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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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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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Miller KR, Paretsky JD, Follmer AH, Heinisch T, Mittra K, Gul S, Kim IS, Fuller FD, Batyuk A, Sutherlin KD, Brewster AS, Bhowmick A, Sauter NK, Kern J, Yano J, Green MT, Ward TR, Borovik AS. Artificial Iron Proteins: Modeling the Active Sites in Non-Heme Dioxygenases. Inorg Chem 2020; 59:6000-6009. [PMID: 32309932 PMCID: PMC7219546 DOI: 10.1021/acs.inorgchem.9b03791] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An important class of non-heme dioxygenases contains a conserved Fe binding site that consists of a 2-His-1-carboxylate facial triad. Results from structural biology show that, in the resting state, these proteins are six-coordinate with aqua ligands occupying the remaining three coordination sites. We have utilized biotin-streptavidin (Sav) technology to design new artificial Fe proteins (ArMs) that have many of the same structural features found within active sites of these non-heme dioxygenases. An Sav variant was isolated that contains the S112E mutation, which installed a carboxylate side chain in the appropriate position to bind to a synthetic FeII complex confined within Sav. Structural studies using X-ray diffraction (XRD) methods revealed a facial triad binding site that is composed of two N donors from the biotinylated ligand and the monodentate coordination of the carboxylate from S112E. Two aqua ligands complete the primary coordination sphere of the FeII center with both involved in hydrogen bond networks within Sav. The corresponding FeIII protein was also prepared and structurally characterized to show a six-coordinate complex with two exogenous acetato ligands. The FeIII protein was further shown to bind an exogenous azido ligand through replacement of one acetato ligand. Spectroscopic studies of the ArMs in solution support the results found by XRD.
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Affiliation(s)
- Kelsey R. Miller
- Department of Chemistry, 1102 Natural Science II, University of California, Irvine, CA 9269
| | - Jonathan D. Paretsky
- Department of Chemistry, 1102 Natural Science II, University of California, Irvine, CA 9269
| | - Alec H. Follmer
- Department of Chemistry, 1102 Natural Science II, University of California, Irvine, CA 9269
| | - Tillmann Heinisch
- Department of Chemistry, University of Basel, PO Box 3350, Mattenstrasse 24a, BPR 1096, CH-4002 Basel, Switzerland
| | - Kaustuv Mittra
- Department of Molecular Biosciences and Biochemistry, University of California, Irvine, CA 92697
| | - Sheraz Gul
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - In-Sik Kim
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Franklin D. Fuller
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025 USA
| | - Alexander Batyuk
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025 USA
| | - Kyle D. Sutherlin
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Aaron S. Brewster
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Asmit Bhowmick
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Nicholas K. Sauter
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Jan Kern
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Junko Yano
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Michael T. Green
- Department of Chemistry, 1102 Natural Science II, University of California, Irvine, CA 9269
- Department of Molecular Biosciences and Biochemistry, University of California, Irvine, CA 92697
| | - Thomas R. Ward
- Department of Chemistry, University of Basel, PO Box 3350, Mattenstrasse 24a, BPR 1096, CH-4002 Basel, Switzerland
| | - A. S. Borovik
- Department of Chemistry, 1102 Natural Science II, University of California, Irvine, CA 9269
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Indira S, Vinoth G, Bharathi M, Bharathi S, Kalilur Rahiman A, Shanmuga Bharathi K. Catechol oxidase and phenoxazinone synthase mimicking activities of mononuclear Fe(III) and Co(III) complexes of amino-bis(phenolate)-based mixed ligands: Synthesis, spectral and electrochemical studies. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.118988] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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5
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Ségaud N, Drienovská I, Chen J, Browne WR, Roelfes G. Artificial Metalloproteins for Binding and Stabilization of a Semiquinone Radical. Inorg Chem 2018; 56:13293-13299. [PMID: 29027794 PMCID: PMC5676253 DOI: 10.1021/acs.inorgchem.7b02073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
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The interaction of a number of first-row
transition-metal ions with a 2,2′-bipyridyl alanine (bpyA)
unit incorporated into the lactococcal multidrug resistance regulator
(LmrR) scaffold is reported. The composition of the active site is
shown to influence binding affinities. In the case of Fe(II), we demonstrate
the need of additional ligating residues, in particular those containing
carboxylate groups, in the vicinity of the binding site. Moreover,
stabilization of di-tert-butylsemiquinone radical
(DTB-SQ) in water was achieved by binding to the designed
metalloproteins, which resulted in the radical being shielded from
the aqueous environment. This allowed the first characterization of
the radical semiquinone in water by resonance Raman spectroscopy. A coordination study of first-row transition-metal ions to bipyridine
alanine (bpyA) incorporated into the lactococcal multidrug resistance
regulator (LmrR) scaffold is reported. The designed metalloproteins
were shown to bind and stabilize the di-tert-butylsemiquinone
radical (DTB-SQ) in water, allowing for the first resonance
Raman characterization of this radical species in water.
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Affiliation(s)
- Nathalie Ségaud
- Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ivana Drienovská
- Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Juan Chen
- Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Wesley R Browne
- Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Gerard Roelfes
- Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands
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Pringouri K, Anwar MU, Mansour L, Doupnik N, Beldjoudi Y, Gavey EL, Pilkington M, Rawson JM. A novel bis-1,2,4-benzothiadiazine pincer ligand: synthesis, characterization and first row transition metal complexes. Dalton Trans 2018; 47:15725-15736. [DOI: 10.1039/c8dt03346c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The synthesis and coordination chemistry of ligand LH2 to first row transition metals is described in which it acts as a tridentate N,N′,N′′-donor.
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Affiliation(s)
| | - Muhammad U. Anwar
- Natural and Medical Sciences Research Center
- University of Nizwa
- Nizwa
- Sultanate of Oman
| | - Liz Mansour
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Nathan Doupnik
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Yassine Beldjoudi
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Emma L. Gavey
- Department of Chemistry
- Brock University
- St Catharines
- Canada
| | | | - Jeremy M. Rawson
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
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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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8
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Dey D, De A, Yadav HR, Guin PS, Choudhury AR, Kole N, Biswas B. An Oxido-Bridged Diiron(II) Complex as Functional Model of Catechol Dioxygenase. ChemistrySelect 2016. [DOI: 10.1002/slct.201600575] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dhananjay Dey
- Department of Chemistry; Raghunathpur College; Purulia 723 133,West Bengal India
| | - Abhranil De
- Department of Chemistry; Raghunathpur College; Purulia 723 133,West Bengal India
| | - Hare Ram Yadav
- Department of Chemical Sciences; Indian Institute of Science Education and Research Mohali; S.A.S. Nagar, Manauli PO Mohali 140 306 India
| | | | - Angshuman Roy Choudhury
- Department of Chemical Sciences; Indian Institute of Science Education and Research Mohali; S.A.S. Nagar, Manauli PO Mohali 140 306 India
| | - Niranjan Kole
- Department of Chemistry; Raghunathpur College; Purulia 723 133,West Bengal India
| | - Bhaskar Biswas
- Department of Chemistry; Raghunathpur College; Purulia 723 133,West Bengal India
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Lakk-Bogáth D, Csonka R, Lorencz N, Giorgi M, Speier G, Kaizer J. Oxidant dependent oxidation of copper bound catecholate: Catecholase versus catechol dioxygenase activity. Polyhedron 2015. [DOI: 10.1016/j.poly.2015.09.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Shemesh Y, Yavin E. Postsynthetic conjugation of RNA to carboxylate and dicarboxylate molecules. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2015; 34:753-62. [PMID: 26422297 DOI: 10.1080/15257770.2015.1073299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Carboxylates and dicarboxylates are important phosphate mimics. Herein, we present a simple synthetic route for the preparation of RNA carboxylate/dicarboxylate conjugates, starting from suitably protected NH2- and COOH-containing molecules that are coupled to the RNA on the solid support. The key point in our method was the use of trimethylsilylethanol (TMSE-OH) protecting group, which is removed simultaneously with the silyl protecting group on the 2'-OH of the RNA ribose (e.g. t-Butyldimethylsilyl) during the final RNA cleavage/deprotection steps. The usefulness of this method was demonstrated by preparing different RNA-phosphate mimics oligos.
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Affiliation(s)
- Yossi Shemesh
- a School of Pharmacy, The Hebrew University of Jerusalem , Hadassah Ein-Kerem , Jerusalem , Israel
| | - Eylon Yavin
- a School of Pharmacy, The Hebrew University of Jerusalem , Hadassah Ein-Kerem , Jerusalem , Israel
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11
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Ghosh K, Tyagi N, Kumar Dhara A, Singh UP. Spontaneous Reduction of Mononuclear High-Spin Iron(III) Complexes to Mononuclear Low-Spin Iron(II) Complexes in Aqueous Media and Nuclease Activity via Self-Activation. Chem Asian J 2014; 10:350-61. [DOI: 10.1002/asia.201402954] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Indexed: 11/08/2022]
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12
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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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13
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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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14
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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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15
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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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16
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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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17
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18
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Ahuja G, Mathur P. Fe (III) complexes of a bis-benzimidazolyl diamide ligand: spectral and catalytic studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 83:180-186. [PMID: 21900037 DOI: 10.1016/j.saa.2011.08.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/26/2011] [Accepted: 08/10/2011] [Indexed: 05/31/2023]
Abstract
A new tetradentate bis benzimidaozlyl diamide ligand N,N'-Bis (benzimidazol-2-yl-methyl)-hexane-1,6-dicarboxamide (GBSA) has been synthesized and utilized to prepare new Fe(III) complexes with exogenous anionic ligand X=Cl(-) and NO(3)(-). Isomer shift values are in the range found for Iron in the +3 oxidation state while Quadrupole Splitting indicates large distortion from a six coordinate geometry, a finding supported by low temperature EPR work. The E(1/2) values are found to be quite cathodic indicating stability of the Iron (III) complexes. The oxidation of alcohols was investigated using [Fe(GBSA)Cl(3)] as the catalyst with TBHP as an alternate source of oxygen. The respective carbonyl products have been isolated and characterized by (1)H NMR, electronic spectroscopy, mass and IR spectral studies.
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Affiliation(s)
- Gauri Ahuja
- Department of Chemistry, University of Delhi, Delhi, India.
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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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20
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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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21
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Boča M, Jameson RF, Linert W. Fascinating variability in the chemistry and properties of 2,6-bis-(benzimidazol-2-yl)-pyridine and 2,6-bis-(benzthiazol-2-yl)-pyridine and their complexes. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2010.09.010] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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22
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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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23
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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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25
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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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26
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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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27
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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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28
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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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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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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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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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Bitterlich B, Anilkumar G, Gelalcha FG, Spilker B, Grotevendt A, Jackstell R, Tse MK, Beller M. Development of a General and Efficient Iron-Catalyzed Epoxidation with Hydrogen Peroxide as Oxidant. Chem Asian J 2007; 2:521-9. [PMID: 17441190 DOI: 10.1002/asia.200600407] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The development of inexpensive and practical iron catalysts for the environmentally benign epoxidation of olefins with hydrogen peroxide as terminal oxidant is described. By systematic variation of ligands, metal sources, and reaction conditions, it was discovered that FeCl3 x 6 H2O in combination with pyridine-2,6-dicarboxylic acid and different amines shows high reactivity and excellent selectivity towards the epoxidation of aromatic olefins and moderate reactivity towards that of aliphatic olefins.
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Affiliation(s)
- Bianca Bitterlich
- Leibniz-Institut für Katalyse, Albert-Einstein-Str. 29a, D-18059 Rostock, Germany
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