151
|
Oshita H, Kikuchi M, Mieda K, Ogura T, Yoshimura T, Tani F, Yajima T, Abe H, Mori S, Shimazaki Y. Characterization of Group 10-Metal-p
-Substituted Phenoxyl Radical Complexes with Schiff Base Ligands. ChemistrySelect 2017. [DOI: 10.1002/slct.201701986] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Hiromi Oshita
- Graduate School of Science and Engineering; Ibaraki University; Mito 310-8512 Japan
| | - Misa Kikuchi
- College of Science; Ibaraki University; Mito 310-8512 Japan
| | - Kaoru Mieda
- Picobiology Institute; Graduate School of Life Science; University of Hyogo, Sayo; Hyogo 679-5184 Japan
| | - Takashi Ogura
- Picobiology Institute; Graduate School of Life Science; University of Hyogo, Sayo; Hyogo 679-5184 Japan
| | - Takayoshi Yoshimura
- Graduate School of Science and Engineering; Ibaraki University; Mito 310-8512 Japan
| | - Fumito Tani
- Institute for Materials Chemistry and Engineering; Kyushu University, Nishi-ku; Fukuoka 819-0395 Japan
| | - Tatsuo Yajima
- Faculty of Chemistry; Materials and Bioengineering; Kansai University, Suita; Osaka 564-8680 Japan
| | - Hitoshi Abe
- Photon Factory (PF); Institute of Materials Structure Science (IMSS); High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba; Ibaraki 305-0801 Japan
| | - Seiji Mori
- Graduate School of Science and Engineering; Ibaraki University; Mito 310-8512 Japan
- College of Science; Ibaraki University; Mito 310-8512 Japan
| | | |
Collapse
|
152
|
Kochem A, Molloy JK, Gellon G, Leconte N, Philouze C, Berthiol F, Jarjayes O, Thomas F. A Structurally Characterized Cu III Complex Supported by a Bis(anilido) Ligand and Its Oxidative Catalytic Activity. Chemistry 2017; 23:13929-13940. [PMID: 28742929 DOI: 10.1002/chem.201702010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Indexed: 01/23/2023]
Abstract
Three copper(II) complexes of the (R,R)-N,N'-bis(3,5-di-tert-butyl-2-aminobenzylidene)-1,2-diaminocyclohexane ligand, namely [Cu(N L)], [Cu(N LH)]+ and [Cu(N LH2 )]2+ , were prepared and structurally characterized. In [Cu(N LH2 )]2+ the copper ion lies in an octahedral geometry with the aniline groups coordinated in equatorial positions. In [Cu(N L)] the anilines are deprotonated (anilido moieties) and coordinated to an almost square-planar metal ion. Complex [Cu(N L)] displays two oxidation waves at E1/2ox, 1 =-0.14 V and E1/2ox, 2 =0.36 V vs. Fc+ /Fc in CH2 Cl2 . Complex [Cu(N LH2 )]2+ displays an irreversible oxidation wave at high potential (1.21 V), but shows a readily accessible and reversible metal-centered reduction at E1/2red =-0.67 V (CuII /CuI redox couple). Oxidation of [Cu(N L)] by AgSbF6 produces [Cu(N L)](SbF6 ), which was isolated as single crystals. X-ray structure analysis discloses a contraction of the coordination sphere by 0.05 Å upon oxidation, supporting a metal-centered process. Complex [Cu(N L)](SbF6 ) displays an intense NIR band at 1260 nm corresponding to an anilido-to-copper(III) charge transfer transition. This compound slowly evolves in CH2 Cl2 solution towards [Cu(N LH)](SbF6 ), which is a copper(II) complex comprised of both anilido and aniline groups coordinated to the metal center. The copper(III) complex [Cu(N L)](SbF6 ) is an efficient catalyst for benzyl alcohol oxidation, with 236 TON in 24 h at 298 K, without additives other than oxygen and a base.
Collapse
Affiliation(s)
- Amélie Kochem
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Jennifer K Molloy
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Gisèle Gellon
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Nicolas Leconte
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Christian Philouze
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Florian Berthiol
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Olivier Jarjayes
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| | - Fabrice Thomas
- Département de Chimie Moléculaire, UMR-5250, Université Grenoble Alpes, BP 53, 38041, Grenoble Cedex 9, France
| |
Collapse
|
153
|
|
154
|
Schaftenaar G, Vlieg E, Vriend G. Molden 2.0: quantum chemistry meets proteins. J Comput Aided Mol Des 2017; 31:789-800. [PMID: 28752344 PMCID: PMC5633641 DOI: 10.1007/s10822-017-0042-5] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 07/12/2017] [Indexed: 11/29/2022]
Abstract
Since the first distribution of Molden in 1995 and the publication of the first article about this software in 2000 work on Molden has continued relentlessly. A few of the many improved or fully novel features such as improved and broadened support for quantum chemistry calculations, preparation of ligands for use in drug design related softwares, and working with proteins for the purpose of ligand docking.
Collapse
Affiliation(s)
| | - Elias Vlieg
- Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | | |
Collapse
|
155
|
Sarkar P, Mondal MK, Sarmah A, Maity S, Mukherjee C. An Iminosemiquinone-Coordinated Oxidovanadium(V) Complex: A Combined Experimental and Computational Study. Inorg Chem 2017; 56:8068-8077. [DOI: 10.1021/acs.inorgchem.7b00789] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Prasenjit Sarkar
- Department of Chemistry, Indian Institute of Technology Guwahati (IITG), Guwahati 781039, Assam, India
| | - Manas Kumar Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati (IITG), Guwahati 781039, Assam, India
| | - Amrit Sarmah
- Department
of Molecular Modelling, Institute of Organic Chemistry and Biochemistry ASCR, Flemingovo nám. 2, CZ-16610 Prague 6, Czech Republic
| | - Suvendu Maity
- Department
of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 700103, India
| | - Chandan Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati (IITG), Guwahati 781039, Assam, India
| |
Collapse
|
156
|
Hui J, Bao L, Li S, Zhang Y, Feng Y, Ding L, Ju H. Localized Chemical Remodeling for Live Cell Imaging of Protein-Specific Glycoform. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201703406] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jingjing Hui
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| | - Lei Bao
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| | - Siqiao Li
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| | - Yi Zhang
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| | - Yimei Feng
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| | - Lin Ding
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| | - Huangxian Ju
- State Key Laboratory of Analytical Chemistry for Life Science; School of Chemistry and Chemical Engineering; Nanjing University; Nanjing 210023 P.R. China
| |
Collapse
|
157
|
Hui J, Bao L, Li S, Zhang Y, Feng Y, Ding L, Ju H. Localized Chemical Remodeling for Live Cell Imaging of Protein-Specific Glycoform. Angew Chem Int Ed Engl 2017; 56:8139-8143. [PMID: 28557363 DOI: 10.1002/anie.201703406] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Indexed: 11/07/2022]
Abstract
Live cell imaging of protein-specific glycoforms is important for the elucidation of glycosylation mechanisms and identification of disease states. The currently used metabolic oligosaccharide engineering (MOE) technology permits routinely global chemical remodeling (GCM) for carbohydrate site of interest, but can exert unnecessary whole-cell scale perturbation and generate unpredictable metabolic efficiency issue. A localized chemical remodeling (LCM) strategy for efficient and reliable access to protein-specific glycoform information is reported. The proof-of-concept protocol developed for MUC1-specific terminal galactose/N-acetylgalactosamine (Gal/GalNAc) combines affinity binding, off-on switchable catalytic activity, and proximity catalysis to create a reactive handle for bioorthogonal labeling and imaging. Noteworthy assay features associated with LCM as compared with MOE include minimum target cell perturbation, short reaction timeframe, effectiveness as a molecular ruler, and quantitative analysis capability.
Collapse
Affiliation(s)
- Jingjing Hui
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| | - Lei Bao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| | - Siqiao Li
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| | - Yi Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| | - Yimei Feng
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| | - Lin Ding
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| | - Huangxian Ju
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China
| |
Collapse
|
158
|
Moutet J, Philouze C, du Moulinet d'Hardemare A, Leconte N, Thomas F. Ni(II) Complexes of the Redox-Active Bis(2-aminophenyl)dipyrrin: Structural, Spectroscopic, and Theoretical Characterization of Three Members of an Electron Transfer Series. Inorg Chem 2017; 56:6380-6392. [PMID: 28513171 DOI: 10.1021/acs.inorgchem.7b00433] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The sterically hindered bis(2-aminophenyl)dipyrrin ligand H3NL was prepared. X-ray diffraction discloses a bifurcated hydrogen bonding network involving the dipyrrin and one aniline ring. The reaction of H3NL with one equivalent of nickel(II) in the air produces a paramagnetic neutral complex, which absorbs intensively in the Vis-NIR region. Its electron paramagnetic resonance spectrum displays resonances at g1 = 2.033, g2 = 2.008, and g3 = 1.962 that are reminiscent of an (S = 1/2) system having a predominant organic radical character. Both the structural investigation (X-ray diffraction) and density functional theory calculations on [NiII(NL•)] points to an unprecedented mixed "pyrrolyl-anilinyl" radical character. The neutral complex [NiII(NL•)] exhibits both a reversible oxidation wave at -0.28 V vs Fc+/Fc and a reversible reduction wave at -0.91 V. The anion was found to be highly air-sensitive, but could be prepared by reduction with cobaltocene and structurally characterized. It comprises a Ni(II) ion coordinated to a closed-shell trianionic ligand and hence can be formulated as [NiII(NL)]-. The cation was generated by reacting [NiII(NL•)] with one equivalent of silver hexafluoroantimonate. By X-ray diffraction we established that it contains an oxidized, closed-shell ligand coordinated to a nickel(II) ion. We found that a reliable hallmark for both the oxidation state of the ligand and the extent of delocalization within the series is the bond connecting the dipyrrin and the aniline, which ranges between 1.391 Å (cation) and 1.449 Å (anion). The cation and anion exhibit a rich Vis-NIR spectrum, despite their nonradical nature. The low energy bands correspond to ligand-based electronic excitations. Hence, the HOMO-LUMO gap is small, and the redox processes in the electron transfer series are exclusively ligand-centered.
Collapse
Affiliation(s)
- Jules Moutet
- Département de Chimie Moléculaire - Chimie Inorganique Redox (CIRE) - UMR CNRS 5250, Université Grenoble Alpes , B. P. 53, 38041 Grenoble cedex 9, France
| | - Christian Philouze
- Département de Chimie Moléculaire - Chimie Inorganique Redox (CIRE) - UMR CNRS 5250, Université Grenoble Alpes , B. P. 53, 38041 Grenoble cedex 9, France
| | - Amaury du Moulinet d'Hardemare
- Département de Chimie Moléculaire - Chimie Inorganique Redox (CIRE) - UMR CNRS 5250, Université Grenoble Alpes , B. P. 53, 38041 Grenoble cedex 9, France
| | - Nicolas Leconte
- Département de Chimie Moléculaire - Chimie Inorganique Redox (CIRE) - UMR CNRS 5250, Université Grenoble Alpes , B. P. 53, 38041 Grenoble cedex 9, France
| | - Fabrice Thomas
- Département de Chimie Moléculaire - Chimie Inorganique Redox (CIRE) - UMR CNRS 5250, Université Grenoble Alpes , B. P. 53, 38041 Grenoble cedex 9, France
| |
Collapse
|
159
|
Chaplin AK, Bernini C, Sinicropi A, Basosi R, Worrall JAR, Svistunenko DA. Tyrosine or Tryptophan? Modifying a Metalloradical Catalytic Site by Removal of the Cys-Tyr Cross-Link in the Galactose 6-Oxidase Homologue GlxA. Angew Chem Int Ed Engl 2017; 56:6502-6506. [DOI: 10.1002/anie.201701270] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 03/13/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Amanda K. Chaplin
- School of Biological Sciences; University of Essex; Wivenhoe Park Colchester Essex CO4 3SQ (U K
| | - Caterina Bernini
- Department of Biotechnology, Chemistry and Pharmaceutical Sciences; University of Siena; Via A. Moro, 2 53100 Siena Italy
- CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Adalgisa Sinicropi
- Department of Biotechnology, Chemistry and Pharmaceutical Sciences; University of Siena; Via A. Moro, 2 53100 Siena Italy
- CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Riccardo Basosi
- Department of Biotechnology, Chemistry and Pharmaceutical Sciences; University of Siena; Via A. Moro, 2 53100 Siena Italy
- CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Jonathan A. R. Worrall
- School of Biological Sciences; University of Essex; Wivenhoe Park Colchester Essex CO4 3SQ (U K
| | - Dimitri A. Svistunenko
- School of Biological Sciences; University of Essex; Wivenhoe Park Colchester Essex CO4 3SQ (U K
| |
Collapse
|
160
|
Chaplin AK, Bernini C, Sinicropi A, Basosi R, Worrall JAR, Svistunenko DA. Tyrosine or Tryptophan? Modifying a Metalloradical Catalytic Site by Removal of the Cys-Tyr Cross-Link in the Galactose 6-Oxidase Homologue GlxA. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701270] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Amanda K. Chaplin
- School of Biological Sciences; University of Essex; Wivenhoe Park Colchester Essex CO4 3SQ (U K
| | - Caterina Bernini
- Department of Biotechnology, Chemistry and Pharmaceutical Sciences; University of Siena; Via A. Moro, 2 53100 Siena Italy
- CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Adalgisa Sinicropi
- Department of Biotechnology, Chemistry and Pharmaceutical Sciences; University of Siena; Via A. Moro, 2 53100 Siena Italy
- CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Riccardo Basosi
- Department of Biotechnology, Chemistry and Pharmaceutical Sciences; University of Siena; Via A. Moro, 2 53100 Siena Italy
- CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Jonathan A. R. Worrall
- School of Biological Sciences; University of Essex; Wivenhoe Park Colchester Essex CO4 3SQ (U K
| | - Dimitri A. Svistunenko
- School of Biological Sciences; University of Essex; Wivenhoe Park Colchester Essex CO4 3SQ (U K
| |
Collapse
|
161
|
McCann S, Lumb JP, Arndtsen BA, Stahl SS. Second-Order Biomimicry: In Situ Oxidative Self-Processing Converts Copper(I)/Diamine Precursor into a Highly Active Aerobic Oxidation Catalyst. ACS CENTRAL SCIENCE 2017; 3:314-321. [PMID: 28470049 PMCID: PMC5408333 DOI: 10.1021/acscentsci.7b00022] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Indexed: 05/11/2023]
Abstract
A homogeneous Cu-based catalyst system consisting of [Cu(MeCN)4]PF6, N,N'-di-tert-butylethylenediamine (DBED), and p-(N,N-dimethylamino)pyridine (DMAP) mediates efficient aerobic oxidation of alcohols. Mechanistic study of this reaction shows that the catalyst undergoes an in situ oxidative self-processing step, resulting in conversion of DBED into a nitroxyl that serves as an efficient cocatalyst for aerobic alcohol oxidation. Insights into this behavior are gained from kinetic studies, which reveal an induction period at the beginning of the reaction that correlates with the oxidative self-processing step, EPR spectroscopic analysis of the catalytic reaction mixture, which shows the buildup of the organic nitroxyl species during steady state turnover, and independent synthesis of oxygenated DBED derivatives, which are shown to serve as effective cocatalysts and eliminate the induction period in the reaction. The overall mechanism bears considerable resemblance to enzymatic reactivity. Most notable is the "oxygenase"-type self-processing step that mirrors generation of catalytic cofactors in enzymes via post-translational modification of amino acid side chains. This higher-order function within a synthetic catalyst system presents new opportunities for the discovery and development of biomimetic catalysts.
Collapse
Affiliation(s)
- Scott
D. McCann
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Jean-Philip Lumb
- Department
of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec, H3A 0B8 Canada
- E-mail:
| | - Bruce A. Arndtsen
- Department
of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec, H3A 0B8 Canada
- E-mail:
| | - Shannon S. Stahl
- Department
of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
- E-mail:
| |
Collapse
|
162
|
Quist DA, Diaz DE, Liu JJ, Karlin KD. Activation of dioxygen by copper metalloproteins and insights from model complexes. J Biol Inorg Chem 2017; 22:253-288. [PMID: 27921179 PMCID: PMC5600896 DOI: 10.1007/s00775-016-1415-2] [Citation(s) in RCA: 163] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 11/11/2016] [Indexed: 02/08/2023]
Abstract
Nature uses dioxygen as a key oxidant in the transformation of biomolecules. Among the enzymes that are utilized for these reactions are copper-containing metalloenzymes, which are responsible for important biological functions such as the regulation of neurotransmitters, dioxygen transport, and cellular respiration. Enzymatic and model system studies work in tandem in order to gain an understanding of the fundamental reductive activation of dioxygen by copper complexes. This review covers the most recent advancements in the structures, spectroscopy, and reaction mechanisms for dioxygen-activating copper proteins and relevant synthetic models thereof. An emphasis has also been placed on cofactor biogenesis, a fundamentally important process whereby biomolecules are post-translationally modified by the pro-enzyme active site to generate cofactors which are essential for the catalytic enzymatic reaction. Significant questions remaining in copper-ion-mediated O2-activation in copper proteins are addressed.
Collapse
Affiliation(s)
- David A Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Daniel E Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Jeffrey J Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Kenneth D Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, MD, 21218, USA.
| |
Collapse
|
163
|
Thomas B, Lu X, Birmingham WR, Huang K, Both P, Reyes Martinez JE, Young RJ, Davie CP, Flitsch SL. Application of Biocatalysis to on-DNA Carbohydrate Library Synthesis. Chembiochem 2017; 18:858-863. [PMID: 28127867 DOI: 10.1002/cbic.201600678] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Indexed: 01/14/2023]
Abstract
DNA-encoded libraries are increasingly used for the discovery of bioactive lead compounds in high-throughput screening programs against specific biological targets. Although a number of libraries are now available, they cover limited chemical space due to bias in ease of synthesis and the lack of chemical reactions that are compatible with DNA tagging. For example, compound libraries rarely contain complex biomolecules such as carbohydrates with high levels of functionality, stereochemistry, and hydrophilicity. By using biocatalysis in combination with chemical methods, we aimed to significantly expand chemical space and generate generic libraries with potentially better biocompatibility. For DNA-encoded libraries, biocatalysis is particularly advantageous, as it is highly selective and can be performed in aqueous environments, which is an essential feature for this split-and-mix library technology. In this work, we demonstrated the application of biocatalysis for the on-DNA synthesis of carbohydrate-based libraries by using enzymatic oxidation and glycosylation in combination with traditional organic chemistry.
Collapse
Affiliation(s)
- Baptiste Thomas
- Manchester Institute of Biotechnology and, School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Xiaojie Lu
- Encoded Library Technologies, NCE Molecular Discovery, R&D, Platform Technology & Science, GlaxoSmithKline, 830 Winter Street, Waltham, MA, 02451, USA
| | - William R Birmingham
- Manchester Institute of Biotechnology and, School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Kun Huang
- Manchester Institute of Biotechnology and, School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Peter Both
- Manchester Institute of Biotechnology and, School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Juana Elizabeth Reyes Martinez
- Manchester Institute of Biotechnology and, School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Robert J Young
- Medicinal Chemistry, NCE Molecular Discovery, R&D, Platform Technology and Science, GlaxoSmithKline, GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, SG1 2NY, UK
| | - Christopher P Davie
- Encoded Library Technologies, NCE Molecular Discovery, R&D, Platform Technology & Science, GlaxoSmithKline, 830 Winter Street, Waltham, MA, 02451, USA
| | - Sabine L Flitsch
- Manchester Institute of Biotechnology and, School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| |
Collapse
|
164
|
Active-site maturation and activity of the copper-radical oxidase GlxA are governed by a tryptophan residue. Biochem J 2017; 474:809-825. [DOI: 10.1042/bcj20160968] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 01/02/2017] [Accepted: 01/13/2017] [Indexed: 11/17/2022]
Abstract
GlxA from Streptomyces lividans is a mononuclear copper-radical oxidase and a member of the auxiliary activity family 5 (AA5). Its domain organisation and low sequence homology make it a distinct member of the AA5 family in which the fungal galactose 6-oxidase (Gox) is the best characterised. GlxA is a key cuproenzyme in the copper-dependent morphological development of S. lividans with a function that is linked to the processing of an extracytoplasmic glycan. The catalytic sites in GlxA and Gox contain two distinct one-electron acceptors comprising the copper ion and a 3′-(S-cysteinyl) tyrosine. The latter is formed post-translationally through a covalent bond between a cysteine and a copper-co-ordinating tyrosine ligand and houses a radical. In GlxA and Gox, a second co-ordination sphere tryptophan residue (Trp288 in GlxA) is present, but the orientation of the indole ring differs between the two enzymes, creating a marked difference in the π–π stacking interaction of the benzyl ring with the 3′-(S-cysteinyl) tyrosine. Differences in the spectroscopic and enzymatic activity have been reported between GlxA and Gox with the indole orientation suggested as a reason. Here, we report a series of in vivo and in vitro studies using the W288F and W288A variants of GlxA to assess the role of Trp288 on the morphology, maturation, spectroscopic and enzymatic properties. Our findings point towards a salient role for Trp288 in the kinetics of copper loading and maturation of GlxA, with its presence essential for stabilising the metalloradical site required for coupling catalytic activity and morphological development.
Collapse
|
165
|
Celis AI, Gauss GH, Streit BR, Shisler K, Moraski GC, Rodgers KR, Lukat-Rodgers GS, Peters JW, DuBois JL. Structure-Based Mechanism for Oxidative Decarboxylation Reactions Mediated by Amino Acids and Heme Propionates in Coproheme Decarboxylase (HemQ). J Am Chem Soc 2017; 139:1900-1911. [PMID: 27936663 PMCID: PMC5348300 DOI: 10.1021/jacs.6b11324] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Coproheme decarboxylase catalyzes two sequential oxidative decarboxylations with H2O2 as the oxidant, coproheme III as substrate and cofactor, and heme b as the product. Each reaction breaks a C-C bond and results in net loss of hydride, via steps that are not clear. Solution and solid-state structural characterization of the protein in complex with a substrate analog revealed a highly unconventional H2O2-activating distal environment with the reactive propionic acids (2 and 4) on the opposite side of the porphyrin plane. This suggested that, in contrast to direct C-H bond cleavage catalyzed by a high-valent iron intermediate, the coproheme oxidations must occur through mediating amino acid residues. A tyrosine that hydrogen bonds to propionate 2 in a position analogous to the substrate in ascorbate peroxidase is essential for both decarboxylations, while a lysine that salt bridges to propionate 4 is required solely for the second. A mechanism is proposed in which propionate 2 relays an oxidizing equivalent from a coproheme compound I intermediate to the reactive deprotonated tyrosine, forming Tyr•. This residue then abstracts a net hydrogen atom (H•) from propionate 2, followed by migration of the unpaired propionyl electron to the coproheme iron to yield the ferric harderoheme and CO2 products. A similar pathway is proposed for decarboxylation of propionate 4, but with a lysine residue as an essential proton shuttle. The proposed reaction suggests an extended relay of heme-mediated e-/H+ transfers and a novel route for the conversion of carboxylic acids to alkenes.
Collapse
Affiliation(s)
- Arianna I. Celis
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| | - George H. Gauss
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| | - Bennett R. Streit
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| | - Krista Shisler
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| | - Garrett C. Moraski
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| | - Kenton R. Rodgers
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND 58108-6050
| | - Gudrun S. Lukat-Rodgers
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND 58108-6050
| | - John W. Peters
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| | - Jennifer L. DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717-3400
| |
Collapse
|
166
|
Elwell CE, Gagnon NL, Neisen BD, Dhar D, Spaeth AD, Yee GM, Tolman WB. Copper-Oxygen Complexes Revisited: Structures, Spectroscopy, and Reactivity. Chem Rev 2017; 117:2059-2107. [PMID: 28103018 PMCID: PMC5963733 DOI: 10.1021/acs.chemrev.6b00636] [Citation(s) in RCA: 454] [Impact Index Per Article: 64.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A longstanding research goal has been to understand the nature and role of copper-oxygen intermediates within copper-containing enzymes and abiological catalysts. Synthetic chemistry has played a pivotal role in highlighting the viability of proposed intermediates and expanding the library of known copper-oxygen cores. In addition to the number of new complexes that have been synthesized since the previous reviews on this topic in this journal (Mirica, L. M.; Ottenwaelder, X.; Stack, T. D. P. Chem. Rev. 2004, 104, 1013-1046 and Lewis, E. A.; Tolman, W. B. Chem. Rev. 2004, 104, 1047-1076), the field has seen significant expansion in the (1) range of cores synthesized and characterized, (2) amount of mechanistic work performed, particularly in the area of organic substrate oxidation, and (3) use of computational methods for both the corroboration and prediction of proposed intermediates. The scope of this review has been limited to well-characterized examples of copper-oxygen species but seeks to provide a thorough picture of the spectroscopic characteristics and reactivity trends of the copper-oxygen cores discussed.
Collapse
Affiliation(s)
- Courtney E Elwell
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Nicole L Gagnon
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Benjamin D Neisen
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Debanjan Dhar
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Andrew D Spaeth
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Gereon M Yee
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - William B Tolman
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
167
|
Rajmohan R, Ayaz Ahmed KB, Sangeetha S, Anbazhagan V, Vairaprakash P. C–H oxidation and chelation of a dipyrromethane mediated rapid colorimetric naked-eye Cu(ii) chemosensor. Analyst 2017; 142:3346-3351. [DOI: 10.1039/c7an01052d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Selective C–H oxidation and chelation of DPMs mediated by copper is demonstrated and utilized in the development of a rapid colorimetric naked-eye Cu(ii) chemosensor.
Collapse
Affiliation(s)
- Rajamani Rajmohan
- Department of Chemistry
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur
- India
| | - Khan Behlol Ayaz Ahmed
- Department of Chemistry
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur
- India
| | - Sampathkumar Sangeetha
- Department of Chemistry
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur
- India
| | - Veerappan Anbazhagan
- Department of Chemistry
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur
- India
| | | |
Collapse
|
168
|
Zhan G, Zhong W, Wei Z, Liu Z, Liu X. Roles of phenol groups and auxiliary ligand of copper(ii) complexes with tetradentate ligands in the aerobic oxidation of benzyl alcohol. Dalton Trans 2017. [DOI: 10.1039/c7dt01716b] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Mimics structurally assembled to form the metal center of GOase. The phenol group(s) and substituent (R) and the auxiliary ligand (L) of the mimics significantly affect catalysis during the aerobic oxidation of benzyl alcohol.
Collapse
Affiliation(s)
- Guangli Zhan
- School of Chemistry
- Nanchang University
- Nanchang
- China
| | - Wei Zhong
- College of Biological
- Chemical Sciences and Engineering
- Jiaxing University
- Jiaxing
- China
| | - Zhenhong Wei
- School of Chemistry
- Nanchang University
- Nanchang
- China
| | - Zhenzhen Liu
- School of Chemistry
- Nanchang University
- Nanchang
- China
| | - Xiaoming Liu
- College of Biological
- Chemical Sciences and Engineering
- Jiaxing University
- Jiaxing
- China
| |
Collapse
|
169
|
Rosnes MH, Sheptyakov D, Franz A, Frontzek M, Dietzel PDC, Georgiev PA. On the elusive nature of oxygen binding at coordinatively unsaturated 3d transition metal centers in metal–organic frameworks. Phys Chem Chem Phys 2017; 19:26346-26357. [DOI: 10.1039/c7cp05119k] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Low and ambient temperature binding of oxygen, O2, in MOF-74, CPO-27-M (M = Mn, Co, Ni, Cu, Zn) framework materials remains in the physisorption regime, with energetics very similar to that of nitrogen, N2, sorption.
Collapse
Affiliation(s)
- Mali H. Rosnes
- Department of Chemistry
- University of Bergen
- N-5020 Bergen
- Norway
| | - Denis Sheptyakov
- Laboratory for Neutron Scattering
- Paul Scherrer Institute
- CH-5232 Villigen
- Switzerland
| | - Alexandra Franz
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH
- Hahn-Meitner-Platz 114109 Berlin
- Germany
| | - Matthias Frontzek
- Quantum Condensed Matter Division
- Oak Ridge National Laboratory
- 37831 Oak Ridge
- USA
| | | | - Peter A. Georgiev
- Department of Chemistry
- University of Milan
- I-20133 Milan
- Italy
- Faculty of Physics
| |
Collapse
|
170
|
Bury CS, Carmichael I, Garman EF. OH cleavage from tyrosine: debunking a myth. JOURNAL OF SYNCHROTRON RADIATION 2017; 24:7-18. [PMID: 28009542 PMCID: PMC5182017 DOI: 10.1107/s1600577516016775] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/19/2016] [Indexed: 05/09/2023]
Abstract
During macromolecular X-ray crystallography experiments, protein crystals held at 100 K have been widely reported to exhibit reproducible bond scission events at doses on the order of several MGy. With the objective to mitigate the impact of radiation damage events on valid structure determination, it is essential to correctly understand the radiation chemistry mechanisms at play. OH-cleavage from tyrosine residues is regularly cited as amongst the most available damage pathways in protein crystals at 100 K, despite a lack of widespread reports of this phenomenon in protein crystal radiation damage studies. Furthermore, no clear mechanism for phenolic C-O bond cleavage in tyrosine has been reported, with the tyrosyl radical known to be relatively robust and long-lived in both aqueous solutions and the solid state. Here, the initial findings of Tyr -OH group damage in a myrosinase protein crystal have been reviewed. Consistent with that study, at increasing doses, clear electron density loss was detectable local to Tyr -OH groups. A systematic investigation performed on a range of protein crystal damage series deposited in the Protein Data Bank has established that Tyr -OH electron density loss is not generally a dominant damage pathway in protein crystals at 100 K. Full Tyr aromatic ring displacement is here proposed to account for instances of observable Tyr -OH electron density loss, with the original myrosinase data shown to be consistent with such a damage model. Systematic analysis of the effects of other environmental factors, including solvent accessibility and proximity to disulfide bonds or hydrogen bond interactions, is also presented. Residues in known active sites showed enhanced sensitivity to radiation-induced disordering, as has previously been reported.
Collapse
Affiliation(s)
- Charles S. Bury
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Ian Carmichael
- Notre Dame Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Elspeth F Garman
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| |
Collapse
|
171
|
Gupta P, Diefenbach M, Holthausen MC, Förster M. Copper-Mediated Selective Hydroxylation of a Non-activated C−H Bond in Steroids: A DFT Study of Schönecker's Reaction. Chemistry 2016; 23:1427-1435. [DOI: 10.1002/chem.201604829] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Puneet Gupta
- Institut für Anorganische und Analytische Chemie; Johann Wolfgang Goethe-Universität Frankfurt; Max-von-Laue-Straße 7 60438 Frankfurt am Main Germany
- Present address: Max-Planck-Institut für Kohlenforschung; Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Martin Diefenbach
- Institut für Anorganische und Analytische Chemie; Johann Wolfgang Goethe-Universität Frankfurt; Max-von-Laue-Straße 7 60438 Frankfurt am Main Germany
| | - Max C. Holthausen
- Institut für Anorganische und Analytische Chemie; Johann Wolfgang Goethe-Universität Frankfurt; Max-von-Laue-Straße 7 60438 Frankfurt am Main Germany
| | - Moritz Förster
- Institut für Anorganische und Analytische Chemie; Johann Wolfgang Goethe-Universität Frankfurt; Max-von-Laue-Straße 7 60438 Frankfurt am Main Germany
| |
Collapse
|
172
|
Unjaroen D, Swart M, Browne WR. Electrochemical Polymerization of Iron(III) Polypyridyl Complexes through C–C Coupling of Redox Non-innocent Phenolato Ligands. Inorg Chem 2016; 56:470-479. [DOI: 10.1021/acs.inorgchem.6b02378] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Duenpen Unjaroen
- Stratingh Institute
for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi (IQCC),
Departament de Química, Universitat de Girona, Campus Montilivi, 17003 Girona, Catalonia, Spain
- ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain
| | - Wesley R. Browne
- Stratingh Institute
for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| |
Collapse
|
173
|
Cuzan O, Kochem A, Simaan AJ, Bertaina S, Faure B, Robert V, Shova S, Giorgi M, Maffei M, Réglier M, Orio M. Oxidative DNA Cleavage Promoted by a Phenoxyl‐Radical Copper(II) Complex. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201601001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Olesea Cuzan
- Aix Marseille Université CNRS Centrale Marseille Marseille France
- Institute of Chemistry Academy of Sciences of Moldova 3, Academiei str. MD 2028 Chisinau Republic of Moldova
| | - Amélie Kochem
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| | - A. Jalila Simaan
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| | | | - Bruno Faure
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| | - Viviane Robert
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| | - Sergiu Shova
- Institute of Macromolecular Chemistry “Petru Poni” 41A Grigore Ghica Voda Alley 700487 Iasi Romania
| | - Michel Giorgi
- Aix Marseille Univ CNRS Centrale Marseille Marseille France[‡]For his outstanding contribution to inorganic and coordination chemistry
| | - Michel Maffei
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| | - Marius Réglier
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| | - Maylis Orio
- Aix Marseille Université CNRS Centrale Marseille Marseille France
| |
Collapse
|
174
|
Evaluations of AMBER force field parameters by MINA approach for copper-based nucleases. Struct Chem 2016. [DOI: 10.1007/s11224-016-0764-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
175
|
Copper(II) complex of a Schiff base of dehydroacetic acid: Characterization and aerobic oxidation of benzyl alcohol. INORG CHEM COMMUN 2016. [DOI: 10.1016/j.inoche.2016.07.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
176
|
Cowley RE, Cirera J, Qayyum MF, Rokhsana D, Hedman B, Hodgson KO, Dooley DM, Solomon EI. Structure of the Reduced Copper Active Site in Preprocessed Galactose Oxidase: Ligand Tuning for One-Electron O 2 Activation in Cofactor Biogenesis. J Am Chem Soc 2016; 138:13219-13229. [PMID: 27626829 DOI: 10.1021/jacs.6b05792] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Galactose oxidase (GO) is a copper-dependent enzyme that accomplishes 2e- substrate oxidation by pairing a single copper with an unusual cysteinylated tyrosine (Cys-Tyr) redox cofactor. Previous studies have demonstrated that the post-translational biogenesis of Cys-Tyr is copper- and O2-dependent, resulting in a self-processing enzyme system. To investigate the mechanism of cofactor biogenesis in GO, the active-site structure of Cu(I)-loaded GO was determined using X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy, and density-functional theory (DFT) calculations were performed on this model. Our results show that the active-site tyrosine lowers the Cu potential to enable the thermodynamically unfavorable 1e- reduction of O2, and the resulting Cu(II)-O2•- is activated toward H atom abstraction from cysteine. The final step of biogenesis is a concerted reaction involving coordinated Tyr ring deprotonation where Cu(II) coordination enables formation of the Cys-Tyr cross-link. These spectroscopic and computational results highlight the role of the Cu(I) in enabling O2 activation by 1e- and the role of the resulting Cu(II) in enabling substrate activation for biogenesis.
Collapse
Affiliation(s)
- Ryan E Cowley
- Department of Chemistry, Stanford University , Stanford, California 94305, United States
| | - Jordi Cirera
- Department of Chemistry, Stanford University , Stanford, California 94305, United States
| | - Munzarin F Qayyum
- Department of Chemistry, Stanford University , Stanford, California 94305, United States
| | - Dalia Rokhsana
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States
| | - Britt Hedman
- Department of Chemistry, Stanford University , Stanford, California 94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University , Menlo Park, California 94025, United States
| | - Keith O Hodgson
- Department of Chemistry, Stanford University , Stanford, California 94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University , Menlo Park, California 94025, United States
| | - David M Dooley
- Department of Chemistry and Biochemistry, Montana State University , Bozeman, Montana 59717, United States.,University of Rhode Island , Kingston, Rhode Island 02881, United States
| | - Edward I Solomon
- Department of Chemistry, Stanford University , Stanford, California 94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University , Menlo Park, California 94025, United States
| |
Collapse
|
177
|
Synthesis, characterization, crystal structure, redox-reactivity and antiproliferative activity studies of Cu(II) and Pd(II) complexes with F, CF3 bearing 3,5-di-tert-butylsalicylaldimines. Polyhedron 2016. [DOI: 10.1016/j.poly.2016.03.061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
178
|
Dhara AK, Kumar K, Kumari S, Singh UP, Ghosh K. Non-Innocent Property of Tridentate Ligand in Novel Cobalt Complex : Crystal Structure and Evidences for Cobalt(II) Phenoxyl Radical Complex Formation. ChemistrySelect 2016. [DOI: 10.1002/slct.201600647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Ashish Kumar Dhara
- Department of Chemistry; Indian Institute of Technology Roorkee, Roorkee; Uttrakhand-247667 India
| | - Kapil Kumar
- Department of Chemistry; Indian Institute of Technology Roorkee, Roorkee; Uttrakhand-247667 India
| | - Sheela Kumari
- Department of Chemistry; Indian Institute of Technology Roorkee, Roorkee; Uttrakhand-247667 India
| | - Udai P. Singh
- Department of Chemistry; Indian Institute of Technology Roorkee, Roorkee; Uttrakhand-247667 India
| | - Kaushik Ghosh
- Department of Chemistry; Indian Institute of Technology Roorkee, Roorkee; Uttrakhand-247667 India
| |
Collapse
|
179
|
Vu VV, Marletta MA. Starch-degrading polysaccharide monooxygenases. Cell Mol Life Sci 2016; 73:2809-19. [PMID: 27170366 PMCID: PMC11108391 DOI: 10.1007/s00018-016-2251-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 01/08/2023]
Abstract
Polysaccharide degradation by hydrolytic enzymes glycoside hydrolases (GHs) is well known. More recently, polysaccharide monooxygenases (PMOs, also known as lytic PMOs or LPMOs) were found to oxidatively degrade various polysaccharides via a copper-dependent hydroxylation. PMOs were previously thought to be either GHs or carbohydrate binding modules (CBMs), and have been re-classified in carbohydrate active enzymes (CAZY) database as auxiliary activity (AA) families. These enzymes include cellulose-active fungal PMOs (AA9, formerly GH61), chitin- and cellulose-active bacterial PMOs (AA10, formerly CBM33), and chitin-active fungal PMOs (AA11). These PMOs significantly boost the activity of GHs under industrially relevant conditions, and thus have great potential in the biomass-based biofuel industry. PMOs that act on starch are the latest PMOs discovered (AA13), which has expanded our perspectives in PMOs studies and starch degradation. Starch-active PMOs have many common structural features and biochemical properties of the PMO superfamily, yet differ from other PMO families in several important aspects. These differences likely correlate, at least in part, to the differences in primary and higher order structures of starch and cellulose, and chitin. In this review we will discuss the discovery, structural features, biochemical and biophysical properties, and possible biological functions of starch-active PMOs, as well as their potential application in the biofuel, food, and other starch-based industries. Important questions regarding various aspects of starch-active PMOs and possible economical driving force for their future studies will also be highlighted.
Collapse
Affiliation(s)
- Van V Vu
- NTT Hi-Tech Institute (NHTI), Nguyen Tat Thanh University, 298-300A Nguyen Tat Thanh Street, Ward 13, District 4, Ho Chi Minh City, Vietnam
| | - Michael A Marletta
- Department of Chemistry and Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA, 94720-3220, USA.
| |
Collapse
|
180
|
Cooperative electrocatalytic alcohol oxidation with electron-proton-transfer mediators. Nature 2016; 535:406-10. [DOI: 10.1038/nature18008] [Citation(s) in RCA: 301] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 04/13/2016] [Indexed: 12/23/2022]
|
181
|
Henthorn JT, Agapie T. Modulation of Proton-Coupled Electron Transfer through Molybdenum-Quinonoid Interactions. Inorg Chem 2016; 55:5337-42. [PMID: 27227812 DOI: 10.1021/acs.inorgchem.6b00331] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An expanded series of π-bound molybdenum-quinonoid complexes supported by pendant phosphines has been synthesized. These compounds formally span three protonation-oxidation states of the quinonoid fragment (catechol, semiquinone, quinone) and two different oxidation states of the metal (Mo(0), Mo(II)), notably demonstrating a total of two protons and four electrons accessible in the system. Previously, the reduced Mo(0)-catechol complex 1 and its reaction with dioxygen to yield the two-proton/two-electron oxidized Mo(0)-quinone compound 4 was explored, while, herein, the expansion of the series to include the two-electron oxidized Mo(II)-catechol complex 2, the one-proton/two-electron oxidized Mo-semiquinone complex 3, and the two-proton/four-electron oxidized Mo(II)-quinone complexes 5 and 6 is reported. Transfer of multiple equivalents of protons and electrons from the Mo(0) and Mo(II) catechol complexes, 1 and 2, to H atom acceptor TEMPO suggests the presence of weak O-H bonds. Although thermochemical analyses are hindered by the irreversibility of the electrochemistry of the present compounds, the reactivity observed suggests weaker O-H bonds compared to the free catechol, indicating that proton-coupled electron transfer can be facilitated significantly by the π-bound metal center.
Collapse
Affiliation(s)
- Justin T Henthorn
- Division of Chemistry and Chemical Engineering, California Institute of Technology , 1200 East California Boulevard, MC 127-72, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology , 1200 East California Boulevard, MC 127-72, Pasadena, California 91125, United States
| |
Collapse
|
182
|
Porter TR, Capitao D, Kaminsky W, Qian Z, Mayer JM. Synthesis, Radical Reactivity, and Thermochemistry of Monomeric Cu(II) Alkoxide Complexes Relevant to Cu/Radical Alcohol Oxidation Catalysis. Inorg Chem 2016; 55:5467-75. [PMID: 27171230 DOI: 10.1021/acs.inorgchem.6b00491] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Two new monomeric Cu(II) alkoxide complexes were prepared and fully characterized as models for intermediates in copper/radical mediated alcohol oxidation catalysis: Tp(tBuR)Cu(II)OCH2CF3 with Tp(tBu) = hydro-tris(3-tert-butyl-pyrazol-1-yl)borate 1 or Tp(tBuMe) = hydro-tris(3-tert-butyl-5-methyl-pyrazol-1-yl)borate 2. These complexes were made as models for potential intermediates in enzymatic and synthetic catalytic cycles for alcohol oxidation. However, the alkoxide ligands are not readily oxidized by loss of H; instead, these complexes were found to be hydrogen atom acceptors. They oxidize the hydroxylamine TEMPOH, 2,4,6-tri-t-butylphenol, and 1,4-cyclohexadiene to the nitroxyl radical, phenoxyl radical, and benzene, with formation of HOCH2CF3 (TFE) and the Cu(I) complexes Tp(tBuR)Cu(I)-MeCN in dichloromethane/1% MeCN or 1/2 [Tp(tBuR)Cu(I)]2 in toluene. On the basis of thermodynamics and kinetics arguments, these reactions likely proceed through concerted proton-electron transfer mechanisms. Thermochemical analyses give lower limits for the "effective bond dissociation free energies (BDFE)" of the O-H bonds in 1/2[Tp(tBuR)Cu(I)]2 + TFE and upper limits for the free energies associated with alkoxide oxidations via hydrogen atom transfer (effective alkoxide α-C-H BDFEs). These values are summations of the free energies of multiple chemical steps, which include the energetically favorable formation of 1/2[Tp(tBuR)Cu(I)]2. The effective alkoxide α-C-H bonds are very weak, BDFE ≤ 38 ± 4 kcal mol(-1) for 1 and ≤44 ± 5 kcal mol(-1) for 2 (gas-phase estimates), because C-H homolysis is thermodynamically coupled to one electron transfer to Cu(II) as well as the favorable formation of the 1/2[Tp(tBuR)Cu(I)]2 dimer. Treating 1 with the H atom acceptor (t)Bu3ArO(•) did not result in the expected alkoxide oxidation to an aldehyde, but rather net 2,2,2-trifluoroethoxyl radical transfer occurred to generate an unusual 2-substituted dienone-ether product. Treating 2 with (t)Bu3ArO(•) gives no reaction, despite evidence that overall ligand oxidation and formation of 1/2[Tp(tBuMe)Cu(I)]2 is significantly exoergic. The origin of this lack of reactivity may be due to insufficient weakening of the alcohol α-C-H bond upon complexation to copper.
Collapse
Affiliation(s)
- Thomas R Porter
- Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195, United States
| | - Dany Capitao
- Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195, United States
| | - Werner Kaminsky
- Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195, United States
| | - Zhaoshen Qian
- Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195, United States
| | - James M Mayer
- Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195, United States
| |
Collapse
|
183
|
Rakshit R, Mukherjee C. Secondary Interactions versus Intramolecular π–π Interactions in CuII–Diradical Complexes. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Richa Rakshit
- Department of Chemistry Indian Institute of Technology Guwahati 781029 Guwahati Assam India
| | - Chandan Mukherjee
- Department of Chemistry Indian Institute of Technology Guwahati 781029 Guwahati Assam India
| |
Collapse
|
184
|
|
185
|
Ando K, Nakazawa J, Hikichi S. Synthesis, Characterization and Aerobic Alcohol Oxidation Catalysis of Palladium(II) Complexes with a Bis(imidazolyl)borate Ligand. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600206] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Kenta Ando
- Department of Material and Life ChemistryFaculty of EngineeringKanagawa University3‐27‐1 Rokkakubashi, Kanagawa‐ku221‐8686YokohamaJapan
| | - Jun Nakazawa
- Department of Material and Life ChemistryFaculty of EngineeringKanagawa University3‐27‐1 Rokkakubashi, Kanagawa‐ku221‐8686YokohamaJapan
| | - Shiro Hikichi
- Department of Material and Life ChemistryFaculty of EngineeringKanagawa University3‐27‐1 Rokkakubashi, Kanagawa‐ku221‐8686YokohamaJapan
| |
Collapse
|
186
|
MONDAL PALASH, PARUA SANKARPRASAD, PATTANAYAK POULAMI, DAS UTTAM, CHATTOPADHYAY SURAJIT. Synthesis and structure of copper(II) complexes: Potential cyanide sensor and oxidase model. J CHEM SCI 2016. [DOI: 10.1007/s12039-016-1063-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
187
|
Hayes EC, Porter TR, Barrows CJ, Kaminsky W, Mayer JM, Stoll S. Electronic Structure of a Cu(II)-Alkoxide Complex Modeling Intermediates in Copper-Catalyzed Alcohol Oxidations. J Am Chem Soc 2016; 138:4132-45. [PMID: 26907976 PMCID: PMC4988936 DOI: 10.1021/jacs.5b13088] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In the copper-catalyzed oxidation of alcohols to aldehydes, a Cu(II)-alkoxide (Cu(II)-OR) intermediate is believed to modulate the αC-H bond strength of the deprotonated substrate to facilitate the oxidation. As a structural model for these intermediates, we characterized the electronic structure of the stable compound Tp(tBu)Cu(II)(OCH2CF3) (Tp(tBu) = hydro-tris(3-tert-butyl-pyrazolyl)borate) and investigated the influence of the trifluoroethoxide ligand on the electronic structure of the complex. The compound exhibits an electron paramagnetic resonance (EPR) spectrum with an unusually large gzz value of 2.44 and a small copper hyperfine coupling Azz of 40 × 10(-4) cm(-1) (120 MHz). Single-crystal electron nuclear double resonance (ENDOR) spectra show that the unpaired spin population is highly localized on the copper ion (≈68%), with no more than 15% on the ethoxide oxygen. Electronic absorption and magnetic circular dichroism (MCD) spectra show weak ligand-field transitions between 5000 and 12,000 cm(-1) and an intense ethoxide-to-copper charge transfer (LMCT) transition at 24,000 cm(-1), resulting in the red color of this complex. Resonance Raman (rR) spectroscopy reveals a Cu-O stretch mode at 592 cm(-1). Quantum chemical calculations support the interpretation and assignment of the experimental data. Compared to known Cu(II)-thiolate and Cu(II)-alkylperoxo complexes from the literature, we found an increased σ interaction in the Cu(II)-OR bond that results in the spectroscopic features. These insights lay the basis for further elucidating the mechanism of copper-catalyzed alcohol oxidations.
Collapse
Affiliation(s)
- Ellen C. Hayes
- Department of Chemistry, Box 351700, University of Washington, Seattle, WA 98195
| | | | - Charles J. Barrows
- Department of Chemistry, Box 351700, University of Washington, Seattle, WA 98195
| | - Werner Kaminsky
- Department of Chemistry, Box 351700, University of Washington, Seattle, WA 98195
| | | | - Stefan Stoll
- Department of Chemistry, Box 351700, University of Washington, Seattle, WA 98195
| |
Collapse
|
188
|
Sun Y, Tang H, Chen K, Hu L, Yao J, Shaik S, Chen H. Two-State Reactivity in Low-Valent Iron-Mediated C–H Activation and the Implications for Other First-Row Transition Metals. J Am Chem Soc 2016; 138:3715-30. [DOI: 10.1021/jacs.5b12150] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yihua Sun
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Hao Tang
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Kejuan Chen
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Lianrui Hu
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Jiannian Yao
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Sason Shaik
- Institute
of Chemistry and the Lise Meitner-Minerva Center for Computational
Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel
| | - Hui Chen
- Beijing
National Laboratory for Molecular Sciences (BNLMS), Key Laboratory
of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| |
Collapse
|
189
|
Horak KT, Agapie T. Dioxygen Reduction by a Pd(0)–Hydroquinone Diphosphine Complex. J Am Chem Soc 2016; 138:3443-52. [DOI: 10.1021/jacs.5b12928] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kyle T. Horak
- Division of Chemistry and
Chemical Engineering, California Institute of Technology, 1200 East
California Boulevard MC 127-72, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and
Chemical Engineering, California Institute of Technology, 1200 East
California Boulevard MC 127-72, Pasadena, California 91125, United States
| |
Collapse
|
190
|
Djebli Y, Bencharif M, Rabilloud F. Theoretical study of bis(N-(5-(4-methoxyphenyl)-1,3,4-oxadiazol-2-yl)ethanimidamidato)M complexes (M = Co, Ni, Cu, Zn, Pd, Cd): Structural, electronic and optical properties. COMPUT THEOR CHEM 2016. [DOI: 10.1016/j.comptc.2016.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
191
|
Importance of chelate–chelate stacking interactions in crystal structures of square pyramidal copper(II) complexes with two distinct chelating bidentate ligands. Inorganica Chim Acta 2016. [DOI: 10.1016/j.ica.2015.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
192
|
Neidlinger A, Förster C, Heinze K. How Hydrogen Bonds Affect Reactivity and Intervalence Charge Transfer in Ferrocenium-Phenolate Radicals. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201501471] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
193
|
Skara G, Gimferrer M, De Proft F, Salvador P, Pinter B. Scrutinizing the Noninnocence of Quinone Ligands in Ruthenium Complexes: Insights from Structural, Electronic, Energy, and Effective Oxidation State Analyses. Inorg Chem 2016; 55:2185-99. [DOI: 10.1021/acs.inorgchem.5b02543] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Gabriella Skara
- Eenheid Algemene Chemie (ALGC), Member
of the QCMM VUB-UGent Alliance Research Group, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Marti Gimferrer
- Institut de Química
Computacional i Catàlisi (IQCC) i Department de Química, Universitat de Girona, 17071 Girona, Spain
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC), Member
of the QCMM VUB-UGent Alliance Research Group, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Pedro Salvador
- Institut de Química
Computacional i Catàlisi (IQCC) i Department de Química, Universitat de Girona, 17071 Girona, Spain
| | - Balazs Pinter
- Eenheid Algemene Chemie (ALGC), Member
of the QCMM VUB-UGent Alliance Research Group, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| |
Collapse
|
194
|
Eberle B, Damjanović M, Enders M, Leingang S, Pfisterer J, Krämer C, Hübner O, Kaifer E, Himmel HJ. Radical Monocationic Guanidino-Functionalized Aromatic Compounds (GFAs) as Bridging Ligands in Dinuclear Metal Acetate Complexes: Synthesis, Electronic Structure, and Magnetic Coupling. Inorg Chem 2016; 55:1683-96. [DOI: 10.1021/acs.inorgchem.5b02614] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Benjamin Eberle
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Marko Damjanović
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Markus Enders
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Simone Leingang
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Jessica Pfisterer
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Christoph Krämer
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Olaf Hübner
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Elisabeth Kaifer
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Hans-Jörg Himmel
- Ruprecht-Karls-Universität Heidelberg, Anorganisch-Chemisches Institut, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| |
Collapse
|
195
|
Ghorai S, Sarmah A, Roy RK, Tiwari A, Mukherjee C. Effect of Geometrical Distortion on the Electronic Structure: Synthesis and Characterization of Monoradical-Coordinated Mononuclear Cu(II) Complexes. Inorg Chem 2016; 55:1370-80. [PMID: 26812584 DOI: 10.1021/acs.inorgchem.5b01257] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ligand H3Sami(Mixed(tBu)) was composed of two different compartments, a redox-active 2-aminophenol and a salen salicylidene. Both compartments were linked via a benzyl linker. The ligand reacted with CuCl2·2H2O under air in the presence of Et3N and provided the corresponding monoradical-coordinated mononuclear Cu(II) complex (1). Complex 1, in solution, reacted with air and provided complex 2 via ligand-centered oxygenation at the benzyl-CH2 position. Both complexes were characterized via IR, mass spectrometry, X-ray single-crystal diffraction, variable-temperature magnetic susceptibility, cyclic voltammograms (CVs), and UV-vis/NIR spectroscopic techniques. X-ray crystallographic analyses clearly showed almost equally distorted square planar geometry around the Cu(II) atom in both complexes. However, the bending of the radical-containing C6 ring compared to the N1-Cu1-O1 plane was different in both complexes. While complex 1 was paramagnetic and showed a ferromagnetic coupling between the d(x(2)-y(2)) magnetic orbital of Cu(II) ion and the p(z) orbital of coordinated π-radical, complex 2 was diamagnetic by experiencing a strong antiferromagnetic coupling between the two magnetic orbitals. UV-vis/NIR spectra of the complexes were dominated by charge-transfer transitions. CVs of the complexes showed two reversible one-electron oxidations and one reversible one-electron reduction. E(1/2)(ox2) and E(1/2)(red1) potentials were different in both complexes, while E(1/2)(ox1) values were almost the same and the process corresponded to the formation of phenoxyl radical. Theoretical studies were also performed to understand the magnetic coupling phenomena, and TD-DFT calculations were employed for the assignment of charge-transfer absorption bands.
Collapse
Affiliation(s)
- Samir Ghorai
- Department of Chemistry, Indian Institute of Technology Guwahati , Guwahati, 781039 Assam, India
| | - Amrit Sarmah
- Department of Chemistry, Birla Institute of Technology and Science (BITS) , Pilani, 333031 Rajasthan, India
| | - Ram Kinkar Roy
- Department of Chemistry, Birla Institute of Technology and Science (BITS) , Pilani, 333031 Rajasthan, India
| | - Archana Tiwari
- Department of Physics, School of Physical Sciences, Sikkim University , Gangtok 737102 Sikkim, India
| | - Chandan Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati , Guwahati, 781039 Assam, India
| |
Collapse
|
196
|
Electrocatalytic O2
Reduction at a Bio-inspired Mononuclear Copper Phenolato Complex Immobilized on a Carbon Nanotube Electrode. Angew Chem Int Ed Engl 2016; 55:2517-20. [DOI: 10.1002/anie.201509593] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 11/23/2015] [Indexed: 12/21/2022]
|
197
|
Gentil S, Serre D, Philouze C, Holzinger M, Thomas F, Le Goff A. Electrocatalytic O2
Reduction at a Bio-inspired Mononuclear Copper Phenolato Complex Immobilized on a Carbon Nanotube Electrode. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201509593] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Solène Gentil
- Département de Chimie Moléculaire, UMR CNRS 5250; Univ. Grenoble Alpes; 570 rue de la Chimie, B. P. 53 38041 Grenoble cedex 9 France
| | - Doti Serre
- Département de Chimie Moléculaire, UMR CNRS 5250; Univ. Grenoble Alpes; 570 rue de la Chimie, B. P. 53 38041 Grenoble cedex 9 France
| | - Christian Philouze
- Département de Chimie Moléculaire, UMR CNRS 5250; Univ. Grenoble Alpes; 570 rue de la Chimie, B. P. 53 38041 Grenoble cedex 9 France
| | - Michael Holzinger
- Département de Chimie Moléculaire, UMR CNRS 5250; Univ. Grenoble Alpes; 570 rue de la Chimie, B. P. 53 38041 Grenoble cedex 9 France
| | - Fabrice Thomas
- Département de Chimie Moléculaire, UMR CNRS 5250; Univ. Grenoble Alpes; 570 rue de la Chimie, B. P. 53 38041 Grenoble cedex 9 France
| | - Alan Le Goff
- Département de Chimie Moléculaire, UMR CNRS 5250; Univ. Grenoble Alpes; 570 rue de la Chimie, B. P. 53 38041 Grenoble cedex 9 France
| |
Collapse
|
198
|
Herasymchuk K, Chiang L, Hayes CE, Brown ML, Ovens JS, Patrick BO, Leznoff DB, Storr T. Synthesis and electronic structure determination of uranium(vi) ligand radical complexes. Dalton Trans 2016; 45:12576-86. [DOI: 10.1039/c6dt02089e] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pentagonal bipyramidal uranyl (UO22+) complexes of salen ligands were prepared and the electronic structure of the one-electron oxidized species[1a–c]+were investigated in solution.
Collapse
Affiliation(s)
| | - Linus Chiang
- Department of Chemistry
- Simon Fraser University
- Burnaby
- Canada
| | | | | | | | - Brian O. Patrick
- Department of Chemistry
- University of British Columbia
- Vancouver
- Canada
| | | | - Tim Storr
- Department of Chemistry
- Simon Fraser University
- Burnaby
- Canada
| |
Collapse
|
199
|
Wang L, Bie Z, Shang S, Lv Y, Li G, Niu J, Gao S. Bioinspired aerobic oxidation of alcohols with a bifunctional ligand based on bipyridine and TEMPO. RSC Adv 2016. [DOI: 10.1039/c6ra05536b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new bifunctional ligand bearing bipyridine and TEMPO in combination with copper for the oxidation of alcohols was developed.
Collapse
Affiliation(s)
- Lianyue Wang
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian National Laboratory for Clean Energy (DNL)
- Dalian
- China
| | - Zhixing Bie
- Henan Key Laboratory of Polyoxometalate Chemistry
- Institute of Molecular and Crystal Engineering
- College of Chemistry and Chemical Engineering
- Henan University
- Kaifeng
| | - Sensen Shang
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian National Laboratory for Clean Energy (DNL)
- Dalian
- China
| | - Ying Lv
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian National Laboratory for Clean Energy (DNL)
- Dalian
- China
| | - Guosong Li
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian National Laboratory for Clean Energy (DNL)
- Dalian
- China
| | - Jingyang Niu
- Henan Key Laboratory of Polyoxometalate Chemistry
- Institute of Molecular and Crystal Engineering
- College of Chemistry and Chemical Engineering
- Henan University
- Kaifeng
| | - Shuang Gao
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian National Laboratory for Clean Energy (DNL)
- Dalian
- China
| |
Collapse
|
200
|
Dhara AK, Singh UP, Ghosh K. Radical pathways and O2 participation in benzyl alcohol oxidation, and catechol and o-aminophenol oxidase activity studies with novel zinc complexes: an experimental and theoretical investigation. Inorg Chem Front 2016. [DOI: 10.1039/c6qi00356g] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Diphenoxo bridged dinuclear zinc complexes were found to be capable of oxidation of benzyl alcohol, catechol and o-aminophenol.
Collapse
Affiliation(s)
- Ashish Kumar Dhara
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Uttrakhand
- India
| | - Udai P. Singh
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Uttrakhand
- India
| | - Kaushik Ghosh
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Uttrakhand
- India
| |
Collapse
|