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Homo-Tris-Nitrones Derived from α-Phenyl- N-tert-butylnitrone: Synthesis, Neuroprotection and Antioxidant Properties. Int J Mol Sci 2020; 21:ijms21217949. [PMID: 33114714 PMCID: PMC7663103 DOI: 10.3390/ijms21217949] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 12/11/2022] Open
Abstract
Herein we report the synthesis, antioxidant and neuroprotective power of homo-tris-nitrones (HTN) 1-3, designed on the hypothesis that the incorporation of a third nitrone motif into our previously identified homo-bis-nitrone 6 (HBN6) would result in an improved and stronger neuroprotection. The neuroprotection of HTNs 1-3, measured against oligomycin A/rotenone, showed that HTN2 was the best neuroprotective agent at a lower dose (EC50 = 51.63 ± 4.32 μM), being similar in EC50 and maximal activity to α-phenyl-N-tert-butylnitrone (PBN) and less potent than any of HBNs 4-6. The results of neuroprotection in an in vitro oxygen glucose deprivation model showed that HTN2 was the most powerful (EC50 = 87.57 ± 3.87 μM), at lower dose, but 50-fold higher than its analogous HBN5, and ≈1.7-fold less potent than PBN. HTN3 had a very good antinecrotic (IC50 = 3.47 ± 0.57 μM), antiapoptotic, and antioxidant (EC50 = 6.77 ± 1.35 μM) profile, very similar to that of its analogous HBN6. In spite of these results, and still being attractive neuroprotective agents, HTNs 2 and 3 do not have better neuroprotective properties than HBN6, but clearly exceed that of PBN.
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Abstract
The recent advances of tetramethylpyrazine nitrones and quinolylnitrones for the treatment of stroke have been reviewed and compared with other agents, showing promising therapeutic applications. As a result of a functional transformation of natural product ligustrazine, (Z)-N-tert-butyl-1-(3,5,6-trimethylpyrazin-2-yl)methanimine oxide (6) is a multitarget small nitrone showing potent thrombolytic activity and free radicals scavenging power, in addition to nontoxicity and blood-brain barrier permeability. Similarly, antioxidant (Z)-N-tert-butyl-1-(2-chloro-6-methoxyquinolin-3-yl)methanimine oxide (17) is a novel agent for cerebral ischemia therapy as it is able to scavenge different types of free radical species, showing strong neuroprotection and reduced infarct size.
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Affiliation(s)
- José Marco-Contelles
- Laboratory of Medicinal Chemistry, Institute of Organic Chemistry, CSIC; Juan de la Cierva, 3, 28006 Madrid, Spain
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3
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Deletraz A, Zéamari K, Hua K, Combes M, Villamena FA, Tuccio B, Callizot N, Durand G. Substituted α-Phenyl and α-Naphthlyl- N- tert-butyl Nitrones: Synthesis, Spin-Trapping, and Neuroprotection Evaluation. J Org Chem 2020; 85:6073-6085. [PMID: 32267700 DOI: 10.1021/acs.joc.0c00563] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
New derivatives of α-phenyl-N-tert-butyl nitrone (PBN) bearing a hydroxyl, an acetate, or an acetamide substituent on the N-tert-butyl moiety and para-substituted phenyl or naphthlyl moieties were synthesized. Their ability to trap hydroxymethyl radical was evaluated by electron paramagnetic resonance spectroscopy. The presence of two electron-withdrawing substituents on both sides of the nitronyl function improves the spin-trapping properties, with 4-HOOC-PBN-CH2OAc and 4-HOOC-PBN-CH2NHAc being ∼4× more reactive than PBN. The electrochemical properties of the derivatives were further investigated by cyclic voltammetry and showed that the redox potentials of the nitrones are largely influenced by the nature of the substituents both on the aromatic ring and on the N-tert-butyl function. The acetamide derivatives PBN-CH2NHAc, 4-AcNHCH2-PBN-CH2NHAc, and 4-MeO-PBN-CH2NHAc were the easiest to oxidize. A computational approach was used to rationalize the effect of functionalization on the free energies of nitrone reactivity with hydroxymethyl radical as well as on the electron affinity and ionization potential. Finally, the neuroprotection of the derivatives was evaluated in an in vitro model of cellular injury on cortical neurons. Five derivatives showed good protection at very low concentrations (0.1-10 μM), with PBN-CH2NHAc and 4-HOOC-PBN being the two most promising agents.
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Affiliation(s)
- Anaïs Deletraz
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM & Avignon Université, Equipe Chimie Bioorganique et Systèmes Amphiphiles, 301 rue Baruch de Spinoza, BP 21239, Avignon 84916 Cedex 9, France
| | - Kamal Zéamari
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM & Avignon Université, Equipe Chimie Bioorganique et Systèmes Amphiphiles, 301 rue Baruch de Spinoza, BP 21239, Avignon 84916 Cedex 9, France
| | - Kangyu Hua
- The Ohio State University, Department of Biological Chemistry and Pharmacology, 473 West 12th Avenue, Columbus, Ohio 43210, United States
| | - Maud Combes
- Neuro-Sys, 410 Chemin Départemental 60, 13120 Gardanne, France
| | - Frederick A Villamena
- The Ohio State University, Department of Biological Chemistry and Pharmacology, 473 West 12th Avenue, Columbus, Ohio 43210, United States
| | - Béatrice Tuccio
- Aix-Marseille Université, CNRS, ICR UMR 7273, Avenue Escadrille Normandie Niemen, 13397 Marseille Cedex 20, France
| | - Noelle Callizot
- Neuro-Sys, 410 Chemin Départemental 60, 13120 Gardanne, France
| | - Grégory Durand
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS-Université Montpellier-ENSCM & Avignon Université, Equipe Chimie Bioorganique et Systèmes Amphiphiles, 301 rue Baruch de Spinoza, BP 21239, Avignon 84916 Cedex 9, France
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Deletraz A, Zéamari K, Di Meo F, Fabre PL, Reybier K, Trouillas P, Tuccio B, Durand G. Reactivities of MeO-substituted PBN-type nitrones. NEW J CHEM 2019. [DOI: 10.1039/c9nj03805a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
MeO-derivatives of phenyl nitrones were synthesized and their electrochemical and spin-trapping properties were studied.
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Affiliation(s)
- Anaïs Deletraz
- Institut des Biomolécules Max Mousseron
- UMR 5247 CNRS-Université Montpellier-ENSCM & Avignon Université
- Equipe Chimie Bioorganique et Systèmes Amphiphiles
- Avignon 84916 Cedex 9
- France
| | - Kamal Zéamari
- Institut des Biomolécules Max Mousseron
- UMR 5247 CNRS-Université Montpellier-ENSCM & Avignon Université
- Equipe Chimie Bioorganique et Systèmes Amphiphiles
- Avignon 84916 Cedex 9
- France
| | - Florent Di Meo
- INSERM U1248 IPPRITT
- Université de Limoges
- Faculté de Médecine et Pharmacie
- France
| | | | | | - Patrick Trouillas
- INSERM U1248 IPPRITT
- Université de Limoges
- Faculté de Médecine et Pharmacie
- France
- Regional Centre of Advanced Technologies and Materials
| | - Béatrice Tuccio
- Aix-Marseille Université
- CNRS
- ICR UMR 7273
- 13397 Marseille Cedex 20
- France
| | - Grégory Durand
- Institut des Biomolécules Max Mousseron
- UMR 5247 CNRS-Université Montpellier-ENSCM & Avignon Université
- Equipe Chimie Bioorganique et Systèmes Amphiphiles
- Avignon 84916 Cedex 9
- France
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5
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Gruber N, Orelli LR, Cipolletti R, Stipa P. Amidinoquinoxaline N-oxides: spin trapping of O- and C-centered radicals. Org Biomol Chem 2017; 15:7685-7695. [PMID: 28872168 DOI: 10.1039/c7ob01387f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Amidinoquinoxaline N-oxides represent a novel family of heterocyclic spin traps. In this work, their ability to trap O- and C-centered radicals was tested using selected derivatives with different structural modifications. All the studied nitrones were able to trap radicals forming persistent spin adducts, also in the case of OH and OOH radicals which are of wide biological interest as examples of ROS. The stability of the adducts was mainly attributed to the wide delocalization of the unpaired electron over the whole quinoxaline moiety. The nitroxide spectral parameters (hfccs and g-factors) were analyzed and the results were supported by DFT calculations. The N-19 hfccs and g-factors were characteristic of each aminoxyl and could aid in the identification of the trapped radical. The enhanced stability of the OH adducts under the employed reaction conditions could be ascribed to their possible stabilization by IHBs with two different acceptors: the N-O˙ moiety or the amidine functionality. DFT calculations indicate that the preferred IHB is strongly conditioned by the amidine ring size. While five membered homologues show a clear preference for the IHB with the N-O˙ group, in six membered derivatives this stabilizing interaction is preferentially established with the amidine nitrogen as an IHB acceptor.
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Affiliation(s)
- Nadia Gruber
- SIMAU Dept. - Chemistry Division, Università Politecnica delle Marche, Via Brecce Bianche 12, Ancona (I-60131), Italy.
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Gruber N, Piehl LL, Rubin de Celis E, Díaz JE, García MB, Stipa P, Orelli LR. Amidinoquinoxaline N-oxides as novel spin traps. RSC Adv 2015. [DOI: 10.1039/c4ra14335c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
A series of nitrones were synthesized and tested as novel spin traps. The adducts generated by CH3 addition showed remarkably persistent signals. Their EPR features and kinetics were rationalised by DFT and MP2 calculations.
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Affiliation(s)
- Nadia Gruber
- Departamento de Química Orgánica
- Facultad de Farmacia y Bioquímica
- Universidad de Buenos Aires
- CONICET
- Buenos Aires
| | - Lidia L. Piehl
- Cátedra de Física
- Departamento de Fisicomatemática
- Facultad de Farmacia y Bioquímica
- Universidad de Buenos Aires
- Buenos Aires
| | - Emilio Rubin de Celis
- Cátedra de Física
- Departamento de Fisicomatemática
- Facultad de Farmacia y Bioquímica
- Universidad de Buenos Aires
- Buenos Aires
| | - Jimena E. Díaz
- Departamento de Química Orgánica
- Facultad de Farmacia y Bioquímica
- Universidad de Buenos Aires
- CONICET
- Buenos Aires
| | - María B. García
- Departamento de Química Orgánica
- Facultad de Farmacia y Bioquímica
- Universidad de Buenos Aires
- CONICET
- Buenos Aires
| | - Pierluigi Stipa
- S.I.M.A.U. Department Chemistry Division
- Università Politecnica delle Marche
- I-60131 Ancona
- Italy
| | - Liliana R. Orelli
- Departamento de Química Orgánica
- Facultad de Farmacia y Bioquímica
- Universidad de Buenos Aires
- CONICET
- Buenos Aires
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Rosselin M, Choteau F, Zéamari K, Nash KM, Das A, Lauricella R, Lojou E, Tuccio B, Villamena FA, Durand G. Reactivities of substituted α-phenyl-N-tert-butyl nitrones. J Org Chem 2014; 79:6615-26. [PMID: 24968285 PMCID: PMC4216227 DOI: 10.1021/jo501121g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
![]()
In
this work, a series of α-phenyl-N-tert-butyl nitrones bearing one, two, or three substituents
on the tert-butyl group was synthesized. Cyclic voltammetry
(CV) was used to investigate their electrochemical properties and
showed a more pronounced substituent effect for oxidation than for
reduction. Rate constants of superoxide radical (O2•–) reactions with nitrones were determined using
a UV–vis stopped-flow method, and phenyl radical (Ph•) trapping rate constants were measured by EPR spectroscopy. The
effect of N-tert-butyl substitution
on the charge density and electron density localization of the nitronyl
carbon as well as on the free energies of nitrone reactivity with
O2•– and HO2• were computationally rationalized at the PCM/B3LYP/6-31+G**//B3LYP/6-31G*
level of theory. Theoretical and experimental data showed that the
rates of the reaction correlate with the nitronyl carbon charge density,
suggesting a nucleophilic nature of O2•– and Ph• addition to the nitronyl carbon atom.
Finally, the substituent effect was investigated in cell cultures
exposed to hydrogen peroxide and a correlation between the cell viability
and the oxidation potential of the nitrones was observed. Through
a combination of computational methodologies and experimental methods,
new insights into the reactivity of free radicals with nitrone derivatives
have been proposed.
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Affiliation(s)
- Marie Rosselin
- Avignon Université , Equipe Chimie Bioorganique et Systèmes Amphiphiles, 33 rue Louis Pasteur, F-84000 Avignon, France
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Bao X, Tao P, Villamena FA, Hadad CM. Spin trapping of hydroperoxyl radical by a cyclic nitrone conjugated to β-cyclodextrin: a computational study. Theor Chem Acc 2012; 131. [PMID: 23585725 DOI: 10.1007/s00214-012-1248-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Spin trapping of hydroperoxyl radical (HOO.) by the amide-linked conjugate of 5-carbamoyl-5-methyl-1-pyrroline N-oxide (AMPO) to β-cyclodextrin (β-CD) was studied computationally using a two-layered ONIOM method. From a conformational perspective, the "internal" conformation of 5R-β-CD-AMPO is more favored than the "external" conformation in which the nitrone is located outside of the cavity of the β-CD. When the HOO. addition product is formed, the most stable isomer has the nitroxyl (N1-O1) moiety pointing inside the cavity of the β-CD. Thus, this "internal" conformation might protect the N1-O1 moiety of the resulting spin adduct from access by reducing agents, thereby improving the lifetime of the radical adduct. The computed energetic barrier for HOO. addition to the 5R-β-CD-AMPO is 8.7 kcal/mol, which is marginally smaller than spin trapping by the non-conjugated AMPO (that is, without the β-CD). To optimize the reactivity of the β-CD-AMPO conjugate, the effect of a spacer unit between the AMPO segment and the β-CD moiety with varying methylene units, (CH2) n (n = 1, 2, 3), on the energetics of HOO. addition was evaluated. The structure with only one methylene spacer (n = 1) appears to be optimal as determined by the smaller activation barrier (6.2 kcal/mol) for HOO. addition to the nitrone moiety. Compared with very time-consuming quantum mechanical methods, the ONIOM method appears to offer significant advantages for evaluation of the best β-CD-AMPO conjugate for trapping of such reactive oxygen species and providing for the rational design of novel nitrones as spin traps.
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Affiliation(s)
- Xiaoguang Bao
- Department of Chemistry, Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
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9
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Liu Y, Song Y, Du L, Villamena FA, Ji Y, Tian Q, Liu KJ, Liu Y. Novel glutathione-linked nitrones as dual free radical probes. NEW J CHEM 2011. [DOI: 10.1039/c1nj20033j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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10
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Durand G, Choteau F, Pucci B, Villamena FA. Reactivity of superoxide radical anion and hydroperoxyl radical with alpha-phenyl-N-tert-butylnitrone (PBN) derivatives. J Phys Chem A 2009; 112:12498-509. [PMID: 18998656 DOI: 10.1021/jp804929d] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nitrones have exhibited pharmacological activity against radical-mediated pathophysiological conditions and as analytical reagents for the identification of transient radical species by electron paramagnetic resonance (EPR) spectroscopy. In this work, competitive spin trapping, stopped-flow kinetics, and density functional theory (DFT) were employed to assess and predict the reactivity of O(2)(*-) and HO(2)(*) with various para-substituted alpha-phenyl-N-tert-butylnitrone (PBN) spin traps. Rate constants of O(2)(*-) trapping by nitrones were determined using competitive UV-vis stopped-flow method with phenol red (PR) as probe, while HO(2)(*) trapping rate constants were calculated using competition kinetics with 5,5-dimethylpyrroline N-oxide (DMPO) by employing EPR spectroscopy. The effects of the para substitution on the charge density of the nitronyl-carbon and on the free energies of nitrone reactivity with O(2)(*-) and HO(2)(*) were computationally rationalized at the PCM/B3LYP/6-31+G(d,p)//B3LYP/6-31G(d) level of theory. Theoretical and experimental data show that the rate of O(2)(*-) addition to PBN derivatives is not affected by the polar effect of the substituents. However, the reactivity of HO(2)(*) follows the Hammett equation and is increased as the substituent becomes more electron withdrawing. This supports the conclusion that the nature of HO(2)(*) addition to PBN derivatives is electrophilic, while the addition of O(2)(*-) to PBN-type compounds is only weakly electrophilic.
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Affiliation(s)
- Grégory Durand
- Laboratoire de Chimie Bioorganique et des Systèmes Moléculaires Vectoriels, Université d'Avignon et des Pays de Vaucluse, Faculté des Sciences, 33 rue Louis Pasteur, 84000 Avignon, France.
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JI YQ, WANG ZY, WANG LF, LIU KJ, LIU Y. Prediction and Evaluation of the Piperonylidene Analogue of PBN by DFT Calculations & NBT Reduction Mediated Spectral Assay. CHINESE J CHEM 2008. [DOI: 10.1002/cjoc.200890321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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Sciannamea V, Jérôme R, Detrembleur C. In-situ nitroxide-mediated radical polymerization (NMP) processes: their understanding and optimization. Chem Rev 2008; 108:1104-26. [PMID: 18254646 DOI: 10.1021/cr0680540] [Citation(s) in RCA: 352] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valérie Sciannamea
- Center for Education and Research on Macromolecules, University of Liège, Sart-Tilman, B6, 4000 Liège, Belgium
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Astolfi P, Marini M, Stipa P. Radical Trapping Properties of 3-Aryl-2H-benzo[1,4]oxazin-4-oxides. J Org Chem 2007; 72:8677-82. [PMID: 17944517 DOI: 10.1021/jo071212i] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Paola Astolfi
- Dipartimento di Scienze e Tecnologie Chimiche, Università Politecnica delle Marche, via Brecce Bianche, I-60131 Ancona, Italy
| | - Milvia Marini
- Dipartimento di Scienze e Tecnologie Chimiche, Università Politecnica delle Marche, via Brecce Bianche, I-60131 Ancona, Italy
| | - Pierluigi Stipa
- Dipartimento di Scienze e Tecnologie Chimiche, Università Politecnica delle Marche, via Brecce Bianche, I-60131 Ancona, Italy
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Liu YP, Wang LF, Nie Z, Ji YQ, Liu Y, Liu KJ, Tian Q. Effect of the Phosphoryl Substituent in the Linear Nitrone on the Spin Trapping of Superoxide Radical and the Stability of the Superoxide Adduct: Combined Experimental and Theoretical Studies. J Org Chem 2006; 71:7753-62. [PMID: 16995683 DOI: 10.1021/jo061204m] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new phosphorylated linear nitrone N-(4-hydroxybenzyliene)-1-diethoxyphosphoryl-1-methylethylamine N-oxide (4-HOPPN) was synthesized, and its X-ray structure was determined. The spin trapping ability of various kinds of free radicals by 4-HOPPN was evaluated. Kinetic study of decay of the superoxide spin adduct (4-HOPPN-OOH) shows the half-life time of 8.8 min. On the basis of the X-ray structural coordinates, theoretical analyses using density functional theory (DFT) calculations at the B3LYP/6-31+G(d,p)//B3LYP/6-31G(d) level were performed on spin-trapping reactions of superoxide radical with 4-HOPPN and PBN and three possible decay routes for their corresponding superoxide adducts. The comparative calculations on the spin-trapping reactions with superoxide radical predicted that both spin traps share an identical reaction type and have comparable potency when spin trapping superoxide radical. Analysis of the optimized geometries of 4-HOPPN-OOH and PBN-OOH reveals that an introduction of the phosphoryl group can efficiently stabilize the spin adduct through the intramolecular H-bonds, the intramolecular nonbonding attractive interactions, as well as the bulky steric protection. Examination of the decomposition thermodynamics of 4-HOPPN-OOH and PBN-OOH further supports the stabilizing role of the phosphoryl group to a linear phosphorylated spin adduct.
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Affiliation(s)
- Yang-Ping Liu
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China
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Allouch A, Roubaud V, Lauricella R, Bouteiller JC, Tuccio B. Spin trapping of superoxide by diester-nitrones. Org Biomol Chem 2005; 3:2458-62. [PMID: 15976863 DOI: 10.1039/b502836a] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The nitrone N-[(1-oxidopyridin-1-ium-4-yl)-methylidene]-1,1-bis(ethoxycarbonyl)ethylamine N-oxide (DEEPyON) was synthesized and used as a spin trapping agent. The kinetic aspects of the superoxide detection by this new spin trap and by two other diester-nitrones, i.e. 2,2-diethoxycarbonyl-3,4-dihydro-2H-pyrrole-1-oxide (DEPO) and N-benzylidene-1,1-bis(ethoxycarbonyl)ethylamine N-oxide (DEEPN), were examined by determining the rate constants for the trapping reaction and for the spin adduct decay at pH 7.2. Comparing the results obtained to those given by analogous monoester-nitrones showed that both the spin trapping and the adduct decay reactions were faster in the presence of a second ester group in the cyclic nitrone series, while the superoxide trapping capacities of linear diester-nitrones were found to be dramatically weak. It follows from this study that DEPO and 2-ethoxycarbonyl-2-methyl-3,4-dihydro-2H-pyrrole-1-oxide (EMPO) are superior when it comes to superoxide detection. Below 0.005 mol dm(-3), DEPO is to date the only nitrone capable of clearly detecting superoxide, while EMPO should be preferred at higher spin trap concentration.
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Affiliation(s)
- Ahmad Allouch
- Laboratoire TRACES, case 541, Universités d'Aix-Marseille 1 et 3, Faculté de St. Jérôme, 13397 Marseille cedex 20, France.
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16
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Tuccio B, Zeghdaoui A, Finet JP, Cerri V, Tordo P. Use of new β-phosphorylated nitrones for the spin trapping of free radicals. RESEARCH ON CHEMICAL INTERMEDIATES 1996. [DOI: 10.1163/156856796x00089] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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