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Tichotová M, Landovský T, Lang J, Jeziorowski S, Schmidts V, Kohout M, Babor M, Lhoták P, Thiele CM, Dvořáková H. Enantiodiscrimination of Inherently Chiral Thiacalixarenes by Residual Dipolar Couplings. J Org Chem 2024; 89:9711-9720. [PMID: 36655948 PMCID: PMC11267606 DOI: 10.1021/acs.joc.2c02594] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Indexed: 01/20/2023]
Abstract
Inherently chiral compounds, such as calixarenes, are chiral due to a nonplanar three-dimensional (3D) structure. Determining their conformation is essential to understand their properties, with nuclear magnetic resonance (NMR) spectroscopy being one applicable method. Using alignment media to measure residual dipolar couplings (RDCs) to obtain structural information is advantageous when classical NMR parameters like the nuclear Overhauser effect (NOE) or J-couplings fail. Besides providing more accurate structural information, the alignment media can induce different orientations of enantiomers. In this study, we examined the ability of polyglutamates with different side-chain moieties─poly-γ-benzyl-l-glutamate (PBLG) and poly-γ-p-biphenylmethyl-l-glutamate (PBPMLG) ─to enantiodifferentiate the inherently chiral phenoxathiin-based thiacalix[4]arenes. Both media, in combination with two solvents, allowed for enantiodiscrimination, which was, to the best of our knowledge, proved for the first time on inherently chiral compounds. Moreover, using the experimental RDCs, we investigated the calix[4]arenes conformational preferences in solution, quantitatively analyzed the differences in the alignment of the enantiomers, and discussed the pitfalls of the use of the RDC analysis.
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Affiliation(s)
- Markéta Tichotová
- Laboratory
of NMR Spectroscopy, University of Chemistry
and Technology Prague (UCTP), Technická 5, 166 28Prague 6, Czech Republic
- Department
of Physical and Macromolecular Chemistry, Charles University, Hlavova 8, 128 00Prague 2, Czech Republic
- Institute
of Organic Chemistry and Biochemistry, Czech
Academy of Sciences, Flemingovo náměstí 542, 160 00Prague 6, Czech Republic
| | - Tomáš Landovský
- Department
of Organic Chemistry, University of Chemistry
and Technology Prague (UCTP), Technická 5, 166 28Prague 6, Czech Republic
| | - Jan Lang
- Faculty
of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16Prague 2, Czech Republic
| | - Sharon Jeziorowski
- Department
of Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 16, 64287Darmstadt, Germany
| | - Volker Schmidts
- Department
of Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 16, 64287Darmstadt, Germany
| | - Michal Kohout
- Department
of Organic Chemistry, University of Chemistry
and Technology Prague (UCTP), Technická 5, 166 28Prague 6, Czech Republic
| | - Martin Babor
- Department
of Solid State Chemistry, University of
Chemistry and Technology Prague (UCTP), Technická 5, 166 28Prague 6, Czech Republic
| | - Pavel Lhoták
- Department
of Organic Chemistry, University of Chemistry
and Technology Prague (UCTP), Technická 5, 166 28Prague 6, Czech Republic
| | - Christina M. Thiele
- Department
of Chemistry, Technical University of Darmstadt, Alarich-Weiss-Straße 16, 64287Darmstadt, Germany
| | - Hana Dvořáková
- Laboratory
of NMR Spectroscopy, University of Chemistry
and Technology Prague (UCTP), Technická 5, 166 28Prague 6, Czech Republic
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2
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Silva Elipe MV, Ndukwe IE, Murray JI. Cryogen-free 400-MHz nuclear magnetic resonance spectrometer as a versatile tool for pharmaceutical process analytical technology. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:512-534. [PMID: 38369696 DOI: 10.1002/mrc.5434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 02/20/2024]
Abstract
The discovery of new ceramic materials containing Ba-La-Cu oxides in 1986 that exhibited superconducting properties at high temperatures in the range of 35 K or higher, recognized with the Nobel Prize in Physics in 1987, opened a new world of opportunities for nuclear magnetic resonance (NMRs) and magnetic resonance imaging (MRIs) to move away from liquid cryogens. This discovery expands the application of high temperature superconducting (HTS) materials to fields beyond the chemical and medical industries, including electrical power grids, energy, and aerospace. The prototype 400-MHz cryofree HTS NMR spectrometer installed at Amgen's chemistry laboratory has been vital for a variety of applications such as structure analysis, reaction monitoring, and CASE-3D studies with RDCs. The spectrometer has been integrated with Amgen's chemistry and analytical workflows, providing pipeline project support in tandem with other Kinetic Analysis Platform technologies. The 400-MHz cryofree HTS NMR spectrometer, as the name implies, does not require liquid cryogens refills and has smaller footprint that facilitates installation into a chemistry laboratory fume hood, sharing the hood with a process chemistry reactor. Our evaluation of its performance for structural analysis with CASE-3D protocol and for reaction monitoring of Amgen's pipeline chemistry was successful. We envision that the HTS magnets would become part of the standard NMR and MRI spectrometers in the future. We believe that while the technology is being developed, there is room for all magnet options, including HTS, low temperature superconducting (LTS) magnets, and low field benchtop NMRs with permanent magnets, where utilization will be dependent on application type and costs.
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Affiliation(s)
| | - Ikenna Edward Ndukwe
- Department of Attribute Sciences, Process Development, Amgen Inc., Thousand Oaks, California, USA
| | - James I Murray
- Pivotal and Commercial Drug Substance Technologies, Process Development, Amgen Inc., Thousand Oaks, California, USA
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3
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Li GW, Wang XJ, Shi SH, Liu LT, Li JQ, Sun H, Wu ZQ, Lei X. Polyarylisocyanides Derived from an Alkyne-Pd(II) Catalyst as Robust Alignment Media with Excellent Enantiodiscimination. Anal Chem 2023; 95:18850-18858. [PMID: 38091507 DOI: 10.1021/acs.analchem.3c04240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
The development of chiral alignment media for measuring anisotropic NMR parameters provides an opportunity to determine the absolute configuration of chiral molecules without the need for derivatization. However, chiral alignment media with a high and robust enantiodiscriminating property for a wide range of chiral molecules are still scarce. In this study, we synthesized cholesterol-end-functionalized helical polyisocyanides from a chiral monomer using a cholesterol-based alkyne-Pd(II) initiator. These stereoregular polyisocyanides form stable and weak anisotropic lyotropic liquid crystals (LLCs) in dichloromethane systems, exhibiting highly optical activities in both single left- and right-handed helices. The preparation process of the media was straightforward, and the aligning property of the LLCs could be controlled by adjusting the concentration and temperature. Using the chiral polyisocyanides, we extracted the residual dipolar coupling for an enantiomeric pair of isopinocampheol (IPC), as well as a number of pharmaceutical molecules, demonstrating excellent enantiodiscriminating properties for a broad range of chiral compounds.
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Affiliation(s)
- Gao-Wei Li
- College of Chemistry and Chemical Engineering, Henan Engineering Research Center for Green Synthesis of Pharmaceuticals, Shangqiu Normal University, Shangqiu 476000, China
| | - Xiao-Juan Wang
- College of Chemistry and Chemical Engineering, Henan Engineering Research Center for Green Synthesis of Pharmaceuticals, Shangqiu Normal University, Shangqiu 476000, China
| | - Shuai-Hua Shi
- College of Chemistry and Chemical Engineering, Henan Engineering Research Center for Green Synthesis of Pharmaceuticals, Shangqiu Normal University, Shangqiu 476000, China
| | - Lan-Tao Liu
- College of Chemistry and Chemical Engineering, Henan Engineering Research Center for Green Synthesis of Pharmaceuticals, Shangqiu Normal University, Shangqiu 476000, China
| | - Jia-Qian Li
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, China
| | - Han Sun
- Research Unit of Structural Chemistry & Computational Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin 13125, Germany
- Institute of Chemistry, Technical University of Berlin, Berlin 10623, Germany
| | - Zong-Quan Wu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Xinxiang Lei
- State Key Laboratory of Applied Organic Chemistry, Lanzhou Magnetic Resonance Center, College of Chemistry and Chemi-cal Engineering, Lanzhou University, Lanzhou 730000, China
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, China
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4
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Silva Elipe MV, Ndukwe IE, Navarro-Vázquez A. Anisotropic NMR data acquisition with a prototype 400 MHz cryogen-free NMR spectrometer. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:530-543. [PMID: 37530063 DOI: 10.1002/mrc.5380] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 08/03/2023]
Abstract
High-temperature superconducting (HTS) materials have recently been incorporated into the construction of HTS cryogen-free magnets for nuclear magnetic resonance (NMR) spectroscopy. These HTS NMR spectrometers do not require liquid cryogens, thereby providing significant cost savings and facilitating easy integration into chemistry laboratories. However, the optimal performance of these HTS magnets against standard cryogen NMR magnets must be evaluated, especially with demanding modern NMR applications such as NMR in anisotropic media. The stability of the HTS magnets over time and their performance with complex pulse sequence experiments are the main unknown factors of this new technology. In this study, we evaluate the utility of our prototype 400 MHz cryogen-free power-driven HTS NMR spectrometer, installed in the fumehood of a chemistry laboratory, for stereochemical analysis of three commercial natural products (artemisinin, artemether, and dihydroartemisinin) via measurement of anisotropic NMR data, in particular, residual dipolar couplings. The accuracy of measurement of the anisotropic NMR data with the HTS magnet spectrometer is evaluated through the CASE-3D fitting protocol, as implemented in the Mestrenova-StereoFitter software program.
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Affiliation(s)
| | | | - Armando Navarro-Vázquez
- Departmento de Química Fundamental, Centro de Ciências Exatas e da Natureza, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
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5
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Carvalho DS, da Silva DGB, Hallwass F, Navarro-Vázquez A. An Acrylonitrile-Based Copolymer Gel as an NMR Alignment Medium for Extraction of Residual Dipolar Couplings of Small Molecules in Aqueous Solution. Chempluschem 2023; 88:e202200446. [PMID: 36782376 DOI: 10.1002/cplu.202200446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/19/2023] [Indexed: 01/24/2023]
Abstract
An NMR weakly-aligning polymer gel has been prepared by copolymerization of acrylonitrile and 2-acrylamide-2-methyl-1-propanesulfonic acid in the presence of 1,4-butanediol diacrylate as a cross-linker. The polymer readily swells in water in a large range of temperatures, although the swelling ratio is decreased in saline solutions. The swollen gel can be mechanically compressed, in a reversible way, generating anisotropy, as easily shown in 2 H NMR experiments, and allowing measurement of 1 DCH residual dipolar couplings (RDCs) through F1-coupled HSQC experiments. The performance of this gel as a NMR alignment medium was evaluated in several water-soluble organic molecules and, while it provided RDCs of proper size for sucrose and even such as small molecule as 5-norbornen-2-ol, in the case of azidothymidine and cefuroxime sodium salt the strong interaction of these molecules with the gel prevented successful extraction of the RDCs.
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Affiliation(s)
- Daiane S Carvalho
- Departamento de Química Fundamental, Universidade Federal de Pernambuco Cidade Universitria, CEP, 50.740-540, Recife, PE, Brazil
| | - Danilo G B da Silva
- Departamento de Química Fundamental, Universidade Federal de Pernambuco Cidade Universitria, CEP, 50.740-540, Recife, PE, Brazil
| | - Fernando Hallwass
- Departamento de Química Fundamental, Universidade Federal de Pernambuco Cidade Universitria, CEP, 50.740-540, Recife, PE, Brazil
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, Universidade Federal de Pernambuco Cidade Universitria, CEP, 50.740-540, Recife, PE, Brazil
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6
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Watson JD, Field LD, Ball GE. [Fp(CH 4)] +, [η 5-CpRu(CO) 2(CH 4)] +, and [η 5-CpOs(CO) 2(CH 4)] +: A Complete Set of Group 8 Metal-Methane Complexes. J Am Chem Soc 2022; 144:17622-17629. [PMID: 36121779 DOI: 10.1021/jacs.2c07124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Here, we report the NMR spectroscopic analysis of the group 8 transition metal methane σ-complexes [η5-CpM(CO)2(CH4)][Al(OC(CF3)3)4] (M = Fe, Ru) at -90 °C in the weakly coordinating solvent 1,1,1,3,3,3-hexafluoropropane. The iron(II)-methane complex has a 1H resonance at δ -4.27, a 13C resonance at δ -53.0, and 1JC-H = 126 Hz for the bound methane fragment. The ruthenium(II)-methane complex has a 1H resonance at δ -2.10, a 13C resonance at δ -48.8, and a 1JC-H = 126 Hz for the bound methane fragment. DFT and ab initio calculations support these experimental observations and provide further detail on the structures of the [η5-CpM(CO)2(CH4)]+ (M = Fe, Ru) complexes of the Group 8 metals. Both the iron centered methane complex, [η5-CpFe(CO)2(CH4)][Al(OC(CF3)3)4], and the ruthenium centered methane complex, [η5-CpRu(CO)2(CH4)][Al(OC(CF3)3)4], are significantly less stable than the previously reported osmium-methane complex [η5-CpOs(CO)2(CH4)][Al(OC(CF3)3)4].
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Affiliation(s)
- James D Watson
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
| | - Leslie D Field
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
| | - Graham E Ball
- School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia
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7
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Fuentes-Monteverde JCC, Nath N, Forero AM, Balboa EM, Navarro-Vázquez A, Griesinger C, Jiménez C, Rodríguez J. Connection of Isolated Stereoclusters by Combining 13C-RCSA, RDC, and J-Based Configurational Analyses and Structural Revision of a Tetraprenyltoluquinol Chromane Meroterpenoid from Sargassum muticum. Mar Drugs 2022; 20:462. [PMID: 35877755 PMCID: PMC9319238 DOI: 10.3390/md20070462] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/06/2022] [Accepted: 07/15/2022] [Indexed: 12/10/2022] Open
Abstract
The seaweed Sargassum muticum, collected on the southern coast of Galicia, yielded a tetraprenyltoluquinol chromane meroditerpene compound known as 1b, whose structure is revised. The relative configuration of 1b was determined by J-based configurational methodology combined with an iJ/DP4 statistical analysis and further confirmed by measuring two anisotropic properties: carbon residual chemical shift anisotropies (13C-RCSAs) and one-bond 1H-13C residual dipolar couplings (1DCH-RDCs). The absolute configuration of 1b was deduced by ECD/OR/TD-DFT methods and established as 3R,7S,11R.
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Affiliation(s)
- Juan Carlos C. Fuentes-Monteverde
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
- NMR Based Structural Biology, MPI for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Nilamoni Nath
- Department of Chemistry, Gauhati University, Gopinath Bardoloi Nagar, Guwahati 781014, India;
| | - Abel M. Forero
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
| | - Elena M. Balboa
- Department of Chemical Engineering, Faculty of Science, Campus Ourense, University of Vigo, As Lagoas s/n, 32004 Ourense, Spain;
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, CCEN, Universidade Federal de Pernambuco, Cidade Universitária, Recife 50740-550, Brazil;
| | - Christian Griesinger
- NMR Based Structural Biology, MPI for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| | - Carlos Jiménez
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
| | - Jaime Rodríguez
- Departamento de Química e Centro de Investigacións Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain; (J.C.C.F.-M.); (A.M.F.)
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8
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Yu G, Wang G, Duan M, Jiang B, Zhang X, Li C, He L, Liu M. Self-Assembled Oligopeptide (FK) 4 as a Chiral Alignment Medium for the Anisotropic NMR Analysis of Organic Compounds. ACS APPLIED MATERIALS & INTERFACES 2022; 14:29223-29229. [PMID: 35712808 DOI: 10.1021/acsami.2c05506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Anisotropic NMR parameters have been proven to be powerful for the structural elucidation of organic molecules. Herein, we present an alignment medium based on the self-assembled (FK)4 oligopeptide, showing excellent properties in measurements of anisotropic NMR parameters in both D2O and CD3OD. The preparation of the (FK)4-based alignment medium is simple and rapid. The low viscosity of the anisotropic phase makes it easy to be transferred to the NMR tube. The alignment of the oligopeptide is fast, stable, and homogeneous, with weak background signals, permitting the acquirement of high-quality NMR spectra. The performance of this alignment medium in residual dipolar coupling measurements and diastereomer discriminations is demonstrated by analyzing several different analytes. The enantiodiscrimination property of the (FK)4 oligopeptide is revealed by the difference of residual chemical shift anisotropy of the two enantiomers in the 1D 13C spectrum, granting its potential use for the quantification and identification of enantiomers of small molecules.
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Affiliation(s)
- Gangjin Yu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guan Wang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mojie Duan
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin Jiang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xu Zhang
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Conggang Li
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lichun He
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Maili Liu
- State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Optics Valley Laboratory, Hubei 430074, China
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9
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Knoll K, Herold D, Hirschmann M, Thiele CM. A supramolecular and liquid crystalline water-based alignment medium based on azobenzene-substituted 1,3,5-benzenetricarboxamides. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2022; 60:563-571. [PMID: 35266585 DOI: 10.1002/mrc.5266] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/04/2022] [Accepted: 03/07/2022] [Indexed: 06/14/2023]
Abstract
A supramolecular, lyotropic liquid crystalline alignment medium based on an azobenzene-containing 1,3,5-benzenetricarboxamide (BTA) building block is described and investigated. As we demonstrate, this water-based system is suitable for the investigation of various water-soluble analytes and allows for a scaling of alignment strength through variation of temperature. Additionally, alignment is shown to reversibly collapse above a certain temperature, yielding an isotropic solution. This collapse allows for isotropic reference measurements, which are typically needed in addition to those in an anisotropic environment, to be performed using the same sample just by varying the temperature. The medium described thus provides easy access to anisotropic NMR observables and simplifies structure elucidation techniques based thereon.
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Affiliation(s)
- Kevin Knoll
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Darmstadt, Germany
| | - Dominik Herold
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Darmstadt, Germany
| | - Max Hirschmann
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Darmstadt, Germany
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Christina M Thiele
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Darmstadt, Germany
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10
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Abstract
The σ-alkane complexes of transition metals, which contain an essentially intact alkane molecule weakly bound to the metal, have been well established as crucial intermediates in the activation of the strong C-H σ-bonds found in alkanes. Methane, the simplest alkane, binds even more weakly than larger alkanes. Here we report an example of a long-lived methane complex formed by directly binding methane as an incoming ligand to a reactive organometallic complex. Photo-ejection of carbon monoxide from a cationic osmium-carbonyl complex dissolved in an inert hydrofluorocarbon solvent saturated with methane at -90 °C affords an osmium(II) complex, [η5-CpOs(CO)2(CH4)]+, containing methane bound to the metal centre. Nuclear magnetic resonance (NMR) spectroscopy confirms the identity of the σ-methane complex and shows that the four protons of the metal-bound methane are in rapid exchange with each other. The methane ligand has a characteristically shielded 1H NMR resonance (δ -2.16), and the highly shielded carbon resonance (δ -56.3) shows coupling to the four attached protons (1JC-H = 127 Hz). The methane complex has an effective half-life of about 13 hours at -90 °C.
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11
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Wu YS, Li BX, Long YY. Rapid quantitative 1H- 13C two-dimensional NMR with high precision. RSC Adv 2022; 12:5349-5356. [PMID: 35425561 PMCID: PMC8981411 DOI: 10.1039/d1ra08423b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 02/06/2022] [Indexed: 12/03/2022] Open
Abstract
Two dimensional (2D) 1H-13C heteronuclear single-quantum correlation (HSQC) spectroscopy has recently been proposed for quantitative determination of typical linear low density polyethylene (LLDPE) with high accuracy. It requires highly precise measurement to achieve further reliable quantification. In this context, this paper aims at determining conditions that allow the achievement of high precision. On the basis of the optimized parameters, two time-saving strategies, nonuniform sampling (NUS) and band-selective HSQC are evaluated on model polyolefins in terms of repeatability. Precision better than 0.3% and 5% for ethylene content (E mol%) and 1-hexene content (H mol%) of the model poly(ethylene-co-1-hexene)s are obtained with 50% NUS or band-selective HSQC. Moreover, dramatic precision enhancements can be achieved with the combination of band-selective HSQC and 50% NUS, in which repeatabilities better than 0.15% and 2.5% for E mol% and H mol% are observed. The experiment times are reduced to about 0.5 h. These methods open important perspectives for rapid, precise and accurate quantitative analysis of complex polymers.
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Affiliation(s)
- Yu-Shan Wu
- Jilin Business and Technology College Changchun 130507 China
| | - Bai-Xiang Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun 130022 China
| | - Ying-Yun Long
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun 130022 China
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12
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Roth FA, Schmidts V, Rettig J, Thiele CM. Model free analysis of experimental residual dipolar couplings in small organic compounds. Phys Chem Chem Phys 2021; 24:281-286. [PMID: 34881759 DOI: 10.1039/d1cp02324a] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Residual dipolar couplings (RDCs) contain information on the relative arrangement and dynamics of internuclear spin vectors in chemical compounds. Classically, RDC data is analyzed by fitting to structure models, while model-free approaches (MFA) directly relate RDCs to the corresponding internuclear vectors. The recently introduced software TITANIA implements the MFA and extracts structure and dynamics parameters directly from RDCs to facilitate de novo structure refinement for small organic compounds. Encouraged by our previous results on simulated data, we herein focus on the prerequisites and challenges faced when using purely experimental data for this approach. These concern mainly the fact that not all couplings are accessible in all media, leading to voids in the RDC matrix and the concomitant effects on the structure refinement. It is shown that RDC data sets obtained experimentally from currently available alignment media and measurement methods are of sufficient quality to allow relative configuration determination even when the relative configuration of the analyte is completely unknown.
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Affiliation(s)
- Felix A Roth
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany.
| | - Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany.
| | - Jan Rettig
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany.
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany.
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13
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Roth FA, Schmidts V, Thiele CM. TITANIA: Model-Free Interpretation of Residual Dipolar Couplings in the Context of Organic Compounds. J Org Chem 2021; 86:15387-15402. [PMID: 34677977 DOI: 10.1021/acs.joc.1c01926] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Residual dipolar couplings (RDCs) become increasingly important as additional NMR parameters in the structure elucidation of organic compounds but are usually used in fitting procedures to discriminate between (computed) structures that are in accordance with RDCs and others that can be ruled out. Thus, the determination of configurations requires prior structural information. The direct use of RDCs as restraints to construct structures based on RDCs has only recently begun also in organic compounds. No protocol has been published though that uses the vector and dynamics information available in multialignment data sets directly for the joint determination of conformation and configuration of organic compounds. This is proposed in the current study. We show that by employing these data, even a flat or random start structure converges into the correctly configured structure when employing multiple alignment data sets in our iterative procedure. The requirements in terms of the number of RDCs and alignment media necessary are discussed in detail.
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Affiliation(s)
- Felix A Roth
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany
| | - Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technical University of Darmstadt, Alarich-Weiss-Str. 16, 64287 Darmstadt, Germany
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14
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Long YY, Lv J, Li BX, Liu YG. Speedy quantitative microstructure determination of Poly(ethylene-co-1-hexene) at triads by 1H–13C two-dimensional NMR. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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15
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da Silva DGB, Hallwass F, Navarro-Vázquez A. Single experiment measurement of residual dipolar couplings in aqueous solution using a biphasic bisperylene imide chromonic liquid crystal. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:408-413. [PMID: 33295034 DOI: 10.1002/mrc.5120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/01/2020] [Accepted: 12/06/2020] [Indexed: 06/12/2023]
Abstract
The use of the biphasic isotropic/nematic region in a bisperylene imide-based lyotropic liquid crystal system allows the extraction of proton-carbon 1 DCH residual dipolar couplings in aqueous solution from a single F1-coupled HSQC experiment. The method was successfully applied to the RDC-based conformational analysis of sucrose.
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Affiliation(s)
- Danilo G B da Silva
- Departamento de Química Fundamental, CCEN, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Fernando Hallwass
- Departamento de Química Fundamental, CCEN, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, CCEN, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
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16
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Pedersen CP, Prestel A, Teilum K. Software for reconstruction of nonuniformly sampled NMR data. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:315-323. [PMID: 32516838 DOI: 10.1002/mrc.5060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
Nonuniform sampling (NUS) of multidimensional NMR experiments is a powerful tool to obtain high-resolution spectra with less instrument time. With NUS, only a subset of the points needed for conventional Fourier transformation is recorded, and sophisticated algorithms are needed to reconstruct the missing data points. During the last decade, several software packages implementing the reconstruction algorithms have emerged and been refined and now result in spectra of almost similar quality as spectra from conventionally recorded and processed data. However, from the number of literature references to the reconstruction methods, many more multidimensional NMR spectra could presumably be recorded with NUS. To help researchers considering to start using NUS for their NMR experiments, we here review 13 different reconstruction methods found in five software packages (CambridgeCS, hmsIST, MddNMR, NESTA-NMR, and SMILE). We have compared how the methods run with the provided example scripts for reconstructing a nonuniform sampled three-dimensional 15 N-NOESY-HSQC at sampling densities from 5% to 50%. Overall, the spectra are all of similar quality above 20% sampling density. Thus, without any particular knowledge about the details of the reconstruction algorithms, significant reduction in the experiment time can be achieved. Below 20% sampling density, the intensities of particular weak peaks start being affected. MddNMR's IST with virtual echo and the SMILE algorithms still reproduced the spectra with the highest accuracy of peak intensities.
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Affiliation(s)
- Christian Parsbaek Pedersen
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Andreas Prestel
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Kaare Teilum
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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17
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Qin S, Jiang Y, Sun H, Liu H, Zhang A, Lei X. Measurement of Residual Dipolar Couplings of Organic Molecules in Multiple Solvent Systems Using a Liquid‐Crystalline‐Based Medium. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Si‐Yong Qin
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
| | - Yan Jiang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
| | - Han Sun
- Section of Structural Biology Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) 13125 Berlin Germany
| | - Han Liu
- School of Pharmaceutical Sciences South-Central University for Nationalities Wuhan 430074 China
| | - Ai‐Qing Zhang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
| | - Xinxiang Lei
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
- School of Pharmaceutical Sciences South-Central University for Nationalities Wuhan 430074 China
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18
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Qin S, Jiang Y, Sun H, Liu H, Zhang A, Lei X. Measurement of Residual Dipolar Couplings of Organic Molecules in Multiple Solvent Systems Using a Liquid‐Crystalline‐Based Medium. Angew Chem Int Ed Engl 2020; 59:17097-17103. [DOI: 10.1002/anie.202007243] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Si‐Yong Qin
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
| | - Yan Jiang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
| | - Han Sun
- Section of Structural Biology Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) 13125 Berlin Germany
| | - Han Liu
- School of Pharmaceutical Sciences South-Central University for Nationalities Wuhan 430074 China
| | - Ai‐Qing Zhang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
| | - Xinxiang Lei
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science South-Central University for Nationalities Wuhan 430074 China
- School of Pharmaceutical Sciences South-Central University for Nationalities Wuhan 430074 China
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19
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Liu H, Chen P, Li XL, Sun H, Lei X. Practical aspects of oligopeptide AAKLVFF as an alignment medium for the measurements of residual dipolar coupling of organic molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2020; 58:404-410. [PMID: 32239576 DOI: 10.1002/mrc.4825] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/03/2018] [Accepted: 12/26/2018] [Indexed: 06/11/2023]
Abstract
Practical aspects of the oligopeptide AAKLVFF as an alignment medium are discussed, including large-scale synthesis of the oligopeptide, detailed description of preparation of the alignment medium, and acquisition of the RDCs. The resulting orienting medium is stable and highly homogeneous with tunable alignment strength in methanol.
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Affiliation(s)
- Han Liu
- School of Pharmaceutical Sciences, South Central University for Nationalities, Wuhan, China
| | - Pian Chen
- School of Pharmaceutical Sciences, South Central University for Nationalities, Wuhan, China
| | - Xiao-Lu Li
- Department of Structural Biology, Leibniz-Institut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Han Sun
- Department of Structural Biology, Leibniz-Institut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | - Xinxiang Lei
- School of Pharmaceutical Sciences, South Central University for Nationalities, Wuhan, China
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20
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Carvalho DS, da Silva DGB, Hallwass F, Navarro-Vázquez A. Chemically cross-linked polyacrylonitrile. A DMSO compatible NMR alignment medium for measurement of residual dipolar couplings and residual chemical shift anisotropies. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 302:21-27. [PMID: 30933840 DOI: 10.1016/j.jmr.2019.03.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 03/09/2019] [Accepted: 03/14/2019] [Indexed: 06/09/2023]
Abstract
Chemically cross-linked polyacrylontrile polymer gels, have been prepared as an alignment medium compatible with DMSO-d6. These gels allow measurement of residual dipolar couplings (RDCs) and residual chemical shift anisotropies (RCSAs) with good accuracy as tested with brucine and α-santonin natural compounds. The gels can be reversibly compressed allowing easy measurement of RCSAs. They also present good physical homogeneity, clean HSQC spectra with little background 1H signals, and allow unambiguous referencing of 13C spectra for RCSA extraction.
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Affiliation(s)
- Daiane S Carvalho
- Universidade Federal de Pernambuco, Departamento de Química Fundamental, CCEN, Recife, Pernambuco 50670-901, Brazil
| | - Danilo G B da Silva
- Universidade Federal de Pernambuco, Departamento de Química Fundamental, CCEN, Recife, Pernambuco 50670-901, Brazil
| | - Fernando Hallwass
- Universidade Federal de Pernambuco, Departamento de Química Fundamental, CCEN, Recife, Pernambuco 50670-901, Brazil
| | - Armando Navarro-Vázquez
- Universidade Federal de Pernambuco, Departamento de Química Fundamental, CCEN, Recife, Pernambuco 50670-901, Brazil.
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21
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Knoll K, Leyendecker M, Thiele CM. l
‐Valine Derivatised 1,3,5‐Benzene‐Tricarboxamides as Building Blocks for a New Supramolecular Organogel‐Like Alignment Medium. European J Org Chem 2019. [DOI: 10.1002/ejoc.201801306] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Kevin Knoll
- Technische Universität Darmstadt Clemens‐Schöpf Institut für Organische Chemie und Biochemie Alarich‐Weiss‐Str. 4 64287 Darmstadt Germany
| | - Martin Leyendecker
- Technische Universität Darmstadt Clemens‐Schöpf Institut für Organische Chemie und Biochemie Alarich‐Weiss‐Str. 4 64287 Darmstadt Germany
| | - Christina M. Thiele
- Technische Universität Darmstadt Clemens‐Schöpf Institut für Organische Chemie und Biochemie Alarich‐Weiss‐Str. 4 64287 Darmstadt Germany
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22
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Farley KA, Che Y, Navarro-Vázquez A, Limberakis C, Anderson D, Yan J, Shapiro M, Shanmugasundaram V, Gil RR. Cyclic Peptide Design Guided by Residual Dipolar Couplings, J-Couplings, and Intramolecular Hydrogen Bond Analysis. J Org Chem 2019; 84:4803-4813. [PMID: 30605335 DOI: 10.1021/acs.joc.8b02811] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cyclic peptides have long tantalized drug designers with their potential ability to combine the best attributes of antibodies and small molecules. An ideal cyclic peptide drug candidate would be able to recognize a protein surface like an antibody while achieving the oral bioavailability of a small molecule. It has been hypothesized that such cyclic peptides balance permeability and solubility using their solvent-dependent conformational flexibility. Herein we report a conformational deconvolution NMR methodology that combines residual dipolar couplings, J-couplings, and intramolecular hydrogen bond analysis along with conformational analysis using molecular dynamics simulations and density functional theory calculations for studying cyclic peptide conformations in both low-dielectric solvent (chloroform) and high-dielectric solvent (DMSO) to experimentally study the solvent-dependent conformational change hypothesis. Taken together, the combined experimental and computational approaches can illuminate conformational ensembles of cyclic peptides in solution and help identify design opportunities for better permeability.
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Affiliation(s)
- Kathleen A Farley
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Ye Che
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, CCEN , Universidade Federal de Pernambuco , Cidade Universitária, Recife , PE 50740-560 , Brazil
| | - Chris Limberakis
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Dennis Anderson
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Jiangli Yan
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Michael Shapiro
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Veerabahu Shanmugasundaram
- Medicinal Sciences, Pfizer Worldwide R&D , Eastern Point Road , Groton , Connecticut 06340 , United States
| | - Roberto R Gil
- Department of Chemistry , Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States
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23
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Application of anisotropic NMR parameters to the confirmation of molecular structure. Nat Protoc 2018; 14:217-247. [DOI: 10.1038/s41596-018-0091-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Castro SJ, García ME, Padrón JM, Navarro-Vázquez A, Gil RR, Nicotra VE. Phytochemical Study of Senecio volckmannii Assisted by CASE-3D with Residual Dipolar Couplings and Isotropic 1H/ 13C NMR Chemical Shifts. JOURNAL OF NATURAL PRODUCTS 2018; 81:2329-2337. [PMID: 30359016 DOI: 10.1021/acs.jnatprod.8b00162] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nine new eremophilanolides, with seven known sesquiterpenoids, and 4-hydroxyacetophenone were isolated from the aerial parts of Senecio volckmannii var. volckmannii. The structures of these compounds were fully characterized using a combination of spectroscopic techniques including multinuclear and multidimensional NMR and mass spectrometry. The recently published Computer Assisted 3D Structure Elucidation (CASE-3D) protocol was applied in the configurational and conformational analysis of many of these eremophilanolides on the basis of Residual Dipolar Couplings (RDCs) and/or DFT predicted 1H/13C chemical shifts.
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Affiliation(s)
- Sebastián J Castro
- Facultad de Ciencias Químicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET) , Universidad Nacional de Córdoba , Casilla de Correo 495 , 5000 Córdoba , Argentina
| | - Manuela E García
- Facultad de Ciencias Químicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET) , Universidad Nacional de Córdoba , Casilla de Correo 495 , 5000 Córdoba , Argentina
| | - José M Padrón
- BioLab, Instituto Universitario de Bio-Orgánica "Antonio González" (IUBO-AG), Centro de Investigaciones Biomédicas de Canarias (CIBICAN) , Universidad de La Laguna , C/Astrofísico Francisco Sánchez 2 , 38206 La Laguna , Spain
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, CCEN , Universidade Federal de Pernambuco , Avenida Professor Moraes Rego, 1235, Cidade Universitáaria , 50670-901 Recife , PE , Brazil
| | - Roberto R Gil
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Viviana E Nicotra
- Facultad de Ciencias Químicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET) , Universidad Nacional de Córdoba , Casilla de Correo 495 , 5000 Córdoba , Argentina
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25
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Jeziorowski S, Thiele CM. Poly‐γ‐
p
‐Biphenylmethyl‐Glutamate as Enantiodifferentiating Alignment Medium for NMR Spectroscopy with Temperature‐Tunable Properties. Chemistry 2018; 24:15631-15637. [DOI: 10.1002/chem.201802921] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Sharon Jeziorowski
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie Technische Universität Darmstadt Alarich-Weiss-Str. 4 64287 Darmstadt Germany
| | - Christina M. Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie Technische Universität Darmstadt Alarich-Weiss-Str. 4 64287 Darmstadt Germany
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26
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Marcó N, Gil RR, Parella T. Isotropic/Anisotropic NMR Editing by Resolution-Enhanced NMR Spectroscopy. Chemphyschem 2018; 19:1024-1029. [PMID: 29384256 DOI: 10.1002/cphc.201800094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Indexed: 11/11/2022]
Abstract
Modern resolution-enhanced NMR techniques can monitor the in situ discrimination of co-existing isotropic and anisotropic contributions of small molecules dissolved in weakly aligning PMMA/CDCl3 media. The simultaneous sign-sensitive determination of accurate Δδiso-aniso (1 H), Δδiso-aniso (13 C) and/or isotropic 1 JCH and anisotropic 1 TCH coupling constants (and consequently 1 H-13 C residual dipolar couplings and 1 H/13 C residual chemical shift anisotropies) can be performed from spectral-aliased heteronuclear single-quantum correlation spectra.
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Affiliation(s)
- Núria Marcó
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, 08193, Bellaterra, Catalonia, Spain
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, 15213, PA, USA
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, 08193, Bellaterra, Catalonia, Spain
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27
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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.
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Affiliation(s)
- Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Catalonia, Spain
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28
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Navarro-Vázquez A, Gil RR, Blinov K. Computer-Assisted 3D Structure Elucidation (CASE-3D) of Natural Products Combining Isotropic and Anisotropic NMR Parameters. JOURNAL OF NATURAL PRODUCTS 2018; 81:203-210. [PMID: 29323895 DOI: 10.1021/acs.jnatprod.7b00926] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A computer-assisted structural elucidation (CASE-3D) strategy based on the use of isotropic and/or anisotropic NMR data is proposed to elucidate relative configuration and preferred conformation in complex natural products. The methodology involves the selection of conformational models through the use of the Akaike Information Criterion and scoring of the different configurations. As illustrative examples, the methodology furnished the correct configuration of the already known compounds artemisinin (1) and homodimericin A (2). Revised structures (5 and 6), including their absolute configuration, for the recently reported curcusones I (3) and J (4) are proposed.
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Affiliation(s)
- Armando Navarro-Vázquez
- Departamento de Química Fundamental, Universidade Federal de Pernambuco , Avenida Professor Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University , 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Kirill Blinov
- MestReLab Research S. L. Feliciano Barrera , 9 Baixo, Santiago de Compostela, A Coruña, 15706 Spain
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29
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Souza AA, Gil RR, Parella T. Highly resolved HSQC experiments for the fast and accurate measurement of homonuclear and heteronuclear coupling constants. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 282:54-61. [PMID: 28759743 DOI: 10.1016/j.jmr.2017.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/10/2017] [Accepted: 07/13/2017] [Indexed: 06/07/2023]
Abstract
A number of J-upscaled NMR experiments are currently available to measure coupling constants along the indirect F1 dimension of a 2D spectrum. A major drawback is the limited F1 digital resolution that requires long acquisition times in order to achieve reasonably accurate measures. Here is shown how high levels of F1 digital resolution in a multiple-purpose HSQC experiment can be easily achieved by implementing a general J/δ-scaling strategy. In particular, a set of new J-resolved HSQC experiments is presented for a faster and much more accurate J determination in small molecules. Several options and practical aspects are discussed and exemplified by measuring the magnitude and/or the sign of several homo- and heteronuclear coupling constants in one shot.
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Affiliation(s)
- 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, 64049-550 Teresina, PI, Brazil
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Catalonia, Spain.
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30
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Reller M, Wesp S, Koos MRM, Reggelin M, Luy B. Biphasic Liquid Crystal and the Simultaneous Measurement of Isotropic and Anisotropic Parameters by Spatially Resolved NMR Spectroscopy. Chemistry 2017. [DOI: 10.1002/chem.201702126] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Malin Reller
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Svenja Wesp
- Organische Chemie; Technische Universität Darmstadt; Alarich-Weiss Str. 4 64287 Darmstadt Germany
| | - 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
| | - Michael Reggelin
- Organische Chemie; Technische Universität Darmstadt; Alarich-Weiss Str. 4 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
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31
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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.
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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
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Li GW, Cao JM, Zong W, Hu L, Hu ML, Lei X, Sun H, Tan RX. Helical Polyisocyanopeptides as Lyotropic Liquid Crystals for Measuring Residual Dipolar Couplings. Chemistry 2017; 23:7653-7656. [DOI: 10.1002/chem.201700539] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Gao-Wei Li
- Institute of Functional Biomolecules; State Key Laboratory of Pharmaceutical Biotechnology; Nanjing University; Nanjing 210093 P. R. China
| | - Jiang-Ming Cao
- Institute of Functional Biomolecules; State Key Laboratory of Pharmaceutical Biotechnology; Nanjing University; Nanjing 210093 P. R. China
| | - Wen Zong
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Li Hu
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Mao-Lin Hu
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Xinxiang Lei
- School of Pharmaceutical Sciences; South Central University for Nationalities; Wuhan 430074 P. R. China
- College of Chemistry & Materials Engineering; Wenzhou University; Wenzhou 325035 P. R. China
| | - Han Sun
- Leibniz-Institut für Molekulare Pharmakologie (FMP); Robert-Roessle-Strasse 10 13125 Berlin Germany
| | - Ren Xiang Tan
- Institute of Functional Biomolecules; State Key Laboratory of Pharmaceutical Biotechnology; Nanjing University; Nanjing 210093 P. R. China
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Navarro-Vázquez A, Berdagué P, Lesot P. Integrated Computational Protocol for the Analysis of Quadrupolar Splittings from Natural-Abundance Deuterium NMR Spectra in (Chiral) Oriented Media. Chemphyschem 2017; 18:1252-1266. [DOI: 10.1002/cphc.201601423] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Armando Navarro-Vázquez
- Departamento de Química Fundamental; Universidade Federal de Pernambuco Cidade Universitária; CEP: 50 740-540 Recife PE Brazil
- Institute of Organic Chemistry and Institute for Biological Interfaces; Karlsruhe Institute of Technology (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe German
| | - Philippe Berdagué
- RMN en Milieu Orienté; ICMMO; UMR CNRS 8182; Université Paris-Sud/Université Paris-Saclay; Bât. 410 91405 Orsay cedex France
| | - Philippe Lesot
- RMN en Milieu Orienté; ICMMO; UMR CNRS 8182; Université Paris-Sud/Université Paris-Saclay; Bât. 410 91405 Orsay cedex France
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França JAA, Navarro-Vázquez A, Lei X, Sun H, Griesinger C, Hallwass F. Complete NMR assignment and conformational analysis of 17-α-ethinylestradiol by using RDCs obtained in grafted graphene oxide. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:297-303. [PMID: 27637176 DOI: 10.1002/mrc.4526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/08/2016] [Accepted: 09/13/2016] [Indexed: 06/06/2023]
Abstract
The 1 H and 13 C NMR spectra of 17-α-ethinylestradiol (EE2), a well-known contraceptive, including diastereotopic methylene groups, were fully assigned with the help of residual dipolar couplings (RDC) measured in the recently developed grafted graphene oxide orienting medium. RDC analysis, which included all 1 DCH couplings and the long-range 2 DCH1 H-C≡13 C coupling, also pointed to the presence of a minor conformation arising from pseudo-rotation of the steroid B ring. Saturation-transfer difference (STD) measurements revealed that the most likely interaction between EE2 and orienting medium occurred on the C and D ring. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- José A A França
- Instituto Federal de Alagoas, Campus Piranhas, Avenida Sergipe, s/n° Xingó, 57460-000, Piranhas, AL, Brazil
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, 1235, Cidade Universitária, 50670-901, Recife, PE, Brazil
| | - Xinxiang Lei
- School of Pharmaceutical Sciences, South Central University for Nationalities, Wuhan, 430074, PR China
| | - Han Sun
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Robert-Rössle-StraΒe 10, 13125, Berlin, Germany
| | - Christian Griesinger
- Department of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Fassberg 11, 37077, Göttingen, Germany
| | - Fernando Hallwass
- Departamento de Química Fundamental, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, 1235, Cidade Universitária, 50670-901, Recife, PE, Brazil
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García ME, Woodruff SR, Hellemann E, Tsarevsky NV, Gil RR. Di(ethylene glycol) methyl ether methacrylate (DEGMEMA)-derived gels align small organic molecules in methanol. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:206-209. [PMID: 26763068 DOI: 10.1002/mrc.4400] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 10/20/2015] [Accepted: 11/24/2015] [Indexed: 05/28/2023]
Abstract
Residual dipolar couplings (RDCs) constitute an important NMR parameter for structural elucidation in all areas of chemistry. In this study, di(ethylene glycol) methyl ether methacrylate (DEGMEMA)-based gels are introduced as alignment media for the measurement of RDCs of small organic molecules in polar solvents such as methanol. The low viscosity of methanol permits the execution of J-scaled BIRD HSQC experiments that yield very sharp lines in anisotropic conditions. The gels have excellent mechanical properties, and their compression and expansion in the swollen state can be reversed and performed multiple times. This process enables the easy loading and release of analytes. The excellent performance of these new aligning gels is demonstrated by analyzing the structure of the alkaloid retrorsine. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Manuela E García
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
- Department of Organic Chemistry, National University of Cordoba, Medina Allende y Haya de La Torre, Cordoba, 5000, Argentina
| | - Shannon R Woodruff
- Department of Chemistry, Southern Methodist University, Dallas, TX, USA
- Center for Drug Discovery, Design, and Delivery in Dedman College, Southern Methodist University, Dallas, TX, USA
| | - Erich Hellemann
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
| | - Nicolay V Tsarevsky
- Department of Chemistry, Southern Methodist University, Dallas, TX, USA
- Center for Drug Discovery, Design, and Delivery in Dedman College, Southern Methodist University, Dallas, TX, USA
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
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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.
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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.
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37
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Saurí J, Parella T, Williamson RT, Martin GE. Improving the performance of J-modulated ADEQUATE experiments through homonuclear decoupling and non-uniform sampling. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:191-197. [PMID: 26332452 DOI: 10.1002/mrc.4322] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 07/17/2015] [Accepted: 07/27/2015] [Indexed: 06/05/2023]
Abstract
Homonuclear 13 C-13 C couplings at natural abundance can be measured using the J-modulated Adequate DoublE QUAntumTransfer Experiment (ADEQUATE) experiment. To somewhat ameliorate F1 digitization requirements, a scaling factor was incorporated into the original pulse sequence. Non-uniform sampling provides an obvious avenue to further facilitate the acquisition of 1 JCC and n JCC homonuclear coupling constant data. We introduce homonuclear decoupling (HD) analogous to that described for the 1,1-HD-ADEQUATE and 1,n-HD-ADEQUATE experiments and evaluate the combination of non-uniform sampling and HD on the acquisition of both 1 JCC and n JCC homonuclear 13 C-13 C coupling constants using ibuprofen as a model compound. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Josep Saurí
- Process and Analytical Chemistry, NMR Structure Elucidation, Merck Research Laboratories, Rahway, NJ, 07065, USA
| | - Teodor Parella
- Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona, 08193, Bellaterra (Barcelona), Catalonia, Spain
| | - R Thomas Williamson
- Process and Analytical Chemistry, NMR Structure Elucidation, Merck Research Laboratories, Rahway, NJ, 07065, USA
| | - Gary E Martin
- Process and Analytical Chemistry, NMR Structure Elucidation, Merck Research Laboratories, Rahway, NJ, 07065, USA
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Troche‐Pesqueira E, Anklin C, Gil RR, Navarro‐Vázquez A. Computer‐Assisted 3D Structure Elucidation of Natural Products using Residual Dipolar Couplings. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201612454] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Clemens Anklin
- Bruker BioSpin Corp. 15 Fortune Dr. Billerica MA 01821 USA
| | - Roberto R. Gil
- Department of Chemistry Carnegie Mellon University 4400 Fifth Ave Pittsburgh PA 15213 USA
| | - Armando Navarro‐Vázquez
- Departamento de Química Fundamental, CCEN Universidade Federal de Pernambuco Brazil
- Departamento de Química Orgánica Universidade de Vigo 36310 Vigo Spain
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39
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Troche‐Pesqueira E, Anklin C, Gil RR, Navarro‐Vázquez A. Computer‐Assisted 3D Structure Elucidation of Natural Products using Residual Dipolar Couplings. Angew Chem Int Ed Engl 2017; 56:3660-3664. [DOI: 10.1002/anie.201612454] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Indexed: 11/06/2022]
Affiliation(s)
| | - Clemens Anklin
- Bruker BioSpin Corp. 15 Fortune Dr. Billerica MA 01821 USA
| | - Roberto R. Gil
- Department of Chemistry Carnegie Mellon University 4400 Fifth Ave Pittsburgh PA 15213 USA
| | - Armando Navarro‐Vázquez
- Departamento de Química Fundamental, CCEN Universidade Federal de Pernambuco Brazil
- Departamento de Química Orgánica Universidade de Vigo 36310 Vigo Spain
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Waratchareeyakul W, Hellemann E, Gil RR, Chantrapromma K, Langat MK, Mulholland DA. Application of Residual Dipolar Couplings and Selective Quantitative NOE to Establish the Structures of Tetranortriterpenoids from Xylocarpus rumphii. JOURNAL OF NATURAL PRODUCTS 2017; 80:391-402. [PMID: 28121439 DOI: 10.1021/acs.jnatprod.6b00906] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Nine triterpenoid derivatives were isolated from the heartwood of Xylocarpus rumphii and were identified as xylorumphiins E (1), C (2), L (3), and M-R (4-9). Compounds 4-9 have a hemiacetal group in the triterpenoid side chain, making them impossible to purify. Purification was achieved after acetylation and subsequent separation of the epimeric mixtures of acetates; however differentiaition of the R and S epimers was not possible using standard NMR techniques. In one case, the relative configuration of a remotely located stereocenter with respect to the stereocenters in the main skeleton was unambiguously determined using residual dipolar couplings. Dipolar couplings were collected from the sample oriented in compressed poly(methyl methacrylate) gels swollen in CDCl3. In another case, the relative configuration was determined using 1D selective quantitative NOE experiments. Xylorumphiin K (10), xyloccensin E, taraxer-14-en-3β-ol, (22S)-hydroxytirucalla-7,24-diene-3,23-dione, and 25-hydroxy-(20S,24S)-epoxydammaran-3-one were isolated from the bark of the same plant. Compounds 3-10 are new compounds. Compounds 1-6 and xyloccensin E were tested at one concentration, 1 × 10-5 M, in the NCI59 cell one-dose screen but did not show significant activity.
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Affiliation(s)
- Watcharee Waratchareeyakul
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford GU2 7XH, U.K
- Department of Chemistry, Faculty of Science and Technology, Rambhai Barni Rajabhat University , Chanthaburi 22000, Thailand
| | - Erich Hellemann
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Kan Chantrapromma
- Faculty of Science and Technology, Hatyai University , Songkhla 90110, Thailand
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford GU2 7XH, U.K
- School of Chemistry and Physics, University of KwaZulu-Natal , Durban 4041, South Africa
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford GU2 7XH, U.K
- School of Chemistry and Physics, University of KwaZulu-Natal , Durban 4041, South Africa
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41
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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
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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.
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Affiliation(s)
- Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
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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
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Merchak N, Silvestre V, Rouger L, Giraudeau P, Rizk T, Bejjani J, Akoka S. Precise and rapid isotopomic analysis by (1)H-(13)C 2D NMR: Application to triacylglycerol matrices. Talanta 2016; 156-157:239-244. [PMID: 27260459 DOI: 10.1016/j.talanta.2016.05.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/09/2016] [Accepted: 05/11/2016] [Indexed: 10/21/2022]
Abstract
An optimized HSQC sequence was tested and applied to triacylglycerol matrices to determine their isotopic and metabolomic profiles. Spectral aliasing and non-uniform sampling approaches were used to decrease the experimental time and to improve the resolution, respectively. An excellent long-term repeatability of signal integrals was achieved enabling to perform isotopic measurements. Thirty-two commercial vegetable oils were analyzed by this methodology. The results show that this method can be used to classify oil samples according to their geographical and botanical origins.
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Affiliation(s)
- Noelle Merchak
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France; Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of Science, Saint-Joseph University, P.O. Box 11-514 Riad el Solh, Beirut 1107 2050, Lebanon
| | - Virginie Silvestre
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France
| | - Laetitia Rouger
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France
| | - Patrick Giraudeau
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France; Institut Universitaire de France, 1 rue Descartes, 75005 Paris, France
| | - Toufic Rizk
- Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of Science, Saint-Joseph University, P.O. Box 11-514 Riad el Solh, Beirut 1107 2050, Lebanon
| | - Joseph Bejjani
- Research Unit: Technologies et Valorisation Agroalimentaire (TVA), Laboratory of Metrology and Isotopic Fractionation, Faculty of Science, Saint-Joseph University, P.O. Box 11-514 Riad el Solh, Beirut 1107 2050, Lebanon.
| | - Serge Akoka
- EBSI team, Interdisciplinary Chemistry: Synthesis, Analysis, Modelling (CEISAM), University of Nantes-CNRS UMR 6230, 2 rue de la Houssinière, BP 92208, F-44322 Nantes cedex 3, France
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Saurí J, Liu Y, Williamson RT, Martin GE. Observation of potentially troublesome (2) JCC correlations in 1,1-ADEQUATE spectra. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2016; 54:341-345. [PMID: 26845240 DOI: 10.1002/mrc.4385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 10/24/2015] [Indexed: 06/05/2023]
Abstract
Despite the tremendous usage of HMBC to establish long-range (1) H-(13) C and (1) H-(15) N heteronuclear correlations, an inherent drawback of the experiment is the indeterminate nature of the (n) JXH correlations afforded by the experiment. A priori there is no reliable way of determining whether a given (n) JCH correlation is, for example, via two-, three-, or sometimes even four-bonds. This limitation of the HMBC experiment spurred the development of the ADEQUATE family of NMR experiments that rely on, in the case of 1,1-ADEQUATE, an out-and-back transfer of magnetization via the (1) JCC homonuclear coupling constant, which is significantly larger than (n) JCC (where n = 2-4) couplings in most cases. Hence, the 1,1-ADEQUATE experiment has generally been assumed to unequivocally provide the equivalent of (2) JCH correlations. The recent development of the 1,1- and 1,n-HD-ADEQUATE experiments that can provide homodecoupling for certain (1) JCC and (n) JCC correlations has increased the sensitivity of the ADEQUATE experiments significantly and can allow acquisition of these data in a fraction of the time required for the original iterations of this pulse sequence. With these gains in sensitivity, however, there occasionally come unanticipated consequences. We have observed that the collapse of proton multiplets, in addition to providing better s/n for the desired (1) JCC correlations can facilitate the observation of typically weaker (2) JCC correlations across intervening carbonyl resonances in 1,1-HD-ADEQUATE spectra. Several examples are shown, with the results supported by the measurement of the (2) JCC coupling constants in question using J-modulated-HD-ADEQUATE and DFT calculations. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Josep Saurí
- NMR Structure Elucidation, Process and Analytical Chemistry, Merck & Company, Rahway, NJ, 07065, USA
| | - Yizhou Liu
- NMR Structure Elucidation, Process and Analytical Chemistry, Merck & Company, Rahway, NJ, 07065, USA
| | - R Thomas Williamson
- NMR Structure Elucidation, Process and Analytical Chemistry, Merck & Company, Rahway, NJ, 07065, USA
| | - Gary E Martin
- NMR Structure Elucidation, Process and Analytical Chemistry, Merck & Company, Rahway, NJ, 07065, USA
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46
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Hansmann S, Larem née Montag T, Thiele CM. Enantiodifferentiating Properties of the Alignment Media PELG and PBLG - A Comparison. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501410] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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47
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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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48
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Gil-Silva LF, Santamaría-Fernández R, Navarro-Vázquez A, Gil RR. Collection of NMR Scalar and Residual Dipolar Couplings Using a Single Experiment. Chemistry 2015; 22:472-6. [DOI: 10.1002/chem.201503449] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Indexed: 11/11/2022]
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49
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Xie LG, Bagutski V, Audisio D, Wolf LM, Schmidts V, Hofmann K, Wirtz C, Thiel W, Thiele CM, Maulide N. Dynamic behaviour of monohaptoallylpalladium species: internal coordination as a driving force in allylic alkylation chemistry. Chem Sci 2015; 6:5734-5739. [PMID: 29910865 PMCID: PMC5975841 DOI: 10.1039/c5sc01867f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 07/03/2015] [Indexed: 12/12/2022] Open
Abstract
Contemporary catalytic procedures involving alkylpalladium(ii) have enriched the arsenal of synthetic organic chemistry. Those transformations usually rely on internal coordination through "directing groups", carefully designed to maximize catalytic efficiency and regioselectivity. Herein, we report structural and reactivity studies of a series of internally coordinated monohaptoallylpalladium complexes. These species enable the direct spectroscopic observation and theoretical study of π-σ-π interconversion processes. They further display unusual dynamic behavior which should be of direct relevance to chemistries beyond catalytic allylic alkylation.
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Affiliation(s)
- Lan-Gui Xie
- University of Vienna , Institute of Organic Chemistry , Währinger Strasse 38 , 1090 Vienna , Austria .
| | - Viktor Bagutski
- Technische Universität Darmstadt , Clemens Schöpf Institut für Organische Chemie und Biochemie , Alarich-Weiss-Str. 4 , 64287 Darmstadt , Germany .
| | - Davide Audisio
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| | - Larry M Wolf
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| | - Volker Schmidts
- Technische Universität Darmstadt , Clemens Schöpf Institut für Organische Chemie und Biochemie , Alarich-Weiss-Str. 4 , 64287 Darmstadt , Germany .
| | - Kathrin Hofmann
- Technische Universität Darmstadt , Eduard-Zintl-Institute , Alarich-Weiss-Str. 12 , 64287 Darmstadt , Germany
| | - Cornelia Wirtz
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany
| | - Christina M Thiele
- Technische Universität Darmstadt , Clemens Schöpf Institut für Organische Chemie und Biochemie , Alarich-Weiss-Str. 4 , 64287 Darmstadt , Germany .
| | - Nuno Maulide
- University of Vienna , Institute of Organic Chemistry , Währinger Strasse 38 , 1090 Vienna , Austria .
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50
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Riveira MJ, Trigo-Mouriño P, Troche-Pesqueira E, Martin GE, Navarro-Vázquez A, Mischne MP, Gil RR. Self-Sensitized Photooxygenation of 2H-Pyrans: Characterization of Unexpected Products Assisted by Computed Structural Elucidation and Residual Dipolar Couplings. J Org Chem 2015; 80:7396-402. [DOI: 10.1021/acs.joc.5b00817] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Martín J. Riveira
- Instituto
de Química Rosario, Facultad de Ciencias Bioquímicas
y Farmacéuticas, Universidad Nacional de Rosario-CONICET, Suipacha
531, S2002LRK Rosario, Argentina
| | - Pablo Trigo-Mouriño
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Eduardo Troche-Pesqueira
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Departamento
de Química Orgánica, Edificio de Ciencias Experimentais, Universidade de Vigo,
Campus Universitario, 36310 Vigo, Spain
| | - Gary E. Martin
- NMR Structure Elucidation, Process & Analytical Chemistry, Merck Research Laboratories, Rahway, New Jersey 07065, United States
| | - Armando Navarro-Vázquez
- Departamento
de Química Fundamental, Universidade Federal de Pernambuco, Cidade Universitária,
CEP 50.740-540 Recife, Pernambuco, Brazil
| | - Mirta P. Mischne
- Instituto
de Química Rosario, Facultad de Ciencias Bioquímicas
y Farmacéuticas, Universidad Nacional de Rosario-CONICET, Suipacha
531, S2002LRK Rosario, Argentina
| | - Roberto R. Gil
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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