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Mazumdar R, Saha S, Samanta B, Mondal B. Can a Nitrosyl of a Mn(II)-Porphyrin Complex Release Nitroxyl/HNO? Inorg Chem 2021; 60:18024-18030. [PMID: 34797639 DOI: 10.1021/acs.inorgchem.1c02606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In general, the nitrosyl complexes of Mn(II)-porphyrinate having the {Mn(NO)}6 configuration are not considered as HNO or nitroxyl (NO-) donors because of [MnI-NO+] nature. A nitrosyl complex of Mn(II)-porphyrin, [Mn(TMPP2-)(NO)], 1 [TMPPH2 = 5,10,15,20-tetrakis-4-methoxyphenylporphyrin], is shown to release HNO in the presence of HBF4. It is evidenced from the characteristic reaction of HNO with triphenylphosphine and isolation of the [(TMPP2-)MnIII(H2O)2](BF4), 2. This is attributed to the fact that H+ from HBF4 polarizes the NO group whereas the BF4- interacts with metal ion to stabilize the Mn(III) form. These two effects cooperatively result in the release of HNO from complex 1. In addition, complex 1 behaves as a nitroxyl (NO-) donor in the presence of [Fe(dtc)3] (dtc = diethyldithiocarbamate anion) and [Fe(TPP)(Cl)] (TPP = 5,10,15,20-tetraphenylporphyrinate) to result in [Fe(dtc)2(NO)] and [Fe(TPP)(NO)], respectively.
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Affiliation(s)
- Rakesh Mazumdar
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Shankhadeep Saha
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Bapan Samanta
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
| | - Biplab Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam 781039, India
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2
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Radoń M. Role of Spin States in Nitric Oxide Binding to Cobalt(II) and Manganese(II) Porphyrins. Is Tighter Binding Always Stronger? Inorg Chem 2015; 54:5634-45. [PMID: 26000802 DOI: 10.1021/ic503109a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Binding of nitric oxide (NO) to metalloporphyrins and heme groups is important in biochemistry while challenging to describe accurately by density functional theory (DFT) calculations. Here, the structural and thermochemical aspect of NO binding to Co(II) and Mn(II) porphyrins is investigated by DFT and DFT-D (dispersion-corrected) calculations, supported by reliable coupled-cluster methodology (CCSD(T)), and critically correlated with the experimental data. It is argued that whereas the bonding of NO to Co(II) porphyrin is a simple radical recombination, the bonding of NO to Mn(II) porphyrin is accompanied by a crossing of spin states. For this reason, the spin-state conversion energy contributes to the Mn-NO bond energy, and the paradigmatic correlation between bond length and bond energy is violated for the considered nitrosyl complexes: the Mn-NO bond is (structurally) shorter by ∼0.2 Å, albeit (energetically) weaker by a few kcal/mol, compared with the Co-NO bond. Moreover, none of the many tested DFT methods can reproduce the Co-NO and Mn-NO bond energies simultaneously, except for calculations with B3LYP*-D3, TPSSh-D3, and M06-D3 methods supplemented with the proposed spin-state energy correction (to compensate for an error on the calculated spin-state conversion energy). The results of this study are important to appreciate the role of spin-state changes in ligand binding properties of heme-related models. They also highlight the need for accurate calculations for correct interpretation of experimental data, including the qualitative structure-energy relationship.
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Affiliation(s)
- Mariusz Radoń
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland
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Kalmár J, Biri B, Lente G, Bányai I, Budimir A, Biruš M, Batinić-Haberle I, Fábián I. Detailed mechanism of the autoxidation of N-hydroxyurea catalyzed by a superoxide dismutase mimic Mn(III) porphyrin: formation of the nitrosylated Mn(II) porphyrin as an intermediate. Dalton Trans 2012; 41:11875-84. [PMID: 22911446 DOI: 10.1039/c2dt31200j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The in vitro autoxidation of N-hydroxyurea (HU) is catalyzed by Mn(III)TTEG-2-PyP(5+), a synthetic water soluble Mn(III) porphyrin which is also a potent mimic of the enzyme superoxide dismutase. The detailed mechanism of the reaction is deduced from kinetic studies under basic conditions mostly based on data measured at pH = 11.7 but also including some pH-dependent observations in the pH range 9-13. The major intermediates were identified by UV-vis spectroscopy and electrospray ionization mass spectrometry. The reaction starts with a fast axial coordination of HU to the metal center of Mn(III)TTEG-2-PyP(5+), which is followed by a ligand-to-metal electron transfer to get Mn(II)TTEG-2-PyP(4+) and the free radical derived from HU (HU˙). Nitric oxide (NO) and nitroxyl (HNO) are minor intermediates. The major pathway for the formation of the most significant intermediate, the {MnNO} complex of Mn(II)TTEG-2-PyP(4+), is the reaction of Mn(II)TTEG-2-PyP(4+) with NO. We have confirmed that the autoxidation of the intermediates opens alternative reaction channels, and the process finally yields NO(2)(-) and the initial Mn(III)TTEG-2-PyP(5+). The photochemical release of NO from the {MnNO} intermediate was also studied. Kinetic simulations were performed to validate the deduced rate constants. The investigated reaction has medical implications: the accelerated production of NO and HNO from HU may be utilized for therapeutic purposes.
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Affiliation(s)
- József Kalmár
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary H-4010, POB-21
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Electronic structure and spectra of nitrosyl complexes with cobalt and manganese porphyrins. Struct Chem 2012. [DOI: 10.1007/s11224-012-0053-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Kurtikyan TS, Hayrapetyan VA, Martirosyan GG, Ghazaryan RK, Iretskii AV, Zhao H, Pierloot K, Ford PC. Nitrosyl isomerism in amorphous Mn(TPP)(NO) solids. Chem Commun (Camb) 2012; 48:12088-90. [DOI: 10.1039/c2cc37337h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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7
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Chmura A, Szaciłowski K, Stasicka Z. The role of photoinduced electron transfer processes in photodegradation of the [Fe4(μ3-S)3(NO)7]− cluster. Nitric Oxide 2006; 15:370-9. [PMID: 16675275 DOI: 10.1016/j.niox.2006.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 03/07/2006] [Accepted: 03/19/2006] [Indexed: 10/24/2022]
Abstract
Spectroscopic and electrochemical study of the [Fe(4)(mu(3)-S)(3)(NO)(7)](-) photochemical reaction and thermodynamic calculations of relevant systems demonstrate the redox character of this process. The photoinduced electron transfer between substrate clusters in excited and ground state (probably via exciplex formation) results in dismutation yielding unstable [Fe(4)(mu(3)-S)(3)(NO)(7)](2-) and [Fe(4)(mu(3)-S)(3)(NO)(7)](0). Back electron transfer between the primary products is responsible for fast reversibility of the photochemical reaction in deoxygenated solutions. In the presence of an electron acceptor (such as O(2), MV(2+) or NO) an oxidative quenching of the (*)[Fe(4)(mu(3)-S)(3)(NO)(7)](-) is anticipated, although NO seems to participate as well in the reductive quenching. The electron acceptors can also regenerate the substrate from its reduced form ([Fe(4)(mu(3)-S)(3)(NO)(7)](2-)), whereas the other primary product ([Fe(4)(mu(3)-S)(3)(NO)(7)](0)) decomposes to the final products. The suggested mechanism fits well to all experimental observations and shows the thermodynamically favored pathways and explains formation of all major (Fe(2+), S(2-), NO) and minor products (N(2)O, Fe(3+)). The photodissociation of nitrosyl ligands suggested earlier as the primary photochemical step cannot be, however, definitely excluded and may constitute a parallel pathway of [Fe(4)(mu(3)-S)(3)(NO)(7)](-) photolysis.
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Affiliation(s)
- Antonina Chmura
- Jagiellonian University, Faculty of Chemistry, Ingardena 3, 30-060 Kraków, Poland
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Martirosyan GG, Azizyan AS, Kurtikyan TS, Ford PC. In Situ FT-IR and UV−vis Spectroscopy of the Low-Temperature NO Disproportionation Mediated by Solid State Manganese(II) Porphyrinates. Inorg Chem 2006; 45:4079-87. [PMID: 16676969 DOI: 10.1021/ic051824q] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The heterogeneous reaction between NO gas and sublimed layers of manganese(II) porphyrinato complexes Mn(Por) (Por = TPP (tetraphenylporphyrinato dianion), TMP (tetramesitylporphyrinato dianion), or TPP(d20) (perdeuterated tetraphenylporphyrinato dianion)) has been monitored by IR and optical spectroscopy over the temperature range of 77 K to room temperature. These manganese porphyrins promote NO disproportionation to NO2 species and N2O, and the reaction proceeds via several distinct stages. At 90 K, the principal species observed spectrally are the nitric oxide dimer, cis-ONNO, two manganese nitrosyls, the simple NO adduct Mn(Por)(NO), and another intermediate (1) that is apparently critical to the disproportionation mechanism. This key intermediate is formed prior to N2O evolution, and proposals regarding its likely structure are offered. When the system is warmed to 130 K, the disproportionation products, N2O and the O-coordinated nitrito complex Mn(Por)(NO)(ONO) (2), are formed. IR spectral changes show that, upon further warming to 200 K, 2 isomerizes into the N-bonded nitro linkage isomer Mn(Por)(NO)(NO2) (3). After it is warmed to room temperature, the latter species loses NO and converts to the known 5-coordinate nitrito complex Mn(Por)(ONO) (4).
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Affiliation(s)
- Garik G Martirosyan
- Armenian Research Institute of Applied Chemistry (ARIAC), 375005, Yerevan, Armenia
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Praneeth VKK, Näther C, Peters G, Lehnert N. Spectroscopic Properties and Electronic Structure of Five- and Six-Coordinate Iron(II) Porphyrin NO Complexes: Effect of the Axial N-Donor Ligand. Inorg Chem 2006; 45:2795-811. [PMID: 16562937 DOI: 10.1021/ic050865j] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this paper, the differences in the spectroscopic properties and electronic structures of five- and six-coordinate iron(II) porphyrin NO complexes are explored using [Fe(TPP)(NO)] (1; TPP = tetraphenylporphyrin) and [Fe(TPP)(MI)(NO)] (2; MI = 1-methylimidazole) type systems. Binding of N-donor ligands in axial position trans to NO to five-coordinate complexes of type 1 is investigated using UV-vis absorption and 1H NMR spectroscopies. This way, the corresponding binding constants Keq are determined and the 1H NMR spectra of 1 and 2 are assigned for the first time. In addition, 1H NMR allows for the determination of the degree of denitrosylation in solutions of 1 with excess base. The influence of the axial ligand on the properties of the coordinated NO is then investigated. Vibrational spectra (IR and Raman) of 1 and 2 are presented and assigned using isotope substitution and normal-coordinate analysis. Obtained force constants are 12.53 (N-O) and 2.98 mdyn/A (Fe-NO) for 1 compared to 11.55 (N-O) and 2.55 mdyn/A (Fe-NO) for 2. Together with the NMR results, this provides experimental evidence that binding of the trans ligand weakens the Fe-NO bond. The principal bonding schemes of 1 and 2 are very similar. In both cases, the Fe-N-O subunit is strongly bent. Donation from the singly occupied pi* orbital of NO into d(z2) of iron(II) leads to the formation of an Fe-NO sigma bond. In addition, a medium-strong pi back-bond is present in these complexes. The most important difference in the electronic structures of 1 and 2 occurs for the Fe-NO sigma bond, which is distinctively stronger for 1 in agreement with the experimental force constants. The increased sigma donation from NO in 1 also leads to a significant transfer of spin density from NO to iron, as has been shown by magnetic circular dichroism (MCD) spectroscopy in a preceding Communication (Praneeth, V. K. K.; Neese, F.; Lehnert, N. Inorg. Chem. 2005, 44, 2570-2572). This is confirmed by the 1H NMR results presented here. Hence, further experimental and computational evidence is provided that complex 1 has noticeable Fe(I)NO+ character relative to 2, which is an Fe(II)NO(radical) complex. Finally, using MCD theory and quantum chemical calculations, the absorption and MCD C-term spectra of 1 and 2 are assigned for the first time.
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Affiliation(s)
- V K K Praneeth
- Institut für Anorganische Chemie, Christian-Albrechts-Universität Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany
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Sauaia MG, de Lima RG, Tedesco AC, da Silva RS. Nitric Oxide Production by Visible Light Irradiation of Aqueous Solution of Nitrosyl Ruthenium Complexes. Inorg Chem 2005; 44:9946-51. [PMID: 16363866 DOI: 10.1021/ic051346j] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[Ru(II)L(NH(3))(4)(pz)Ru(II)(bpy)(2)(NO)](PF(6))(5) (L is NH(3), py, or 4-acpy) was prepared with good yields in a straightforward way by mixing an equimolar ratio of cis-[Ru(NO(2))(bpy)(2)(NO)](PF(6))(2), sodium azide (NaN(3)), and trans-[RuL(NH(3))(4)(pz)] (PF(6))(2) in acetone. These binuclear compounds display nu(NO) at ca. 1945 cm(-)(1), indicating that the nitrosyl group exhibits a sufficiently high degree of nitrosonium ion (NO(+)). The electronic spectrum of the [Ru(II)L(NH(3))(4)(pz)Ru(II)(bpy)(2)(NO)](5+) complex in aqueous solution displays the bands in the ultraviolet and visible regions typical of intraligand and metal-to-ligand charge transfers, respectively. Cyclic voltammograms of the binuclear complexes in acetonitrile give evidence of three one-electron redox processes consisting of one oxidation due to the Ru(2+/3+) redox couple and two reductions concerning the nitrosyl ligand. Flash photolysis of the [Ru(II)L(NH(3))(4)(pz)Ru(II)(bpy)(2)(NO)](5+) complex is capable of releasing nitric oxide (NO) upon irradiation at 355 and 532 nm. NO production was detected and quantified by an amperometric technique with a selective electrode (NOmeter). The irradiation at 532 nm leads to NO release as a consequence of a photoinduced electron transfer. All species exhibit similar photochemical behavior, a feature that makes their study extremely important for their future application in the upgrade of photodynamic therapy in living organisms.
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Affiliation(s)
- Marília Gama Sauaia
- Departamento de Química da Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. dos Bandeirantes 3900, 14040-901, Ribeirão Preto, São Paulo, Brazil
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11
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Cabail MZ, Lace PJ, Uselding J, Pacheco A. Kinetic studies of the photoinitiated NO-releasing reactions of N,N′-bis-(carboxymethyl)-N,N′-dinitroso-1,4-phenylenediamine. J Photochem Photobiol A Chem 2002. [DOI: 10.1016/s1010-6030(02)00231-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Coppens P, Novozhilova I, Kovalevsky A. Photoinduced linkage isomers of transition-metal nitrosyl compounds and related complexes. Chem Rev 2002; 102:861-84. [PMID: 11942781 DOI: 10.1021/cr000031c] [Citation(s) in RCA: 358] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Philip Coppens
- Department of Chemistry, State University of New York at Buffalo, Buffalo, NY 14260-3000, USA.
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Laverman LE, Wanat A, Oszajca J, Stochel G, Ford PC, van Eldik R. Mechanistic studies on the reversible binding of nitric oxide to metmyoglobin. J Am Chem Soc 2001; 123:285-93. [PMID: 11456515 DOI: 10.1021/ja001696z] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The ferriheme protein metmyoglobin (metMb) in buffer solution at physiological pH 7.4 reversibly binds the biomessenger molecule nitric oxide to yield the nitrosyl adduct (metMb(NO)). The kinetics of the association and dissociation processes were investigated by both laser flash photolysis and stopped-flow kinetics techniques at ambient and high pressure, in three laboratories using several different sources of metMb. The activation parameters DeltaH, DeltaS, and DeltaV were calculated from the kinetic effects of varying temperature and hydrostatic pressure. For the "on" reaction of metMb plus NO, reasonable agreement was found between the various techniques with DeltaH(on), DeltaS(on), and DeltaV(on) determined to have the respective values approximately 65 kJ mol(-1), approximately 60 J mol(-1) K(-1), and approximately 20 cm(3) mol(-1). The large and positive DeltaS and DeltaV values are consistent with the operation of a limiting dissociative ligand substitution mechanism whereby dissociation of the H(2)O occupying the sixth distal coordination site of metMb must precede formation of the Fe-NO bond. While the activation enthalpies of the "off" reaction displayed reasonable agreement between the various techniques (ranging from 68 to 83 kJ mol(-1)), poorer agreement was found for the DeltaS(off) values. For this reason, the kinetics for the "off" reaction were determined more directly via NO trapping experiments, which gave the respective activation parameters DeltaH(off) = 76 kJ mol(-1), DeltaS(off) = approximately 41 J mol(-1) K(-1), and DeltaV(off) = 20 cm(3) mol(-1)), again consistent with a limiting dissociative mechanism. These results are discussed in reference to other investigations of the reactions of NO with both model systems and metalloproteins.
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Affiliation(s)
- L E Laverman
- Contribution from the Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA
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Jene PG, Ibers JA. Syntheses and structural characterization of the (OCnOPor) capped porphyrins: Co(OC2OPor).CH2Cl2, Co(OC2OPor)(NO)out.0.46CHCl3, Co(OC3OPor).CHCl3, and Co(OC3OPor)(MeIm).3C7H8. Inorg Chem 2000; 39:5796-802. [PMID: 11151382 DOI: 10.1021/ic0006753] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The compounds Co(OC2OPor).CH2Cl2 (1), Co(OC2OPor)(NO)out.0.46CHCl3 (2), Co(OC3OPor).CHCl3 (3), and Co(OC3OPor)(MeIm).3C7H8 (4) (OC2OPor = 5,10,15,20-(benzene-1,2,4,5- tetrakis(2-phenyloxy)ethoxy)-2',2",2"',2""-tetraylporphyrinato dianion; OC3OPor = 5,10,15,20-(benzene-1,2,4,5-tetrakis(2- phenyloxy)propoxy)-2',2",2"',2""-tetraylporphyrinato dianion; MeIm = 1-methylimidazole), have been synthesized, and their structures have been determined by single-crystal X-ray diffraction methods at T = -120 degrees C: 1, a = 8.824(1) A, b = 16.674(1) A, c = 16.836(1) A, alpha = 104.453(1) degrees, beta = 92.752(1) degrees, gamma = 90.983(1) degrees, P1, Z = 2; 2, a = 9.019(1) A, b = 16.588(2) A, c = 16.909(2) A, alpha = 103.923(2) degrees, beta = 92.082(2) degrees, gamma = 93.583(2) degrees, P1, Z = 2; 3, a = 13.484(3) A, b = 14.404(3) A, c = 14.570(3) A, alpha = 105.508(3) degrees, beta = 100.678(3) degrees, gamma = 93.509(4) degrees, P1, Z = 2; 4, a = 16.490(1) A, b = 22.324(2) A, c = 17.257(1) A, b = 92.437(1) degrees, P2(1)/n, Z = 4. These compounds are the first structurally characterized Co-bound members of the OCnOPor ligand system. The NO ligand in 2 and the MeIm ligand in 4 bind asymmetrically and lead to several metrical changes in these porphyrins, e.g., variations in average porphyrin deviations and Co atom displacements relative to the porphyrinato N atoms and the mean porphyrin planes.
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Affiliation(s)
- P G Jene
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA
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Spasojevic I, Batinic-Haberle I, Fridovich I. Nitrosylation of manganese(II) tetrakis(N-ethylpyridinium-2-yl)porphyrin: a simple and sensitive spectrophotometric assay for nitric oxide. Nitric Oxide 2000; 4:526-33. [PMID: 11020341 DOI: 10.1006/niox.2000.0303] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Reaction between NO(*) and manganese tetrakis(N-ethylpyridinium-2-yl)porphyrin (Mn(III)TE-2-PyP(5+)) was investigated at 25 degrees C. At high excess of NO(*) (1.5 mM) the reaction with the oxidized, air-stable form Mn(III)TE-2-PyP(5+) (5 microM), proceeds very slowly (t(1/2) congruent with 60 min). The presence of excess ascorbate (1 mM) produces the reduced form, Mn(II)TE-2-PyP(4+), which reacts with NO(*) stoichiometrically and in the time of mixing (k congruent with 1 x 10(6) M(-1) s(-1)). The high rate of formation and the stability of the product, Mn(II)TE-2-PyP(NO)(4+) (¿Mn(NO)¿(6)), make the reaction outcompete the reaction of NO(*) with O(2). Our in vitro measurements show a linear absorbance response upon addition of NO to a PBS, pH 7.4, solution containing an excess of ascorbate over Mn(III)TE-2-PyP(5+). Thus, the observed interactions can be the basis of a convenient and sensitive spectrophotometric assay for NO(*). Also, it may have important implications for the in vivo behavior of Mn(III)TE-2-PyP(5+) which is currently exploited as a possible therapeutic agent for various oxygen-radical related disorders.
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Affiliation(s)
- I Spasojevic
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
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Cheng L, Novozhilova I, Kim C, Kovalevsky A, Bagley KA, Coppens P, Richter-Addo GB. First Observation of Photoinduced Nitrosyl Linkage Isomers of Iron Nitrosyl Porphyrins. J Am Chem Soc 2000. [DOI: 10.1021/ja001243u] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lin Cheng
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
| | - Irina Novozhilova
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
| | - Chris Kim
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
| | - Andrey Kovalevsky
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
| | - Kimberly A. Bagley
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
| | - Philip Coppens
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
| | - George B. Richter-Addo
- Department of Chemistry State University of New York at Buffalo Buffalo, New York 14260-3000 Department of Chemistry State University College of New York at Buffalo Buffalo, New York, 14222 Department of Chemistry and Biochemistry University of Oklahoma, 620 Parrington Oval Norman, Oklahoma, 73019
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De Leo M, Ford PC. Reversible Photolabilization of NO from Chromium(III)-Coordinated Nitrite. A New Strategy for Nitric Oxide Delivery. J Am Chem Soc 1999. [DOI: 10.1021/ja983875a] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Malcolm De Leo
- Department of Chemistry, University of California Santa Barbara, California 93106
| | - Peter C. Ford
- Department of Chemistry, University of California Santa Barbara, California 93106
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