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Tassoti S, Novak P, Butts CP, Zangger K. High Resolution for Chemical Shifts and Scalar Coupling Constants: The 2D Real-Time J-Upscaled PSYCHE-DIAG. Chemphyschem 2018; 19:3166-3170. [PMID: 30239094 DOI: 10.1002/cphc.201800746] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Indexed: 11/09/2022]
Abstract
The facile determination of chemical shift and scalar coupling constants in NMR spectra is often prevented by spectral overlap and limited resolution. Here, we present a high-resolution NMR experiment for the simultaneous detection of both resonance frequencies and coupling patterns even with small J-values. A PSYCHE-decoupled DIAG (Pure Shift Yielded by Chirp Excitation- DIAGonal) experiment, which resolves chemical shift in the indirect dimension of a 2D experiment is combined with real-time J-upscaling in order to visualize small coupling constants that would otherwise be hidden in the linewidth of a regular proton or DIAG spectrum.
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Affiliation(s)
- Sebastian Tassoti
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Heinrichstraße 28, A-8010, Graz, Austria
| | - Predrag Novak
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102 A, HR-10 000, Zagreb, Croatia
| | - Craig P Butts
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, United Kingdom
| | - Klaus Zangger
- Institute of Chemistry/Organic and Bioorganic Chemistry, University of Graz, Heinrichstraße 28, A-8010, Graz, Austria
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2
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Kakita VMR, Hosur RV. Real-time J-upscaling in two-dimensional pure shift diagonal NMR: Simultaneous resolution enhancement in chemical shifts and scalar couplings. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 296:176-180. [PMID: 30286413 DOI: 10.1016/j.jmr.2018.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 09/24/2018] [Accepted: 09/25/2018] [Indexed: 06/08/2023]
Abstract
A two-dimensional real-time J-upscaled pure shift diagonal pulse scheme, JS-PSYCHE-DIAG has been developed. This method enhances the resolution in scalar coupling multiplets by real-time J-upscaling during the direct acquisition, and these J-upscaled multiplets resolve on the diagonal at the respective pure shift positions, which results in resolution enhancement in chemical shifts. Thus, both chemical shifts and scalar couplings get better resolved simultaneously in the same NMR experiment. The efficacy of the present method has been demonstrated, (i) on hesperidin for resolving the J-upscaled multiplets belonging to diastereomers and (ii) on a natural product, strychnine, to measure small scalar couplings including the long range values.
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Affiliation(s)
- Veera Mohana Rao Kakita
- UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Santacruz, Mumbai 400 098, India
| | - Ramakrishna V Hosur
- UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Santacruz, Mumbai 400 098, India.
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Stewart NJ, Kumeta H, Tomohiro M, Hashimoto T, Hatae N, Matsumoto S. Long-range heteronuclear J-coupling constants in esters: Implications for 13C metabolic MRI by side-arm parahydrogen-induced polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 296:85-92. [PMID: 30223155 DOI: 10.1016/j.jmr.2018.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/28/2018] [Accepted: 08/28/2018] [Indexed: 06/08/2023]
Abstract
Side-arm parahydrogen induced polarization (PHIP-SAH) presents a cost-effective method for hyperpolarization of 13C metabolites (e.g. acetate, pyruvate) for metabolic MRI. The timing and efficiency of typical spin order transfer methods including magnetic field cycling and tailored RF pulse sequences crucially depends on the heteronuclear J coupling network between nascent parahydrogen protons and 13C, post-parahydrogenation of the target compound. In this work, heteronuclear nJHC (1 < n ≤ 5) couplings of acetate and pyruvate esters pertinent for PHIP-SAH were investigated experimentally using selective HSQMBC-based pulse sequences and numerically using DFT simulations. The CLIP-HSQMBC technique was used to quantify 2/3-bond JHC couplings, and 4/5-bond JHC ≲ 0.5 Hz were estimated by the sel-HSQMBC-TOCSY approach. Experimental and numerical (DFT-simulated) nJHC couplings were strongly correlated (P < 0.001). Implications for 13C hyperpolarization by magnetic field cycling, and PH-INEPT and ESOTHERIC type spin order transfer methods for PHIP-SAH were assessed, and the influence of direct nascent parahydrogen proton to 13C coupling when compared with indirect homonuclear TOCSY-type transfer through intermediate (non-nascent parahydrogen) protons was studied by the density matrix approach.
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Affiliation(s)
- Neil J Stewart
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan
| | - Hiroyuki Kumeta
- Department of Structural Biology, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan; Global Station for Soft Matter, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo, Japan
| | - Mitsushi Tomohiro
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan
| | - Takuya Hashimoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan; Department of Chemistry, Graduate School of Science, Chiba University, Chiba, Japan
| | - Noriyuki Hatae
- School of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Japan
| | - Shingo Matsumoto
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan; JST, PREST, Saitama, Japan.
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Buchberger K, Walenta M, Zangger K. Extracting unresolved coupling constants from complex multiplets by a real-time J-upscaled SERF experiment. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:934-940. [PMID: 29240255 PMCID: PMC6175170 DOI: 10.1002/mrc.4699] [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: 08/31/2017] [Revised: 11/30/2017] [Accepted: 12/04/2017] [Indexed: 05/08/2023]
Abstract
The measurement of small homonuclear coupling constants is often prevented by either their small size and/or overlap with other signal splittings. Here, we present a real-time method to extract such couplings without interference from other splittings, with a resolution that is beyond conventional NMR spectra. In this real-time J-upscaled SERF experiment, homonuclear coupling is removed by slice-selective pure shift NMR, whereas scalar coupling to only one selected signal is reintroduced by selective refocusing. The remaining couplings are enhanced by real-time J-upscaling during interruptions of the FID data acquisition. The resulting spectrum is not only simplified by the restriction of the scalar coupling but also its resolution enhanced. This improved resolution results from a reduction of signal broadening due to magnetic field inhomogeneities from 2 different sources: slice-selective excitation and the spin-echo type J-upscaling element.
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Affiliation(s)
- Kathrin Buchberger
- Institute of Chemistry/Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28A‐8010GrazAustria
| | - Martin Walenta
- Institute of Chemistry/Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28A‐8010GrazAustria
| | - Klaus Zangger
- Institute of Chemistry/Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28A‐8010GrazAustria
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Bigler P, Furrer J. Measurement of long-range heteronuclear coupling constants using the peak intensity in classical 1D HMBC spectra. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:329-337. [PMID: 29336081 DOI: 10.1002/mrc.4713] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 06/07/2023]
Abstract
In this contribution, we show that the magnitude of heteronuclear long-range coupling constants can be directly extracted from the classical 1D HMBC spectra, as all multiplet lines of a cross-peak always and exclusively vanish for the condition Δ = k/n JCH . To the best of our knowledge, this feature of the classical HMBC has not yet been noticed and exploited. This condition holds true, irrespective of the magnitude and numbers of additional active and passive homonuclear n JHH' couplings. Alternatively, the n JCH value may also be evaluated by fitting the peak's intensity in the individual spectra to its simple sin(πn JCH Δ)exp(-Δ/T2eff ) dependence. Compared to the previously proposed J-HMBC sequences that also use the variation of the cross-peak's intensity for extracting the coupling constants, the classical HMBC pulse sequence is significantly more sensitive.
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Affiliation(s)
- Peter Bigler
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, Berne, CH-3012, Switzerland
| | - Julien Furrer
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, Berne, CH-3012, Switzerland
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Koskela H, Kilpeläinen I, Heikkinen S. ME-CAGEBIRD r,X-CPMG-HSQMBC. A phase sensitive, multiplicity edited long range HSQC with absorptive line shapes. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 272:114-122. [PMID: 27689530 DOI: 10.1016/j.jmr.2016.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/15/2016] [Accepted: 09/15/2016] [Indexed: 06/06/2023]
Abstract
ME-CAGEBIRDr,X-CPMG-HSMBC pulse sequence is a phase sensitive, carbon multiplicity edited 2D-experiment for detecting heteronuclear correlations originating from long-range 1H, 13C-couplings, nJCH. The presented method allows measurement of nJCH-values as well as is capable of separating different carbon types in subspectra (13C/13CH2 and 13CH/13CH3) with minimal amount of cross talk i.e. cross peaks from wrong carbon multiplicity. Pure lineshapes and clean subspectra are achieved by utilizing CPMG in polarization transfer period, CRISIS-approach in multiplicity editing period and zero-quantum filtration. The obtained spectral properties together with simple setup of the experiment make ME-CAGEBIRDr,X-CPMG-HSMBC a useful addition into synthetic organic chemistry oriented NMR-tool collection.
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Affiliation(s)
- Harri Koskela
- VERIFIN, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki, Finland
| | - Ilkka Kilpeläinen
- Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki, Finland
| | - Sami Heikkinen
- Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki, Finland.
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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.
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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
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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.
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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
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