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Bånkestad M, Dorst KM, Widmalm G, Rönnols J. Carbohydrate NMR chemical shift prediction by GeqShift employing E(3) equivariant graph neural networks. RSC Adv 2024; 14:26585-26595. [PMID: 39175672 PMCID: PMC11340439 DOI: 10.1039/d4ra03428g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 08/02/2024] [Indexed: 08/24/2024] Open
Abstract
Carbohydrates, vital components of biological systems, are well-known for their structural diversity. Nuclear Magnetic Resonance (NMR) spectroscopy plays a crucial role in understanding their intricate molecular arrangements and is essential in assessing and verifying the molecular structure of organic molecules. An important part of this process is to predict the NMR chemical shift from the molecular structure. This work introduces a novel approach that leverages E(3) equivariant graph neural networks to predict carbohydrate NMR spectral data. Notably, our model achieves a substantial reduction in mean absolute error, up to threefold, compared to traditional models that rely solely on two-dimensional molecular structure. Even with limited data, the model excels, highlighting its robustness and generalization capabilities. The model is dubbed GeqShift (geometric equivariant shift) and uses equivariant graph self-attention layers to learn about NMR chemical shifts, in particular since stereochemical arrangements in carbohydrate molecules are characteristics of their structures.
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Affiliation(s)
- Maria Bånkestad
- Department of Information Technology, Uppsala University Sweden
- RISE Research Institutes of Sweden Stockholm Sweden
| | - Kevin M Dorst
- Department of Organic Chemistry, Stockholm University Sweden
| | - Göran Widmalm
- Department of Organic Chemistry, Stockholm University Sweden
| | - Jerk Rönnols
- RISE Research Institutes of Sweden Stockholm Sweden
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2
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Kurfiřt M, Hamala V, Beránek J, Červenková Šťastná L, Červený J, Dračínský M, Bernášková J, Spiwok V, Bosáková Z, Bojarová P, Karban J. Synthesis and unexpected binding of monofluorinated N,N'-diacetylchitobiose and LacdiNAc to wheat germ agglutinin. Bioorg Chem 2024; 147:107395. [PMID: 38705105 DOI: 10.1016/j.bioorg.2024.107395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/15/2024] [Accepted: 04/23/2024] [Indexed: 05/07/2024]
Abstract
Fluorination of carbohydrate ligands of lectins is a useful approach to examine their binding profile, improve their metabolic stability and lipophilicity, and convert them into 19F NMR-active probes. However, monofluorination of monovalent carbohydrate ligands often leads to a decreased or completely lost affinity. By chemical glycosylation, we synthesized the full series of methyl β-glycosides of N,N'-diacetylchitobiose (GlcNAcβ(1-4)GlcNAcβ1-OMe) and LacdiNAc (GalNAcβ(1-4)GlcNAcβ1-OMe) systematically monofluorinated at all hydroxyl positions. A competitive enzyme-linked lectin assay revealed that the fluorination at the 6'-position of chitobioside resulted in an unprecedented increase in affinity to wheat germ agglutinin (WGA) by one order of magnitude. For the first time, we have characterized the binding profile of a previously underexplored WGA ligand LacdiNAc. Surprisingly, 4'-fluoro-LacdiNAc bound WGA even stronger than unmodified LacdiNAc. These observations were interpreted using molecular dynamic calculations along with STD and transferred NOESY NMR techniques, which gave evidence for the strengthening of CH/π interactions after deoxyfluorination of the side chain of the non-reducing GlcNAc. These results highlight the potential of fluorinated glycomimetics as high-affinity ligands of lectins and 19F NMR-active probes.
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Affiliation(s)
- Martin Kurfiřt
- Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 1/135, CZ-165 00 Praha 6, Czech Republic; University of Chemistry and Technology, Technická 5, CZ-166 28 Praha 6, Czech Republic
| | - Vojtěch Hamala
- Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 1/135, CZ-165 00 Praha 6, Czech Republic; University of Chemistry and Technology, Technická 5, CZ-166 28 Praha 6, Czech Republic
| | - Jan Beránek
- University of Chemistry and Technology, Technická 5, CZ-166 28 Praha 6, Czech Republic
| | - Lucie Červenková Šťastná
- Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 1/135, CZ-165 00 Praha 6, Czech Republic
| | - Jakub Červený
- Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, CZ-142 00 Praha 4, Czech Republic; Department of Analytical Chemistry, Faculty of Science, Charles University in Prague, Hlavova 8, CZ-128 43 Praha 2, Czech Republic
| | - Martin Dračínský
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo Náměstí 542/2, CZ-160 00 Praha 6, Czech Republic
| | - Jana Bernášková
- Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 1/135, CZ-165 00 Praha 6, Czech Republic
| | - Vojtěch Spiwok
- University of Chemistry and Technology, Technická 5, CZ-166 28 Praha 6, Czech Republic
| | - Zuzana Bosáková
- Department of Analytical Chemistry, Faculty of Science, Charles University in Prague, Hlavova 8, CZ-128 43 Praha 2, Czech Republic
| | - Pavla Bojarová
- Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, CZ-142 00 Praha 4, Czech Republic
| | - Jindřich Karban
- Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 1/135, CZ-165 00 Praha 6, Czech Republic.
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3
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Santana OL, Silva DG, Santana SR. Solvate Suite: A Command-Line Interface for Molecular Simulations and Multiscale Microsolvation Modeling. J Chem Inf Model 2024; 64:3767-3778. [PMID: 38621228 DOI: 10.1021/acs.jcim.3c01899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
In this work, we introduce the Solvate Suite, a comprehensive and modular command-line interface designed for molecular simulation and microsolvation modeling. The suite interfaces with widely used scientific software, streamlining computational experiments for liquid systems through the automated creation of simulation boxes and topology with adjustable simulation parameters. Furthermore, it has features for graphical and statistical analysis of simulated properties and extraction of trajectory configurations with various filters. Additionally, it introduces innovative strategies for microsolvation modeling with a multiscale approach, employing equilibrated dynamics to identify favorable solute-solvent interactions and enabling full cluster optimization for free-energy calculations without imaginary frequency contamination.
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Affiliation(s)
- Otávio L Santana
- Chemistry Department, Federal University of Paraíba, João Pessoa, Paraíba 58051-900, Brazil
| | - Daniel G Silva
- Chemistry Department, Federal University of Paraíba, João Pessoa, Paraíba 58051-900, Brazil
| | - Sidney R Santana
- Chemistry and Physics Department, Federal University of Paraíba, Areia, Paraíba 58397-000, Brazil
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4
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Venetos M, Elkin M, Delaney C, Hartwig JF, Persson KA. Deconvolution and Analysis of the 1H NMR Spectra of Crude Reaction Mixtures. J Chem Inf Model 2024; 64:3008-3020. [PMID: 38573053 PMCID: PMC11040730 DOI: 10.1021/acs.jcim.3c01864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 04/05/2024]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is an important analytical technique in synthetic organic chemistry, but its integration into high-throughput experimentation workflows has been limited by the necessity of manually analyzing the NMR spectra of new chemical entities. Current efforts to automate the analysis of NMR spectra rely on comparisons to databases of reported spectra for known compounds and, therefore, are incompatible with the exploration of new chemical space. By reframing the NMR spectrum of a reaction mixture as a joint probability distribution, we have used Hamiltonian Monte Carlo Markov Chain and density functional theory to fit the predicted NMR spectra to those of crude reaction mixtures. This approach enables the deconvolution and analysis of the spectra of mixtures of compounds without relying on reported spectra. The utility of our approach to analyze crude reaction mixtures is demonstrated with the experimental spectra of reactions that generate a mixture of isomers, such as Wittig olefination and C-H functionalization reactions. The correct identification of compounds in a reaction mixture and their relative concentrations is achieved with a mean absolute error as low as 1%.
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Affiliation(s)
- Maxwell
C. Venetos
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
| | - Masha Elkin
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Connor Delaney
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - John F. Hartwig
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kristin A. Persson
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
- Molecular
Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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5
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Platzer G, Ptaszek AL, Böttcher J, Fuchs JE, Geist L, Braun D, McConnell DB, Konrat R, Sánchez-Murcia PA, Mayer M. Ligand 1 H NMR Chemical Shifts as Accurate Reporters for Protein-Ligand Binding Interfaces in Solution. Chemphyschem 2024; 25:e202300636. [PMID: 37955910 DOI: 10.1002/cphc.202300636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/23/2023] [Indexed: 11/14/2023]
Abstract
The availability of high-resolution 3D structural information is crucial for investigating guest-host systems across a wide range of fields. In the context of drug discovery, the information is routinely used to establish and validate structure-activity relationships, grow initial hits from screening campaigns, and to guide molecular docking. For the generation of protein-ligand complex structural information, X-ray crystallography is the experimental method of choice, however, with limited information on protein flexibility. An experimentally verified structural model of the binding interface in the native solution-state would support medicinal chemists in their molecular design decisions. Here we demonstrate that protein-bound ligand 1 H NMR chemical shifts are highly sensitive and accurate probes for the immediate chemical environment of protein-ligand interfaces. By comparing the experimental ligand 1 H chemical shift values with those computed from the X-ray structure using quantum mechanics methodology, we identify significant disagreements for parts of the ligand between the two experimental techniques. We show that quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) ensembles can be used to refine initial X-ray co-crystal structures resulting in a better agreement with experimental 1 H ligand chemical shift values. Overall, our findings highlight the usefulness of ligand 1 H NMR chemical shift information in combination with a QM/MM MD workflow for generating protein-ligand ensembles that accurately reproduce solution structural data.
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Affiliation(s)
- Gerald Platzer
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Campus Vienna Biocenter 5, 1030-, Vienna, Austria
- MAG-LAB GmbH, Karl-Farkas-Gasse 22, 1030-, Vienna, Austria
| | - Aleksandra L Ptaszek
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Campus Vienna Biocenter 5, 1030-, Vienna, Austria
- Laboratory for Computer-Aided Molecular Design, Division of Medicinal Chemistry, Otto Loewi Research Center, Medical University Graz, Neue Stiftingtalstrasse 6/III, 8010-, Graz, Austria
| | - Jark Böttcher
- Boehringer Ingelheim RCV GmbH & Co. KG, Dr. Boehringer Gasse 5-11, 1121-, Vienna, Austria
| | - Julian E Fuchs
- Boehringer Ingelheim RCV GmbH & Co. KG, Dr. Boehringer Gasse 5-11, 1121-, Vienna, Austria
| | - Leonhard Geist
- Boehringer Ingelheim RCV GmbH & Co. KG, Dr. Boehringer Gasse 5-11, 1121-, Vienna, Austria
| | - Daniel Braun
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Campus Vienna Biocenter 5, 1030-, Vienna, Austria
| | - Darryl B McConnell
- Boehringer Ingelheim RCV GmbH & Co. KG, Dr. Boehringer Gasse 5-11, 1121-, Vienna, Austria
| | - Robert Konrat
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Campus Vienna Biocenter 5, 1030-, Vienna, Austria
| | - Pedro A Sánchez-Murcia
- Laboratory for Computer-Aided Molecular Design, Division of Medicinal Chemistry, Otto Loewi Research Center, Medical University Graz, Neue Stiftingtalstrasse 6/III, 8010-, Graz, Austria
| | - Moriz Mayer
- Boehringer Ingelheim RCV GmbH & Co. KG, Dr. Boehringer Gasse 5-11, 1121-, Vienna, Austria
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Choutka J, Parkan K, Pohl R, Kaminský J. On the origin of the electronic and magnetic circular dichroism of naphthyl C-glycosides: Anomeric configuration. Carbohydr Res 2024; 535:109021. [PMID: 38171193 DOI: 10.1016/j.carres.2023.109021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/21/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024]
Abstract
Aryl C-glycosides, in which the glycosidic bond is changed to a carbon-carbon bond, are an important family of biologically-active compounds. They often serve as secondary metabolites or exhibit antibiotic and cytostatic activities. Their stability to hydrolysis has made them attractive targets for new drugs. Their conformational behavior often strongly influences the resulting function. Their detailed structural and conformational description is thus highly desirable. This work studies the structure of three different naphthyl C-glycosides using UV-vis absorption as well as electronic and magnetic circular dichroism. It also describes their conformational preferences using a combination of molecular dynamics and DFT calculations. The reliability of these preferences has been verified by simulations of spectral properties and a comparison with their measured spectra. In particular, ECD spectroscopy has been shown to distinguish easily between α- and β-pseudoanomers of aryl C-glycosides. Computer simulations and spectral decomposition have revealed how the resulting ECD patterns of the naphthyl glycosides studied are influenced by different conformer populations. In conclusion, reliable ECD patterns cannot be calculated by separating the naphthyl rotation from other conformational motions. MCD patterns have been similar for all the naphthyl C-glycosides studied. No clear diagnostic features have been found for either the pseudoanomeric configuration or the preferred hydroxymethyl rotamer. Nevertheless, the work has demonstrated the potential of MCD for the study of aryl glycosides interacting with proteins.
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Affiliation(s)
- Jan Choutka
- Institute of Organic Chemistry and Biochemistry AS CR, Flemingovo nám. 2, 160 00, Prague, Czech Republic
| | - Kamil Parkan
- Institute of Organic Chemistry and Biochemistry AS CR, Flemingovo nám. 2, 160 00, Prague, Czech Republic; Department of Chemistry of Natural Compounds, University of Chemistry and Technology Prague, Technická 5, 166 28, Prague, Czech Republic
| | - Radek Pohl
- Institute of Organic Chemistry and Biochemistry AS CR, Flemingovo nám. 2, 160 00, Prague, Czech Republic
| | - Jakub Kaminský
- Institute of Organic Chemistry and Biochemistry AS CR, Flemingovo nám. 2, 160 00, Prague, Czech Republic.
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7
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Matveevskaya VV, Pavlov DI, Kovrizhina AR, Sukhikh TS, Sadykov EH, Dorovatovskii PV, Lazarenko VA, Khlebnikov AI, Potapov AS. Experimental and Computational Investigation of the Oxime Bond Stereochemistry in c-Jun N-terminal Kinase 3 Inhibitors 11 H-Indeno[1,2- b]quinoxalin-11-one Oxime and Tryptanthrin-6-oxime. Pharmaceutics 2023; 15:1802. [PMID: 37513989 PMCID: PMC10383563 DOI: 10.3390/pharmaceutics15071802] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/16/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
11H-Indeno[1,2-b]quinoxalin-11-one oxime (IQ-1) and tryptanthrin-6-oxime are potent c-Jun N-terminal kinase 3 (JNK-3) inhibitors demonstrating neuroprotective, anti-inflammatory and anti-arthritic activity. However, the stereochemical configuration of the oxime carbon-nitrogen double bond (E- or Z-) in these compounds was so far unknown. In this contribution, we report the results of the determination of the double bond configuration in the solid state by single crystal X-ray diffraction and in solution by 1D and 2D NMR techniques and DFT calculations. It was found that both in the solid state and in solution, IQ-1 adopts the E-configuration stabilized by intermolecular hydrogen bonds, in contrast to previously assumed Z-configuration that could be stabilized only by an intramolecular hydrogen bond.
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Affiliation(s)
- Vladislava V Matveevskaya
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Lavrentiev Ave., 630090 Novosibirsk, Russia
| | - Dmitry I Pavlov
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Lavrentiev Ave., 630090 Novosibirsk, Russia
| | - Anastasia R Kovrizhina
- Kizhner Research Center, National Research Tomsk Polytechnic University, 30 Lenin Ave., 634050 Tomsk, Russia
| | - Taisiya S Sukhikh
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Lavrentiev Ave., 630090 Novosibirsk, Russia
| | - Evgeniy H Sadykov
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Lavrentiev Ave., 630090 Novosibirsk, Russia
| | - Pavel V Dorovatovskii
- National Research Centre "Kurchatov Institute", Kurchatov Square 1, 123182 Moscow, Russia
| | - Vladimir A Lazarenko
- National Research Centre "Kurchatov Institute", Kurchatov Square 1, 123182 Moscow, Russia
| | - Andrei I Khlebnikov
- Kizhner Research Center, National Research Tomsk Polytechnic University, 30 Lenin Ave., 634050 Tomsk, Russia
| | - Andrei S Potapov
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Lavrentiev Ave., 630090 Novosibirsk, Russia
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Cohen RD, Wood JS, Lam YH, Buevich AV, Sherer EC, Reibarkh M, Williamson RT, Martin GE. DELTA50: A Highly Accurate Database of Experimental 1H and 13C NMR Chemical Shifts Applied to DFT Benchmarking. Molecules 2023; 28:molecules28062449. [PMID: 36985422 PMCID: PMC10051451 DOI: 10.3390/molecules28062449] [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: 01/25/2023] [Revised: 02/23/2023] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
Density functional theory (DFT) benchmark studies of 1H and 13C NMR chemical shifts often yield differing conclusions, likely due to non-optimal test molecules and non-standardized data acquisition. To address this issue, we carefully selected and measured 1H and 13C NMR chemical shifts for 50 structurally diverse small organic molecules containing atoms from only the first two rows of the periodic table. Our NMR dataset, DELTA50, was used to calculate linear scaling factors and to evaluate the accuracy of 73 density functionals, 40 basis sets, 3 solvent models, and 3 gauge-referencing schemes. The best performing DFT methodologies for 1H and 13C NMR chemical shift predictions were WP04/6-311++G(2d,p) and ωB97X-D/def2-SVP, respectively, when combined with the polarizable continuum solvent model (PCM) and gauge-independent atomic orbital (GIAO) method. Geometries should be optimized at the B3LYP-D3/6-311G(d,p) level including the PCM solvent model for the best accuracy. Predictions of 20 organic compounds and natural products from a separate probe set had root-mean-square deviations (RMSD) of 0.07 to 0.19 for 1H and 0.5 to 2.9 for 13C. Maximum deviations were less than 0.5 and 6.5 ppm for 1H and 13C, respectively.
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Affiliation(s)
- Ryan D Cohen
- Analytical Research and Development, Merck & Co., Inc., Rahway, NJ 07065, USA
- Department of Chemistry and Biochemistry, Seton Hall University, South Orange, NJ 07079, USA
| | - Jared S Wood
- Analytical Research and Development, Merck & Co., Inc., Rahway, NJ 07065, USA
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington, Wilmington, NC 28409, USA
| | - Yu-Hong Lam
- Department of Computational and Structural Chemistry, Merck & Co., Inc., Rahway, NJ 07065, USA
| | - Alexei V Buevich
- Analytical Research and Development, Merck & Co., Inc., Rahway, NJ 07065, USA
| | - Edward C Sherer
- Analytical Research and Development, Merck & Co., Inc., Rahway, NJ 07065, USA
| | - Mikhail Reibarkh
- Analytical Research and Development, Merck & Co., Inc., Rahway, NJ 07065, USA
| | - R Thomas Williamson
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington, Wilmington, NC 28409, USA
| | - Gary E Martin
- Department of Chemistry and Biochemistry, Seton Hall University, South Orange, NJ 07079, USA
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9
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Imamura K, Yokogawa D, Higashi M, Sato H. Reference interaction site model self-consistent field with constrained spatial electron density approach for nuclear magnetic shielding in solution. J Chem Phys 2022; 157:204105. [DOI: 10.1063/5.0122326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We propose a new hybrid approach combining quantum chemistry and statistical mechanics of liquids for calculating the nuclear magnetic resonance (NMR) chemical shifts of solvated molecules. Based on the reference interaction site model self-consistent field with constrained spatial electron density distribution (RISM–SCF–cSED) method, the electronic structure of molecules in solution is obtained, and the expression for the nuclear magnetic shielding tensor is derived as the second-order derivative of the Helmholtz energy of the solution system. We implemented a method for calculating chemical shifts and applied it to an adenine molecule in water, where hydrogen bonding plays a crucial role in electronic and solvation structures. We also performed the calculations of 17O chemical shifts, which showed remarkable solvent dependence. While converged results could not be sometimes obtained using the conventional method, in the present framework with RISM–SCF–cSED, an adequate representation of electron density is guaranteed, making it possible to obtain an NMR shielding constant stably. This introduction of cSED is key to extending the method’s applicability to obtain the chemical shift of various chemical species. The present demonstration illustrates our approach’s superiority in terms of numerical robustness and accuracy.
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Affiliation(s)
- Kosuke Imamura
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Daisuke Yokogawa
- Graduate School of Arts and Science, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Masahiro Higashi
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Hirofumi Sato
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
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