101
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Hong W, Lee H, Noh TH, Jung OS. Direct anion effects on coordination polymerizations: construction and physicochemical properties of 1D, 2D, and 3D copper(ii) coordination polymers containing 1,3,5-tris(isonicotinoyloxyethyl)cyanurate. Dalton Trans 2013; 42:11092-9. [DOI: 10.1039/c3dt51124c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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102
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Majumder S, Mondal S, Lemoine P, Mohanta S. Dinuclear mixed-valence CoIIICoII complexes derived from a macrocyclic ligand: unique example of a CoIIICoII complex showing catecholase activity. Dalton Trans 2013; 42:4561-9. [DOI: 10.1039/c2dt32629a] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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103
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Seth P, Ghosh A. A mixed-valence Mn6 cluster exhibiting self-assembled vesicular structure and catecholase-like activity in solution state. RSC Adv 2013. [DOI: 10.1039/c3ra22710c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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104
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Moon SY, Noh TH, Jung OS. Insight into the crystallization process: relationships between crystal structures and properties of copper(ii) coordination polymers containing dimethylbis(4-pyridyl)silane. CrystEngComm 2013. [DOI: 10.1039/c3ce40257f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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105
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Lee H, Noh TH, Jung OS. Reversible supra-channel effects: 3D kagome structure and catalysis via a molecular array of 1D coordination polymers. Chem Commun (Camb) 2013; 49:9182-4. [DOI: 10.1039/c3cc45587d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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106
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Mandal S, Mukherjee J, Lloret F, Mukherjee R. Modeling tyrosinase and catecholase activity using new m-Xylyl-based ligands with bidentate alkylamine terminal coordination. Inorg Chem 2012. [PMID: 23194383 DOI: 10.1021/ic3013848] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chemical model systems possessing the reactivity aspects of both tyrosinase and catechol oxidase are presented. Using two m-xylyl-based ligands providing bidentate alkylamine terminal coordination, 1,3-bis[(N,N-dimethylaminoethyl)aminomethyl]benzene (L(H,H)) and 1,3-bis[(N,N,N'-trimethylaminoethyl)aminomethyl]benzene (L(Me,Me)), four new dicopper(I) complexes, [Cu(I)(2)(L(H,H))(MeCN)(4)][ClO(4)](2) (1), [Cu(I)(2)(L(H,H))(PPh(3))(2)(MeCN)(2)][ClO(4)](2) (2), [Cu(I)(2)(L(Me,Me))(MeCN)(2)][ClO(4)](2) (3), and [Cu(I)(2)(L(Me,Me))(PPh(3))(2)][ClO(4)](2) (4), have been synthesized and characterized. Complex 2 has been structurally characterized. Reaction of the dicopper(I) complex 3(2+) with dioxygen at 183 K generates putative bis(μ-oxo)dicopper(III) intermediate (absorption spectroscopy). Oxygenation of 1 and 3 brings about m-xylyl-ring hydroxylation (monooxygenase-like activity), with a noticeable color change from pale-yellow to dark green. The presence of phenoxo- and hydroxo-bridges in the end products [Cu(II)(2)(L(H,H)-O)(OH)(MeCN)(2)][ClO(4)](2) (5) and [Cu(II)(2)(L(Me,Me)-O)(OH)(OClO(3))][ClO(4)]·MeCN(6) has been authenticated by structural characterization. Oxygenation of 3 afforded not only the green complex 6 isolation but also a blue complex [Cu(II)(2)(L(Me,Me))(OH)(2)][ClO(4)](2) (7). Variable temperature magnetic susceptibility measurements on 5 and 6 establish that the Cu(II) centers are strongly antiferromagnetically coupled [singlet-triplet energy gap (J) = -528 cm(-1) (5) and -505 cm(-1) (6)]. The abilities of phenoxo- and hydroxo-bridged dicopper(II) complexes 5 and 6, the previously reported complex [Cu(II)(2)(L(1)-O)(OH)(OClO(3))(2)]·1.5H(2)O (8) (L(1)-OH = 1,3-bis[(2-dimethylaminoethyl)iminomethyl]phenol), and [Cu(II)(2)(L(2)-O)(OH)(OClO(3))()][ClO(4)]() (9) (L(2)-OH = 1,3-[(2-dimethylaminoethyl)iminomethyl][(N,N,N'-trimethyl)aminoethyl]-4-methylphenol) have been examined to catalyze the oxidation of catechol to quinone (catecholase activity of tyrosinase and catechol oxidase-like activity) by employing the model substrate 3,5-di-tert-butylcatechol. Saturation kinetic studies have been performed on these systems to arrive at the following reactivity order [k(cat)/K(M) (catalytic efficiency) × 10(-3) (M(-1) h(-1))]: 470 (6) > 367 (5) > 128 (9) > 90 (8).
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Affiliation(s)
- Sukanta Mandal
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
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107
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Biswas A, Das LK, Drew MGB, Diaz C, Ghosh A. Insertion of a hydroxido bridge into a diphenoxido dinuclear copper(II) complex: drastic change of the magnetic property from strong antiferromagnetic to ferromagnetic and enhancement in the catecholase activity. Inorg Chem 2012; 51:10111-21. [PMID: 22963285 DOI: 10.1021/ic300319s] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A diphenoxido-bridged dinuclear copper(II) complex, [Cu(2)L(2)(ClO(4))(2)] (1), has been synthesized using a tridentate reduced Schiff base ligand, 2-[[2-(diethylamino)ethylamino]methyl]phenol (HL). The addition of triethylamine to the methanolic solution of this complex produced a novel triple bridged (double phenoxido and single hydroxido) dinuclear copper(II) complex, [Cu(2)L(2)(OH)]ClO(4) (2). Both complexes 1 and 2 were characterized by X-ray structural analyses, variable-temperature magnetic susceptibility measurements, and spectroscopic methods. In 1, the two phenoxido bridges are equatorial-equatorial and the species shows strong antiferromagnetic coupling with J = -615.6(6.1) cm(-1). The inclusion of the equatorial-equatorial hydroxido bridge in 2 changes the Cu···Cu distance from 3.018 Å (avg.) to 2.798 Å (avg.), the positions of the phenoxido bridges to axial-equatorial, and the magnetic coupling to ferromagnetic with J = 50.1(1.4) cm(-1). Using 3,5-di-tert-butylcatechol as the substrate, the catecholase activity of the complexes has been studied in a methanol solution; compound 2 shows higher catecholase activity (k(cat) = 233.4 h(-1)) than compound 1 (k(cat) = 93.6 h(-1)). Both complexes generate identical species in solution, and they are interconvertible simply by changing the pH of their solutions. The higher catecholase activity of 2 seems to be due to the presence of the OH group, which increases the pH of its solution.
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Affiliation(s)
- Apurba Biswas
- Department of Chemistry, University College of Science, University of Calcutta, 92 APC Road, Kolkata 700 009, India
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108
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109
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Comba P, Martin B, Muruganantham A, Straub J. Structure, Bonding, and Catecholase Mechanism of Copper Bispidine Complexes. Inorg Chem 2012; 51:9214-25. [DOI: 10.1021/ic3004917] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Peter Comba
- Universität Heidelberg, Anorganisch-Chemisches
Institut, INF 270, D-69120 Heidelberg, Germany
| | - Bodo Martin
- Universität Heidelberg, Anorganisch-Chemisches
Institut, INF 270, D-69120 Heidelberg, Germany
| | - Amsaveni Muruganantham
- Universität Heidelberg, Anorganisch-Chemisches
Institut, INF 270, D-69120 Heidelberg, Germany
| | - Johannes Straub
- Universität Heidelberg, Anorganisch-Chemisches
Institut, INF 270, D-69120 Heidelberg, Germany
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110
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Guha A, Chattopadhyay T, Paul ND, Mukherjee M, Goswami S, Mondal TK, Zangrando E, Das D. Radical Pathway in Catecholase Activity with Zinc-Based Model Complexes of Compartmental Ligands. Inorg Chem 2012; 51:8750-9. [DOI: 10.1021/ic300400v] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Averi Guha
- Department
of Chemistry, University of Calcutta, 92,
A. P. C. Road, Kolkata
700 009, India
| | | | - Nanda Dulal Paul
- Department
of Inorganic Chemistry, Indian Association for the Cultivation of Science,
Jadavpur, Kolkata 700 032, India
| | - Madhuparna Mukherjee
- Department
of Chemistry, University of Calcutta, 92,
A. P. C. Road, Kolkata
700 009, India
| | - Somen Goswami
- Department
of Chemistry, University of Calcutta, 92,
A. P. C. Road, Kolkata
700 009, India
| | - Tapan Kumar Mondal
- Department of Chemistry, Jadavpur University, Jadavpur, Kolkata 700 032, India
| | - Ennio Zangrando
- Dipartimento di Scienze Chimiche
e Farmaceutiche, University of Trieste,
Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Debasis Das
- Department
of Chemistry, University of Calcutta, 92,
A. P. C. Road, Kolkata
700 009, India
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111
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Martínez A, Membrillo I, Ugalde-Saldívar VM, Gasque L. Dinuclear Copper Complexes with Imidazole Derivative Ligands: A Theoretical Study Related to Catechol Oxidase Activity. J Phys Chem B 2012; 116:8038-44. [DOI: 10.1021/jp300444m] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ana Martínez
- Instituto de Investigaciones
en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior S. N., Ciudad Universitaria
CP 04510, México D.F. México
| | - Ingrid Membrillo
- Departamento de Química
Inorgánica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria
04510, México DF, México
| | - Victor M. Ugalde-Saldívar
- Departamento de Química
Inorgánica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria
04510, México DF, México
| | - Laura Gasque
- Departamento de Química
Inorgánica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria
04510, México DF, México
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112
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Biswas A, Das LK, Drew MGB, Aromí G, Gamez P, Ghosh A. Synthesis, Crystal Structures, Magnetic Properties and Catecholase Activity of Double Phenoxido-Bridged Penta-Coordinated Dinuclear Nickel(II) Complexes Derived from Reduced Schiff-Base Ligands: Mechanistic Inference of Catecholase Activity. Inorg Chem 2012; 51:7993-8001. [DOI: 10.1021/ic202748m] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Apurba Biswas
- Department
of Chemistry, University
College of Science, University of Calcutta, 92 APC Road, Kolkata 700 009, India
| | - Lakshmi Kanta Das
- Department
of Chemistry, University
College of Science, University of Calcutta, 92 APC Road, Kolkata 700 009, India
| | - Michael G. B. Drew
- School of Chemistry, The University of Reading, P.O BOX 224, Whiteknights,
Reading RG 66AD, United Kingdom
| | - Guillem Aromí
- Departament de Química
Inorgànica, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Patrick Gamez
- Departament de Química
Inorgànica, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys, 23, 08010 Barcelona, Spain
| | - Ashutosh Ghosh
- Department
of Chemistry, University
College of Science, University of Calcutta, 92 APC Road, Kolkata 700 009, India
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113
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Kar P, Haldar R, Gómez-García CJ, Ghosh A. Antiferromagnetic Porous Metal–Organic Framework Containing Mixed-Valence [MnII4MnIII2(μ4-O)2]10+ Units with Catecholase Activity and Selective Gas Adsorption. Inorg Chem 2012; 51:4265-73. [DOI: 10.1021/ic2027362] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Paramita Kar
- Department of Chemistry, University
College of Science, University of Calcutta, 92, APC Road, Kolkata-700 009, India
| | - Ritesh Haldar
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore
560064, India
| | - Carlos J. Gómez-García
- Instituto de
Ciencia Molecular
(ICMol), C/Catedrático José Beltrán 2, Parque
Científico, Universidad de Valencia, 46980 Paterna, Valencia, Spain
| | - Ashutosh Ghosh
- Department of Chemistry, University
College of Science, University of Calcutta, 92, APC Road, Kolkata-700 009, India
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114
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Osório REHMB, Peralta RA, Bortoluzzi AJ, de Almeida VR, Szpoganicz B, Fischer FL, Terenzi H, Mangrich AS, Mantovani KM, Ferreira DEC, Rocha WR, Haase W, Tomkowicz Z, Anjos AD, Neves A. Synthesis, Magnetostructural Correlation, and Catalytic Promiscuity of Unsymmetric Dinuclear Copper(II) Complexes: Models for Catechol Oxidases and Hydrolases. Inorg Chem 2012; 51:1569-89. [DOI: 10.1021/ic201876k] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | | | | | | | - Antonio S. Mangrich
- Departamento de
Química, Universidade Federal do Paraná, 81531-970 Curitiba, Paraná, Brazil
| | - Karen Mary Mantovani
- Departamento de
Química, Universidade Federal do Paraná, 81531-970 Curitiba, Paraná, Brazil
| | - Dalva E. C. Ferreira
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Campus Universitário
Pampulha, 31270-901 Pampulha, Belo Horizonte, Minas Gerais, Brazil
| | - Willian R. Rocha
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, Campus Universitário
Pampulha, 31270-901 Pampulha, Belo Horizonte, Minas Gerais, Brazil
| | - Wolfgang Haase
- Institut für Physikalishe
Chemie, Technische Universität Darmstadt, Petersenstraße 20, D-64287-Darmstadt, Germany
| | - Zbigniew Tomkowicz
- Institut für Physikalishe
Chemie, Technische Universität Darmstadt, Petersenstraße 20, D-64287-Darmstadt, Germany
- Institute of Physics, Reymonta
4, Jagiellonian University, PL-30-059 Krakow,
Poland
| | - Ademir dos Anjos
- Universidade Estadual de Mato Grosso do Sul, 79950-000 Unidade Universitária
de Naviraí, Mato Grosso do Sul, Brazil
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115
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Rey NA, Neves A, Bortoluzzi AJ, Haase W, Tomkowicz Z. Doubly phenoxo–hydroxo-bridged dicopper(ii) complexes: individual contributions of the bridges to antiferromagnetic coupling based on two related biomimetic models for catechol oxidases. Dalton Trans 2012; 41:7196-200. [DOI: 10.1039/c2dt30419h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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116
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Marion R, Saleh NM, Le Poul N, Floner D, Lavastre O, Geneste F. Rate enhancement of the catechol oxidase activity of a series of biomimetic monocopper(ii) complexes by introduction of non-coordinating groups in N-tripodal ligands. NEW J CHEM 2012. [DOI: 10.1039/c2nj40265c] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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117
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Magnetic and catalytic properties of a new copper(II)–Schiff base 2D coordination polymer formed by connected helical chains. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.06.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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118
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Characterization and catechole oxidase activity of a family of copper complexes coordinated by tripodal pyrazole-based ligands. J Inorg Biochem 2011; 105:1391-7. [PMID: 21946439 DOI: 10.1016/j.jinorgbio.2011.07.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 07/25/2011] [Accepted: 07/26/2011] [Indexed: 11/22/2022]
Abstract
A family of tripodal pyrazole-based ligands has been synthesized by a condensation reaction between 1-hydroxypyrazoles and aminoalcohols. The diversity was introduced both on the substituents of the pyrazole ring and on the side chain. The corresponding copper(II) complexes have been prepared by reaction with CuCl(2) in tetrahydrofuran. They have been characterized by EPR, UV spectroscopy and cyclic voltammetry. The absence of the half-field splitting signals in EPR suggests that the complex exists in solution as mononuclear species. The influence of substituents and side chain of the tripodal ligand on the catecholase activity of the complexes was studied. The reaction rate depends on two factors. First, the presence of an oxygen atom in the third position of the side chain should be avoided to keep the effectiveness of the reaction. Second, the electronic and steric effects of substituents on the pyrazole ring strongly affect the catalytic activity of the complex. Thus, best results were obtained with complexes containing unsubstituted pyrazole based-ligands. Kinetic investigations with the best catalyst based on the Michaelis-Menten model show that the catalytic activity of the mononuclear complex is close to that of some dicopper complexes described in literature.
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119
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Majumder S, Sarkar S, Sasmal S, Sañudo EC, Mohanta S. Heterobridged dinuclear, tetranuclear, dinuclear-based 1-d, and heptanuclear-based 1-D complexes of copper(II) derived from a dinucleating ligand: syntheses, structures, magnetochemistry, spectroscopy, and catecholase activity. Inorg Chem 2011; 50:7540-54. [PMID: 21776948 DOI: 10.1021/ic200409d] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The work in this paper presents syntheses, characterization, crystal structures, variable-temperature/field magnetic properties, catecholase activity, and electrospray ionization mass spectroscopic (ESI-MS positive) study of five copper(II) complexes of composition [Cu(II)(2)L(μ(1,1)-NO(3))(H(2)O)(NO(3))](NO(3)) (1), [{Cu(II)(2)L(μ-OH)(H(2)O)}(μ-ClO(4))](n)(ClO(4))(n) (2), [{Cu(II)(2)L(NCS)(2)}(μ(1,3)-NCS)](n) (3), [{Cu(II)(2)L(μ(1,1)-N(3))(ClO(4))}(2)(μ(1,3)-N(3))(2)] (4), and [{Cu(II)(2)L(μ-OH)}{Cu(II)(2)L(μ(1,1)-N(3))}{Cu(II)(μ(1,1)-N(3))(4)(dmf)}{Cu(II)(2)(μ(1,1)-N(3))(2)(N(3))(4)}](n)·ndmf (5), derived from a new compartmental ligand 2,6-bis[N-(2-pyridylethyl)formidoyl]-4-ethylphenol, which is the 1:2 condensation product of 4-ethyl-2,6-diformylphenol and 2-(2-aminoethyl)pyridine. The title compounds are either of the following nuclearities/topologies: dinuclear (1), dinuclear-based one-dimensional (2 and 3), tetranuclear (4), and heptanuclear-based one-dimensional (5). The bridging moieties in 1-5 are as follows: μ-phenoxo-μ(1,1)-nitrate (1), μ-phenoxo-μ-hydroxo and μ-perchlorate (2), μ-phenoxo and μ(1,3)-thiocyanate (3), μ-phenoxo-μ(1,1)-azide and μ(1,3)-azide (4), μ-phenoxo-μ-hydroxo, μ-phenoxo-μ(1,1)-azide, and μ(1,1)-azide (5). All the five compounds exhibit overall antiferromagnetic interaction. The J values in 1-4 have been determined (-135 cm(-1) for 1, -298 cm(-1) for 2, -105 cm(-1) for 3, -119.5 cm(-1) for 4). The pairwise interactions in 5 have been evaluated qualitatively to result in S(T) = 3/2 spin ground state, which has been verified by magnetization experiment. Utilizing 3,5-di-tert-butyl catechol (3,5-DTBCH(2)) as the substrate, catecholase activity of all the five complexes have been checked. While 1 and 3 are inactive, complexes 2, 4, and 5 show catecholase activity with turn over numbers 39 h(-1) (for 2), 40 h(-1) (for 4), and 48 h(-1) (for 5) in dmf and 167 h(-1) (for 2) and 215 h(-1) (for 4) in acetonitrile. Conductance of the dmf solution of the complexes has been measured, revealing that bridging moieties and nuclearity have been almost retained in solution. Electrospray ionization mass (ESI-MS positive) spectra of complexes 1, 2, and 4 have been recorded in acetonitrile solutions and the positive ions have been well characterized. ESI-MS positive spectrum of complex 2 in presence of 3,5-DTBCH(2) have also been recorded and, interestingly, a positive ion [Cu(II)(2)L(μ-3,5-DTBC(2-))(3,5-DTBCH(-))Na(I)](+) has been identified.
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Affiliation(s)
- Samit Majumder
- Department of Chemistry, University of Calcutta, 92 A. P. C. Road, Kolkata 700 009, India
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120
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Giri S, Biswas S, Drew MG, Ghosh A, Saha SK. Structure and magnetic properties of a tetranuclear Cu(II) complex containing the 2-(pyridine-2-yliminomethyl)-phenol ligand. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2010.12.069] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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121
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Thermodynamic, spectroscopic studies and catechol oxidase activity of copper (II) complexes with amphiphilic d-galacturonic acid derived ligands. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2010.11.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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122
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Ozay H, Baran Y. Synthesis, complex formation kinetics and thermodynamic study of some acyclic polyamine and N2O2 ligands with copper(II). J COORD CHEM 2010. [DOI: 10.1080/00958972.2010.535144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Hava Ozay
- a Department of Chemistry, Art and Science Faculty , Onsekiz Mart University , 17100 Canakkale , Turkey
| | - Yakup Baran
- a Department of Chemistry, Art and Science Faculty , Onsekiz Mart University , 17100 Canakkale , Turkey
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123
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Kapoor P, Pannu APS, Sharma M, Hundal MS, Kapoor R, Corbella M, Aliaga-Alcalde N. Syntheses, X-ray crystal structure and magnetic studies of a new dinuclear CuII complex, [Cu2(μ-Cl)2L2Cl2]·2CH3CN, L: N,N,N′,N′-tetraisopropylpyridine-2,6-dicarboxamide. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2010.07.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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124
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Peralta RA, Bortoluzzi AJ, Szpoganicz B, Brandão TAS, Castellano EE, de Oliveira MB, Severino PC, Terenzi H, Neves A. Catecholase and DNase activities of copper(II) complexes containing phenolate-type ligands. J PHYS ORG CHEM 2010. [DOI: 10.1002/poc.1779] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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125
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Bhardwaj VK, Aliaga-Alcalde N, Corbella M, Hundal G. Synthesis, crystal structure, spectral and magnetic studies and catecholase activity of copper(II) complexes with di- and tri-podal ligands. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2009.09.041] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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126
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Mandal S, Balamurugan V, Lloret F, Mukherjee R. Syntheses, X-ray Structures, and Physicochemical Properties of Phenoxo-Bridged Dinuclear Nickel(II) Complexes: Kinetics of Transesterification of 2-Hydroxypropyl-p-nitrophenylphosphate. Inorg Chem 2009; 48:7544-56. [DOI: 10.1021/ic8018937] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sukanta Mandal
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
| | - V. Balamurugan
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
| | - Francesc Lloret
- Departament de Química Inorgànica/Instituto de Ciencia Molecular (ICMOL), Universitat de València, Polígono de la Coma, s/n, 46980-Paterna (València), Spain
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127
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Coordination characteristics of di-O-picolyl derivative of 1,1′-methylene-bis(2-naphthol): First crystal structure of a monomeric Cu(II) complex of bis{2-[(pyridin-2-yl)methoxy] naphthalen-1-yl}methane. Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2008.12.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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128
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Sreenivasulu B. Diphenoxo-Bridged Copper(II) Complexes of Reduced Schiff Base Ligands as Functional Models for Catechol Oxidase. Aust J Chem 2009. [DOI: 10.1071/ch09263] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The design and development of synthetic analogues for the active dicopper(ii) sites of catechol oxidase, with the help of binucleating ligands in particular, is an attractive strategy to generate relevant information on structure–function relationships. Dicopper(ii) complexes of different yet closely related series of reduced Schiff base ligands (N-(2-hydroxybenzyl)-amino acids; N-(2-hydroxybenzyl)-amino amides, N-(2-hydroxybenzyl)-aminomethane or ethanesulfonic acids, and N-(2-hydroxy-5-substituted-benzyl)-cyclopentane or hexanecarboxylic acids) derived from various substituted salicylaldehydes and natural or unnatural amino acids or amides explored as functional models for the Type 3 copper enzyme catecholase oxidase are reviewed in the present paper. The catalytic activity of different series of dicopper(ii) complexes to oxidize the model substrate 3,5-di-tert-butylcatechol to the corresponding 3,5-di-tert-butylquinone is discussed with respect to the various ligand properties such as the length and chelating ability of the amino acid side-arm of the ligands, conformation of the ligand, nature of the donor groups on the amino acid backbone and role of different para-substituents. This article provides a short review summarizing the trend observed in the catecholase activity of different series of dicopper(ii) complexes investigated in our laboratory.
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Banu KS, Chattopadhyay T, Banerjee A, Mukherjee M, Bhattacharya S, Patra GK, Zangrando E, Das D. Mono- and dinuclear manganese(III) complexes showing efficient catechol oxidase activity: syntheses, characterization and spectroscopic studies. Dalton Trans 2009:8755-64. [DOI: 10.1039/b902498k] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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130
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Banu KS, Chattopadhyay T, Banerjee A, Bhattacharya S, Suresh E, Nethaji M, Zangrando E, Das D. Catechol Oxidase Activity of a Series of New Dinuclear Copper(II) Complexes with 3,5-DTBC and TCC as Substrates: Syntheses, X-ray Crystal Structures, Spectroscopic Characterization of the Adducts and Kinetic Studies. Inorg Chem 2008; 47:7083-93. [DOI: 10.1021/ic701332w] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kazi Sabnam Banu
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Tanmay Chattopadhyay
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Arpita Banerjee
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Santanu Bhattacharya
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Eringathodi Suresh
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Munirathinam Nethaji
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Ennio Zangrando
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
| | - Debasis Das
- Department of Chemistry, University of Calcutta, 92, A. P. C. Road, Kolkata −700 009, India, Department of Chemistry, Maharaja Manindra Chandra College, Kolkata - 700 003, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G. B. Marg, Bhavnagar-364 002, India, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore- 560 012, India, and Dipartimento di Scienze Chimiche, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy
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131
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Synthesis and properties of (2-pyridyl)alkylamine- and (2-pyridyl)alkylamine–amide-coordinated copper(II) complexes: Structures and non-covalent interactions. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2008.01.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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132
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A dicopper complex with distant metal centers. Structure, magnetic properties, electrochemistry and catecholase activity. J Inorg Biochem 2008; 102:1227-35. [DOI: 10.1016/j.jinorgbio.2007.12.032] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2007] [Revised: 11/15/2007] [Accepted: 12/17/2007] [Indexed: 11/19/2022]
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133
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Banerjee A, Sarkar S, Chopra D, Colacio E, Rajak KK. Binuclear copper(II) complexes with N4O3 coordinating heptadentate ligand: synthesis, structure, magnetic properties, density-functional theory study, and catecholase activity. Inorg Chem 2008; 47:4023-31. [PMID: 18412334 DOI: 10.1021/ic7015935] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The N4O3 coordinating heptadentate ligand afforded binuclear complex [Cu 2(H 2L)(mu-OH)](ClO4)2 (1) and [Cu2(L)(H2O)2]PF6 (2). In complex 1, two copper ions are held together by mu-phenoxo and mu-hydroxo bridges, whereas in complex 2, the copper centers are connected only by a mu-phenoxo bridge. In 1, both the Cu(II) centers have square pyramidal geometry (tau=0.01-0.205), whereas in the case of 2, one Cu(II) center has square pyramidal (tau=0.2517) and other one has square based pyramidal distorted trigonal bipyramidal (tau=0.54) geometry. Complexes 1 and 2 show an strong intramolecular and very weak antiferromagnetic interaction, respectively. Density-functional theory calculations were performed to establish the magneto structural correlation between the two paramagnetic copper(II) centers. Both of the complexes display a couple of one-electron reductive responses near -0.80 and -1.10 V. The complexes show significant catalytic activity at pH 8.5 on the oxidation of 3,5-di- tert-butylcatechol (3,5-DTBC) to 3,5-di- tert-butylquinone (3,5-DTBQ), and the activity measured in terms of kcat=29-37 h(-1).
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Affiliation(s)
- Atanu Banerjee
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700 032, India
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134
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Mijangos E, Reedijk J, Gasque L. Copper(ii) complexes of a polydentate imidazole-based ligand. pH effect on magnetic coupling and catecholase activity. Dalton Trans 2008:1857-63. [PMID: 18369492 DOI: 10.1039/b714283h] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A potentially dodecadentate N8O4-donor ligand obtained from 2,2'-biimidazole and l-valine and its tetranuclear Cu(ii) complexes in different degrees of protonation were characterized by chemical and spectroscopic methods. The extensive solution studies performed reveal that the rise in pH media leads successively to the formation of imidazolato (pKa(1) and pKa(2) and hydroxido (pKa(3) and pKa(4)) bridges. A frozen solution EPR study shows a decrease in the signal intensity until an EPR silent spectrum is observed, upon increasing the basicity of the solution. The catalytic performance of the oxidation of 3,5-di-tert-butylcatechol to its corresponding quinone was studied using UV-Vis-NIR absorption spectroscopic methods in CH3CN-H2O and in CH3OH-H2O at pH = 7.5, 8.0 and 8.5. A marked increase in activity, consistent with the formation of the hydroxide bridged species, is observed at pH = 8.5 in both solvent mixtures, but the activity is significantly higher in CH3OH-H2O.
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Affiliation(s)
- Edgar Mijangos
- Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México D. F, 04510, México
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135
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Structural and spectroscopic studies of a model for catechol oxidase. J Biol Inorg Chem 2008; 13:499-510. [DOI: 10.1007/s00775-007-0334-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 12/10/2007] [Indexed: 10/22/2022]
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136
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Grigoropoulou G, Christoforidis KC, Louloudi M, Deligiannakis Y. Structure-catalytic function relationship of SiO2-immobilized mononuclear Cu complexes: an EPR study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:10407-18. [PMID: 17764200 DOI: 10.1021/la700815d] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Mononuclear CuL and Cu(2L) complexes, where L is propyl-thiazol-2-ylmethylene-amine, covalently immobilized onto SiO2, can catalyze efficiently the oxidation of 3,5-di-t-butylcatechol (DTBC) to 3,5-di-t-butylquinone (DTBQ) by utilizing ambient O2 as oxidant. By increasing the loading of L on SiO2, the DTBQ formation can be improved up to 400% vs the homogeneous catalyst. Equally important is however that grafting per se at low loading is not adequate for an improved catalytic activity. Appropriate loadings have to be achieved, which then may result in significant catalytic performance. Based on EPR spectroscopy a theoretical method is developed, eq A12, for spin-spin distance estimation in heterogeneously dispersed surface complexes. Practical rules including error estimates are provided. By applying this method to the [SiO2-CuL] catalysts it is shown that mononuclear copper complexes fixed on SiO2 with Cu...Cu distances as short as 4.9 +/- 0.3 A are responsible for the improved catalytic activity. The present results demonstrate that mononuclear Cu complexes can have considerable catecholase activity, if the proper geometrical proximity can be fixed. Grafting on SiO2 may be an efficient method for engineering catalysts with improved performance.
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Affiliation(s)
- Georgia Grigoropoulou
- Department of Environmental and Natural Resources Management, University of Ioannina, Seferi 2, 30100 Agrinio, Greece
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137
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Wiśniewska J, Kita P, Wrzeszcz G. Kinetic and ESR studies of the CuII-halides mediated oxidation of promazine by dioxygen in acidic aqueous solutions. TRANSIT METAL CHEM 2007. [DOI: 10.1007/s11243-007-0219-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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138
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Ackermann J, Buchler S, Meyer F. Structure–activity correlations in highly preorganized dicopper catechol oxidase model systems. CR CHIM 2007. [DOI: 10.1016/j.crci.2006.09.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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139
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140
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Zhang GF, Zhou QP, Dou YL, Yin MH, Wang Y. Synthesis, structural characterization and catalytic activities of dicopper(II) complexes derived from tridentate pyrazole-based N2O ligands. Appl Organomet Chem 2007. [DOI: 10.1002/aoc.1336] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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141
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Mandal S, Mukherjee R. A new tyrosinase model with 1,3-bis[(2-dimethylaminoethyl)iminomethyl]benzene: Binuclear copper(I) and phenoxo/hydroxo-bridged dicopper(II) complexes. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2006.04.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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142
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Wang X, Ding J, Vittal JJ. Syntheses, structures and properties of copper(II) complexes containing N-(2-hydroxybenzyl)-amino amide ligands. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2006.01.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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143
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Sreenivasulu B, Zhao F, Gao S, Vittal JJ. Synthesis, Structures and Catecholase Activity of a New Series of Dicopper(II) Complexes of Reduced Schiff Base Ligands. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600022] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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144
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Peralta RA, Neves A, Bortoluzzi AJ, Dos Anjos A, Xavier FR, Szpoganicz B, Terenzi H, de Oliveira MCB, Castellano E, Friedermann GR, Mangrich AS, Novak MA. New unsymmetric dinuclear CuIICuII complexes and their relevance to copper(II) containing metalloenzymes and DNA cleavage. J Inorg Biochem 2006; 100:992-1004. [PMID: 16563512 DOI: 10.1016/j.jinorgbio.2006.01.041] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Revised: 01/18/2006] [Accepted: 01/24/2006] [Indexed: 11/17/2022]
Abstract
The new homodinuclear complexes, [Cu(2)(II)(HLdtb)(mu-OCH(3))](ClO(4))(2) (1) and [Cu(2)(II)(Ldtb)(mu-OCH(3))](BPh(4)) (2), with the unsymmetrical N(5)O(2) donor ligand (H(2)Ldtb) - {2-[N,N-Bis(2-pyridylmethyl)aminomethyl]-6-[N',N'-(3,5-di-tert-butylbenzyl-2-hydroxy)(2-pyridylmethyl)]aminomethyl}-4-methylphenol have been synthesized and characterized in the solid state by X-ray crystallography. In both cases the structure reveals that the complexes have a common {Cu(II)(mu-phenoxo)(mu-OCH(3))Cu(II)} structural unit. Magnetic susceptibility studies of 1 and 2 reveal J values of -38.3 cm(-1) and -2.02 cm(-1), respectively, and that the degree of antiferromagnetic coupling is strongly dependent on the coordination geometries of the copper centers within the dinuclear {Cu(II)(mu-OCH(3))(mu-phenolate)Cu(II)} structural unit. Solution studies in dichloromethane, using UV-Visible spectroscopy and electrochemistry, indicate that under these experimental conditions the first coordination spheres of the Cu(II) centers are maintained as observed in the solid state structures, and that both forms can be brought into equilibrium ([Cu(2)(HLdtb)(mu-OCH(3))](2+)=[Cu(2)(Ldtb)(mu-OCH(3))](+)+H(+)) by adjusting the pH with Et(3)N (Ldtb(2-) is the deprotonated form of the ligand). On the other hand, potentiometric titration studies of 1 in an ethanol/water mixture (70:30 V/V; I=0.1M KCl) show three titrable protons, indicating the dissociation of the bridging CH(3)O(-) group.The catecholase activity of 1 and 2 in methanol/water buffer (30:1 V/V) demonstrates that the deprotonated form is the active species in the oxidation of 3,5-di-tert-butylcatechol and that the reaction follows Michaelis-Menten behavior with k(cat)=5.33 x 10(-3)s(-1) and K(M)=3.96 x 10(-3)M. Interestingly, 2 can be electrochemically oxidized with E(1/2)=0.27 V vs.Fc(+)/Fc (Fc(+)/Fc is the redox pair ferrocinium/ferrocene), a redox potential which is believed to be related to the formation of a phenoxyl radical. Since these complexes are redox active species, we analyzed their activity toward the nucleic acid DNA, a macromolecule prone to oxidative damage. Interestingly these complexes promoted DNA cleavage following an oxygen dependent pathway.
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Affiliation(s)
- Rosely A Peralta
- Departamento de Química - LABINC - Universidade Federal de Santa Catarina, Campus Universitário - Trindade, 88040-900 Florianópolis, SC, Brazil
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145
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Catalytic oxidation of 3,5-di-tert-butylcatechol by a manganese(III) 18-azametallacrown-6 compound: Synthesis, crystal structure, fluorescence, magnetic and kinetic investigation. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2006.01.045] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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146
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Anekwe J, Hammerschmidt A, Rompel A, Krebs B. Altering the Activity of Catechol Oxidase Model Compounds by Electronic Influence on the Copper Core. Z Anorg Allg Chem 2006. [DOI: 10.1002/zaac.200600046] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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147
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Mukherjee J, Mukherjee R. Reaction with dioxygen of a Cu(I) complex of 1-benzyl-[3-(2'-pyridyl)]pyrazole triggers ethyl acetate hydrolysis: acetato-/pyrazolato-, dihydroxo- and diacetato-bridged Cu(II) complexes. Dalton Trans 2006:1611-21. [PMID: 16547535 DOI: 10.1039/b512086a] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A copper(I) compound [(L2)Cu(MeCN)2][ClO4] (1) containing a new bidentate N-donor ligand L2, 1-benzyl-[3-(2'-pyridyl)]pyrazole, derived from the condensation of HL1 [HL1 = 3-(2-pyridyl)pyrazole] and benzyl chloride, has been synthesized. Structural analysis reveals that in the copper(I) centre is coordinated by a pyridine and a pyrazole nitrogen from L2 and two MeCN molecules, providing a distorted tetrahedral geometry. Reaction of with dioxygen in N,N'-dimethylformamide (dmf) at 25 degrees C and subsequent workup with MeCO2Et afforded an acetato-/pyrazolato-bridged polymeric copper(II) compound [(mu-L1)Cu(mu-O2CMe)]n (2). Notably, the deprotonated form of HL(1) and MeCO2- have originated from debenzylation of L2 and hydrolysis of MeCO2Et, respectively. The structural analysis of reveals a near-planar {Cu2(mu-L1)2}2+ core unit in which two adjacent Cu(II) ions are bridged by the deprotonated N,N-bidentate pyridylpyrazole units of two L1 and each such {Cu2(mu-L1)2}2+ unit is bridged by MeCO2- in a monodentate bridging mode [Cu...Cu separations (A): 3.9232(4) pyrazolate bridge; 3.3418(4) acetate bridge], providing a polymeric network. Careful oxygenation of in MeCN led to the isolation of a dihydroxo-bridged dicopper(II) compound [{(L2)Cu(mu-OH)(OClO3)}2] (3). Interestingly, complex brings about hydrolysis of MeCO2Et under mild conditions (dmf, ca. 60 degrees C), generating a bis-mu-1,3-acetato-bridged dicopper(II) complex, [{(L2)Cu(dmf)(mu-O2CMe)}2][ClO4]2.dmf.0.5MeCO2H (4). Compounds and have {Cu2(mu-OH)2}2+ [Cu...Cu separation of 2.8474(9) A] and {Cu2(mu-O2CMe)2}2+ cores [Cu...Cu separation: 3.0988(26) and 3.0792(29) A (two independent molecules in the asymmetric unit)] in which each Cu(II) centre is terminally coordinated by L2. A rationale has been provided for the observed debenzylation of L2 and hydrolysis of MeCO(2)Et. The intramolecular magnetic coupling between the Cu(II) (S = 1/2) ions was found to be ferromagnetic (2J = 82 cm(-1)) in the case of , but antiferromagnetic for (2J = -158 cm(-1)) and (2J = -96 cm(-1)). Absorption and EPR spectroscopic properties of the copper(II) compounds have also been investigated.
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Affiliation(s)
- Jhumpa Mukherjee
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
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148
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Izzet G, Akdas H, Hucher N, Giorgi M, Prangé T, Reinaud O. Supramolecular Assemblies with Calix[6]arenes and Copper Ions: from Dinuclear to Trinuclear Linear Arrangements of Hydroxo−Cu(II) Complexes. Inorg Chem 2006; 45:1069-77. [PMID: 16441115 DOI: 10.1021/ic051221e] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Complexation of copper(II) by calix[6]arene-based ligands bearing either two or three N-benzylimidazole coordinating arms under basic conditions has been studied. Whereas the tris(imidazole) derivative stabilizes dicationic 5-coordinate aqua complexes in a mononuclear state with an intracavity bound guest, in the presence of hydroxide ions, the latter undergo dimerization. An X-ray structure revealed decoordination of one imidazole arm and formation of a bis(hydroxo) bridged Cu(II) core with a square-planar geometry for both metal centers sandwiched by two empty calixarene cavities. Upon methanolysis, the dinuclear complex underwent an unexpected rearrangement leading to the clean formation of a trinuclear complex. X-ray diffraction analyses of this novel species revealed a trinuclear core constructed around a central Cu(II) ion that is doubly bridged through either methoxide or hydroxide anions to two Cu(II) ions hold by two calixarene units. The same complex could be directly synthesized by reacting the ligand with copper(II) perchlorate in a 2:3 ratio in the presence of base. In solution, the tetrahydroxo Cu(3) complex was characterized by UV-vis and (1)H NMR spectroscopies and displayed an electron paramagnetic resonance (EPR) signal only below 100 K that accounts for a S = 1/2 fundamental state. Formation of the same di- and trinuclear species was observed with a calix[6]arene-based bis(imidazole) ligand, which demonstrates the generality of the reaction schemes. All these results emphasize the versatility of the calix[6]arene scaffold for the stabilization of metal complexes with various nuclearities.
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Affiliation(s)
- Guillaume Izzet
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR CNRS 8601, 45 rue des Saints-Pères, Université René Descartes (Paris V), 75270 Paris Cedex 06, France
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Koval IA, Gamez P, Belle C, Selmeczi K, Reedijk J. Synthetic models of the active site of catechol oxidase: mechanistic studies. Chem Soc Rev 2006; 35:814-40. [PMID: 16936929 DOI: 10.1039/b516250p] [Citation(s) in RCA: 420] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ability of copper proteins to process dioxygen at ambient conditions has inspired numerous research groups to study their structural, spectroscopic and catalytic properties. Catechol oxidase is a type-3 copper enzyme usually encountered in plant tissues and in some insects and crustaceans. It catalyzes the conversion of a large number of catechols into the respective o-benzoquinones, which subsequently auto-polymerize, resulting in the formation of melanin, a dark pigment thought to protect a damaged tissue from pathogens. After the report of the X-ray crystal structure of catechol oxidase a few years earlier, a large number of publications devoted to the biomimetic modeling of its active site appeared in the literature. This critical review (citing 114 references) extensively discusses the synthetic models of this enzyme, with a particular emphasis on the different approaches used in the literature to study the mechanism of the catalytic oxidation of the substrate (catechol) by these compounds. These are the studies on the substrate binding to the model complexes, the structure-activity relationship, the kinetic studies of the catalytic oxidation of the substrate and finally the substrate interaction with (per)oxo-dicopper adducts. The general overview of the recognized types of copper proteins and the detailed description of the crystal structure of catechol oxidase, as well as the proposed mechanisms of the enzymatic cycle are also presented.
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Affiliation(s)
- Iryna A Koval
- Leiden Institute of Chemistry, Leiden University, P. O. Box 9502, 2300 RA Leiden, Netherlands
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Jocher C, Pape T, Seidel WW, Gamez P, Reedijk J, Hahn FE. Catechol Oxidation with Dinuclear Copper Complexes of Aliphatic Tripodal Amino Alcohols. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200500554] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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