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Gallo-Rodriguez C, Rodriguez JB. Organoselenium Compounds in Medicinal Chemistry. ChemMedChem 2024:e202400063. [PMID: 38778500 DOI: 10.1002/cmdc.202400063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 05/09/2024] [Accepted: 05/22/2024] [Indexed: 05/25/2024]
Abstract
The chemical and biological interest in this element and the molecules bearing selenium has been exponentially growing over the years. Selenium, formerly designated as a toxin, becomes a vital trace element for life that appears as selenocysteine and its dimeric form, selenocystine, in the active sites of selenoproteins, which catalyze a wide variety of reactions, including the detoxification of reactive oxygen species and modulation of redox activities. From the point of view of drug developments, organoselenium drugs are isosteres of sulfur-containing and oxygen-containing drugs with the advantage that the presence of the selenium atom confers antioxidant properties and high lipophilicity, which would increase cell membrane permeation leading to better oral bioavailability. This statement is the paramount relevance considering the big number of clinically employed compounds bearing sulfur or oxygen atoms in their structures including nucleosides and carbohydrates. Thus, in this article we have focused on the relevant features of the application of selenium in medicinal chemistry. With the increasing interest in selenium chemistry, we have attempted to highlight the most significant published data on this subject, mainly concentrating the analysis on the last years. In consequence, the recent advances of relevant pharmacological organoselenium compounds are discussed.
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Affiliation(s)
- Carola Gallo-Rodriguez
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA, Buenos Aires, Argentina
- CONICET-Universidad de Buenos Aires, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), C1428EHA, Buenos Aires, Argentina
| | - Juan B Rodriguez
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA, Buenos Aires, Argentina
- CONICET-Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos en Química Orgánica (UMYMFOR), C1428EHA, Buenos, Aires, Argentina
- CONICET-Universidad de Buenos Aires, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), C1428EHA, Buenos Aires, Argentina
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2
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Müller VVL, Simpson PV, Peng K, Basu U, Moreth D, Nagel C, Türck S, Oehninger L, Ott I, Schatzschneider U. Taming the Biological Activity of Pd(II) and Pt(II) Complexes with Triazolato "Protective" Groups: 1H, 77Se Nuclear Magnetic Resonance and X-ray Crystallographic Model Studies with Selenocysteine to Elucidate Differential Thioredoxin Reductase Inhibition. Inorg Chem 2023; 62:16203-16214. [PMID: 37713601 DOI: 10.1021/acs.inorgchem.3c02701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/17/2023]
Abstract
The biological activity of Pd(II) and Pt(II) complexes toward three different cancer cell lines as well as inhibition of selenoenzyme thioredoxin reductase (TrxR) was modulated in an unexpected way by the introduction of triazolate as a "protective group" to the inner metal coordination sphere using the iClick reaction of [M(N3)(terpy)]PF6 [M = Pd(II) or Pt(II) and terpy = 2,2':6',2″-terpyridine] with an electron-poor alkyne. In a cell proliferation assay using A549, HT-29, and MDA-MB-231 human cancer cell lines, the palladium compound was significantly more potent than the isostructural platinum analogue and exhibited submicromolar activity on the most responsive cell line. This difference was also reflected in the inhibitory efficiency toward TrxR with IC50 values of 0.1 versus 5.4 μM for the Pd(II) and Pt(II) complexes, respectively. UV/Vis kinetic studies revealed that the Pt compound binds to selenocysteine faster than to cysteine [k = (22.9 ± 0.2)·10-3 vs (7.1 ± 0.2)·10-3 s-1]. Selective triazolato ligand exchange of the title compounds with cysteine (Hcys) and selenocysteine (Hsec)─but not histidine (His) and 9-ethylguanine (9EtG)─was confirmed by 1H, 77Se, and 195Pt NMR spectroscopy. Crystal structures of three of the four ligand exchange products were obtained, including [Pt(sec)(terpy)]PF6 as the first metal complex of selenocysteine to be structurally characterized.
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Affiliation(s)
- Victoria V L Müller
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Peter V Simpson
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Kun Peng
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Uttara Basu
- Institut für Medizinische und Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstr. 55, D-38106 Braunschweig, Germany
| | - Dominik Moreth
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Christoph Nagel
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Sebastian Türck
- Institut für Medizinische und Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstr. 55, D-38106 Braunschweig, Germany
| | - Luciano Oehninger
- Institut für Medizinische und Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstr. 55, D-38106 Braunschweig, Germany
| | - Ingo Ott
- Institut für Medizinische und Pharmazeutische Chemie, Technische Universität Braunschweig, Beethovenstr. 55, D-38106 Braunschweig, Germany
| | - Ulrich Schatzschneider
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
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3
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Quinn CM, Xu S, Hou G, Chen Q, Sail D, Byrd RA, Rozovsky S. 77Se- 13C based dipolar correlation experiments to map selenium sites in microcrystalline proteins. JOURNAL OF BIOMOLECULAR NMR 2022; 76:29-37. [PMID: 35320434 PMCID: PMC9195563 DOI: 10.1007/s10858-022-00390-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Sulfur-containing sites in proteins are of great importance for both protein structure and function, including enzymatic catalysis, signaling pathways, and recognition of ligands and protein partners. Selenium-77 is an NMR active spin-1/2 nucleus that shares many physiochemical properties with sulfur and can be readily introduced into proteins at sulfur sites without significant perturbations to the protein structure. The sulfur-containing amino acid methionine is commonly found at protein-protein or protein-ligand binding sites. Its selenium-containing counterpart, selenomethionine, has a broad chemical shift dispersion useful for NMR-based studies of complex systems. Methods such as (1H)-77Se-13C double cross polarization or {77Se}-13C REDOR could be valuable to map the local environment around selenium sites in proteins but have not been demonstrated to date. In this work, we explore these dipolar transfer mechanisms for structural characterization of the GB1 V39SeM variant of the model protein GB1 and demonstrate that 77Se-13C based correlations can be used to map the local environment around selenium sites in proteins. We have found that the general detection limit is ~ 5 Å, but longer range distances up to ~ 7 Å can be observed as well. This study establishes a framework for the future characterization of selenium sites at protein-protein or protein-ligand binding interfaces.
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Affiliation(s)
- Caitlin M. Quinn
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Shiping Xu
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Guangjin Hou
- State Key Laboratory of Catalysis, National Laboratory for Clean Energy, 2011-Collaborative Innovation Center of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, China
| | - Qingqing Chen
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Deepak Sail
- Chemistry and Synthesis Center, National Heart Lung and Blood Institute, Bethesda, MD, USA
| | - R. Andrew Byrd
- Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Sharon Rozovsky
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
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Mames A, Pietrzak M, Bernatowicz P, Kubas A, Luboradzki R, Ratajczyk T. NMR Crystallography Enhanced by Quantum Chemical Calculations and Liquid State NMR Spectroscopy for the Investigation of Se-NHC Adducts*. Chemistry 2021; 27:16477-16487. [PMID: 34606111 DOI: 10.1002/chem.202102800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Indexed: 11/11/2022]
Abstract
N-heterocyclic carbene ligands (NHC) are widely utilized in catalysis and material science. They are characterized by their steric and electronic properties. Steric properties are usually quantified on the basis of their static structure, which can be determined by X-ray diffraction. The electronic properties are estimated in the liquid state; for example, via the 77 Se liquid state NMR of Se-NHC adducts. We demonstrate that 77 Se NMR crystallography can contribute to the characterization of the structural and electronic properties of NHC in solid and liquid states. Selected Se-NHC adducts are investigated via 77 Se solid state NMR and X-ray crystallography, supported by quantum chemical calculations. This investigation reveals a correlation between the molecular structure of adducts and NMR parameters, including not only isotropic chemical shifts but also the other chemical shift tensor components. Afterwards, the liquid state 77 Se NMR data is presented and interpreted in terms of the quantum chemistry modelling. The discrepancy between the structural and electronic properties, and in particular the π-accepting abilities of adducts in the solid and liquid states is discussed. Finally, the 13 C isotropic chemical shift from the liquid state NMR and the 13 C tensor components are also discussed, and compared with their 77 Se counterparts. 77 Se NMR crystallography can deliver valuable information about NHC ligands, and together with liquid state 77 Se NMR can provide an in-depth outlook on the properties of NHC ligands.
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Affiliation(s)
- Adam Mames
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Mariusz Pietrzak
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Piotr Bernatowicz
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Adam Kubas
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Roman Luboradzki
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Tomasz Ratajczyk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
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5
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Zhou B, Guo X, Yang N, Huang Z, Huang L, Fang Z, Zhang C, Li L, Yu C. Surface engineering strategies of gold nanomaterials and their applications in biomedicine and detection. J Mater Chem B 2021; 9:5583-5598. [PMID: 34161402 DOI: 10.1039/d1tb00181g] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gold nanomaterials have potential applications in biosensors and biomedicine due to their controllable synthesis steps, high biocompatibility, low toxicity and easy surface modification. However, there are still various limitations including low water solubility and stability, which greatly affect their applications. In addition, some synthetic methods are very complicated and costly. Therefore, huge efforts have been made to improve their properties. This review mainly introduces the strategies for surface modification of gold nanomaterials, such as amines, biological small molecules and organic small molecules as well as the biological applications of these functionalized AuNPs. We aim to provide effective ideas for better functionalization of gold nanomaterials in the future.
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Affiliation(s)
- Bicong Zhou
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Xiaolu Guo
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Naidi Yang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Zhongxi Huang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Lihua Huang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Zhijie Fang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Chengwu Zhang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Lin Li
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
| | - Changmin Yu
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), Nanjing 211816, China.
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6
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Rusakova IL, Rusakov YY. Quantum chemical calculations of 77 Se and 125 Te nuclear magnetic resonance spectral parameters and their structural applications. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:359-407. [PMID: 33095923 DOI: 10.1002/mrc.5111] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/01/2020] [Accepted: 10/07/2020] [Indexed: 06/11/2023]
Abstract
An accurate quantum chemical (QC) modeling of 77 Se and 125 Te nuclear magnetic resonance (NMR) spectra is deeply involved in the NMR structural assignment for selenium and tellurium compounds that are of utmost importance both in organic and inorganic chemistry nowadays due to their huge application potential in many fields, like biology, medicine, and metallurgy. The main interest of this review is focused on the progress in QC computations of 77 Se and 125 Te NMR chemical shifts and indirect spin-spin coupling constants involving these nuclei. Different computational methodologies that have been used to simulate the NMR spectra of selenium and tellurium compounds since the middle of the 1990s are discussed with a strong emphasis on their accuracy. A special accent is placed on the calculations resorting to the relativistic methodologies, because taking into account the relativistic effects appreciably influences the precision of NMR calculations of selenium and, especially, tellurium compounds. Stereochemical applications of quantum chemical calculations of 77 Se and 125 Te NMR parameters are discussed so as to exemplify the importance of integrated approach of experimental and computational NMR techniques.
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Affiliation(s)
- Irina L Rusakova
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russian Federation
| | - Yuriy Yu Rusakov
- A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russian Federation
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7
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Krivdin LB. Recent advances in computational liquid-phase 77Se NMR. RUSSIAN CHEMICAL REVIEWS 2021. [DOI: 10.1070/rcr4960] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This review aims to highlight significant progress in the calculation of 77Se NMR chemical shifts and spin – spin coupling constants involving selenium substantiated with a vast amount of experimental data. The material is arranged in two basic sections: the first one dealing with the calculation of 77Se NMR chemical shifts and the second one dealing with the computation of spin – spin coupling constants involving 77Se nucleus, namely 77Se–1H, 77Se–13C and 77Se–77Se together with some more exotic types of couplings, 77Se – 15N, 77Se–19F, 77Se–29Si and 77Se–31P. A special attention is focused on the stereoelectronic effects involving selenium atom and their manifestation in the 77Se NMR spectra of organoselenium compounds studied with the aid of the modern calculation of 77Se NMR parametres in combination with experimental results.
The bibliography includes 114 references.
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8
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Tiekink ERT. Zero-, one-, two- and three-dimensional supramolecular architectures sustained by Se …O chalcogen bonding: A crystallographic survey. Coord Chem Rev 2021; 427:213586. [PMID: 33100367 PMCID: PMC7568495 DOI: 10.1016/j.ccr.2020.213586] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 09/02/2020] [Indexed: 12/20/2022]
Abstract
The Cambridge Structural Database was evaluated for crystals containing Se…O chalcogen bonding interactions. These secondary bonding interactions are found to operate independently of complementary intermolecular interactions in about 13% of the structures they can potentially form. This number rises significantly when more specific interactions are considered, e.g. Se…O(carbonyl) interactions occur in 50% of cases where they can potentially form. In about 55% of cases, the supramolecular assemblies sustained by Se…O(oxygen) interactions are one-dimensional architectures, with the next most prominent being zero-dimensional assemblies, at 30%.
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Affiliation(s)
- Edward R T Tiekink
- Research Centre for Crystalline Materials, School of Science and Technology, 5 Jalan Universiti, Sunway University, Bandar Sunway, Selangor Darul Ehsan 47500, Malaysia
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Chen Q, Xu S, Lu X, Boeri MV, Pepelyayeva Y, Diaz EL, Soni SD, Allaire M, Forstner MB, Bahnson BJ, Rozovsky S. 77Se NMR Probes the Protein Environment of Selenomethionine. J Phys Chem B 2020; 124:601-616. [PMID: 31846581 DOI: 10.1021/acs.jpcb.9b07466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sulfur is critical for the correct structure and proper function of proteins. Yet, lacking a sensitive enough isotope, nuclear magnetic resonance (NMR) experiments are unable to deliver for sulfur in proteins the usual wealth of chemical, dynamic, and structural information. This limitation can be circumvented by substituting sulfur with selenium, which has similar physicochemical properties and minimal impact on protein structures but possesses an NMR compatible isotope (77Se). Here we exploit the sensitivity of 77Se NMR to the nucleus' chemical milieu and use selenomethionine as a probe for its proteinaceous environment. However, such selenium NMR spectra of proteins currently resist a reliable interpretation because systematic connections between variations of system variables and changes in 77Se NMR parameters are still lacking. To start narrowing this knowledge gap, we report here on a biological 77Se magnetic resonance data bank based on a systematically designed library of GB1 variants in which a single selenomethionine was introduced at different locations within the protein. We recorded the resulting isotropic 77Se chemical shifts and relaxation times for six GB1 variants by solution-state 77Se NMR. For four of the GB1 variants we were also able to determine the chemical shift anisotropy tensor of SeM by solid-state 77Se NMR. To enable interpretation of the NMR data, the structures of five of the GB1 variants were solved by X-ray crystallography to a resolution of 1.2 Å, allowing us to unambiguously determine the conformation of the selenomethionine. Finally, we combine our solution- and solid-state NMR data with the structural information to arrive at general insights regarding the execution and interpretation of 77Se NMR experiments that exploit selenomethionine to probe proteins.
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Affiliation(s)
- Qingqing Chen
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
| | - Shiping Xu
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
| | - Xingyu Lu
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States.,Instrumentation and Service Center for Physical Sciences , Westlake University , Hangzhou , Zhejiang 310024 , China
| | - Michael V Boeri
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States.,Neuroscience Department, Medical Toxicology Research Division , U.S. Army Medical Research Institute of Chemical Defense , 8350 Ricketts Point Road , Gunpowder , Maryland 21010 , United States
| | - Yuliya Pepelyayeva
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States.,Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Elizabeth L Diaz
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
| | - Sunil-Datta Soni
- Neuroscience Department, Medical Toxicology Research Division , U.S. Army Medical Research Institute of Chemical Defense , 8350 Ricketts Point Road , Gunpowder , Maryland 21010 , United States
| | - Marc Allaire
- Berkeley Center for Structural Biology, Molecular Biophysics & Integrated Bioimaging , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Martin B Forstner
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
| | - Brian J Bahnson
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
| | - Sharon Rozovsky
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
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Wei D, Han M, Yu L. Solid-State 77Se NMR of Organoselenium Compounds through Cross Polarization Magic Angle Spinning (CPMAS) Method. Sci Rep 2017; 7:6376. [PMID: 28743927 PMCID: PMC5527004 DOI: 10.1038/s41598-017-06892-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/19/2017] [Indexed: 11/09/2022] Open
Abstract
Characterization of selenium states by 77Se NMR is quite important to provide vital information for mechanism studies in organoselenium-catalyzed reactions. With the development of heterogeneous polymer-supported organoselenium catalysts, the solid state 77Se NMR comes to the spotlight. It is necessary to figure out an advanced protocol that provides good quality spectra within limited time because solid state 77Se NMR measurements are always time consuming due to the long relaxation time and the relatively low sensitivity. Studies on small molecules and several novel polymer-supported organoselenium materials in this article showed that cross polarization (CP) method with the assistance of magic angle spinning (MAS) was more efficient to get high quality spectra than the methods by using single pulse (SP) or high power 1H decoupling (HPHD) combined with MAS. These results lead to a good understanding of the effect of the molecular structure, the heteronuclear coupling, the long-range ordering of the solid (crystal or amorphous), and the symmetry of 77Se on quality of their spectra.
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Affiliation(s)
- Duo Wei
- Testing Center, Yangzhou University, Yangzhou, 225008, China.
| | - Mengting Han
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, China
| | - Lei Yu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, China.
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Murai T, Mizutani T, Ebihara M, Maruyama T. α-Hydroxy and α-Oxo Selenoamides: Synthesis via Nucleophilic Selenocarbamoylation of Carbonyl Compounds and Characterization. J Org Chem 2015; 80:6903-7. [DOI: 10.1021/acs.joc.5b00969] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Toshiaki Murai
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
- JST, ACT-C, 4-1-8 Honcho, Kawaguchi,
Saitama 332-0012, Japan
| | - Tomohiko Mizutani
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
| | - Masahiro Ebihara
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
| | - Toshifumi Maruyama
- Department
of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
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