1
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Taylor R, Swift T, Wilkinson D, Afarinkia K. A method for estimation of plasma protein binding using diffusion ordered NMR spectroscopy (DOSY). RSC Med Chem 2024; 15:2372-2379. [PMID: 39026647 PMCID: PMC11253862 DOI: 10.1039/d4md00244j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 06/06/2024] [Indexed: 07/20/2024] Open
Abstract
The plasma protein binding (PPB) of a drug plays a key role in both its pharmacokinetic and pharmacodynamic properties. During lead optimisation, medium and high throughput methods for the early determination of PPB can provide important information about potential PKPD profile within a chemotype or between different chemotype series. Diffusion ordered spectroscopy (DOSY) is an NMR spectroscopic technique that measures the diffusion of a molecule through the magnetic field gradient, according to its molecular size/weight. Here, we describe the use of DOSY for a rapid and straightforward method to evaluate the PPB of drug molecules, using their binding to bovine serum albumin (BSA) as a model.
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Affiliation(s)
- Rachel Taylor
- Institute of Cancer Therapeutics, University of Bradford Richmond Road BD7 1DP UK
| | - Thomas Swift
- Polymer and Biomaterials Laboratories, School of Chemistry and Bioscience, University of Bradford Richmond Road BD7 1DP UK
| | | | - Kamyar Afarinkia
- Institute of Cancer Therapeutics, University of Bradford Richmond Road BD7 1DP UK
- School of Medicine and Biosciences, University of West London Saint Mary's Road London W5 5RF UK
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2
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Pagano K, De Rosa L, Tomaselli S, Molinari H, D'Andrea LD, Ragona L. Characterizing the Oligomers Distribution along the Aggregation Pathway of Amyloid Aβ1-40 by NMR. Chemistry 2024; 30:e202400594. [PMID: 38712990 DOI: 10.1002/chem.202400594] [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: 02/13/2024] [Revised: 05/06/2024] [Accepted: 05/07/2024] [Indexed: 05/08/2024]
Abstract
This study delves into the early aggregation process of the Aβ1-40 amyloid peptide, elucidating the associated oligomers distribution. Motivated by the acknowledged role of small oligomers in the neurotoxic damage linked to Alzheimer's disease, we present an experimental protocol for preparing 26-O-acyl isoAβ1-40, a modified Aβ1-40 peptide facilitating rapid isomerization to the native amide form at neutral pH. This ensures seed-free solutions, minimizing experimental variability. Additionally, we demonstrate the efficacy of coupling NMR diffusion ordered spectroscopy (DOSY) with the Inverse Laplace Transform (ILT) reconstruction method, for effective characterization of early aggregation processes. This innovative approach efficiently maps oligomers distributions across a wide spectrum of initial peptide concentrations offering unique insights into the evolution of oligomers relative populations. As a proof of concept, we demonstrate the efficacy of our approach assessing the impact of Epigallocathechin gallate, a known remodeling agent of amyloid fibrils, on the oligomeric distributions of aggregated Aβ1-40. The DOSY-ILT proposed approach stands as a robust and discriminating asset, providing a powerful strategy for rapidly gaining insight into potential inhibitors' impact on the aggregation process.
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Affiliation(s)
- Katiuscia Pagano
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta" CNR, via Alfonso Corti, 12, Milano, Italy
| | - Lucia De Rosa
- Istituto di Biostrutture e Bioimmagini CNR, Via Pietro Castellino 111, Napoli, Italy
| | - Simona Tomaselli
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta" CNR, via Alfonso Corti, 12, Milano, Italy
| | - Henriette Molinari
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta" CNR, via Alfonso Corti, 12, Milano, Italy
| | - Luca Domenico D'Andrea
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta" CNR, Via Mario Bianco, 9, Milano, Italy
| | - Laura Ragona
- Istituto di Scienze e Tecnologie Chimiche "Giulio Natta" CNR, via Alfonso Corti, 12, Milano, Italy
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3
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Qi Y, Ayinla M, Clifford S, Ramström O. Spontaneous and Selective Macrocyclization in Nitroaldol Reaction Systems. J Org Chem 2023. [PMID: 38154053 DOI: 10.1021/acs.joc.3c02148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
Through a dynamic polymerization and self-sorting process, a range of lowellane macrocycles have been efficiently generated in nitroaldol systems composed of aromatic dialdehydes and aliphatic or aromatic dinitroalkanes. All identified macrocycles show a composition of two repeating units, resulting in tetra-β-nitroalcohols of different structures. The effects of the building block structure on the macrocyclization process have been demonstrated, and the influence from the solvent has been explored. In general, the formation of the lowellanes was amplified in response to phase-change effects, although solution-phase structures were, in some cases, favored.
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Affiliation(s)
- Yunchuan Qi
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, Massachusetts 01854, United States
| | - Mubarak Ayinla
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, Massachusetts 01854, United States
| | - Stephen Clifford
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, Massachusetts 01854, United States
| | - Olof Ramström
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, Massachusetts 01854, United States
- Department of Chemistry and Biomedical Sciences, Linnaeus University, SE-39182 Kalmar, Sweden
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4
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Villasana Y, Armenise S, Ábrego J, Atienza-Martínez M, Hablich K, Bimbela F, Cornejo A, Gandía LM. Exploring a Low-Cost Valorization Route for Amazonian Cocoa Pod Husks through Thermochemical and Catalytic Upgrading of Pyrolysis Vapors. ACS OMEGA 2023; 8:37610-37621. [PMID: 37841159 PMCID: PMC10568713 DOI: 10.1021/acsomega.3c06672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 09/18/2023] [Indexed: 10/17/2023]
Abstract
Ecuador as an international leader in the production of cocoa beans produced more than 300 000 tons in 2021; hence, the management and valorization of the 2 MM tons of waste generated annually by this industry have a strategic and socioeconomic value. Consequently, appropriate technologies to avoid environmental problems and promote sustainable development and the bioeconomy, especially considering that this is a megadiverse country, are of the utmost relevance. For this reason, we explored a low-cost pyrolysis route for valorizing cocoa pod husks from Ecuador's Amazonian region, aiming at producing pyrolysis liquids (bio-oil), biochar, and gas as an alternative chemical source from cocoa residues in the absence of hydrogen. Downstream catalytic processing of hot pyrolysis vapors using Mo- and/or Ni-based catalysts and standalone γ-Al2O3 was applied for obtaining upgraded bio-oils in a laboratory-scale fixed bed reactor, at 500 °C in a N2 atmosphere. As a result, bimetallic catalysts increased the bio-oil aqueous phase yield by 6.6%, at the expense of the organic phase due to cracking reactions according to nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS) results. Overall product yield remained constant, in comparison to pyrolysis without any downstream catalytic treatment (bio-oil ∼39.0-40.0 wt % and permanent gases 24.6-26.6 wt %). Ex situ reduced and passivated MoNi/γ-Al2O3 led to the lowest organic phase and highest aqueous phase yields. The product distribution between the two liquid phases was also modified by the catalytic upgrading experiments carried out, according to heteronuclear single-quantum correlation (HSQC), total correlation spectroscopy (TOCSY), and NMR analyses. The detailed composition distribution reported here shows the chemical production potential of this residue and serves as a starting point for subsequent valorizing technologies and/or processes in the food and nonfood industry beneficiating society, environment, economy, and research.
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Affiliation(s)
- Yanet Villasana
- Biomass
Laboratory, Biomass to Resources Group, Universidad Regional Amazónica IKIAM, Tena 150150, Ecuador
| | - Sabino Armenise
- Centro
de Investigación Cepsa, Alcalá de Henares, Av. Punto com, Madrid 28805, Spain
| | - Javier Ábrego
- Grupo
de Procesos Termoquímicos, Instituto Universitario de Investigación
en Ingeniería de Aragón (I3A), Universidad de Zaragoza, Zaragoza 50018, Spain
| | - María Atienza-Martínez
- Grupo
de Procesos Termoquímicos, Instituto Universitario de Investigación
en Ingeniería de Aragón (I3A), Universidad de Zaragoza, Zaragoza 50018, Spain
| | - Karina Hablich
- Grupo
de Reactores Químicos y Procesos para la Valorización
de Recursos Renovables, Institute for Advanced Materials and Mathematics
(InaMat2), Universidad Pública de
Navarra (UPNA), Pamplona 31006, Spain
| | - Fernando Bimbela
- Grupo
de Reactores Químicos y Procesos para la Valorización
de Recursos Renovables, Institute for Advanced Materials and Mathematics
(InaMat2), Universidad Pública de
Navarra (UPNA), Pamplona 31006, Spain
| | - Alfonso Cornejo
- Grupo
de Diseño, Síntesis Evaluación y Optimización
de Nuevas Sustancias de Interés, Institute for Advanced Materials
and Mathematics (InaMat2), Universidad Pública
de Navarra (UPNA), Pamplona E-31006, Spain
| | - Luis M. Gandía
- Grupo
de Reactores Químicos y Procesos para la Valorización
de Recursos Renovables, Institute for Advanced Materials and Mathematics
(InaMat2), Universidad Pública de
Navarra (UPNA), Pamplona 31006, Spain
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5
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Oyagi K, Ogasawara S, Tamiaki H. Intramolecular axial α/β-coordination of the 13 2-terminal pyridyl group to the central zinc atom in chlorophyll- a derivatives. Org Biomol Chem 2022; 20:6339-6350. [PMID: 35815555 DOI: 10.1039/d2ob00903j] [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
Chlorophyll(Chl)-a derivatives possessing a zinc center and a C132-alkanoate residue with a terminal pyridyl group were synthesized. Their C132-epimerically pure products were isolated by preparative reverse phase HPLC. The C132-stereochemistry resulted in two directed terminal pyridinyl groups that coordinate with the central zinc atom in each stereoisomeric molecule: α/β-intramolecular axial coordination. The asymmetric axial coordinations mimic the immobilization manner of Chl-a in photosynthetically active proteins. The diastereomerically dependent conformers in solution were characterized by 1D/2D NMR, UV-visible absorption, and fluorescence emission as well as circular dichroism (CD) spectroscopy. The 1H NMR and DOSY spectra revealed that the stereoselectively intramolecular coordination occurred in less coordinative deuterated chloroform, whereas a highly coordinative deuterated pyridine molecule replaced the terminal pyridine moiety as the axial ligand to form a mixture of α/β-coordinated species. Their optical spectra in pyridine were nearly independent of the C132-stereochemistry and the linkers in the C132-substituents. The CD bands of β-coordinated species in chloroform were more intense than those of the corresponding α-coordinated stereoisomers, indicating that the former had a larger distortion of the chlorin π-plane than the latter. Therefore, the α-coordinated Chl complex is more conformationally stable than the β-complex.
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Affiliation(s)
- Kagari Oyagi
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
| | - Shin Ogasawara
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
| | - Hitoshi Tamiaki
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
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6
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Whitehead RD, Teschke CM, Alexandrescu AT. Pulse-field gradient nuclear magnetic resonance of protein translational diffusion from native to non-native states. Protein Sci 2022; 31:e4321. [PMID: 35481638 PMCID: PMC9047038 DOI: 10.1002/pro.4321] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/31/2022] [Accepted: 04/12/2022] [Indexed: 01/31/2023]
Abstract
Hydrodynamic radii (Rh -values) calculated from diffusion coefficients measured by pulse-field-gradient nuclear magnetic resonance are compared for folded and unfolded proteins. For native globular proteins, the Rh -values increase as a power of 0.35 with molecular size, close to the scaling factor of 0.33 predicted from polymer theory. Unfolded proteins were studied under four sets of conditions: in the absence of denaturants, in the presence of 6 M urea, in 95% dimethyl sulfoxide (DMSO), and in 40% hexafluoroisopropanol (HFIP). Scaling factors under all four unfolding conditions are similar (0.49-0.53) approaching the theoretical value of 0.60 for a fully unfolded random coil. Persistence lengths are also similar, except smaller in 95% DMSO, suggesting that the polypeptides are more disordered on a local scale with this solvent. Three of the proteins in our unfolded set have an asymmetric sequence-distribution of charged residues. While these proteins behave normally in water and 6 M urea, they give atypically low Rh -values in 40% HFIP and 95% DMSO suggesting they are forming electrostatic hairpins, favored by their asymmetric sequence charge distribution and the low dielectric constants of DMSO and HFIP. While diffusion-ordered NMR spectroscopy can separate small molecules, we show a number of factors combine to make protein-sized molecules much more difficult to resolve in mixtures. Finally, we look at the temperature dependence of apparent diffusion coefficients. Small molecules show a linear temperature response, while large proteins show abnormally large apparent diffusion coefficients at high temperatures due to convection, suggesting diffusion reference standards are only useful near 25°C.
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Affiliation(s)
- Richard D Whitehead
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Carolyn M Teschke
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA.,Department of Chemistry, University of Connecticut, Storrs, Connecticut, USA
| | - Andrei T Alexandrescu
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
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7
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Ben-Tal Y, Boaler PJ, Dale HJA, Dooley RE, Fohn NA, Gao Y, García-Domínguez A, Grant KM, Hall AMR, Hayes HLD, Kucharski MM, Wei R, Lloyd-Jones GC. Mechanistic analysis by NMR spectroscopy: A users guide. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 129:28-106. [PMID: 35292133 DOI: 10.1016/j.pnmrs.2022.01.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
A 'principles and practice' tutorial-style review of the application of solution-phase NMR in the analysis of the mechanisms of homogeneous organic and organometallic reactions and processes. This review of 345 references summarises why solution-phase NMR spectroscopy is uniquely effective in such studies, allowing non-destructive, quantitative analysis of a wide range of nuclei common to organic and organometallic reactions, providing exquisite structural detail, and using instrumentation that is routinely available in most chemistry research facilities. The review is in two parts. The first comprises an introduction to general techniques and equipment, and guidelines for their selection and application. Topics include practical aspects of the reaction itself, reaction monitoring techniques, NMR data acquisition and processing, analysis of temporal concentration data, NMR titrations, DOSY, and the use of isotopes. The second part comprises a series of 15 Case Studies, each selected to illustrate specific techniques and approaches discussed in the first part, including in situ NMR (1/2H, 10/11B, 13C, 15N, 19F, 29Si, 31P), kinetic and equilibrium isotope effects, isotope entrainment, isotope shifts, isotopes at natural abundance, scalar coupling, kinetic analysis (VTNA, RPKA, simulation, steady-state), stopped-flow NMR, flow NMR, rapid injection NMR, pure shift NMR, dynamic nuclear polarisation, 1H/19F DOSY NMR, and in situ illumination NMR.
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Affiliation(s)
- Yael Ben-Tal
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Patrick J Boaler
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Harvey J A Dale
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Ruth E Dooley
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom; Evotec (UK) Ltd, 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire OX14 4RZ, United Kingdom
| | - Nicole A Fohn
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Yuan Gao
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Andrés García-Domínguez
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Katie M Grant
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Andrew M R Hall
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Hannah L D Hayes
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Maciej M Kucharski
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Ran Wei
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Guy C Lloyd-Jones
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom.
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8
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In-situ monitoring of cyclic olefin ring-opening metathesis polymerization by Raman spectroscopy: An effective tool for functional polymer and copolymer design. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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9
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Robertson C, Raj N, Lucas R, Coban T, Gresley AL. A proof-of-concept study utilising 2D NMR spectrometry for in situ characterisation and quantitation of key biomarkers and actives in tape stripped ex vivo human skin. Talanta 2022; 237:122980. [PMID: 34736701 DOI: 10.1016/j.talanta.2021.122980] [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: 08/04/2021] [Revised: 10/11/2021] [Accepted: 10/17/2021] [Indexed: 11/17/2022]
Abstract
The development of a semi-automated and rapid analytical technique for dermatological analysis has become a key aim of many medical and commercial entities through greater awareness of people to skin health and its importance in the 21st century. We present a proof-of-concept methodology demonstrating the use of validated non-destructive, in-situ (Nuclear Magnetic Resonance Spectroscopy) NMR techniques for characterisation and quantitation of (Natural Moisturising Factor) NMF compounds and actives from topical formulations. This quantitation is crucial for appropriate diagnosis of atopic dermatitis severity due to its association with reduced NMF abundance. This study is the first to combine diffusion NMR, semi-automated quantitation and ex-vivo skin samples to measure NMF and permeation of actives. We have shown that diffusion NMR allows for resolution between formulation components through determination of self-diffusion coefficients. We also demonstrate how the metabolomics software chenomxtm can be used to identify and quantitate individual NMF components. We show comparable results to previous literature on NMF layers in the skin, alongside reinforcing findings on permeation enhancers and heat effects on transdermal delivery of actives and formulation components. The presented methodology has shown great potential as an effective non-destructive, fast and versatile technique for dermatological analysis of physiology and actives, with future hardware and software developments in NMR making the future of dermatological analysis via NMR very promising.
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Affiliation(s)
- Cameron Robertson
- Department of Chemical and Pharmaceutical Sciences, Faculty of SEC, Kingston University, Kingston-upon-Thames, Surrey, KT1 2EE, UK.
| | - Nidhin Raj
- GlaxoSmithKline Consumer Healthcare, Weybridge, UK
| | - Robert Lucas
- GlaxoSmithKline Consumer Healthcare, Weybridge, UK
| | - Tomris Coban
- Department of Chemical and Pharmaceutical Sciences, Faculty of SEC, Kingston University, Kingston-upon-Thames, Surrey, KT1 2EE, UK
| | - Adam Le Gresley
- Department of Chemical and Pharmaceutical Sciences, Faculty of SEC, Kingston University, Kingston-upon-Thames, Surrey, KT1 2EE, UK
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10
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Di Mola A, Summa FF, Oliva P, Lelj F, Remiddi S, Silvani L, Massa A. Synergistic Properties of Arabinogalactan (AG) and Hyaluronic Acid (HA) Sodium Salt Mixtures. Molecules 2021; 26:7246. [PMID: 34885828 PMCID: PMC8658974 DOI: 10.3390/molecules26237246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 11/24/2021] [Accepted: 11/24/2021] [Indexed: 11/29/2022] Open
Abstract
The properties of mixtures of two polysaccharides, arabinogalactan (AG) and hyaluronic acid (HA), were investigated in solution by the measurement of diffusion coefficients D of water protons by DOSY (Diffusion Ordered SpectroscopY), by the determination of viscosity and by the investigation of the affinity of a small molecule molecular probe versus AG/HA mixtures in the presence of bovine submaxillary mucin (BSM) by 1HNMR spectroscopy. Enhanced mucoadhesive properties, decreased mobility of water and decreased viscosity were observed at the increase of AG/HA ratio and of total concentration of AG. This unusual combination of properties can lead to more effective and long-lasting hydration of certain tissues (inflamed skin, dry eye corneal surface, etc.) and can be useful in the preparation of new formulations of cosmetics and of drug release systems, with the advantage of reducing the viscosity of the solutions.
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Affiliation(s)
- Antonia Di Mola
- Department of Chemistry and Biology, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Italy; (A.D.M.); (F.F.S.); (P.O.)
| | - Francesco Ferdinando Summa
- Department of Chemistry and Biology, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Italy; (A.D.M.); (F.F.S.); (P.O.)
| | - Patrizia Oliva
- Department of Chemistry and Biology, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Italy; (A.D.M.); (F.F.S.); (P.O.)
| | - Francesco Lelj
- La.M.I. and LaSSCAM INSTM Sezione Basilicata, Dipartimento di Chimica, Università della Basilicata, Via dell’Ateneo Lucano 10, 85100 Potenza, Italy;
| | - Stefano Remiddi
- Department of Research and Development, MD-Italy, Via Cancelliera 12, Albano Laziale, 00041 Rome, Italy;
| | - Ludovica Silvani
- Department of Research and Development, MD-Italy, Via Cancelliera 12, Albano Laziale, 00041 Rome, Italy;
| | - Antonio Massa
- La.M.I. and LaSSCAM INSTM Sezione Basilicata, Dipartimento di Chimica, Università della Basilicata, Via dell’Ateneo Lucano 10, 85100 Potenza, Italy;
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11
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Aldrich KE, Livshits MY, Stromberg LR, Janicke MT, Nhu Lam M, Stein B, Wagner GL, Abergel RJ, Mukundan H, Kozimor SA, Lilley LM. Th IV-Desferrioxamine: characterization of a fluorescent bacterial probe. Dalton Trans 2021; 50:15310-15320. [PMID: 34636377 DOI: 10.1039/d1dt02177j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Diversifying our ability to guard against emerging pathogenic threats is essential for keeping pace with global health challenges, including those presented by drug-resistant bacteria. Some modern diagnostic and therapeutic innovations to address this challenge focus on targeting methods that exploit bacterial nutrient sequestration pathways, such as the desferrioxamine (DFO) siderophore used by Staphylococcus aureus (S. aureus) to sequester FeIII. Building on recent studies that have shown DFO to be a versatile vehicle for chemical delivery, we show proof-of-principle that the FeIII sequestration pathway can be used to deliver a potential radiotherapeutic. Our approach replaces the FeIII nutrient sequestered by H4DFO+ with ThIV and made use of a common fluorophore, FITC, which we covalently bonded to DFO to provide a combinatorial probe for simultaneous chelation paired with imaging and spectroscopy, H3DFO_FITC. Combining insight provided from FITC-based imaging with characterization by NMR spectroscopy, we demonstrated that the fluorescent DFO_FITC conjugate retained the ThIV chelation properties of native H4DFO+. Fluorescence microscopy with both [Th(DFO_FITC)] and [Fe(DFO_FITC)] complexes showed similar uptake by S. aureus and increased intercellular accumulation as compared to the FITC and unchelated H3DFO_FITC controls. Collectively, these results demonstrate the potential for the newly developed H3DFO_FITC conjugate to be used as a targeting vector and bacterial imaging probe for S. aureus. The results presented within provide a framework to expand H4DFO+ and H3DFO_FITC to relevant radiotherapeutics (like 227Th).
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Affiliation(s)
| | | | | | | | - Mila Nhu Lam
- Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA.
| | - Benjamin Stein
- Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA.
| | | | - Rebecca J Abergel
- Department of Chemistry, University of California, Berkeley, California, 94720, USA
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12
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Chen Z, Gai Y, Xie W, Guo H, Deng W, Li F, Jiang F. A rapid and effective synthetic route to functional cuboctahedron nanospheres. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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García-Romero Á, Martín-Álvarez JM, Colebatch AL, Plajer AJ, Miguel D, Álvarez CM, García-Rodríguez R. Synthesis of tris(3-pyridyl)aluminate ligand and its unexpected stability against hydrolysis: revealing cooperativity effects in heterobimetallic pyridyl aluminates. Dalton Trans 2021; 50:13059-13065. [PMID: 34581366 DOI: 10.1039/d1dt02351a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We report the elusive metallic anion [EtAl(3-py)3]- (3-py = 3-pyridyl) (1), the first member of the anionic tris(3-pyridyl) family. Unexpectedly, the lithium complex 1Li shows substantial protic stability against water and alcohols, unlike related tris(2-pyridyl)aluminate analogues. This stability appears to be related to the inability of the [EtAl(3-py)3]- anion to chelate Li+, which precludes a decomposition pathway involving Li/Al cooperativity.
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Affiliation(s)
- Álvaro García-Romero
- GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias, Universidad de Valladolid; Campus Miguel Delibes, 47011 Valladolid, Spain.
| | - Jose M Martín-Álvarez
- GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias, Universidad de Valladolid; Campus Miguel Delibes, 47011 Valladolid, Spain.
| | - Annie L Colebatch
- Chemistry Department. Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK.,Research School of Chemistry. Australian National University, Canberra, ACT, 2601, Australia
| | - Alex J Plajer
- Chemical Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Daniel Miguel
- GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias, Universidad de Valladolid; Campus Miguel Delibes, 47011 Valladolid, Spain.
| | - Celedonio M Álvarez
- GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias, Universidad de Valladolid; Campus Miguel Delibes, 47011 Valladolid, Spain.
| | - Raúl García-Rodríguez
- GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias, Universidad de Valladolid; Campus Miguel Delibes, 47011 Valladolid, Spain.
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14
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Direct quantification of cysteine and glutathione by 1H NMR based on β-cyclodextrin modified silver nanoparticles. Microchem J 2021. [DOI: 10.1016/j.microc.2021.106471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Kleks G, Holland DC, Porter J, Carroll AR. Natural products dereplication by diffusion ordered NMR spectroscopy (DOSY). Chem Sci 2021; 12:10930-10943. [PMID: 34476071 PMCID: PMC8372548 DOI: 10.1039/d1sc02940a] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/15/2021] [Indexed: 11/21/2022] Open
Abstract
Diffusion-ordered NMR spectroscopy (DOSY) can be used to analyze mixtures of compounds since resonances deriving from different compounds are distinguished by their diffusion coefficients (D). Previously, DOSY has mostly been used for organometallic and polymer analysis, we have now applied DOSY to investigate diffusion coefficients of structurally diverse organic compounds such as natural products (NP). The experimental Ds derived from 55 diverse NPs has allowed us to establish a power law relationship between D and molecular weight (MW) and therefore predict MW from experimental D. We have shown that D is also affected by factors such as hydrogen bonding, molar density and molecular shape of the compound and we have generated new models that incorporate experimentally derived variables for these factors so that more accurate predictions of MW can be calculated from experimental D. The recognition that multiple physicochemical properties affect D has allowed us to generate a polynomial equation based on multiple linear regression analysis of eight calculated physicochemical properties from 63 compounds to accurately correlate predicted D with experimental D for any known organic compound. This equation has been used to calculate predicted D for 217 043 compounds present in a publicly available natural product database (DEREP-NP) and to dereplicate known NPs in a mixture based on matching of experimental D and structural features derived from NMR analysis with predicted D and calculated structural features in the database. These models have been validated by the dereplication of a mixture of two known sesquiterpenes obtained from Tasmannia xerophila and the identification of new alkaloids from the bryozoan Amathia lamourouxi. These new methodologies allow the MW of compounds in mixtures to be predicted without the need for MS analysis, the dereplication of known compounds and identification of new compounds based solely on parameters derived by DOSY NMR. We report accurate DOSY NMR based molecular weight and diffusion coefficient prediction tools. These tools can be used to dereplicate known natural products from databases using structurally rich NMR data as a surrogate for mass spectrometric data.![]()
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Affiliation(s)
- Guy Kleks
- School of Environment and Science, Griffith University Gold Coast QLD 4222 Australia .,Griffith Institute for Drug Discovery, Griffith University Brisbane QLD 4111 Australia
| | - Darren C Holland
- School of Environment and Science, Griffith University Gold Coast QLD 4222 Australia .,Griffith Institute for Drug Discovery, Griffith University Brisbane QLD 4111 Australia
| | - Joshua Porter
- School of Environment and Science, Griffith University Gold Coast QLD 4222 Australia .,Griffith Institute for Drug Discovery, Griffith University Brisbane QLD 4111 Australia
| | - Anthony R Carroll
- School of Environment and Science, Griffith University Gold Coast QLD 4222 Australia .,Griffith Institute for Drug Discovery, Griffith University Brisbane QLD 4111 Australia
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16
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Zelga K, Pietrzak T, Han T, Justyniak I, Chwojnowska E, Sobota P, Lewiński J. Effectiveness of the Oxygenation over Classical Protonolysis Reactions: A Case of Alkylzinc Complexes Incorporating an Aminoalcoholate Ligand. Chemistry 2021; 27:14234-14239. [PMID: 34346529 DOI: 10.1002/chem.202102172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Indexed: 11/06/2022]
Abstract
Alkylzinc aminoalcoholates have emerged as powerful catalysts in organic synthesis and polymerization processes. Despite extensive research, difficulties in the rational design of these catalytic systems and in-depth understanding of their modes of action have hitherto been encountered. Most of the major obstacles stem largely from the relatively limited knowledge of the structure-activity relationship of zinc catalysts. In fact, the key active species are often generated in situ via the protonolysis of the alkylzinc precursors, which precludes their isolation and detailed characterization. Herein, the effectiveness of the oxygenation over the classical protonolysis in the synthesis of zinc alkylperoxides stabilized by an aminoalcoholate ligand is demonstrated. The controlled oxygenation of a tert-butylzinc complex incorporating a pridinolum (prinol) ligand leads to well-defined a dinuclear adduct of a (prinol)ZnOOtBu moiety with the parent tBuZn(prinol) complex and a novel dimer [tBuOOZn(prinol)]2 with terminal alkylperoxide groups. The observed reaction outcomes strongly depend on the reaction conditions. Although sparse examples of heteroleptic adducts of the [RZn(L)]x [ROOZn(L)]y -type are known, the herein reported homoleptic [ROOZn(L)]x aggregate is unprecedented. Strikingly, comparative studies involving reactions between tBuZn(prinol) and tert-butylhydroperoxide or ethanol revealed that the respective seemingly simple zinc alkylperoxides, or zinc alkoxides, respectively, are not accessible via the classical alcoholysis. We believe that these game-changing results concerning multifaceted chemistry of organozinc aminoalcoholates should pave the way for more rational development of various Zn-based catalytic systems.
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Affiliation(s)
- Karolina Zelga
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw, Poland
| | - Tomasz Pietrzak
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw, Poland
| | - Tomasz Han
- Faculty of Chemistry, University of Wrocław Polish Academy of Science, F. Joliot-Curie '4, 50-383, Wrocław, Poland
| | - Iwona Justyniak
- Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Elżbieta Chwojnowska
- Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Piotr Sobota
- Faculty of Chemistry, University of Wrocław Polish Academy of Science, F. Joliot-Curie '4, 50-383, Wrocław, Poland
| | - Janusz Lewiński
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664, Warsaw, Poland.,Institute of Physical Chemistry, Polish Academy of Science, Kasprzaka 44/52, 01-224, Warsaw, Poland
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17
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Gauld RM, McLellan R, Kennedy AR, Carson FJ, Barker J, Reid J, O'Hara CT, Mulvey RE. Structural Studies of Donor‐Free and Donor‐Solvated Sodium Carboxylates. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Richard M. Gauld
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
- Current address: Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstrasse 150 44801 Bochum Germany
| | - Ross McLellan
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Alan R. Kennedy
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Freya J. Carson
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Jim Barker
- Innospec Ltd, Innospec Manufacturing Park Oil Sites Road CH65 4EY Ellesmere Port Cheshire UK
| | - Jacqueline Reid
- Innospec Ltd, Innospec Manufacturing Park Oil Sites Road CH65 4EY Ellesmere Port Cheshire UK
| | - Charles T. O'Hara
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Robert E. Mulvey
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
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18
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Ramler J, Wüst L, Rempel A, Wolz L, Lichtenberg C. Bismuth Atoms in Hydrocarbon Ligands: Bismepines as Rigid, Ditopic Arene Donors in Coordination Chemistry. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jacqueline Ramler
- Julius-Maximilians-University Würzburg, Institute of Inorganic Chemistry, Am Hubland 97074, Würzburg, Germany
| | - Leonie Wüst
- Julius-Maximilians-University Würzburg, Institute of Inorganic Chemistry, Am Hubland 97074, Würzburg, Germany
| | - Anna Rempel
- Julius-Maximilians-University Würzburg, Institute of Inorganic Chemistry, Am Hubland 97074, Würzburg, Germany
| | - Laura Wolz
- Julius-Maximilians-University Würzburg, Institute of Inorganic Chemistry, Am Hubland 97074, Würzburg, Germany
| | - Crispin Lichtenberg
- Julius-Maximilians-University Würzburg, Institute of Inorganic Chemistry, Am Hubland 97074, Würzburg, Germany
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19
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Consistency of a dialyzable leucocyte extract manufactured at GMP facilities by nuclear magnetic resonance spectroscopy. J Pharm Biomed Anal 2021; 196:113940. [PMID: 33549874 DOI: 10.1016/j.jpba.2021.113940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 01/24/2021] [Accepted: 01/25/2021] [Indexed: 12/20/2022]
Abstract
The present work describes the development and validation of a first report including several non-invasive NMR schemes to identify parameters as local chemical environments, homo- and heteronuclear site-specific spin correlations, diffusion coefficient-dependent polydispersity indexes and quantification of identified peptide entities that composes a commercial human Dialyzable Leucocyte Extract (DLE), Transferon, an oral liquid formulation of low-molecular-weight peptides. The above parameters were useful indicators to verify reproducibility, consistency and homogeneity among the DLE batches manufactured at Good Manufacturing Practice (GMP) facilities and for batch-releasing purposes in a quality control laboratory. The results showed that peptide identity of the DLE is represented with both high reproducible one-dimensional proton spectra and diffusion coefficient distributions that predicts in turn a weight-average molecular weight of around 6.7-7.4 kDa and a mean polydispersity index of 1.13. The obtained NMR peptide fingerprint of the analyzed DLE allowed to i) confirm its structural homogeneity by line-shape analysis, ii) identify and quantify its peptide content within the total solution with qNMR methods iii) to confirm the robustness of the technique as a feasible alternative for routine analysis of Natural or non-Natural Complex Drugs, such as DLEs.
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20
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Dilchert K, Schmidt M, Großjohann A, Feichtner K, Mulvey RE, Gessner VH. Lösungsmitteleinflüsse auf die Struktur und Stabilität von Alkalimetallcarbenoiden. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011278] [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)
- Katharina Dilchert
- Lehrstuhl für Anorganische Chemie II Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde Glasgow G1 1XL UK
| | - Michelle Schmidt
- Lehrstuhl für Anorganische Chemie II Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Angela Großjohann
- Lehrstuhl für Anorganische Chemie II Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Kai‐Stephan Feichtner
- Lehrstuhl für Anorganische Chemie II Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
| | - Robert E. Mulvey
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde Glasgow G1 1XL UK
| | - Viktoria H. Gessner
- Lehrstuhl für Anorganische Chemie II Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstraße 150 44801 Bochum Deutschland
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21
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Dilchert K, Schmidt M, Großjohann A, Feichtner KS, Mulvey RE, Gessner VH. Solvation Effects on the Structure and Stability of Alkali Metal Carbenoids. Angew Chem Int Ed Engl 2021; 60:493-498. [PMID: 33006796 PMCID: PMC7821203 DOI: 10.1002/anie.202011278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Indexed: 12/26/2022]
Abstract
s‐Block metal carbenoids are carbene synthons and applied in a myriad of organic transformations. They exhibit a strong structure–activity relationship, but this is only poorly understood due to the challenging high reactivity and sensitivity of these reagents. Here, we report on systematic VT and DOSY NMR studies, XRD analyses as well as DFT calculations on a sulfoximinoyl‐substituted model system to explain the pronounced solvent dependency of the carbenoid stability. While the sodium and potassium chloride carbenoids showed high stabilities independent of the solvent, the lithium carbenoid was stable at room temperature in THF but decomposed at −10 °C in toluene. These divergent stabilities could be explained by the different structures formed in solution. In contrast to simple organolithium reagents, the monomeric THF‐solvate was found to be more stable than the dimer in toluene, since the latter more readily forms direct Li/Cl interactions which facilitate decomposition via α‐elimination.
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Affiliation(s)
- Katharina Dilchert
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.,WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Michelle Schmidt
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Angela Großjohann
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Kai-Stephan Feichtner
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Robert E Mulvey
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Viktoria H Gessner
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
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22
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Casey KC, Brown AM, Robinson JR. Yttrium and lanthanum bis(phosphine-oxide)methanides: structurally diverse, dynamic, and reactive. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01438a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Homoleptic yttrium and lanthanum complexes of bis(phosphineoxide) methanides, RE(HPhL)3 and RE2(HMeL)6, promote the first rare-earth mediated Horner-Wittig and acid-base chemistry consistent with multifunctional reactivity (Lewis-acid/Brønstedbase).
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23
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Zhao Q, Liu Y, Ma H, Qiao Y, Chao J, Hou X, Wang Y, Wang Y. Combination of pure shift NMR and chemical shift selective filters for analysis of Fischer-Tropsch waste-water. Anal Chim Acta 2020; 1110:131-140. [PMID: 32278388 DOI: 10.1016/j.aca.2020.03.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 03/05/2020] [Accepted: 03/07/2020] [Indexed: 01/14/2023]
Abstract
Fischer-Tropsch (F-T) process is an important synthesis route to acquire clean liquid fuels through modern coal chemical industry, which converts syngas (CO and H2) into hydrocarbon, and also generates oxygenates discharged as the F-T waste-water. These oxygen-containing compounds in F-T waste-water have the similar molecular weight and some are even isomers of each other. Hence, it is necessary to develop rapid and efficient analysis tools to obtain identification and quantitative information of the F-T waste-water. The pure shift NMR techniques provided only chemical shift information in one-dimension 1H NMR spectra, without homonuclear JH-H coupling. In this work, we tested and compared three pure shift NMR techniques (including Zangger-Sterk, PSYCHE and TSE-PSYCHE methods) in the analysis of two F-T waste-water model mixtures, genuine waste-water and two alcohol isomer mixtures. The results show that JH-H coupling multiplicities are collapsed into singlets corresponding to individual chemically distinct protons of the compound. For some severely overlapped signals in the pure shift NMR spectra, the chemical shift selective filters with TOCSY (CSSF-TOCSY) experiments were conducted to assist the signal assignment. Thus, pure shift NMR approaches can identify most signals of components, and CSSF-TOCSY can extract the signal of a specific compound. The combination of these two NMR techniques offers a powerful tool to analyze the F-T waste-water or other complex mixtures including isomer mixtures.
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Affiliation(s)
- Qi Zhao
- Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Yu Liu
- Department of Chemistry, Northern Michigan University, Marquette, MI, 49855, United States
| | - Hui Ma
- Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Yan Qiao
- Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Jianbin Chao
- Research Institute of Applied Chemistry, Shanxi University, Taiyuan, 030006, PR China
| | - Xianglin Hou
- Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Yuqi Wang
- Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Yingxiong Wang
- Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, PR China.
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24
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Evans R. The interpretation of small molecule diffusion coefficients: Quantitative use of diffusion-ordered NMR spectroscopy. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2020; 117:33-69. [PMID: 32471534 DOI: 10.1016/j.pnmrs.2019.11.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 11/20/2019] [Accepted: 11/20/2019] [Indexed: 06/11/2023]
Abstract
Measuring accurate molecular self-diffusion coefficients, D, by nuclear magnetic resonance (NMR) techniques has become routine as hardware, software and experimental methodologies have all improved. However, the quantitative interpretation of such data remains difficult, particularly for small molecules. This review article first provides a description of, and explanation for, the failure of the Stokes-Einstein equation to accurately predict small molecule diffusion coefficients, before moving on to three broadly complementary methods for their quantitative interpretation. Two are based on power laws, but differ in the nature of the reference molecules used. The third addresses the uncertainties in the Stokes-Einstein equation directly. For all three methods, a wide range of examples are used to show the range of chemistry to which diffusion NMR can be applied, and how best to implement the different methods to obtain quantitative information from the chemical systems studied.
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Affiliation(s)
- Robert Evans
- Aston Institute of Materials Research, School of Engineering and Applied Science, Aston University, Birmingham B4 7ET, United Kingdom.
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25
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Conejos-Sánchez I, Gallon E, Niño-Pariente A, Smith JA, De la Fuente AG, Di Canio L, Pluchino S, Franklin RJM, Vicent MJ. Polyornithine-based polyplexes to boost effective gene silencing in CNS disorders. NANOSCALE 2020; 12:6285-6299. [PMID: 31840717 DOI: 10.1039/c9nr06187h] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Gene silencing therapies have successfully suppressed the translation of target proteins, a strategy that holds great promise for the treatment of central nervous system (CNS) disorders. Advances in the current knowledge on multimolecular delivery vehicles are concentrated on overcoming the difficulties in delivery of small interfering (si)RNA to target tissues, which include anatomical accessibility, slow diffusion, safety concerns, and the requirement for specific cell uptake within the unique environment of the CNS. The present work addressed these challenges through the implementation of polyornithine derivatives in the construction of polyplexes used as non-viral siRNA delivery vectors. Physicochemical and biological characterization revealed biodegradability and biocompatibility of our polyornithine-based system and the ability to silence gene expression in primary oligodendrocyte progenitor cells (OPCs) effectively. In summary, the well-defined properties and neurological compatibility of this polypeptide-based platform highlight its potential utility in the treatment of CNS disorders.
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Affiliation(s)
- I Conejos-Sánchez
- Centro de Investigación Príncipe Felipe. Polymer Therapeutics Laboratory, C/Eduardo Primo Yúfera, 3, 46012 Valencia, Spain.
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26
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Zaccaria F, Zuccaccia C, Cipullo R, Macchioni A. Extraction of Reliable Molecular Information from Diffusion NMR Spectroscopy: Hydrodynamic Volume or Molecular Mass? Chemistry 2019; 25:9930-9937. [PMID: 30998838 DOI: 10.1002/chem.201900812] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Indexed: 01/31/2023]
Abstract
Measuring accurate translational self-diffusion coefficients (Dt ) by NMR techniques with modern spectrometers has become rather routine. In contrast, the derivation of reliable molecular information therefrom still remains a nontrivial task. In this paper, two established approaches to estimating molecular size in terms of hydrodynamic volume (VH ) or molecular weight (M) are compared. Ad hoc designed experiments allowed the critical aspects of their application to be explored by translating relatively complex theoretical principles into practical take-home messages. For instance, comparing the Dt values of three isosteric Cp2 MCl2 complexes (Cp=cyclopentadienyl, M=Ti, Zr, Hf), having significantly different molecular mass, provided an empirical demonstration that VH is the critical molecular property affecting Dt . This central concept served to clarify the assumptions behind the derivation of Dt =ƒ(M) power laws from the Stokes-Einstein equation. Some pitfalls in establishing log (Dt ) versus log (M) linear correlations for a set of species have been highlighted by further investigations of selected examples. The effectiveness of the Stokes-Einstein equation itself in describing the aggregation or polymerization of differently shaped species has been explored by comparing, for example, a ball-shaped silsesquioxane cage with its cigar-like dimeric form, or styrene with polystyrene macromolecules.
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Affiliation(s)
- Francesco Zaccaria
- Dipartimento di Chimica, Biologia e Biotecnologie and CIRCC, Università di Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy
| | - Cristiano Zuccaccia
- Dipartimento di Chimica, Biologia e Biotecnologie and CIRCC, Università di Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy
| | - Roberta Cipullo
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Via Cintia, 80126, Napoli, Italy
| | - Alceo Macchioni
- Dipartimento di Chimica, Biologia e Biotecnologie and CIRCC, Università di Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy
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27
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NMR analysis of the Fischer-Tropsch wastewater: Combination of 1D selective gradient TOCSY, 2D DOSY and qNMR. Anal Chim Acta 2019; 1066:21-27. [PMID: 31027531 DOI: 10.1016/j.aca.2019.04.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 04/03/2019] [Accepted: 04/06/2019] [Indexed: 01/14/2023]
Abstract
The Fischer-Tropsch (FT) process is a practical approach to convert synthesis gas (CO and H2) into hydrocarbons and oxygenates, and these product mixtures are usually well-characterized. However, the analysis of Fischer-Tropsch waste water (FTW) is still somewhat underdeveloped and the exact composition of FTW remains unclear. Herein, various qualitative NMR techniques, especially diffusion-ordered spectroscopy (DOSY) and one dimension (1D) selective gradient total correlation spectroscopy (SelTOCSY) were strategically applied in the analysis of FTW. The NMR results show that the DOSY technique can pseudo-separate most of components in complex mixtures over the diffusion dimension. The SelTOCSY technique is used as a supporting method in the cases where the DOSY technique cannot clearly distinguish overlapped signals. Moreover, the quantitative 1H NMR (qNMR) was further used to quantify the components of the sample. These routine and advanced qualitative and quantitative NMR technique utilized here provide a fast, effective and feasible method for the identification of complex mixtures in FTW, which might be a powerful and fast alternative to gas chromatography or high performance liquid chromatography for FTW research.
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28
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Aletti AB, Miljkovic A, Toma L, Bruno R, Armentano D, Gunnlaugsson T, Bergamaschi G, Amendola V. Halide-Controlled Extending–Shrinking Motion of a Covalent Cage. J Org Chem 2019; 84:4221-4228. [DOI: 10.1021/acs.joc.9b00219] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Anna B. Aletti
- School of Chemistry, Trinity College Dublin, The University of Dublin, 152-160 Pearse Street, Dublin 2, Ireland
| | - Ana Miljkovic
- Department of Chemistry, University of Pavia, v.le Taramelli 12, Pavia 27100, Italy
| | - Lucio Toma
- Department of Chemistry, University of Pavia, v.le Taramelli 12, Pavia 27100, Italy
| | - Rosaria Bruno
- Department of Chemistry & Chemical Technologies, via Pietro Bucci, Arcavacata di Rende, Cosenza 87036, Italy
| | - Donatella Armentano
- Department of Chemistry & Chemical Technologies, via Pietro Bucci, Arcavacata di Rende, Cosenza 87036, Italy
| | - Thorfinnur Gunnlaugsson
- School of Chemistry, Trinity College Dublin, The University of Dublin, 152-160 Pearse Street, Dublin 2, Ireland
| | - Greta Bergamaschi
- Consiglio Nazionale Delle Ricerche, Istituto di Chimica del Riconoscimento Molecolare (ICRM), via M. Bianco 9, Milano 20131, Italy
| | - Valeria Amendola
- Department of Chemistry, University of Pavia, v.le Taramelli 12, Pavia 27100, Italy
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29
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Mono- and Hexanuclear Zinc Halide Complexes with Soft Thiopyridazine Based Scorpionate Ligands. INORGANICS 2019. [DOI: 10.3390/inorganics7020024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Scorpionate ligands with three soft sulfur donor sites have become very important in coordination chemistry. Despite its ability to form highly electrophilic species, electron-deficient thiopyridazines have rarely been used, whereas the chemistry of electron-rich thioheterocycles has been explored rather intensively. Here, the unusual chemical behavior of a thiopyridazine (6-tert-butylpyridazine-3-thione, HtBuPn) based scorpionate ligand towards zinc is reported. Thus, the reaction of zinc halides with tris(6-tert-butyl-3-thiopyridazinyl)borate Na[TntBu] leads to the formation of discrete torus-shaped hexameric zinc complexes [TntBuZnX]6 (X = Br, I) with uncommonly long zinc halide bonds. In contrast, reaction of the sterically more demanding ligand K[TnMe,tBu] leads to decomposition, forming Zn(HPnMe,tBu)2X2 (X = Br, I). The latter can be prepared independently by reaction of the respective zinc halides and two equiv of HPnMe,tBu. The bromide compound was used as precursor which further reacts with K[TnMe,tBu] forming the mononuclear complex [TnMe,tBu]ZnBr(HPnMe,tBu). The molecular structures of all compounds were elucidated by single-crystal X-ray diffraction analysis. Characterization in solution was performed by means of 1H, 13C and DOSY NMR spectroscopy which revealed the hexameric constitution of [TntBuZnBr]6 to be predominant. In contrast, [TnMe,tBu]ZnBr(HPnMe,tBu) was found to be dynamic in solution.
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30
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Arrabal-Campos FM, Aguilera-Sáez LM, Fernández I. Algebraic Reconstruction Technique for Diffusion NMR Experiments. Application to the Molecular Weight Prediction of Polymers. J Phys Chem A 2019; 123:943-950. [DOI: 10.1021/acs.jpca.8b08584] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Francisco M. Arrabal-Campos
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, Universidad de Almería, Ctra. Sacramento, s/n, Almería, E-04120, Spain
| | - Luis M. Aguilera-Sáez
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, Universidad de Almería, Ctra. Sacramento, s/n, Almería, E-04120, Spain
| | - Ignacio Fernández
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, Universidad de Almería, Ctra. Sacramento, s/n, Almería, E-04120, Spain
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31
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Palenzuela M, Muñoz MT, Vega JF, Gutiérrez-Rodríguez Á, Cuenca T, Mosquera MEG. Heterobimetallic aluminate derivatives with bulky phenoxide ligands: a catalyst for selective vinyl polymerization. Dalton Trans 2019; 48:6435-6444. [DOI: 10.1039/c9dt00761j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
New aluminates as active catalysts for vinyl polymerization are described, as well as a strategy to crosslinked polymers from GMA in a controlled fashion.
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Affiliation(s)
- Miguel Palenzuela
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigacion en Química “Andres M. del Río” (IQAR) Universidad de Alcalá
- Campus Universitario
- Madrid
- Spain
| | - Mª Teresa Muñoz
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigacion en Química “Andres M. del Río” (IQAR) Universidad de Alcalá
- Campus Universitario
- Madrid
- Spain
| | - Juan F. Vega
- BIOPHYM
- Department of Macromolecular Physics
- Instituto de Estructura de la Materia
- IEM-CSIC
- 28006 Madrid
| | - Ángel Gutiérrez-Rodríguez
- Unidad de Difracción de rayos X – Monocristal
- Servicios Científico-Técnicos
- Universidad de Oviedo
- Spain
| | - Tomás Cuenca
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigacion en Química “Andres M. del Río” (IQAR) Universidad de Alcalá
- Campus Universitario
- Madrid
- Spain
| | - Marta E. G. Mosquera
- Departamento de Química Orgánica y Química Inorgánica
- Instituto de Investigacion en Química “Andres M. del Río” (IQAR) Universidad de Alcalá
- Campus Universitario
- Madrid
- Spain
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32
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Pasechnik MP, Matveeva AG, Lyssenko KA, Aysin RR, Smol'yakov AF, Zubavichus YV, Godovikov IA, Goryunov EI. Competing intramolecular vs. intermolecular hydrogen bonding in phosphoryl-containing secondary alkanols: A structural, spectroscopic and DFT study. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2018.08.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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33
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Yousefi R, Struble TJ, Payne JL, Vishe M, Schley ND, Johnston JN. Catalytic, Enantioselective Synthesis of Cyclic Carbamates from Dialkyl Amines by CO 2-Capture: Discovery, Development, and Mechanism. J Am Chem Soc 2018; 141:618-625. [PMID: 30582326 DOI: 10.1021/jacs.8b11793] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cyclic carbamates are a common feature of small-molecule therapeutics, offering a constrained hydrogen bond acceptor that is both polar and sterically small. Methods for their preparation most often focus first on amino alcohol synthesis and then reaction with phosgene or its equivalent. This report describes an enantioselective synthesis of cyclic carbamates in which carbon dioxide engages an unsaturated basic amine, facilitated by a bifunctional organocatalyst designed to stabilize a carbamic acid intermediate while activating it toward subsequent enantioselective carbon-oxygen bond formation. Six-membered cyclic carbamates are prepared in good yield with high levels of enantioselection, as constrained 1,3-amino alcohols featuring a chiral tertiary alcohol carbon. Spectroscopic analysis (NMR, DOSY) of various substrate-reagent combinations provides insight into the dominant species under the reaction conditions. Two peculiar requirements were identified to achieve highest consistency: a "Goldilocks" amount of water and the use of a noncrystalline form of the ligand. These atypical features of the final protocol notwithstanding, a diverse range of products could be prepared. Their functionalizations illustrate the versatility of the carbamates as precursors to enantioenriched small molecules.
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Affiliation(s)
- Roozbeh Yousefi
- Department of Chemistry and Vanderbilt Institute of Chemical Biology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Thomas J Struble
- Department of Chemistry and Vanderbilt Institute of Chemical Biology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Jenna L Payne
- Department of Chemistry and Vanderbilt Institute of Chemical Biology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Mahesh Vishe
- Department of Chemistry and Vanderbilt Institute of Chemical Biology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Nathan D Schley
- Department of Chemistry and Vanderbilt Institute of Chemical Biology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Jeffrey N Johnston
- Department of Chemistry and Vanderbilt Institute of Chemical Biology , Vanderbilt University , Nashville , Tennessee 37235 , United States
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34
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Hamdoun G, Bour C, Gandon V, Dumez JN. Empirical Estimation of the Molecular Weight of Gold Complexes in Solution by Pulsed-Field Gradient NMR. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00709] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ghanem Hamdoun
- Institut de Chimie des Substances Naturelles, CNRS UPR2301, Université Paris Sud, Université Paris-Saclay, 91190 Gif-Sur-Yvette, France
| | - Christophe Bour
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, CNRS UMR 8182, Université Paris Sud, Université Paris-Saclay, 91405 Orsay France
| | - Vincent Gandon
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, CNRS UMR 8182, Université Paris Sud, Université Paris-Saclay, 91405 Orsay France
- Laboratoire de Chimie Moléculaire, CNRS UMR 9168, Ecole Polytechnique, Université Paris-Saclay, Route de Saclay, 91128 Palaiseau cedex, France
| | - Jean-Nicolas Dumez
- Institut de Chimie des Substances Naturelles, CNRS UPR2301, Université Paris Sud, Université Paris-Saclay, 91190 Gif-Sur-Yvette, France
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35
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Bookser BC, Weinhouse MI, Burns AC, Valiere AN, Valdez LJ, Stanczak P, Na J, Rheingold AL, Moore CE, Dyck B. Solvent-Controlled, Site-Selective N-Alkylation Reactions of Azolo-Fused Ring Heterocycles at N1-, N2-, and N3-Positions, Including Pyrazolo[3,4-d]pyrimidines, Purines, [1,2,3]Triazolo[4,5]pyridines, and Related Deaza-Compounds. J Org Chem 2018; 83:6334-6353. [DOI: 10.1021/acs.joc.8b00540] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
| | | | | | | | | | | | | | - Arnold L. Rheingold
- Department of Chemistry, Crystallography Laboratory, University of California, San Diego, Urey Hall 5128, mail code 0358, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
| | - Curtis E. Moore
- Department of Chemistry, Crystallography Laboratory, University of California, San Diego, Urey Hall 5128, mail code 0358, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
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36
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Guang J, Duwald R, Maddaluno J, Oulyadi H, Lakhdar S, Gaumont AC, Harrison-Marchand A. Synthesis and Identification of Aryl and Alkyl Gem-Dilithium Phosphido-Boranes: A Boost to the Chemistry of Phosphandiides. Chemistry 2018. [PMID: 29533492 DOI: 10.1002/chem.201800742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jie Guang
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Romain Duwald
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Jacques Maddaluno
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Hassan Oulyadi
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Sami Lakhdar
- Normandie Université, ENSICAEN, UNICAEN, CNRS; Laboratoire LCMT (UMR 6507 & FR 3038); 14000 Caen France
| | - Annie-Claude Gaumont
- Normandie Université, ENSICAEN, UNICAEN, CNRS; Laboratoire LCMT (UMR 6507 & FR 3038); 14000 Caen France
| | - Anne Harrison-Marchand
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
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37
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Evans R, Dal Poggetto G, Nilsson M, Morris GA. Improving the Interpretation of Small Molecule Diffusion Coefficients. Anal Chem 2018; 90:3987-3994. [PMID: 29481057 DOI: 10.1021/acs.analchem.7b05032] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diffusion-ordered NMR spectroscopy (DOSY) is increasingly widely used for the analysis of mixtures by NMR spectroscopy, dispersing the signals of different species according to their diffusion coefficients. DOSY is used primarily to distinguish between the signals of different species, with the interpretation of the diffusion coefficients observed usually being purely qualitative, for example to deduce whether one species is bigger or smaller than another. In principle, the actual values of diffusion coefficient obtained carry important information about the sizes of different species and on interactions between species, but the relationship between diffusion coefficient and molecular mass is in general a very complex one. Here a recently proposed analytical relationship between diffusion coefficient and molecular mass for the restricted case of small organic molecules is tested against a wide range of data from the scientific literature and generalized to cover a range of solvents and temperatures.
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Affiliation(s)
- Robert Evans
- Aston Institute of Materials Research, School of Engineering and Applied Science , Aston University , Birmingham , B4 7ET , U.K
| | | | - Mathias Nilsson
- School of Chemistry , University of Manchester , Manchester M13 9PL , U.K
| | - Gareth A Morris
- School of Chemistry , University of Manchester , Manchester M13 9PL , U.K
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38
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Rieb J, Dominelli B, Mayer D, Jandl C, Drechsel J, Heydenreuter W, Sieber SA, Kühn FE. Influence of wing-tip substituents and reaction conditions on the structure, properties and cytotoxicity of Ag(i)- and Au(i)-bis(NHC) complexes. Dalton Trans 2018; 46:2722-2735. [PMID: 28174778 DOI: 10.1039/c6dt04559f] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The formation of different conformers of dinuclear silver(i) and gold(i) 1,1'-(2-hydroxyethane-1,1-diyl) bridge-functionalized bis(NHC) complexes with various wing-tip substituents (R = methyl, isopropyl and mesityl) has been investigated using multinuclear NMR spectroscopy and SC-XRD as well as DFT calculations. The ratio of anti/syn isomers strongly depends both on wing-tip substituents and the metal. Moreover, the reaction temperature plays a significant role during the transmetallation process for the ratio of gold(i) conformers, which is further affected by purification procedures. All obtained Au(i)-bis(NHC) complexes have been applied in a standard MTT assay performed for screening the antiproliferative activity against human lung and liver cancer cells. Strong evidence for a significant influence of both wing-tip substituents and conformation on the cytotoxic properties of the applied complexes has been found.
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Affiliation(s)
- Julia Rieb
- Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany.
| | - Bruno Dominelli
- Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany.
| | - David Mayer
- Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany.
| | - Christian Jandl
- Catalysis Research Center, Technische Universität München, Ernst-Otto-Fischer Straße 1, D-85747 Garching bei München, Germany
| | - Jonas Drechsel
- Chair of Organic Chemistry II, Department of Chemistry, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching bei München, Germany
| | - Wolfgang Heydenreuter
- Chair of Organic Chemistry II, Department of Chemistry, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching bei München, Germany
| | - Stephan A Sieber
- Chair of Organic Chemistry II, Department of Chemistry, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching bei München, Germany
| | - Fritz E Kühn
- Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany.
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39
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Muñoz MT, Palenzuela M, Cuenca T, Mosquera MEG. Aluminum Aryloxide Compounds as Very Active Catalysts for Glycidyl Methacrylate Selective Ring-Opening Polymerization. ChemCatChem 2018. [DOI: 10.1002/cctc.201701377] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- M. Teresa Muñoz
- Departamento de Química Orgánica y Química Inorgánica; Instituto de Investigación Química “Andrés M. del Río”; Universidad de Alcalá; Campus Universitario E-28871 Alcalá de Henares Spain
| | - Miguel Palenzuela
- Departamento de Química Orgánica y Química Inorgánica; Instituto de Investigación Química “Andrés M. del Río”; Universidad de Alcalá; Campus Universitario E-28871 Alcalá de Henares Spain
| | - Tomás Cuenca
- Departamento de Química Orgánica y Química Inorgánica; Instituto de Investigación Química “Andrés M. del Río”; Universidad de Alcalá; Campus Universitario E-28871 Alcalá de Henares Spain
| | - Marta E. G. Mosquera
- Departamento de Química Orgánica y Química Inorgánica; Instituto de Investigación Química “Andrés M. del Río”; Universidad de Alcalá; Campus Universitario E-28871 Alcalá de Henares Spain
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40
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García-Iglesias M, Huerta E. Towards new multivalent supramolecular helical structures based on phthalocyanines for PDT applications. J PORPHYR PHTHALOCYA 2018. [DOI: 10.1142/s1088424617500766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The self-assembly of [Formula: see text]-D-glucose octafunctionalized Zn(II) phtalocyanine (ZnPc) in aqueous media has been investigated using different techniques such as UV, CD and diffusion-ordered [Formula: see text]H-NMR spectroscopy (DOSY). The formation of supramolecular columnar helical aggregates with a preferred handedness due to the presence of the sugar moiety has been confirmed by these techniques. Moreover, the stability of the supramolecular polymers formed has been assessed by using pyridine as a zinc ligand, disrupting the aggregates or inducing their formation by dilution of the system.
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Affiliation(s)
- Miguel García-Iglesias
- Institute of Complex Molecular Systems, Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
- Department of Organic Chemistry, Universidad Autónoma de Madrid (UAM), Calle Francisco Tomás y Valiente, 7, 28049 Madrid, Spain
| | - Elisa Huerta
- Institute of Complex Molecular Systems, Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
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41
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Abubekerov M, Wei J, Swartz KR, Xie Z, Pei Q, Diaconescu PL. Preparation of multiblock copolymers via step-wise addition of l-lactide and trimethylene carbonate. Chem Sci 2018; 9:2168-2178. [PMID: 29719690 PMCID: PMC5903370 DOI: 10.1039/c7sc04507g] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/10/2018] [Indexed: 01/14/2023] Open
Abstract
The synthesis of up to pentablock copolymers from various combinations of l-lactide and trimethylene carbonate was accomplished using a dinuclear zinc complex, and the physical, thermal, and mechanical properties of the resulting copolymers evaluated.
Poly(l-lactide) (PLA) is a bioderived and biodegradable polymer that has limited applications due to its hard and brittle nature. Incorporation of 1,3-trimethylene carbonate into PLA, in a block copolymer fashion, improves the mechanical properties, while retaining the biodegradability of the polymer, and broadens its range of applications. However, the preparation of 1,3-trimethylene carbonate (TMC)/l-lactide (LA) copolymers beyond diblock and triblock structures has not been reported, with explanations focusing mostly on thermodynamic reasons that impede the copolymerization of TMC after lactide. We discuss the preparation of multiblock copolymers via the ring opening polymerization (ROP) of LA and TMC, in a step-wise addition, by a ferrocene-chelating heteroscorpionate zinc complex, {[fc(PPh2)(BH[(3,5-Me)2pz]2)]Zn(μ-OCH2Ph)}2 ([(fcP,B)Zn(μ-OCH2Ph)]2, fc = 1,1′-ferrocenediyl, pz = pyrazole). The synthesis of up to pentablock copolymers, from various combinations of LA and TMC, was accomplished and the physical, thermal, and mechanical properties of the resulting copolymers evaluated.
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Affiliation(s)
- Mark Abubekerov
- Department of Chemistry and Biochemistry , University of California , Los Angeles , CA 90095 , USA .
| | - Junnian Wei
- Department of Chemistry and Biochemistry , University of California , Los Angeles , CA 90095 , USA .
| | - Kevin R Swartz
- Department of Chemistry and Biochemistry , University of California , Los Angeles , CA 90095 , USA .
| | - Zhixin Xie
- Department of Materials Science and Engineering , University of California , Los Angeles , CA 90095 , USA
| | - Qibing Pei
- Department of Materials Science and Engineering , University of California , Los Angeles , CA 90095 , USA
| | - Paula L Diaconescu
- Department of Chemistry and Biochemistry , University of California , Los Angeles , CA 90095 , USA .
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42
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Nahra F, Van Hecke K, Kennedy AR, Nelson DJ. Coinage metal complexes of selenoureas derived from N-heterocyclic carbenes. Dalton Trans 2018; 47:10671-10684. [DOI: 10.1039/c8dt01506f] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The coordination chemistry of selenoureas derived from N-heterocyclic carbenes with copper and silver is explored, and compared to previous work with gold.
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Affiliation(s)
- Fady Nahra
- Department of Chemistry and Centre for Sustainable Chemistry
- Ghent University
- 9000 Ghent
- Belgium
| | - Kristof Van Hecke
- Department of Chemistry and Centre for Sustainable Chemistry
- Ghent University
- 9000 Ghent
- Belgium
| | - Alan R. Kennedy
- WestCHEM Department of Pure & Applied Chemistry
- University of Strathclyde
- Glasgow
- UK
| | - David J. Nelson
- WestCHEM Department of Pure & Applied Chemistry
- University of Strathclyde
- Glasgow
- UK
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43
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Hamdoun G, Guduff L, van Heijenoort C, Bour C, Gandon V, Dumez JN. Spatially encoded diffusion-ordered NMR spectroscopy of reaction mixtures in organic solvents. Analyst 2018; 143:3458-3464. [DOI: 10.1039/c8an00434j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Using a spatial encoding of the diffusion dimension, DOSY NMR data are acquired in less than one second for reaction mixtures in organic solvents.
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Affiliation(s)
- Ghanem Hamdoun
- Institut de Chimie des Substances Naturelles
- CNRS UPR2301
- Univ. Paris Sud
- Université Paris-Saclay
- 91190 Gif-Sur-Yvette
| | - Ludmilla Guduff
- Institut de Chimie des Substances Naturelles
- CNRS UPR2301
- Univ. Paris Sud
- Université Paris-Saclay
- 91190 Gif-Sur-Yvette
| | - Carine van Heijenoort
- Institut de Chimie des Substances Naturelles
- CNRS UPR2301
- Univ. Paris Sud
- Université Paris-Saclay
- 91190 Gif-Sur-Yvette
| | - Christophe Bour
- Institut de Chimie Moléculaire et des Matériaux d'Orsay
- CNRS UMR 8182
- Univ. Paris Sud
- Université Paris-Saclay
- 91405 Orsay
| | - Vincent Gandon
- Institut de Chimie Moléculaire et des Matériaux d'Orsay
- CNRS UMR 8182
- Univ. Paris Sud
- Université Paris-Saclay
- 91405 Orsay
| | - Jean-Nicolas Dumez
- Institut de Chimie des Substances Naturelles
- CNRS UPR2301
- Univ. Paris Sud
- Université Paris-Saclay
- 91190 Gif-Sur-Yvette
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44
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Arrabal-Campos FM, Álvarez JD, García-Sancho A, Fernández I. Molecular weight prediction in polystyrene blends. Unprecedented use of a genetic algorithm in pulse field gradient spin echo (PGSE) NMR. SOFT MATTER 2017; 13:6620-6626. [PMID: 28920614 DOI: 10.1039/c7sm01569k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A genetic algorithm that uses boxcar functions (diffGA) has been applied for the first time in PGSE NMR. It reconstructs accurate diffusion coefficients for all the components of the mixture, and therefore predicts correct weight-average molecular weights for all of them. The results reported herein complement those obtained with established methods such as ITAMeD, CONTIN and TRAIn algorithms, and provide a detailed solution picture. Its robustness and limits have been stretched in order to ascertain the minimum separation within diffusion coefficients or relative proportion between components. In addition, the new genetic algorithm has been also applied to a mixture of small molecules, providing excellent results at very low computational times.
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Affiliation(s)
- Francisco M Arrabal-Campos
- Department of Chemistry and Physics, Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
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45
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Nifant'ev IE, Shlyakhtin AV, Bagrov VV, Minyaev ME, Churakov AV, Karchevsky SG, Birin KP, Ivchenko PV. Mono-BHT heteroleptic magnesium complexes: synthesis, molecular structure and catalytic behavior in the ring-opening polymerization of cyclic esters. Dalton Trans 2017; 46:12132-12146. [PMID: 28869269 DOI: 10.1039/c7dt02469j] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Numerous heteroleptic 2,6-di-tert-butyl-4-methylphenolate (BHT) magnesium complexes have been synthesized by treatment of (BHT)MgBu(THF)2 with various alcohols. Molecular structures of the complexes have been determined by X-ray diffraction. The magnesium coordination number in [(BHT)Mg(μ-OBn)(THF)]2 (3) and [(BHT)Mg(μ-O-tert-BuC6H4)(THF)]2 (4) is equal to 4. Complexes formed from esters of glycolic and lactic acids, [(BHT)Mg(μ-OCH2COOEt)(THF)]2 (5) and [(BHT)Mg(μ-OCH(CH3)COOCH2COOtBu)(THF)]2 (6) contain chelate fragments with pentacoordinated magnesium. Compounds 3-6 contain THF molecules coordinated to magnesium atoms. Complex {(BHT)Mg[μ-O(CH2)3CON(CH3)2]}2 (7) does not demonstrate any tendency to form an adduct with THF. It has been experimentally determined that complexes 3 and 5 are highly active catalysts of lactide polymerization. The activity of 4 is rather low, and complex 7 demonstrates moderate productivity. According to DOSY NMR experiments, compounds 3 and 5 retain their dimeric structures even in THF. The free energies of model dimeric [(DBP)Mg(μ-OMe)(Sub)]2 and monomeric (DBP)Mg(OMe)(Sub)2 products on treatment of [(DBP)Mg(μ-OMe)(THF)]2 with a series of σ-electron donors (Sub) have been estimated by DFT calculations. These results demonstrate that the substitution of THF by Sub in a dimeric molecule is an energetically allowed process, whereas the dissociation of dimers is energetically unfavorable. DFT modeling of ε-CL and (dl)-lactide ROP catalyzed by dimeric and monomeric complexes showed that a cooperative effect of two magnesium atoms occurs within the ROP for binuclear catalytic species. A comparison of the reaction profiles for ROP catalyzed by binuclear and mononuclear species allowed us to conclude that the binuclear mechanism is favorable in early stages of ROP initiated by dimers 3 and 5.
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Affiliation(s)
- I E Nifant'ev
- M.V. Lomonosov Moscow State University, Department of Chemistry, Moscow, Russian Federation. and A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow, Russian Federation
| | - A V Shlyakhtin
- M.V. Lomonosov Moscow State University, Department of Chemistry, Moscow, Russian Federation.
| | - V V Bagrov
- M.V. Lomonosov Moscow State University, Department of Chemistry, Moscow, Russian Federation.
| | - M E Minyaev
- A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow, Russian Federation
| | - A V Churakov
- N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, 31 Leninsky Prospect, 119991, Moscow, Russian Federation
| | - S G Karchevsky
- Institute of Petroleum Refining and Petrochemistry of the Republic of Bashkortostan, 12 Iniciativnaya Str., 450065, Ufa, Russian Federation
| | - K P Birin
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31 Leninsky Prospect, Building 4, 119071, Moscow, Russian Federation
| | - P V Ivchenko
- M.V. Lomonosov Moscow State University, Department of Chemistry, Moscow, Russian Federation. and A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow, Russian Federation
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46
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Kreyenschmidt AK, Bachmann S, Niklas T, Stalke D. Molecular Weight Estimation of Molecules Incorporating Heavier Elements from van-der-Waals Corrected ECC-DOSY. ChemistrySelect 2017. [DOI: 10.1002/slct.201701497] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Anne-Kathrin Kreyenschmidt
- Institut für Anorganische Chemie der; Georg-August-Universität Göttingen; Tammannstraße 4 37077 Göttingen
| | - Sebastian Bachmann
- Institut für Anorganische Chemie der; Georg-August-Universität Göttingen; Tammannstraße 4 37077 Göttingen
| | - Thomas Niklas
- Institut für Anorganische Chemie der; Georg-August-Universität Göttingen; Tammannstraße 4 37077 Göttingen
| | - Dietmar Stalke
- Institut für Anorganische Chemie der; Georg-August-Universität Göttingen; Tammannstraße 4 37077 Göttingen
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47
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Barozzino-Consiglio G, Hamdoun G, Fressigné C, Harrison-Marchand A, Maddaluno J, Oulyadi H. A Combined 1
H/6
Li NMR DOSY Strategy Finally Uncovers the Structure of Isopropyllithium in THF. Chemistry 2017; 23:12475-12479. [DOI: 10.1002/chem.201702990] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Indexed: 11/09/2022]
Affiliation(s)
| | - Ghanem Hamdoun
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Catherine Fressigné
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Anne Harrison-Marchand
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Jacques Maddaluno
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
| | - Hassan Oulyadi
- Normandie Université, UNIROUEN, INSA de Rouen, CNRS; Laboratoire COBRA (UMR 6014 & FR 3038); 76000 Rouen France
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48
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Gorsline BJ, Wang L, Ren P, Carrow BP. C–H Alkenylation of Heteroarenes: Mechanism, Rate, and Selectivity Changes Enabled by Thioether Ligands. J Am Chem Soc 2017. [DOI: 10.1021/jacs.7b03887] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bradley J. Gorsline
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Long Wang
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Peng Ren
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Brad P. Carrow
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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49
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Tai O, Hopson R, Williard PG. Ligand Binding Constants to Lithium Hexamethyldisilazide Determined by Diffusion-Ordered NMR Spectroscopy. J Org Chem 2017; 82:6223-6231. [PMID: 28562035 DOI: 10.1021/acs.joc.7b00800] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report the direct measurement of ligand-binding constants of organolithium complexes using a 1H NMR/diffusion-ordered NMR spectroscopy (DOSY) titration technique. Lithium hexamethyldisilazide complexes with ethereal and ester donor ligands (THF, diethyl ether, MTBE, THP, tert-butyl acetate) are characterized using 1H NMR and X-ray crystallography. Their aggregation and solvation states are confirmed using diffusion coefficient-formula weight correlation analysis, and the 1H NMR/DOSY titration technique is applied to obtain their binding constants. Our work suggests that steric hindrance of ethereal ligands plays an important role in the aggregation, solvation, and reactivity of these complexes. It is noteworthy that diffusion methodology is utilized to obtain binding constants.
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Affiliation(s)
- Onkei Tai
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Russell Hopson
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Paul G Williard
- Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
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50
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Xu C, Wan Y, Chen D, Gao C, Yin H, Fetherston D, Kupce E, Lopez G, Ameduri B, Twum EB, Wyzgoski FJ, Li X, McCord EF, Rinaldi PL. 19 F DOSY diffusion-NMR spectroscopy of fluoropolymers. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:472-484. [PMID: 27283595 DOI: 10.1002/mrc.4454] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 03/16/2016] [Accepted: 04/20/2016] [Indexed: 06/06/2023]
Abstract
A new pulse sequence for obtaining 19 F detected DOSY (diffusion ordered spectroscopy) spectra of fluorinated molecules is presented and used to study fluoropolymers based on vinylidene fluoride and chlorotrifluoroethylene. The performance of 19 F DOSY NMR experiments (and in general any type of NMR experiment) on fluoropolymers creates some unique complications that very often prevent detection of important signals. Factors that create these complications include: (1) the presence of many scalar couplings among 1 H, 19 F and 13 C; (2) the large magnitudes of many 19 F homonuclear couplings (especially 2 JFF ); (3) the large 19 F chemical shift range; and (4) the low solubility of these materials (which requires that experiments be performed at high temperatures). A systematic study of the various methods for collecting DOSY NMR data, and the adaptation of these methods to obtain 19 F detected DOSY data, has been performed using a mixture of low molecular weight, fluorinated model compounds. The best pulse sequences and optimal experimental conditions have been determined for obtaining 19 F DOSY spectra. The optimum pulse sequences for acquiring 19 F DOSY NMR data have been determined for various circumstances taking into account the spectral dispersion, number and magnitude of couplings present, and experimental temperature. Pulse sequences and experimental parameters for optimizing these experiments for the study of fluoropolymers have been studied. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Chenglong Xu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Yingbo Wan
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Dongxue Chen
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Chun Gao
- Department of Chemistry, University of Akron, 190 East Buchtel Commons, Akron, OH, 44325-3601, USA
| | - Hongnan Yin
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Daniel Fetherston
- Department of Chemistry, University of Akron, 190 East Buchtel Commons, Akron, OH, 44325-3601, USA
| | - Eriks Kupce
- Agilent, Bruker BioSpin, Coventry, CV4 9GH, UK
| | - Gerald Lopez
- Ingénierie and Architectures Macromoléculaires, Institut Charles Gerhardt, École Nationale Supérieure de Chimie de Montpellier, 8 Rue de l'École Normale, 34296, Montpellier, France
| | - Bruno Ameduri
- Ingénierie and Architectures Macromoléculaires, Institut Charles Gerhardt, École Nationale Supérieure de Chimie de Montpellier, 8 Rue de l'École Normale, 34296, Montpellier, France
| | - Eric B Twum
- Department of Chemistry, University of Akron, 190 East Buchtel Commons, Akron, OH, 44325-3601, USA
- Indiana University, Department of Chemistry, 800 E. Kirkwood Ave., Bloomington, IN, 47405-7102, USA
| | - Faith J Wyzgoski
- Department of Chemistry and Biochemistry, The Ohio State University, 1760 University Drive, Mansfield, OH, 44906, USA
| | - Xiaohong Li
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Elizabeth F McCord
- E. I. Du Pont de Nemours and Co, Experimental Station, Wilmington, DE, 19880-0402, USA
| | - Peter L Rinaldi
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
- Department of Chemistry, University of Akron, 190 East Buchtel Commons, Akron, OH, 44325-3601, USA
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