05/2015] [Indexed: 05/08/2023]
Abstract
Although scalar-coupling provides important structural information, the resulting signal splittings significantly reduce the resolution of NMR spectra. Limited resolution is a particular problem in proton NMR experiments, resulting in part from the limited proton chemical shift range (∼10 ppm) but even more from the splittings due to scalar coupling to nearby protons. "Pure shift" NMR spectroscopy (also known as broadband homonuclear decoupling) has been developed for disentangling overlapped proton NMR spectra. The resulting spectra are considerably simplified as they consist of single lines, reminiscent of proton-decoupled C-13 spectra at natural abundance, with no multiplet structure. The different approaches to obtaining pure shift spectra are reviewed here and several applications presented. Pure shift spectra are especially useful for highly overlapped proton spectra, as found for example in reaction mixtures, natural products and biomacromolecules.
Collapse
Affiliation(s)
- Klaus Zangger
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria.
| |
Collapse
|
47
|
Aguilar JA, Cassani J, Delbianco M, Adams RW, Nilsson M, Morris GA. Minimising Research Bottlenecks by Decluttering NMR Spectra. Chemistry 2015; 21:6623-30. [DOI: 10.1002/chem.201406283] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 01/27/2015] [Indexed: 11/11/2022]
|