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Sajed T, Sayeeda Z, Lee BL, Berjanskii M, Wang F, Gautam V, Wishart DS. Accurate Prediction of 1H NMR Chemical Shifts of Small Molecules Using Machine Learning. Metabolites 2024; 14:290. [PMID: 38786767 PMCID: PMC11123270 DOI: 10.3390/metabo14050290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024] Open
Abstract
NMR is widely considered the gold standard for organic compound structure determination. As such, NMR is routinely used in organic compound identification, drug metabolite characterization, natural product discovery, and the deconvolution of metabolite mixtures in biofluids (metabolomics and exposomics). In many cases, compound identification by NMR is achieved by matching measured NMR spectra to experimentally collected NMR spectral reference libraries. Unfortunately, the number of available experimental NMR reference spectra, especially for metabolomics, medical diagnostics, or drug-related studies, is quite small. This experimental gap could be filled by predicting NMR chemical shifts for known compounds using computational methods such as machine learning (ML). Here, we describe how a deep learning algorithm that is trained on a high-quality, "solvent-aware" experimental dataset can be used to predict 1H chemical shifts more accurately than any other known method. The new program, called PROSPRE (PROton Shift PREdictor) can accurately (mean absolute error of <0.10 ppm) predict 1H chemical shifts in water (at neutral pH), chloroform, dimethyl sulfoxide, and methanol from a user-submitted chemical structure. PROSPRE (pronounced "prosper") has also been used to predict 1H chemical shifts for >600,000 molecules in many popular metabolomic, drug, and natural product databases.
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Affiliation(s)
- Tanvir Sajed
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Zinat Sayeeda
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Brian L. Lee
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Mark Berjanskii
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Fei Wang
- Department of Computing Science, University of Alberta, Edmonton, AB T6G 2E8, Canada
| | - Vasuk Gautam
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - David S. Wishart
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
- Department of Computing Science, University of Alberta, Edmonton, AB T6G 2E8, Canada
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2B7, Canada
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB T6G 2H7, Canada
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Sainju D, Lucas R, Le Gresley A. Evaluation of nuclear magnetic resonance spectroscopy for characterisation and quantitation of water-soluble polymers in river water. WATER RESEARCH 2023; 245:120650. [PMID: 37742403 DOI: 10.1016/j.watres.2023.120650] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/14/2023] [Accepted: 09/18/2023] [Indexed: 09/26/2023]
Abstract
Water-soluble polymers (WSPs) are commonly used in industrial, commercial, agricultural and pharmaceutical products and their molecular weights and concentrations vary considerably. Methods commonly used in the analysis of WSPs are often for pure products or formulations with only a few other high MW constituents. These methods, like size exclusion chromatography (SEC) or Gel Permeation Chromatography coupled with Mass Spectrometry (MS) can be frustrated by the impact of the necessary separation steps prior to identification and the limitations of MS when identifying and quantifying polymers. To that end, the employment of a Nuclear Magnetic Resonance (NMR) method to identify, characterize and quantify WSPs in the real-world is reported for the first time. Samples were taken from fourteen UK inland river sites, concentrated via air-drying, freeze-drying or vacuum-drying and analyzed using 1D 1H NMR and 2D 1H Diffusion Ordered Spectroscopy (DOSY) NMR analysis. Seven of the river sites showed the presence of polyethylene glycol (PEG) with a range of molecular weights, evidencing the application of these techniques in analysis of WSPs. Soil percolation models evidenced the proof of principle that these techniques can also be used for the detection of polyacrylamide (PAM) and polyacrylic acid (PAA). This work should better enable the evaluation of the biological impact of WSPs on aquatic organisms in future studies.
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Affiliation(s)
- Drishna Sainju
- Department of Chemistry and Pharmaceutical Sciences, HSSCE Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK
| | - Robert Lucas
- Consumer Healthcare, Haleon PLC, Weybridge, Surrey, UK
| | - Adam Le Gresley
- Department of Chemistry and Pharmaceutical Sciences, HSSCE Faculty, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK.
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3
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Stadler GR, Segawa TF, Bütikofer M, Decker V, Loss S, Czarniecki B, Torres F, Riek R. Fragment Screening and Fast Micromolar Detection on a Benchtop NMR Spectrometer Boosted by Photoinduced Hyperpolarization. Angew Chem Int Ed Engl 2023; 62:e202308692. [PMID: 37524651 DOI: 10.1002/anie.202308692] [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: 06/20/2023] [Revised: 07/28/2023] [Accepted: 07/31/2023] [Indexed: 08/02/2023]
Abstract
Fragment-based drug design is a well-established strategy for rational drug design, with nuclear magnetic resonance (NMR) on high-field spectrometers as the method of reference for screening and hit validation. However, high-field NMR spectrometers are not only expensive, but require specialized maintenance, dedicated space, and depend on liquid helium cooling which became critical over the recurring global helium shortages. We propose an alternative to high-field NMR screening by applying the recently developed approach of fragment screening by photoinduced hyperpolarized NMR on a cryogen-free 80 MHz benchtop NMR spectrometer yielding signal enhancements of up to three orders in magnitude. It is demonstrated that it is possible to discover new hits and kick-off drug design using a benchtop NMR spectrometer at low micromolar concentrations of both protein and ligand. The approach presented performs at higher speed than state-of-the-art high-field NMR approaches while exhibiting a limit of detection in the nanomolar range. Photoinduced hyperpolarization is known to be inexpensive and simple to be implemented, which aligns greatly with the philosophy of benchtop NMR spectrometers. These findings open the way for the use of benchtop NMR in near-physiological conditions for drug design and further life science applications.
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Affiliation(s)
- Gabriela R Stadler
- ETH Zürich, Swiss Federal Institute of Technology, Institute for Molecular Physical Science, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Takuya F Segawa
- ETH Zürich, Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Matthias Bütikofer
- ETH Zürich, Swiss Federal Institute of Technology, Institute for Molecular Physical Science, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Venita Decker
- Bruker BioSpin GmbH, Rudolf-Plank-Strasse 23, 76275, Ettlingen, Germany
| | - Sandra Loss
- Bruker Switzerland AG, Industriestrasse 26, 8117, Fällanden, Switzerland
| | - Barbara Czarniecki
- Bruker Switzerland AG, Industriestrasse 26, 8117, Fällanden, Switzerland
| | - Felix Torres
- ETH Zürich, Swiss Federal Institute of Technology, Institute for Molecular Physical Science, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
- NexMR GmbH, Wiesenstrasse 10 A, 8952, Schlieren, Switzerland
| | - Roland Riek
- ETH Zürich, Swiss Federal Institute of Technology, Institute for Molecular Physical Science, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
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4
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Moxley-Paquette V, Lane D, Steiner K, Downey K, Costa PM, Lysak DH, Ronda K, Soong R, Zverev D, De Castro P, Frei T, Stuessi J, Al Adwan-Stojilkovic D, Graf S, Gloor S, Schmidig D, Kuemmerle R, Kuehn T, Busse F, Utz M, Lacerda A, Nashman B, Albert L, Anders J, Simpson AJ. Development of Low-Magnetic Susceptibility Microcoils via 5-Axis Machining for Analysis of Biological and Environmental Samples. Anal Chem 2023; 95:13932-13940. [PMID: 37676066 DOI: 10.1021/acs.analchem.3c02437] [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: 09/08/2023]
Abstract
In environmental research, it is critical to understand how toxins impact invertebrate eggs and egg banks, which, due to their tiny size, are very challenging to study by conventional nuclear magnetic resonance (NMR) spectroscopy. Microcoil technology has been extensively utilized to enhance the mass-sensitivity of NMR. In a previous study, 5-axis computer numerical control (CNC) micromilling (shown to be a viable alternative to traditional microcoil production methods) was used to create a prototype copper slotted-tube resonator (STR). Despite the excellent limit of detection (LOD) of the resonator, the quality of the line shape was very poor due to the magnetic susceptibility of the copper resonator itself. This is best solved using magnetic susceptibility-matched materials. In this study, approaches are investigated that improve the susceptibility while retaining the versatility of coil milling. One method involves machining STRs from various copper/aluminum alloys, while the other involves machining ones from an aluminum 2011 alloy and electroplating them with copper. In all cases, combining copper and aluminum to produce resonators resulted in improved line shape and SNR compared to pure copper resonators due to their reduced magnetic susceptibility. However, the copper-plated aluminum resonators showed optimal performance from the devices tested. The enhanced LOD of these STRs allowed for the first 1H-13C heteronuclear multiple quantum coherence (HMQC) of a single intact 13C-labeled Daphnia magna egg (∼4 μg total biomass). This is a key step toward future screening programs that aim to elucidate the toxic processes in aquatic eggs.
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Affiliation(s)
- Vincent Moxley-Paquette
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Daniel Lane
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Katrina Steiner
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Katelyn Downey
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Peter M Costa
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Daniel H Lysak
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Kiera Ronda
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Ronald Soong
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Dimitri Zverev
- NSCNC Manufacturing LTD, 1515 Broadway Street Unit 607, Port Coquitlam, British Columbia V3C 6M2, Canada
| | - Peter De Castro
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Thomas Frei
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Juerg Stuessi
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | | | - Stephan Graf
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Simon Gloor
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Daniel Schmidig
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Rainer Kuemmerle
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Till Kuehn
- Bruker BioSpin AG, Industriestrasse 26, 8117 Fällanden, Switzerland
| | - Falko Busse
- Bruker Biospin GmbH, Silberstreifen 4, 76287 Rheinstetten, Germany
| | - Marcel Utz
- School of Chemistry, University of Southampton, Southampton SO17 1BJ, U.K
| | - Andressa Lacerda
- Synex Medical, 2 Bloor Street E, Suite 310, Toronto, Ontario M4W 1A8Canada
| | - Ben Nashman
- Synex Medical, 2 Bloor Street E, Suite 310, Toronto, Ontario M4W 1A8Canada
| | - Larry Albert
- ACI Alloys, Inc, 1458 Seareel Place, San Jose, California 95131, United States
| | - Jens Anders
- Institute of Smart Sensors,University of Stuttgart, Pfaffenwaldring 47, 70569 Stuttgart, Germany
| | - André J Simpson
- Environmental NMR Center, University of Toronto, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
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Lysak DH, Grisi M, Marable K, Conley GM, Michal CA, Moxley-Paquette V, Wolff WW, Downey K, Kock FVC, Costa PM, Ronda K, Moraes TB, Steiner K, Colnago LA, Simpson AJ. Exploring the Potential of Broadband Complementary Metal Oxide Semiconductor Micro-Coil Nuclear Magnetic Resonance for Environmental Research. Molecules 2023; 28:5080. [PMID: 37446742 PMCID: PMC10343494 DOI: 10.3390/molecules28135080] [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: 06/01/2023] [Revised: 06/23/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
With sensitivity being the Achilles' heel of nuclear magnetic resonance (NMR), the superior mass sensitivity offered by micro-coils can be an excellent choice for tiny, mass limited samples such as eggs and small organisms. Recently, complementary metal oxide semiconductor (CMOS)-based micro-coil transceivers have been reported and demonstrate excellent mass sensitivity. However, the ability of broadband CMOS micro-coils to study heteronuclei has yet to be investigated, and here their potential is explored within the lens of environmental research. Eleven nuclei including 7Li, 19F, 31P and, 205Tl were studied and detection limits in the low to mid picomole range were found for an extended experiment. Further, two environmentally relevant samples (a sprouting broccoli seed and a D. magna egg) were successfully studied using the CMOS micro-coil system. 13C NMR was used to help resolve broad signals in the 1H spectrum of the 13C enriched broccoli seed, and steady state free precession was used to improve the signal-to-noise ratio by a factor of six. 19F NMR was used to track fluorinated contaminants in a single D. magna egg, showing potential for studying egg-pollutant interactions. Overall, CMOS micro-coil NMR demonstrates significant promise in environmental research, especially when the future potential to scale to multiple coil arrays (greatly improving throughput) is considered.
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Affiliation(s)
- Daniel H. Lysak
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Marco Grisi
- Annaida Technologies, Innovation Park, 1015 Lausanne, Switzerland
| | - Kathryn Marable
- Annaida Technologies, Innovation Park, 1015 Lausanne, Switzerland
| | | | - Carl A. Michal
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | | | - William W. Wolff
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Katelyn Downey
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Flavio V. C. Kock
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Peter M. Costa
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Kiera Ronda
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Tiago B. Moraes
- Departamento Engenharia de Biossistemas, Universidade de São Paulo/ESALQ, Av. Páduas Dias, 11, Piracicaba 13418-900, SP, Brazil
| | - Katrina Steiner
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
| | - Luiz A. Colnago
- Embrapa Instrumentação, Rua XV de Novembro 1452, São Carlos 13560-970, SP, Brazil
| | - Andre J. Simpson
- Environmental NMR Centre, University of Toronto, Toronto, ON M1C 1A4, Canada
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Lysak DH, Kock FVC, Mamone S, Soong R, Glöggler S, Simpson AJ. In vivo singlet state filtered nuclear magnetic resonance: towards monitoring toxic responses inside living organisms. Chem Sci 2023; 14:1413-1418. [PMID: 36794179 PMCID: PMC9906653 DOI: 10.1039/d2sc06624f] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 01/06/2023] [Indexed: 01/11/2023] Open
Abstract
In line with recent paradigm shifts in toxicity testing, in vivo nuclear magnetic resonance (NMR) is a powerful tool for studying the biological impacts and perturbations caused by toxicants in living organisms. However, despite the excellent molecular insights that can be obtained through this technique, in vivo NMR applications are hampered by considerable experimental challenges such as poor line shape and spectral overlap. Here, we demonstrate the application of singlet-filtered NMR to target specific metabolites and facilitate the study of metabolite fluxes in living Daphnia magna, an aquatic keystone species and model organism. Informed by mathematical simulations and experiments on ex vivo organisms, singlet state NMR is used to monitor the flux of metabolites such as d-glucose and serine in living D. magna, during the environmentally relevant processes of anoxic stress and reduced food availability. Overall, singlet state NMR is shown to have significant future potential for studying metabolic processes in vivo.
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Affiliation(s)
- Daniel H. Lysak
- Environmental NMR Centre, University of Toronto Scarborough1265 Military TrailScarboroughOntarioCanada
| | - Flavio V. C. Kock
- Environmental NMR Centre, University of Toronto Scarborough1265 Military TrailScarboroughOntarioCanada,Department of Chemistry, Federal University of São Carlos (UFSCar)Rod. Washington Luís, MonjolinhoSão Carlos–SP13565-905Brazil
| | - Salvatore Mamone
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences Am Fassberg 11 37077 Göttingen Germany
| | - Ronald Soong
- Environmental NMR Centre, University of Toronto Scarborough1265 Military TrailScarboroughOntarioCanada
| | - Stefan Glöggler
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences Am Fassberg 11 37077 Göttingen Germany
| | - Andre J. Simpson
- NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary SciencesAm Fassberg11 37077GöttingenGermany
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Theillet FX, Luchinat E. In-cell NMR: Why and how? PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 132-133:1-112. [PMID: 36496255 DOI: 10.1016/j.pnmrs.2022.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/19/2022] [Accepted: 04/27/2022] [Indexed: 06/17/2023]
Abstract
NMR spectroscopy has been applied to cells and tissues analysis since its beginnings, as early as 1950. We have attempted to gather here in a didactic fashion the broad diversity of data and ideas that emerged from NMR investigations on living cells. Covering a large proportion of the periodic table, NMR spectroscopy permits scrutiny of a great variety of atomic nuclei in all living organisms non-invasively. It has thus provided quantitative information on cellular atoms and their chemical environment, dynamics, or interactions. We will show that NMR studies have generated valuable knowledge on a vast array of cellular molecules and events, from water, salts, metabolites, cell walls, proteins, nucleic acids, drugs and drug targets, to pH, redox equilibria and chemical reactions. The characterization of such a multitude of objects at the atomic scale has thus shaped our mental representation of cellular life at multiple levels, together with major techniques like mass-spectrometry or microscopies. NMR studies on cells has accompanied the developments of MRI and metabolomics, and various subfields have flourished, coined with appealing names: fluxomics, foodomics, MRI and MRS (i.e. imaging and localized spectroscopy of living tissues, respectively), whole-cell NMR, on-cell ligand-based NMR, systems NMR, cellular structural biology, in-cell NMR… All these have not grown separately, but rather by reinforcing each other like a braided trunk. Hence, we try here to provide an analytical account of a large ensemble of intricately linked approaches, whose integration has been and will be key to their success. We present extensive overviews, firstly on the various types of information provided by NMR in a cellular environment (the "why", oriented towards a broad readership), and secondly on the employed NMR techniques and setups (the "how", where we discuss the past, current and future methods). Each subsection is constructed as a historical anthology, showing how the intrinsic properties of NMR spectroscopy and its developments structured the accessible knowledge on cellular phenomena. Using this systematic approach, we sought i) to make this review accessible to the broadest audience and ii) to highlight some early techniques that may find renewed interest. Finally, we present a brief discussion on what may be potential and desirable developments in the context of integrative studies in biology.
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Affiliation(s)
- Francois-Xavier Theillet
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
| | - Enrico Luchinat
- Dipartimento di Scienze e Tecnologie Agro-Alimentari, Alma Mater Studiorum - Università di Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; CERM - Magnetic Resonance Center, and Neurofarba Department, Università degli Studi di Firenze, 50019 Sesto Fiorentino, Italy
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Smith AJR, York R, Uhrín D, Bell NGA. 19F-centred NMR analysis of mono-fluorinated compounds. RSC Adv 2022; 12:10062-10070. [PMID: 35424946 PMCID: PMC8966657 DOI: 10.1039/d1ra08046f] [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: 11/02/2021] [Accepted: 03/15/2022] [Indexed: 11/29/2022] Open
Abstract
Addressing limitations of the existing NMR techniques for the structure determination of mono-fluorinated compounds, we have developed methodology that uses 19F as the focal point of this process. The proposed 19F-centred NMR analysis consists of a complementary set of broadband, phase-sensitive NMR experiments that utilise the substantial sensitivity of 19F and its far reaching couplings with 1H and 13C to obtain a large number of NMR parameters. The assembled 1H, 13C and 19F chemical shifts, values of J HF, J HH, and J FC coupling constants and the size of 13C induced 19F isotopic shifts constitute a rich source of information that enables structure elucidation of fluorinated moieties and even complete structures of molecules. Here we introduce the methodology, provide a detailed description of each NMR experiment and illustrate their interpretation using 3-fluoro-3-deoxy-d-glucose. This novel approach performs particularly well in the structure elucidation of fluorinated compounds embedded in complex mixtures, eliminating the need for compound separation or use of standards to confirm the structures. It represents a major contribution towards the analysis of fluorinated agrochemicals and (radio)pharmaceuticals at any point during their lifetime, including preparation, use, biotransformation and biodegradation in the environment. The developed methodology can also assist with the investigations of the stability of fluoroorganics and their pharmacokinetics. Studies of reaction mechanisms using fluorinated molecules as convenient reporters of these processes, will also benefit.
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Affiliation(s)
- Alan J R Smith
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Rd Edinburgh EH9 3FJ UK
| | - Richard York
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Rd Edinburgh EH9 3FJ UK
| | - Dušan Uhrín
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Rd Edinburgh EH9 3FJ UK
| | - Nicholle G A Bell
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Rd Edinburgh EH9 3FJ UK
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