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Sternberg U, Tichotová MC, Tučková L, Ešnerová A, Hanus J, Baszczyňski O, Procházková E. Extending molecular dynamics with dipolar NMR tensors as constraints to chiral phosphorus compounds. Phys Chem Chem Phys 2024; 26:20814-20819. [PMID: 39044477 DOI: 10.1039/d4cp02401j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Molecular dynamics with orientational constraints (MDOC) simulations use NMR parameters as tensorial constraints in the stereochemical analysis of small molecules. 13C-31P Residual dipolar couplings-aided MDOC simulations of small phosphorus molecules determined the relative configurations of rigid molecules after including 3JH-H-couplings as additional constraints. However, flexible molecules remain a problem.
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Affiliation(s)
- Ulrich Sternberg
- COSMOS-Software, 07743 Jena, Germany
- Karlsruhe Institute of Technology (KIT), Postfach 3640, D-76021 Karlsruhe, Germany
| | - Markéta Christou Tichotová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 166 10, Czech Republic.
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Prague 128 43, Czech Republic
| | - Lucie Tučková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 166 10, Czech Republic.
| | - Aneta Ešnerová
- Department of Organic Chemistry, Faculty of Science, Charles University, Prague 128 43, Czech Republic
| | - Jan Hanus
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 166 10, Czech Republic.
| | - Ondřej Baszczyňski
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 166 10, Czech Republic.
- Department of Organic Chemistry, Faculty of Science, Charles University, Prague 128 43, Czech Republic
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 166 10, Czech Republic.
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2
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Tichotová MC, Tučková L, Kocek H, Růžička A, Straka M, Procházková E. Exploring the impact of alignment media on RDC analysis of phosphorus-containing compounds: a molecular docking approach. Phys Chem Chem Phys 2024; 26:2016-2024. [PMID: 38126374 DOI: 10.1039/d3cp04099b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Residual dipolar couplings (RDCs) are employed in NMR analysis when conventional methods, such as J-couplings and nuclear Overhauser effects (NOEs) fail. Low-energy (optimized) conformers are often used as input structures in RDC analysis programs. However, these low-energy structures do not necessarily resemble conformations found in anisotropic environments due to interactions with the alignment medium, especially if the analyte molecules are flexible. Considering interactions with alignment media in RDC analysis, we developed and evaluated a molecular docking-based approach to generate more accurate conformer ensembles for compounds in the presence of the poly-γ-benzyl-L-glutamate alignment medium. We designed chiral phosphorus-containing compounds that enabled us to utilize 31P NMR parameters for the stereochemical analysis. Using P3D/PALES software to evaluate diastereomer discrimination, we found that our conformer ensembles outperform moderately the standard, low-energy conformers in RDC analysis. To further improve our results, we (i) averaged the experimental values of the molecular docking-based conformers by applying the Boltzmann distribution and (ii) optimized the structures through normal mode relaxation, thereby enhancing the Pearson correlation factor R and even diastereomer discrimination in some cases. Nevertheless, we presume that significant differences between J-couplings in isotropic and in anisotropic environments may preclude RDC measurements for flexible molecules. Therefore, generating conformer ensembles based on molecular docking enhances RDC analysis for mildly flexible systems while flexible molecules may require applying more advanced approaches, in particular approaches including dynamical effects.
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Affiliation(s)
- Markéta Christou Tichotová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic.
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 116 28 Prague, Czech Republic
| | - Lucie Tučková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic.
| | - Hugo Kocek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic.
| | - Aleš Růžička
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Pardubice 532 10, Czech Republic
| | - Michal Straka
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic.
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic.
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Structures Controlled by Entropy: The Flexibility of Strychnine as Example. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27227987. [PMID: 36432085 PMCID: PMC9692940 DOI: 10.3390/molecules27227987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/09/2022] [Accepted: 11/11/2022] [Indexed: 11/19/2022]
Abstract
To study the flexibility of strychnine, we performed molecular dynamics simulations with orientational tensorial constraints (MDOC). Tensorial constraints are derived from nuclear magnetic resonance (NMR) interaction tensors, for instance, from residual dipolar couplings (RDCs). Used as orientational constraints, they rotate the whole molecule and molecular parts with low rotational barriers. Since the NMR parameters are measured at ambient temperatures, orientational constraints generate conformers that populate the whole landscape of Gibbs free energy. In MDOC, structures are populated that are not only controlled by energy but by the entropy term TΔS of the Gibbs free energy. In the case of strychnine, it is shown that ring conformers are populated, which has not been discussed in former investigations. These conformer populations are not only in accordance with RDCs but fulfill nuclear Overhauser effect (NOE)-derived distance constraints and 3JHH couplings as well.
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Immel S, Köck M, Reggelin M. NMR-Based Configurational Assignments of Natural Products: How Floating Chirality Distance Geometry Calculations Simplify Gambling with 2 N-1 Diastereomers. JOURNAL OF NATURAL PRODUCTS 2022; 85:1837-1849. [PMID: 35820115 DOI: 10.1021/acs.jnatprod.2c00427] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Using NMR data, the assignment of the correct 3D configuration and conformation to unknown natural products is of pivotal importance in pharmaceutical and medicinal chemistry. In this report, we quantify the probability of configurational assignments to judge the quality of structural elucidations using Bayesian inference in combination with floating-chirality distance geometry simulations. Based on reference-free NOE/ROE data, residual dipolar couplings (RDCs), and residual quadrupolar couplings (RQCs) in various combinations, we demonstrate how the relative configurations of three natural compounds, namely, jatrohemiketal (1), artemisinin (2), and Taxol (3), can be unambiguously established without the necessity to carry out time-consuming DFT-based configurational and conformational analyses. Our results quantitatively describe how reliably molecular geometries can be inferred from experimental NMR data, thereby unequivocally unveiling remaining assignment ambiguities. The methodology presented here will dramatically reduce the risk of incorrect structural assignments based on the overinterpretation of incomplete data and DFT-based structure models in chemistry.
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Affiliation(s)
- Stefan Immel
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
| | - Matthias Köck
- Alfred-Wegener-Institut für Polar- und Meeresforschung in der Helmholtz-Gemeinschaft, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Michael Reggelin
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
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Li XL, Ru T, Navarro-Vázquez A, Lindemann P, Nazaré M, Li XW, Guo YW, Sun H. Weizhouochrones: Gorgonian-Derived Symmetric Dimers and Their Structure Elucidation Using Anisotropic NMR Combined with DP4+ Probability and CASE-3D. JOURNAL OF NATURAL PRODUCTS 2022; 85:1730-1737. [PMID: 35792821 DOI: 10.1021/acs.jnatprod.2c00257] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Natural product dimers have intriguing structural features and often have remarkable pharmacological activities. We report here two uncommon marine gorgonian-derived symmetric dimers, weizhouochrones A (1) and B (2), with indenone-derived monomers, that were isolated from the coral Anthogorgia ochracea collected from the South China Sea. These dimers are difficult targets for structure elucidation that solely relies upon conventional NMR data such as NOEs and J-couplings. Here, to explore the application of emerging methods on the structure elucidation of challenging molecules, we explored a number of different anisotropic and computational NMR approaches. The measurements of anisotropic NMR parameters of weizhouochrone A, including residual dipolar couplings (RDCs) and residual chemical shift anisotropy (RCSA), allowed us to successfully determine the planar structure and its relative configuration. This result was corroborated by a computational NMR analysis based on DP4+ probability and computer-assisted 3D structure elucidation (CASE-3D).
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Affiliation(s)
- Xiao-Lu Li
- Group of Structural Chemistry and Computational Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin 13125, Germany
| | - Tong Ru
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing 100049, China
| | - Armando Navarro-Vázquez
- Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
| | - Peter Lindemann
- Group of Medicinal Chemistry, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin 13125, Germany
| | - Marc Nazaré
- Group of Medicinal Chemistry, Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin 13125, Germany
| | - Xu-Wen Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing 100049, China
| | - Yue-Wei Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
- University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing 100049, China
| | - Han Sun
- Institute of Chemistry, Technical University of Berlin, Berlin 10623, Germany
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6
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Sternberg U, Farès C. Statistical evaluation of simulated NMR data of flexible molecules. Phys Chem Chem Phys 2022; 24:9608-9618. [PMID: 35403649 DOI: 10.1039/d2cp00330a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new probability score-named χ-probability-is introduced for evaluating the fit of mixed NMR datasets to calculate molecular model ensembles, in order to answer challenging structural questions such as the determination of stereochemical configurations. Similar to the DP4 parameter, the χ-probability is based on Bayes theorem and expresses the probability that an experimental NMR dataset fits to a given individual within a finite set of candidate structures or configurations. Here, the χ-probability is applied to single out the correct configuration in four example cases, with increasing complexity and conformational mobility. The NMR data (which include RDCs, NOE distances and 3J couplings) are calculated from MDOC (Molecular Dynamics with Orientational Constraints) trajectories and are investigated against experimentally measured data. It is demonstrated that this approach singles out the correct stereochemical configuration with probabilities more than 98%, even for highly mobile molecules. In more demanding cases, a decisive χ-probability test requires that the datasets include high-quality NOE distances in addition to RDC values.
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Affiliation(s)
- Ulrich Sternberg
- Research Partner of Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany. .,COSMOS-Software, Jena, Germany
| | - Christophe Farès
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany.
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7
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Immel S, Köck M, Reggelin M. Bayesian Inference Applied to NMR-Based Configurational Assignments by Floating Chirality Distance Geometry Calculations. J Am Chem Soc 2022; 144:6830-6838. [PMID: 35412312 DOI: 10.1021/jacs.2c00813] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using NMR data, the assignment of the correct 3D configuration and conformation to unknown natural products is of pivotal importance in pharmaceutical and medicinal chemistry. In this report, we quantify the quality and probability of structural elucidations using Bayesian inference in combination with floating chirality distance geometry simulations. Here, we will discuss the configurational analysis of three complex natural products including isopinocampheol (1), plakilactone H (2), and iodocallophycoic acid A (3) using NMR restraints of various types and in different combinations (residual dipolar couplings (RDCs) and NOE-derived distances). Our results quantitatively demonstrate how reliably molecular geometries can be inferred from experimental NMR data, unequivocally unveiling remaining assignment ambiguities. The methodology presented here can dramatically reduce the risk of incorrect structural assignments based on the overinterpretation of incomplete data in chemistry.
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Affiliation(s)
- Stefan Immel
- Clemens Schöpf Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
| | - Matthias Köck
- Alfred-Wegener-Institut für Polar- and Meeresforschung in der Helmholtz-Gemeinschaft, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Michael Reggelin
- Clemens Schöpf Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
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Tichotová M, Ešnerová A, Tučková L, Bednárová L, Císařová I, Baszczyňski O, Procházková E. 31P NMR parameters may facilitate the stereochemical analysis of phosphorus-containing compounds. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 336:107149. [PMID: 35121491 DOI: 10.1016/j.jmr.2022.107149] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/19/2022] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Conventional Nuclear Magnetic Resonance (NMR) analysis relies on H-H/C-H interactions. However, these interactions are sometimes insufficient for an accurate and precise NMR analysis. In this study, we show that 31P NMR parameters can provide critical structural insights into the stereochemistry of phosphorus-containing compounds. For this purpose, we prepared a set of model phosphorus-based proline derivatives, separated diastereoisomers, and determined their absolute configuration by single-crystal X-ray diffraction. After supplementing these results by electronic circular dichroism (ECD) spectroscopy, we combined experimental data and DFT calculations from our model compounds to perform a detailed conformational analysis, thereby determining their relative configuration. Overall, our findings establish an experimental paradigm for combining 31P NMR spectroscopy with other optical methods to facilitate the stereochemical analysis of phosphorus-containing compounds.
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Affiliation(s)
- Markéta Tichotová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic; Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 116 28 Prague, Czech Republic
| | - Aneta Ešnerová
- Department of Organic Chemistry, Faculty of Science, Charles University, 116 28 Prague, Czech Republic
| | - Lucie Tučková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic
| | - Lucie Bednárová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry, Faculty of Science, Charles University, 116 28 Prague, Czech Republic
| | - Ondřej Baszczyňski
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic; Department of Organic Chemistry, Faculty of Science, Charles University, 116 28 Prague, Czech Republic
| | - Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 160 00 Prague, Czech Republic.
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9
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Berdagué P, Gouilleux B, Noll M, Immel S, Reggelin M, Lesot P. Study and quantification of enantiodiscrimination power of four polymeric chiral LLCs using NAD 2D-NMR. Phys Chem Chem Phys 2022; 24:7338-7348. [DOI: 10.1039/d1cp04915a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Identifying and understanding the role of key molecular factors involved in the orientation/discrimination phenomena of analytes in polymer-based chiral liquid crystals (CLCs) are essential tasks for optimizing computational predictions (molecular...
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Aroulanda C, Lesot P. Molecular enantiodiscrimination by NMR spectroscopy in chiral oriented systems: Concept, tools, and applications. Chirality 2021; 34:182-244. [PMID: 34936130 DOI: 10.1002/chir.23386] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/20/2021] [Accepted: 10/15/2021] [Indexed: 11/06/2022]
Abstract
The study of enantiodiscriminations in relation to various facets of enantiomorphism (chirality/prochirality) and/or molecular symmetry is an exciting area of modern organic chemistry and an ongoing challenge for nuclear magnetic resonance (NMR) spectroscopists who have developed many useful analytical approaches to solve stereochemical problems. Among them, the anisotropic NMR using chiral aligning solvents has provided a set of new and original tools by making accessible all intramolecular, order-dependent NMR interactions (anisotropic interactions), such as residual chemical shift anisotropy (RCSA), residual dipolar coupling (RDC), and residual quadrupolar coupling (RQC) for spin I > 1/2, while preserving high spectral resolution. The force of NMR in enantiopure, oriented solvents lies on its ability to orient differently in average on the NMR timescale enantiomers of chiral molecules and enantiotopic elements of prochiral ones, leading distinct NMR spectra or signals to be detected. In this compendium mainly written for all chemists playing with (pro)chirality, we overview various key aspects of NMR in weakly aligning chiral solvents as the lyotropic liquid crystals (LLCs), in particular those developed in France to study (pro)chiral compounds in relation with chemists needs: study of enantiopurity of mixture, stereochemistry, natural isotopic fractionation, as well as molecular conformation and configuration. Key representative examples covering the diversity of enantiomorphism concept, and the main and most recent applications illustrating the analytical potential of this NMR in polypeptide-based chiral liquid crystals (CLCs) are examined. The latest analytical strategy developed to determine in-solution conformational distribution of flexibles solutes using NMR in polypeptide-based aligned solvents is also proposed.
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Affiliation(s)
- Christie Aroulanda
- RMN en Milieu Orienté, ICMMO, UMR CNRS 8182, Université Paris-Saclay, Orsay cedex, France
| | - Philippe Lesot
- RMN en Milieu Orienté, ICMMO, UMR CNRS 8182, Université Paris-Saclay, Orsay cedex, France
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Immel S, Köck M, Reggelin M. NMR-Based Configurational Assignments of Natural Products: Gibbs Sampling and Bayesian Inference Using Floating Chirality Distance Geometry Calculations. Mar Drugs 2021; 20:14. [PMID: 35049868 PMCID: PMC8781118 DOI: 10.3390/md20010014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/12/2021] [Accepted: 12/20/2021] [Indexed: 02/07/2023] Open
Abstract
Floating chirality restrained distance geometry (fc-rDG) calculations are used to directly evolve structures from NMR data such as NOE-derived intramolecular distances or anisotropic residual dipolar couplings (RDCs). In contrast to evaluating pre-calculated structures against NMR restraints, multiple configurations (diastereomers) and conformations are generated automatically within the experimental limits. In this report, we show that the "unphysical" rDG pseudo energies defined from NMR violations bear statistical significance, which allows assigning probabilities to configurational assignments made that are fully compatible with the method of Bayesian inference. These "diastereomeric differentiabilities" then even become almost independent of the actual values of the force constants used to model the restraints originating from NOE or RDC data.
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Affiliation(s)
- Stefan Immel
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
| | - Matthias Köck
- Alfred-Wegener-Institut für Polar-und Meeresforschung in der Helmholtz-Gemeinschaft, Am Handelshafen 12, 27570 Bremerhaven, Germany;
| | - Michael Reggelin
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
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12
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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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13
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Sager E, Tzvetkova P, Gossert AD, Piechon P, Luy B. Determination of Configuration and Conformation of a Reserpine Derivative with Seven Stereogenic Centers Using Molecular Dynamics with RDC-Derived Tensorial Constraints*. Chemistry 2020; 26:14435-14444. [PMID: 32744785 PMCID: PMC7702126 DOI: 10.1002/chem.202002642] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/22/2020] [Indexed: 11/11/2022]
Abstract
NMR-based determination of the configuration of complex molecules containing many stereocenters is often not possible using traditional NOE data and coupling patterns. Making use of residual dipolar couplings (RDCs), we were able to determine the relative configuration of a natural product containing seven stereocenters, including a chiral amine lacking direct RDC data. To identify the correct relative configuration out of 32 possible ones, experimental RDCs were used in three different approaches for data interpretation: by fitting experimental data based singular value decomposition (SVD) using a single alignment tensor and either (i) a single conformer or (ii) multiple conformers, or alternatively (iii) using molecular dynamics simulations with tensorial orientational constraints (MDOC). Even though in all three approaches one and the same configuration could be selected and clear discrimination between possible configurations was achieved, the experimental data was not fully satisfied by the methods based on single tensor approaches. While these two approaches are faster, only MDOC is able to fully reproduce experimental results, as the obtained conformational ensemble adequately covers the conformational space necessary to describe the molecule with inherent flexibility.
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Affiliation(s)
- Emine Sager
- Institut für Organische ChemieKarlsruher Institut für Technologie (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
- Novartis Pharma AGNovartis Institutes for Biomedical Research4002BaselSwitzerland
| | - Pavleta Tzvetkova
- Institut für Biologische Grenzflächen 4—Magnetische ResonanzKarlsruher Institut für Technologie (KIT)Postfach 364076021KarlsruheGermany
| | - Alvar D. Gossert
- Novartis Pharma AGNovartis Institutes for Biomedical Research4002BaselSwitzerland
- Institut für Molekularbiologie und BiophysikETH Zürich8093ZürichSwitzerland
| | - Philippe Piechon
- Novartis Pharma AGNovartis Institutes for Biomedical Research4002BaselSwitzerland
| | - Burkhard Luy
- Institut für Organische ChemieKarlsruher Institut für Technologie (KIT)Fritz-Haber-Weg 676131KarlsruheGermany
- Institut für Biologische Grenzflächen 4—Magnetische ResonanzKarlsruher Institut für Technologie (KIT)Postfach 364076021KarlsruheGermany
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14
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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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15
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Sternberg U, Tzvetkova P, Muhle-Goll C. The simulation of NMR data of flexible molecules: sagittamide A as an example for MD simulations with orientational constraints. Phys Chem Chem Phys 2020; 22:17375-17384. [PMID: 32705098 DOI: 10.1039/d0cp01905d] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The recently developed MDOC (Molecular Dynamics with Orientational Constraints) simulation is applied for the first time to a fully flexible molecule. MDOC simulations aim to single out the naturally existing configuration of molecules and to elucidate conformer populations. The performance of the method was first demonstrated on a well-studied test case, the five-membered ring lactone (α-methylene-γ-butyrolactone). In the case of sagittamide A, one-bond 1H-13C residual dipolar couplings (RDC) are used as orientational constraints that reorient the molecule or parts of it. In addition, NOE distances and 3J scalar couplings are used as constraints. Five possible configurations of sagittamide A (labelled a to e) are considered. One experimental RDC value per flexible unit was available and this was not sufficient to single out one valid configuration. The problem could be solved by including NOE distances as well as 3J couplings as complementary constraints into the MDOC simulations. In accordance with former investigations, we confirmed the configuration a for the natural product. A detailed analysis of conformers of the central chain of 6 chiral carbon atoms could be given by inspecting the MDOC trajectory. The relative abundance of these conformers is crucial in fulfilling all three sets of constraints.
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Affiliation(s)
- Ulrich Sternberg
- Research Partner of Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany. and COSMOS-Software, Jena, Germany
| | - Pavleta Tzvetkova
- Institute of Biological Interfaces 4, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Claudia Muhle-Goll
- Institute of Biological Interfaces 4, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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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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Conformational Investigations in Flexible Molecules Using Orientational NMR Constraints in Combination with 3J-Couplings and NOE Distances. Molecules 2019; 24:molecules24234417. [PMID: 31816930 PMCID: PMC6930577 DOI: 10.3390/molecules24234417] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/21/2019] [Accepted: 11/26/2019] [Indexed: 12/19/2022] Open
Abstract
The downscaling of NMR tensorial interactions, such as dipolar couplings, from tens of kilohertz to a few hertz in low-order media is the result of dynamics spanning several orders of magnitudes, including vibrational modes (~ns-fs), whole-molecule reorientation (~ns) and higher barrier internal conformational exchange (<ms). In this work, we propose to employ these dynamically averaged interactions to drive an “alignment-tensor-free” molecular dynamic simulation with orientation constraints (MDOC) in order to efficiently access the conformational space sampled by flexible small molecules such as natural products. Key to this approach is the application of tensorial pseudo-force restraints which simultaneously guide the overall reorientation and conformational fluctuations based on defined memory function over the running trajectory. With the molecular mechanics force-field, which includes bond polarization theory (BPT), and complemented with other available NMR parameters such as NOEs and scalar J-couplings, MDOC efficiently arrives at dynamic ensembles that reproduce the entire NMR dataset with exquisite accuracy and theoretically reveal the systems conformational space and equilibrium. The method as well as its potential towards configurational elucidation is presented on diastereomeric pairs of flexible molecules: a small 1,4-diketone 1 with a single rotatable bond as well as a 24-ring macrolide related to the natural product mandelalide A 2.
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