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Shapterhasmi T, Palani N, Velusamy M, Bhuvanesh NS, Sundaravel K, Easwaramoorthi S. Iron(III) Complexes of Pyrrolidine and Piperidine Appended Tridentate 3N Donor Ligands as Models for Catechol Dioxygenase Enzymes. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.120924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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2
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Misawa-Suzuki T, Ikeda R, Komatsu R, Toriba R, Miyamoto R, Nagao H. Geometry and Electronic Structures of Cobalt(II) and Iron(III) Complexes Bearing Bis(2-pyridylmethyl)ether or Alkylbis(2-pyridylmethyl)amine. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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3
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Das A, Rajeev A, Bhunia S, Arunkumar M, Chari N, Sankaralingam M. Synthesis, characterization and antimicrobial activity of nickel(II) complexes of tridentate N3 ligands. Inorganica Chim Acta 2021. [DOI: 10.1016/j.ica.2021.120515] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ajaykamal T, Sharma M, Islam NS, Palaniandavar M. Rapid atmospheric carbon dioxide fixation by nickel(II) complexes: meridionally coordinated diazepane-based 3N ligands facilitate fixation. Dalton Trans 2021; 50:8045-8056. [PMID: 34018498 DOI: 10.1039/d1dt00299f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Octahedral complexes of the type [Ni(L)(H2O)3](ClO4)2 (1 and 2), where L is the tridentate 3N ligand 4-methyl-1-(pyrid-2-ylmethyl)-1,4-diazacycloheptane (L1, 1), or 4-methyl-1-(N-methylimidazolyl)-1,4-diazacycloheptane (L2, 2), have been isolated and characterized using elemental analysis, ESI-MS and electronic absorption spectroscopy. The DFT optimized structures of 1 and 2 reveal that the tridentate 3N ligands are coordinated meridionally constituting a distorted octahedral coordination geometry around nickel(ii). In methanol solution, the complexes, upon treatment with triethylamine, generate the reactive red colored low-spin square planar Ni-OH intermediate [Ni(L1/L2)(OH)]+ (1a and 2a), as characterized by ESI-MS and electronic absorption spectroscopy, and energy minimized structures. The latter when exposed to the atmosphere rapidly absorbs atmospheric CO2 to produce the carbonate bridged dinickel(ii) complexes [Ni2(L1/L2)2(μ-CO3)(H2O)2](ClO4)2 (3 and 4), as characterized by elemental analysis and the IR spectral feature (∼1608 cm-1) characteristic of bridging carbonate. The single crystal X-ray structure of 3 reveals the presence of a dinickel(ii) core bridged by a carbonate anion in a symmetric mode. Both the Ni(ii) centers are identical to each other with each Ni(ii) possessing a distorted octahedral coordination geometry constituted by a meridionally coordinated 3N ligand, a carbonate ion and a water molecule. The decay kinetics of the red intermediates generated by 1 (kobs, 7.7 ± 0.1 × 10-5 s-1) and 2 (kobs, 5.8 ± 0.3 × 10-4 s-1) in basic methanol solution with atmospheric CO2 has been determined by absorption spectroscopy. DFT studies illustrate that meridional coordination of the 3N ligand and the electron-releasing imidazole ring as in 2 facilitate fixation of CO2. The carbonate complex 3 efficiently catalyzes the conversion of styrene oxide into cyclic carbonate by absorbing atmospheric and pure CO2 with excellent selectivity.
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Affiliation(s)
- Tamilarasan Ajaykamal
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India.
| | - Mitu Sharma
- Department of Chemical Sciences, Tezpur University, Tezpur, Assam, India
| | - Nasreen S Islam
- Department of Chemical Sciences, Tezpur University, Tezpur, Assam, India
| | - Mallayan Palaniandavar
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India.
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Biological Inspirations: Iron Complexes Mimicking the Catechol Dioxygenases. MATERIALS 2021; 14:ma14123250. [PMID: 34204660 PMCID: PMC8231159 DOI: 10.3390/ma14123250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/07/2021] [Accepted: 06/09/2021] [Indexed: 11/18/2022]
Abstract
Within the broad group of Fe non-heme oxidases, our attention was focused on the catechol 1,2- and 2,3-dioxygenases, which catalyze the oxidative cleavage of aromatic rings. A large group of Fe complexes with N/O ligands, ranging from N3 to N2O2S, was developed to mimic the activity of these enzymes. The Fe complexes discussed in this work can mimic the intradiol/extradiol catechol dioxygenase reaction mechanism. Electronic effects of the substituents in the ligand affect the Lewis acidity of the Fe center, increasing the ability to activate dioxygen and enhancing the catalytic activity of the discussed biomimetic complexes. The ligand architecture, the geometric isomers of the complexes, and the substituent steric effects significantly affect the ability to bind the substrate in a monodentate and bidentate manner. The substrate binding mode determines the preferred mechanism and, consequently, the main conversion products. The preferred mechanism of action can also be affected by the solvents and their ability to form the stable complexes with the Fe center. The electrostatic interactions of micellar media, similar to SDS, also control the intradiol/extradiol mechanisms of the catechol conversion by discussed biomimetics.
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Phenoxazinone synthase activity of two iron(III) complexes comprising the same Schiff base ligand: Biomimetic functional model and mechanistic investigation. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.01.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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7
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Stable host–guest complexes of bis-2,6-pyridinedicarboxylate iron(III) with dihydroxybenzenes. Polyhedron 2017. [DOI: 10.1016/j.poly.2017.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Balamurugan M, Vadivelu P, Palaniandavar M. Iron(iii) complexes of tripodal tetradentate 4N ligands as functional models for catechol dioxygenases: the electronic vs. steric effect on extradiol cleavage. Dalton Trans 2014; 43:14653-68. [DOI: 10.1039/c3dt52145a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Sankaralingam M, Saravanan N, Anitha N, Suresh E, Palaniandavar M. Biomimetic iron(iii) complexes of facially and meridionally coordinating tridentate 3N ligands: tuning of regioselective extradiol dioxygenase activity in organized assemblies. Dalton Trans 2014; 43:6828-41. [DOI: 10.1039/c3dt52350k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Sankaralingam M, Palaniandavar M. Diiron(III) complexes of tridentate 3N ligands as functional models for methane monooxygenases: Effect of the capping ligand on hydroxylation of alkanes. Polyhedron 2014. [DOI: 10.1016/j.poly.2013.08.067] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Saravanan N, Sankaralingam M, Palaniandavar M. Manganese(ii) complexes of tetradentate 4N ligands with diazepane backbones for catalytic olefin epoxidation: effect of nucleophilicity of peroxo complexes on reactivity. RSC Adv 2014. [DOI: 10.1039/c3ra44729d] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mononuclear Mn(ii) complexes of linear 4N ligands have been studied as catalysts for deformylation of aldehydes and epoxidation (H2O2) of unfunctionalised olefins to understand the role of ligand stereoelectronic factors.
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Heidari S, Safaei E, Wojtczak A, Cotič P, Kozakiewicz A. Iron(III) complexes of pyridine-based tetradentate aminophenol ligands as structural model complexes for the catechol-bound intermediate of catechol dioxygenases. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.02.067] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Váradi T, Pap JS, Giorgi M, Párkányi L, Csay T, Speier G, Kaizer J. Iron(III) complexes with meridional ligands as functional models of intradiol-cleaving catechol dioxygenases. Inorg Chem 2013; 52:1559-69. [PMID: 23320898 DOI: 10.1021/ic302378r] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Six dichloroiron(III) complexes of 1,3-bis(2'-arylimino)isoindoline (BAIH) with various N-donor aryl groups have been characterized by spectroscopy (infrared, UV-vis), electrochemistry (cyclic voltammetry), microanalysis, and in two cases X-ray crystallography. The structurally characterized Fe(III)Cl(2)(L(n)) complexes (n = 3, L(3) = 1,3-bis(2'-thiazolylimino)isoindoline and n = 5, L(5) = 1,3-bis(4-methyl-2'-piridylimino)isoindoline) are five-coordinate, trigonal bipyramidal with the isoindoline ligands occupying the two axial and one equatorial positions meridionally. These compounds served as precursors for catechol dioxygenase models that were formed in solution upon addition of 3,5-di-tert-butylcatechol (H(2)DBC) and excess triethylamine. These adducts react with dioxygen in N,N-dimethylformamide, and the analysis of the products by chromatography and mass spectrometry showed high intradiol over extradiol selectivity (the intradiol/extradiol product ratios varied between 46.5 and 6.5). Kinetic measurements were performed by following the change in the intensity of the catecholate to iron ligand-to-metal charge transfer (LMCT) band, the energy of which is influenced by the isoindolinate-ligand (827-960 nm). In combination with electrochemical investigations the kinetic studies revealed an inverse trend between reaction rates and oxidation potentials associated with the coordinated DBC(2-). On the basis of these results, a substrate activation mechanism is suggested for this system in which the geometry of the peroxide-bridged intermediate may be of key importance in regioselectivity.
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Affiliation(s)
- Tünde Váradi
- Department of Chemistry, University of Pannonia, 8201 Veszprém, Hungary
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Karimpour T, Safaei E, Wojtczak A, Jagličić Z, Kozakiewicz A. Iron(III) complexes of ethylenediamine derivatives of aminophenol ligands as models for enzyme–substrate adducts of catechol dioxygenases. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2012.10.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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Saberikia I, Safaei E, Kowsari MH, Lee YI, Cotic P, Bruno G, Rudbari HA. A new iron(III) complex of glycine derivative of amine-chloro substituted phenol ligand: Synthesis, characterization and catechol dioxygenase activity. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.06.047] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Saravanan N, Palaniandavar M. Manganese(II) complexes of pyridyl-appended diazacyclo-alkanes: Effect of ligand backbone ring size on catalytic olefin oxidation. Inorganica Chim Acta 2012. [DOI: 10.1016/j.ica.2012.01.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Visvaganesan K, Ramachitra S, Palaniandavar M. Functional models for enzyme–substrate adducts of catechol dioxygenase enzymes: The Lewis basicity of facially coordinating tridentate phenolate ligands tunes the rate of dioxygenation and product selectivity. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.08.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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18
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PALANIANDAVAR MALLAYAN, VISVAGANESAN KUSALENDIRAN. Mononuclear non-heme iron(III) complexes of linear and tripodal tridentate ligands as functional models for catechol dioxygenases: Effect of N-alkyl substitution on regioselectivity and reaction rate. J CHEM SCI 2011. [DOI: 10.1007/s12039-011-0110-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Anitha N, Palaniandavar M. Mononuclear iron(iii) complexes of 3N ligands in organized assemblies: spectral and redox properties and attainment of regioselective extradiol dioxygenase activity. Dalton Trans 2011; 40:1888-901. [DOI: 10.1039/c0dt01012j] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Sundaravel K, Sankaralingam M, Suresh E, Palaniandavar M. Biomimetic iron(iii) complexes of N3O and N3O2 donor ligands: protonation of coordinated ethanolate donor enhances dioxygenase activity. Dalton Trans 2011; 40:8444-58. [PMID: 21785763 DOI: 10.1039/c1dt10495k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Karuppasamy Sundaravel
- Centre for Bioinorganic Chemistry, School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, India
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Sundaravel K, Suresh E, Saminathan K, Palaniandavar M. Iron(III) complexes of N2O and N3O donor ligands as functional models for catechol dioxygenase enzymes: ether oxygen coordination tunes the regioselectivity and reactivity. Dalton Trans 2011; 40:8092-107. [DOI: 10.1039/c0dt01598a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Karuppasamy Sundaravel
- Centre for Bioinorganic Chemistry, School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, Tamilnadu, India
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Singh R, Banerjee A, Rajak KK. Iron(III) complexes using NNS reduced Schiff bases and NNOS coordinating tetradentate ligands: Synthesis, structure and catecholase activity. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2010.05.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Sundaravel K, Suresh E, Palaniandavar M. Iron(III) complexes of tridentate N3 ligands as models for catechol dioxygenases: Stereoelectronic effects of pyrazole coordination. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2010.04.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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El Azhari N, Devers-Lamrani M, Chatagnier G, Rouard N, Martin-Laurent F. Molecular analysis of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHs. JOURNAL OF HAZARDOUS MATERIALS 2010; 177:593-601. [PMID: 20096999 DOI: 10.1016/j.jhazmat.2009.12.074] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Revised: 12/15/2009] [Accepted: 12/17/2009] [Indexed: 05/28/2023]
Abstract
A PCR-based molecular tool was developed to estimate the diversity of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHS. A degenerate primer pair specific to catA sequences was designed by multiple alignment of known sequences coding a key intermediate of the beta-ketoadiapate pathway degrading catechol, namely catechol 1,2-dioxygenase. The specificity of this primer pair was assessed in 21 pure strains by PCR and sequencing. Comparison of the 16S rDNA and catA phylogenies revealed an absence of congruence between these two genes. The primer set was able to amplify catA sequences in DNA extracts from an industrial soil highly contaminated with heavy metals and polycyclic aromatic hydrocarbons (PAHs). RFLP screening of the catA library (95 clones) yielded 32 RFLP families. All of the 43 clone sequences obtained exhibited 86% identity on average to known CatA. Phylogenetic analysis revealed that these CatA sequences were related to Actinobacteria, alpha-, beta- and gamma-Proteobacteria phyla and confirmed the absence of congruence with 16S rDNA sequences, which implies horizontal gene transfer of the cat gene cluster between soil microbiota. Our results suggest that the diversity of the catA bacterial community is maintained in highly contaminated soil.
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Affiliation(s)
- Najoi El Azhari
- INRA/Université de Bourgogne, Soil and Environmental Microbiology, 17 rue sully, BP 86510, 21065 Dijon Cedex, France.
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Mayilmurugan R, Sankaralingam M, Suresh E, Palaniandavar M. Novel square pyramidal iron(iii) complexes of linear tetradentate bis(phenolate) ligands as structural and reactive models for intradiol-cleaving 3,4-PCD enzymes: Quinone formation vs. intradiol cleavage. Dalton Trans 2010; 39:9611-25. [DOI: 10.1039/c0dt00171f] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Anitha N, Palaniandavar M. Selective extradiol cleavage of catechol achieved in organized assemblies using [Fe(BPA)Cl3] (BPA = bis(pyridylmethyl)amine). Dalton Trans 2010; 39:1195-7. [DOI: 10.1039/b915059e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Dhanalakshmi T, Suresh E, Palaniandavar M. Synthesis, structure, spectra and reactivity of iron(III) complexes of imidazole and pyrazole containing ligands as functional models for catechol dioxygenases. Dalton Trans 2009:8317-28. [PMID: 19789784 DOI: 10.1039/b903602d] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of new 1 : 1 iron(iii) complexes of the type [Fe()Cl(3)], where is a tridentate 3N donor ligand, has been isolated and studied as functional models for catechol dioxygenases. The ligands (1-methyl-1H-imidazol-2-ylmethyl)pyrid-2-ylmethyl-amine (), N,N-dimethyl-N'-(1-methyl-1H-imidazol-2-ylmethyl)ethane-1,2-diamine () and N-(1-methyl-1H-imidazol-2-ylmethyl)-N'-phenylethane-1,2-diamine () are linear while the ligands tris(1-pyrazolyl)methane (), tris(3,5-dimethyl-1-pyrazolyl)methane () and tris(3-iso-propylpyrazolyl)methane () are tripodal ones. All the complexes have been characterized by spectral and electrochemical methods. The X-ray crystal structure of the dinuclear catecholate adduct [Fe()(TCC)](2)O, where TCC(2-) is a tetrachlorocatecholate dianion, has been successfully determined. In this complex both the iron(iii) atoms are bridged by a mu-oxo group and each iron(iii) center possesses a distorted octahedral coordination geometry in which the ligand is facially coordinated and the remaining coordination sites are occupied by the TCC(2-) dianion. Spectral studies suggest that addition of a base like Et(3)N induces the mononuclear complex species [Fe()(TCC)Cl] to dimerize forming a mu-oxo-bridged complex. The spectral and electrochemical properties of the catecholate adducts of the complexes generated in situ reveal that a systematic variation in the ligand donor atom type significantly influences the Lewis acidity of the iron(iii) center and hence the interaction of the complexes with simple and substituted catechols. The 3,5-di-tert-butylcatecholate (DBC(2-)) adducts of the type [Fe()(DBC)Cl], where is a linear tridentate ligand (), undergo mainly oxidative intradiol cleavage of the catechol in the presence of dioxygen. Also, the extradiol-to-intradiol product selectivity (E : I) is enhanced upon removal of the coordinated chloride ion in these adducts to obtain [Fe()(DBC)(Sol)](+) and upon incorporating coordinated N-methylimidazolyl nitrogen in them. In contrast to the iron(iii) complexes of imidazole-based ligands, those of the tripodal pyrazole-based ligands yield major amounts of the oxidized product benzoquinone and small amounts of both intra- and extradiol products. One of the pyrazole arms coordinated in the equatorial plane of these sterically constrained complexes is substituted by a solvent molecule upon adduct formation with DBC(2-), which encourages molecular oxygen to attack this site leading to benzoquinone formation. The DBSQ/DBC(2-) redox potentials of both the imidazole- and pyrazole-based complexes fall in the narrow range of -0.186 to -0.214 V supporting this proposal.
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Functional model for catecholase-like activity: Synthesis, structure, spectra, and catalytic activity of iron(III) complexes with substituted-salicylaldimine ligands. Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2009.06.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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29
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Mayilmurugan R, Visvaganesan K, Suresh E, Palaniandavar M. Iron(III) Complexes of Tripodal Monophenolate Ligands as Models for Non-Heme Catechol Dioxygenase Enzymes: Correlation of Dioxygenase Activity with Ligand Stereoelectronic Properties. Inorg Chem 2009; 48:8771-83. [DOI: 10.1021/ic900969n] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Eringathodi Suresh
- Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar − 364 002, India
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Caglio R, Valetti F, Caposio P, Gribaudo G, Pessione E, Giunta C. Fine-Tuning of Catalytic Properties of Catechol 1,2-Dioxygenase by Active Site Tailoring. Chembiochem 2009; 10:1015-24. [DOI: 10.1002/cbic.200800836] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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31
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Zhang Y, Meng XG, Liao ZR, Li DF, Liu CL. Synthesis, structures and polyphenol oxidase activities of dicopper and dicobalt complexes. J COORD CHEM 2009. [DOI: 10.1080/00958970802389755] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Yong Zhang
- a Key Laboratory of Pesticide & Chemical Biology, Ministry of Education , College of Chemistry, Central China Normal University , Wuhan 430079, P.R. China
- b School of Chemical and Materials Engineering , Huangshi Institute of Technology , Huangshi 435003, P.R. China
| | - Xiang Gao Meng
- a Key Laboratory of Pesticide & Chemical Biology, Ministry of Education , College of Chemistry, Central China Normal University , Wuhan 430079, P.R. China
| | - Zhan Ru Liao
- a Key Laboratory of Pesticide & Chemical Biology, Ministry of Education , College of Chemistry, Central China Normal University , Wuhan 430079, P.R. China
| | - Dong Feng Li
- a Key Laboratory of Pesticide & Chemical Biology, Ministry of Education , College of Chemistry, Central China Normal University , Wuhan 430079, P.R. China
| | - Chang Lin Liu
- a Key Laboratory of Pesticide & Chemical Biology, Ministry of Education , College of Chemistry, Central China Normal University , Wuhan 430079, P.R. China
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Panda MK, John A, Shaikh MM, Ghosh P. Mimicking the Intradiol Catechol Cleavage Activity of Catechol Dioxygenase by High-Spin Iron(III) Complexes of a New Class of a Facially Bound [N2O] Ligand. Inorg Chem 2008; 47:11847-56. [DOI: 10.1021/ic801576f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manas K. Panda
- Department of Chemistry and National Single Crystal X-ray Diffraction Facility, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Alex John
- Department of Chemistry and National Single Crystal X-ray Diffraction Facility, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Mobin M. Shaikh
- Department of Chemistry and National Single Crystal X-ray Diffraction Facility, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
| | - Prasenjit Ghosh
- Department of Chemistry and National Single Crystal X-ray Diffraction Facility, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
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Mayilmurugan R, Stoeckli-Evans H, Palaniandavar M. Novel Iron(III) Complexes of Sterically Hindered 4N Ligands: Regioselectivity in Biomimetic Extradiol Cleavage of Catechols. Inorg Chem 2008; 47:6645-58. [DOI: 10.1021/ic702410d] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ramasamy Mayilmurugan
- School of Chemistry, Bharathidasan University, Tiruchirapalli 620 024, India, and Department of Chemistry, University of Neuchatel, Neuchatel, Switzerland
| | - Helen Stoeckli-Evans
- School of Chemistry, Bharathidasan University, Tiruchirapalli 620 024, India, and Department of Chemistry, University of Neuchatel, Neuchatel, Switzerland
| | - Mallayan Palaniandavar
- School of Chemistry, Bharathidasan University, Tiruchirapalli 620 024, India, and Department of Chemistry, University of Neuchatel, Neuchatel, Switzerland
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Sundaravel K, Dhanalakshmi T, Suresh E, Palaniandavar M. Synthesis, structure, spectra and reactivity of iron(iii) complexes of facially coordinating and sterically hindering 3N ligands as models for catechol dioxygenases. Dalton Trans 2008:7012-25. [DOI: 10.1039/b809142k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Visvaganesan K, Mayilmurugan R, Suresh E, Palaniandavar M. Iron(III) Complexes of Tridentate 3N Ligands as Functional Models for Catechol Dioxygenases: The Role of Ligand N-alkyl Substitution and Solvent on Reaction Rate and Product Selectivity. Inorg Chem 2007; 46:10294-306. [DOI: 10.1021/ic700822y] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kusalendiran Visvaganesan
- School of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar-364 002, India
| | - Ramasamy Mayilmurugan
- School of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar-364 002, India
| | - Eringathodi Suresh
- School of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar-364 002, India
| | - Mallayan Palaniandavar
- School of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, India, Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar-364 002, India
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Bruijnincx PCA, Lutz M, Spek AL, Hagen WR, van Koten G, Gebbink RJMK. Iron(III)-catecholato complexes as structural and functional models of the intradiol-cleaving catechol dioxygenases. Inorg Chem 2007; 46:8391-402. [PMID: 17722878 DOI: 10.1021/ic700741v] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structural and spectroscopic characterization of mononuclear iron(III)-catecholato complexes of ligand L4 (methyl bis(1-methylimidazol-2-yl)(2-hydroxyphenyl)methyl ether, HL4) are described, which closely mimic the enzyme-substrate complex of the intradiol-cleaving catechol dioxygenases. The tridentate, tripodal monoanionic ligand framework of L4 incorporates one phenolato and two imidazole donor groups and thus well reproduces the His2Tyr endogenous donor set. In fact, regarding the structural features of [FeIII(L4)(tcc)(H2O)] (5.H2O, tcc = tetrachlorocatechol) in the solid state, the complex constitutes the closest structural model reported to date. The iron(III)-catecholato complexes mimic both the structural features of the active site and its spectroscopic characteristics. As part of its spectroscopic characterization, the electron paramagnetic resonance (EPR) spectra were successfully simulated using a simple model that accounts for D strain. The simulation procedure showed that the observed g = 4.3 line is an intrinsic part of the EPR envelope of the studied complexes and should not necessarily be attributed to a highly rhombic impurity. [FeIII(L4)(dtbc)(H2O)] (dtbc = 3,5-di-tert-butylcatechol) was studied with respect to its dioxygen reactivity, and oxidative cleavage of the substrate was observed. Intradiol- and extradiol-type cleavage products were found in roughly equal amounts. This shows that an accurate structural model of the first-coordination sphere of the active site is not sufficient for obtaining regioselectivity.
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Affiliation(s)
- Pieter C A Bruijnincx
- Chemical Biology & Organic Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
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Mayilmurugan R, Suresh E, Palaniandavar M. A New Tripodal Iron(III) Monophenolate Complex: Effects of Ligand Basicity, Steric Hindrance, and Solvent on Regioselective Extradiol Cleavage. Inorg Chem 2007; 46:6038-49. [PMID: 17589990 DOI: 10.1021/ic700646m] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The new iron(III) complex [Fe(L3)Cl(2)], where H(L3) is the tripodal monophenolate ligand N,N-dimethyl-N'-(pyrid-2-ylmethyl)-N'-(2-hydroxy-3,5-dimethylbenzyl)ethylenediamine, has been isolated and studied as a structural and functional model for catechol dioxygenase enzymes. The complex possesses a distorted octahedral iron(III) coordination geometry constituted by the phenolate oxygen, pyridine nitrogen and two amine nitrogens of the tetradentate ligand, and two cis-coordinated chloride ions. The Fe-O-C bond angle (134.0 degrees) and Fe-O bond length (1.889 Angstrom) are very close to those (Fe-O-C, 133 degrees and 148 degrees, Fe-O(tyrosinate), 1.81 and 1.91 Angstrom) of protocatechuate 3,4-dioxygenase enzymes. When the complex is treated with AgNO(3), the ligand-to-metal charge transfer (LMCT) band around 650 nm (epsilon, 2390 M(-1) cm(-1)) is red shifted to 665 nm with an increase in absorptivity (epsilon, 2630 M(-1) cm(-1)) and the Fe(III)/Fe(II) redox couple is shifted to a slightly more positive potential (-0.329 to -0.276 V), suggesting an increase in the Lewis acidity of the iron(III) center upon the removal of coordinated chloride ions. Furthermore, when 3,5-di-tert-butylcatechol (H(2)DBC) pretreated with 2 mol of Et(3)N is added to the complex [Fe(L3)Cl(2)] treated with 2 equiv of AgNO(3), two intense catecholate-to-iron(III) LMCT bands (719 nm, epsilon, 3150 M(-1) cm(-1); 494 nm, epsilon, 3510 M(-1) cm(-1)) are observed. Similar observations are made when H(2)DBC pretreated with 2 mol of piperidine is added to [Fe(L3)Cl(2)], suggesting the formation of [Fe(L3)(DBC)] with bidentate coordination of DBC(2-). On the other hand, when H(2)DBC pretreated with 2 mol of Et(3)N is added to [Fe(L3)Cl(2)], only one catecholate-to-iron(III) LMCT band (617 nm; epsilon, 4380 M(-1) cm(-1)) is observed, revealing the formation of [Fe(L3)(HDBC)(Cl)] involving monodentate coordination of the catecholate. The appearance of the DBSQ/H(2)DBC couple for [Fe(L3)(DBC)] at a potential (-0.083 V) more positive than that (-0.125 V) for [Fe(L3)(HDBC)(Cl)] reveals that chelated DBC(2-) in the former is stabilized toward oxidation more than the coordinated HDBC(-). It is remarkable that the complex [Fe(L3)(HDBC)(Cl)] undergoes slow selective extradiol cleavage (17.3%) of H(2)DBC in the presence of O(2), unlike the iron(III)-phenolate complexes known to yield only intradiol products. It is probable that the weakly coordinated (2.310 Angstrom) -NMe(2) group rather than chloride in the substrate-bound complex is displaced, facilitating O(2) attack on the iron(III) center and, hence, the extradiol cleavage. In contrast, when the cleavage reaction was performed in the presence of a stronger base-like piperidine before and after the removal of the coordinated chloride ions, a faster intradiol cleavage was favored over extradiol cleavage, suggesting the importance of the bidentate coordination of the catecholate substrate in facilitating intradiol cleavage. Also, intradiol cleavage is favored in dimethylformamide and acetonitrile solvents, with enhanced intradiol cleavage yields of 94 and 40%, respectively.
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Functional model for intradiol-cleaving catechol 1,2-dioxygenase: Synthesis, structure, spectra, and catalytic activity of iron(III) complexes with substituted salicylaldimine ligands. Inorganica Chim Acta 2007. [DOI: 10.1016/j.ica.2007.02.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Palaniandavar M, Mayilmurugan R. Mononuclear non-heme iron(III) complexes as functional models for catechol dioxygenases. CR CHIM 2007. [DOI: 10.1016/j.crci.2007.01.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Pelagatti P, Bacchi A, Balordi M, Caneschi A, Giannetto M, Pelizzi C, Gonsalvi L, Peruzzini M, Ugozzoli F. A Ligand-Driven Geometry Switch in Octahedral and Trigonal-Bipyramidal Iron Complexes Containing (H)PNO and PNN Ligands. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200600731] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Dhanalakshmi T, Bhuvaneshwari M, Palaniandavar M. Iron(III) complexes of certain meridionally coordinating tridentate ligands as models for non-heme iron enzymes: The role of carboxylate coordination. J Inorg Biochem 2006; 100:1527-34. [PMID: 16814389 DOI: 10.1016/j.jinorgbio.2006.05.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Revised: 04/13/2006] [Accepted: 05/10/2006] [Indexed: 11/18/2022]
Abstract
The iron(III) complexes [Fe(pda)Cl(H(2)O)(2)] (1), [Fe(tpy)Cl(3)] (2), and [Fe(bbp)Cl(3)] (3), where H(2)pda is pyridine-2,6-dicarboxylic acid, tpy is 2,2':6,2''-terpyridine and bbp is 2,6-bis(benzimidazolyl)pyridine, have been isolated and studied as functional models for the intradiol-cleaving catechol dioxygenase enzymes. Mixed ligand complexes of H(2)pda with the bidentate ligands 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen) have been also prepared and studied. All the complexes have been characterized using absorption spectral and electrochemical methods. The spectral changes in the catecholate adducts of the complexes generated in situ have been investigated. Upon interacting the complexes with catecholate anions a low energy catecholate to iron(III) charge transfer band appears, which is similar to that observed for enzyme-substrate complexes. All the complexes catalyze the oxidative intradiol cleavage of 3,5-di-tert-butylcatechol (H(2)dbc) in the presence of dioxygen. Interestingly, on replacing the pyridyl groups in 2 and the bulky benzimidazole groups in 3 by the carboxylate groups, the yields of the intradiol cleavage products of dioxygenation increases, 1 (50%)>2 (20%)>3 (10%). The higher intradiol yield for 1 has been ascribed to the meridional coordination of two carboxylate groups of pda(2-). In contrast to the trend in the intradiol cleavage yields, a tremendous decrease in the rate (200 times) is observed on replacing the two pyridyl moieties in 2 by two carboxylates as in 1 and a significant decrease in rate is observed on replacing the pyridyl moieties in 2 by strongly sigma-donating benzimidazole moieties as in 3. This is in conformity with the decrease in Lewis acidities of the iron(III) centers.
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Kurahashi T, Oda K, Sugimoto M, Ogura T, Fujii H. Trigonal-Bipyramidal Geometry Induced by an External Water Ligand in a Sterically Hindered Iron Salen Complex, Related to the Active Site of Protocatechuate 3,4-Dioxygenase. Inorg Chem 2006; 45:7709-21. [PMID: 16961363 DOI: 10.1021/ic060650p] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A unique distorted trigonal-bipyramidal geometry observed for the non-heme iron center in protocatechuate 3,4-dioxygenase (3,4-PCD) was carefully examined utilizing a sterically hindered iron salen complex, which well reproduces the endogenous His2Tyr2 donor set with water as an external ligand. X-ray crystal structures of a series of iron model complexes containing bis(3,5-dimesitylsalicylidene)-1,2-dimesitylethylenediamine indicate that a distorted trigonal-bipyramidal geometry is achieved upon binding of water as an external ligand. The extent of a structural change of the iron center from a preferred square-pyramidal to a distorted trigonal-bipyramidal geometry varies with the external ligand that is bound in the order Cl << EtO < H2O, which is consistent with the spectrochemical series. The distortion in the model system is not due to steric repulsions but electronic interactions between the external ligand and the iron center, as evidenced from the X-ray crystal structures of another series of iron model complexes with a less-hindered bis(3-xylylsalicylidene)-1,2-dimesitylethylenediamine ligand, as well as by density functional theory calculations. Further spectroscopic investigations indicate that a unique distorted trigonal-bipyramidal geometry is indeed maintained even in solution. The present model study provides a new viewpoint that a unique distorted trigonal-bipyramidal iron site might not be preorganized by a 3,4-PCD protein but could be electronically induced upon the binding of an external hydroxide ligand to the iron(III) center. The structural change induced by the external water ligand is also discussed in relation to the reaction mechanism of 3,4-PCD.
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Affiliation(s)
- Takuya Kurahashi
- Institute for Molecular Science & Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Myodaiji, Okazaki 444-8787, Japan.
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