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Kabanda MM, Bahadur I, Singh P. Antioxidant and anticancer properties of plant‐based bioactive flavonoids cardamonin and alpinetin: A theoretical insight from
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OOH antiradical and Cu (II) chelation mechanisms. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Mwadham M. Kabanda
- Department of Chemistry, School of Natural and Mathematical Sciences, Faculty of Science, Engineering and Agriculture University of Venda Thohoyandou South Africa
| | - Indra Bahadur
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, North‐West University South Africa
| | - Prashant Singh
- Department of Chemistry, Atma Ram Sanatan Dharma College University of Delhi New Delhi India
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2
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Barzaga R, Lestón-Sánchez L, Aguilar-Galindo F, Estévez-Hernández O, Díaz-Tendero S. Synergy Effects in Heavy Metal Ion Chelation with Aryl- and Aroyl-Substituted Thiourea Derivatives. Inorg Chem 2021; 60:11984-12000. [PMID: 34308640 DOI: 10.1021/acs.inorgchem.1c01068] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Detection and removal of metal ion contaminants have attracted great interest due to the health risks that they represent for humans and wildlife. Among the proposed compounds developed for these purposes, thiourea derivatives have been shown as quite efficient chelating agents of metal cations and have been proposed for heavy metal ion removal and for components of high-selectivity sensors. Understanding the nature of metal-ionophore activity for these compounds is thus of high relevance. We present a theoretical study on the interaction between substituted thioureas and metal cations, namely, Cd2+, Hg2+, and Pb2+. Two substituent groups have been chosen: 2-furoyl and m-trifluoromethylphenyl. Combining density functional theory simulations with wave function analysis techniques, we study the nature of the metal-thiourea interaction and characterize the bonding properties. Here, it is shown how the N,N'-disubstituted derivative has a strong affinity for Hg2+, through cation-hydrogen interactions, due to its greater oxidizing capacity.
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Affiliation(s)
- Ransel Barzaga
- Instituto de Ciencia y Tecnología de Materiales, Universidad de La Habana, 10400 La Habana, Cuba.,Departmento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Lucia Lestón-Sánchez
- Departmento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Fernando Aguilar-Galindo
- Departmento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain.,Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, Donostia-San Sebastián, E-20018, Spain
| | | | - Sergio Díaz-Tendero
- Departmento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain.,Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.,Institute for Advanced Research in Chemical Science (IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, Spain
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3
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Madala NE, Kabanda MM. LC-MS based validation and DFT investigation on the antioxidant properties of clovamide: •OH and •OOH scavenging and Cu(II) chelation mechanisms. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.130349] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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4
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Kabanda MM, Gbashi S, Madala NE. Proportional coexistence of okanin chalcone glycoside and okanin flavanone glycoside in Bidens pilosa leaves and theoretical investigation on the antioxidant properties of their aglycones. Free Radic Res 2020; 55:53-70. [PMID: 33267705 DOI: 10.1080/10715762.2020.1859107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Bidens pilosa plant has been shown to produce okanin flavanone glycoside and its chalcone derivative. In most other plants, due to chalcone isomerase enzyme, the flavanone tends to exist in higher proportions than their chalcone precursors. Herein we have utilized liquid chromatography-mass spectrometry approach and shown that within the leaves of Bidens pilosa plant the two okanin glycosides exist in unusual equal proportional distribution, which indicates that Bidens pilosa plant is an alternative rich source of these highly sought-after antioxidant molecules. The aglycone okanin chalcone (ONC) and okanin flavanone (ONF) have experimentally been shown to exhibit antioxidant activity. However, experimental findings have not conclusively determined which of the two compounds is a more potent antiradical than the other. Herein, the density functional theory (DFT) method is utilized to establish, from structural and thermodynamic energetic considerations, the preferred antioxidant molecule between the two aglycone okanins. A theoretical study on the antioxidant properties of ONC and ONF has been performed by considering their radical scavenging and metal cation (Mn+, where M = Cu(II) or Fe (III)) chelation ability. The study has been performed using B3LYP/6-31 + G(d,p) method. In the case of the metal chelation mechanism, the LANL2DZ pseudo-potential was selected to describe the selected Mn+ cations. The results of the study suggest that ONC is a better radical scavenger than ONF because of the extended electron delocalization on its neutral radical, which is due to the presence of conjugation within the ONC neutral radical after hydrogen atom abstraction. In the metal chelation mechanism, it is noted that the binding energies depend on the media, the nature of the ligand and the cation and the cation coordination site on the ligand. The charge and the spin density on Mn+ decrease on coordination to the ligand. The ability of the ligands to reduce Mn+ cations, coupled with the strong Mn+ binding properties, has significant implication on the antioxidant ability of both okanins. However, since ONC⋅⋅⋅M+n interaction results in higher binding energy than ONF⋅⋅⋅M+n interaction, the implication is that ONC is a preferred free metal ion chelator than ONF.
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Affiliation(s)
- Mwadham M Kabanda
- Department of Chemistry, University of Venda, Thohoyandou, South Africa
| | - Sefater Gbashi
- Department of Biotechnology and Food Technology, University of Johannesburg, Auckland Park, South Africa
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6
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Corinti D, Crestoni ME, Chiavarino B, Fornarini S, Scuderi D, Salpin JY. Insights into Cisplatin Binding to Uracil and Thiouracils from IRMPD Spectroscopy and Tandem Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:946-960. [PMID: 32233383 PMCID: PMC7997577 DOI: 10.1021/jasms.0c00006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The monofunctional primary complexes cis-[PtCl(NH3)2(L)]+, formed by the reaction of cisplatin, a major chemotherapeutic agent, with four nucleobases L, i.e., uracil (U), 2-thiouracil (2SU), 4-thiouracil (4SU), and 2,4-dithiouracil (24dSU), have been studied by a combination of infrared multiple photon dissociation (IRMPD) action spectroscopy in both the fingerprint (900-1900 cm-1) and the N-H/O-H stretching (3000-3800 cm-1) ranges, energy-resolved collision-induced dissociation (CID) mass spectrometry, and density functional calculations at the B3LYP/LACVP/6-311G** level. On the basis of the comparison across the experimental features and the linear IR spectra of conceivable structures, the cisplatin residue is found to promote a monodentate interaction preferentially with the O4(S4) atoms of the canonical forms of U, 4SU, and 24dSU and to the S2 atom of 2SU, yielding the most stable structures. Additional absorptions reveal the presence of minor, alternative tautomers in the sampled ion populations of 2SU and 24dSU, underlying the ability of cisplatin to increase the prospect of (therapeutically beneficial) nucleic acid strand disorder. Implication of these evidence may provide insights into drug mechanism and design.
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Affiliation(s)
- Davide Corinti
- Dipartimento
di Chimica e Tecnologie del Farmaco, Università
di Roma “La Sapienza”, P. le A. Moro 5, Roma 00185, Italy
| | - Maria Elisa Crestoni
- Dipartimento
di Chimica e Tecnologie del Farmaco, Università
di Roma “La Sapienza”, P. le A. Moro 5, Roma 00185, Italy
| | - Barbara Chiavarino
- Dipartimento
di Chimica e Tecnologie del Farmaco, Università
di Roma “La Sapienza”, P. le A. Moro 5, Roma 00185, Italy
| | - Simonetta Fornarini
- Dipartimento
di Chimica e Tecnologie del Farmaco, Università
di Roma “La Sapienza”, P. le A. Moro 5, Roma 00185, Italy
| | - Debora Scuderi
- Universite′
Paris-Saclay, CNRS, Institut de Chimie Physique
UMR8000, Orsay 91405, France
| | - Jean-Yves Salpin
- Université
Paris-Saclay, CNRS, Univ Evry,
LAMBE, Evry-Courcouronnes 91025, France
- CY
Cergy Paris Université, LAMBE, Evry-Courcouronnes 91025, France
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7
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Arslancan S, Herrera B, Lamsabhi AM. On the nature of the interaction of copper hydride and halide with substituted ethylene and acetylene. J Mol Model 2020; 26:61. [PMID: 32088811 DOI: 10.1007/s00894-020-4320-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 02/03/2020] [Indexed: 11/26/2022]
Abstract
The association of Cu-X (X = -H, -Cl, and -F) with H2CCHCHmYn and HCCCHmYn (Y = -Cl, -F, -OH, -CH3) has been studied at a high level of theory. The density functional theory (DFT) at B3LYP/6-311G(d,p)//B3LYP/6-311 + G(3df,2p) level has been chosen to calculate the structure and the relative stability of 24 different complexes. The interaction of Cu-F with the derivatives of ethylene and acetylene was found very strong, with interaction energies close to those of conventional covalent bonds. In all complexes, the most stable structure was found when Cu-X is positioned on the unsaturated CC bond, forming a three-membered ring that leads to longer CC bond distances. Both ethylene and acetylene complexes show similar trends of interaction energies with respect to the same moiety. All electronic indexes analyzed by means of the QTAIM, ELF, and NBO formalisms indicate that the strength of the interaction should increase with the number of withdrawing substituents in both series of compounds. Graphical abstractThe p-Interaction of ethylene and acetylene derivative with fluoride copper. The ELF graphs and its 2D projection show the disynaptic basins of the electrostatic binding.
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Affiliation(s)
- Serra Arslancan
- Departamento de Química, C-9, Universidad Autónoma de Madrid. Campus de Excelencia UAM-CSIC Cantoblanco, 28049, Madrid, Spain
| | - Barbara Herrera
- QTC, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul, Santiago, Chile
| | - Al Mokhtar Lamsabhi
- Departamento de Química, C-9, Universidad Autónoma de Madrid. Campus de Excelencia UAM-CSIC Cantoblanco, 28049, Madrid, Spain.
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049, Madrid, Spain.
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8
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Safi ZS, Al Hasanat SJ, Wazzan NA. DFT investigation of the amino/imino proton transfer process of 2-amino-2-oxazolin-4-one in gas phase and solution. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2018. [DOI: 10.1142/s0219633618500049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Density functional theory (DFT) at the B3LYP-6-311[Formula: see text]G(3df,2p)//6-311[Formula: see text]G(d,p) level of theory in the gas phase and solution was performed to investigate the relative stabilities of all possible tautomers of 2-amino-2-oxazolin-4-one. Five different paths have been proposed to investigate the amino/oxo [Formula: see text] imino/oxo proton transfer (PT) process. These paths are direct, mono-, di- and tri-water-assisted and self-assistance (dimerization) PT process. A clear catalytic effect has been observed when the introduction of water molecules and self-dimerization are taken place. Furthermore, barrier energies, equilibrium constants and reaction rate constants of the PT process between amine/oxo and imine/oxo tautomers of the self-assistance and in the presence of one, two and three water-assisted molecules were calculated. The computed activation barriers in the presence of water molecules are about 35–45 kcal/mol lower than those in the isolated case. In addition, the effective rate of the T1 [Formula: see text] T2 processes were also recorded, compared and discussed. Finally, time-dependent–DFT (TD–DFT) was performed to determine the electronic absorption spectra of all species under probe. A reasonable agreement with the available experiments was also achieved.
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Affiliation(s)
- Zaki S. Safi
- Department of Chemistry, Faculty of Science, Al Azhar University-Gaza, Gaza City, P. O. Box 1277, Palestine
| | - Subhia J. Al Hasanat
- Department of Chemistry, Faculty of Science, Al Azhar University-Gaza, Gaza City, P. O. Box 1277, Palestine
| | - Nuha A. Wazzan
- Department of Chemistry, Faculty of Science, King Abdulaziz University, P. O. Box 42805, Jeddah 21589, Saudi Arabia
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9
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Salpin JY, Latrous L, Haldys V, Lamsabhi AM. Interactions of Dimethyltin(IV) with Uracil As Studied in the Gas Phase. J Phys Chem A 2018; 122:992-1003. [DOI: 10.1021/acs.jpca.7b11510] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jean-Yves Salpin
- LAMBE, CNRS, Univ Evry, CEA, Université Paris-Saclay, F-91025 Evry, France
- LAMBE,
UCP, Université Paris-Seine, F-91025 Evry, France
| | - Latifa Latrous
- Faculté
des Sciences de Tunis, Laboratoire de Chimie Analytique et Electrochimie
Campus universitaire, Université de Tunis El Manar, 2092 Tunis, Tunisia
| | - Violette Haldys
- LAMBE, CNRS, Univ Evry, CEA, Université Paris-Saclay, F-91025 Evry, France
- LAMBE,
UCP, Université Paris-Seine, F-91025 Evry, France
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10
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Akinyemi TE, Wu RR, Nei YW, Cunningham NA, Roy HA, Steill JD, Berden G, Oomens J, Rodgers MT. Influence of Transition Metal Cationization versus Sodium Cationization and Protonation on the Gas-Phase Tautomeric Conformations and Stability of Uracil: Application to [Ura+Cu] + and [Ura+Ag]<sup/>. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:2438-2453. [PMID: 28895083 DOI: 10.1007/s13361-017-1771-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 07/22/2017] [Accepted: 07/22/2017] [Indexed: 05/17/2023]
Abstract
The gas-phase conformations of transition metal cation-uracil complexes, [Ura+Cu]+ and [Ura+Ag]+, were examined via infrared multiple photon dissociation (IRMPD) action spectroscopy and theoretical calculations. IRMPD action spectra were measured over the IR fingerprint and hydrogen-stretching regions. Structures and linear IR spectra of the stable tautomeric conformations of these complexes were initially determined at the B3LYP/6-31G(d) level. The four most stable structures computed were also examined at the B3LYP/def2-TZVPPD level to improve the accuracy of the predicted IR spectra. Two very favorable modes of binding are found for [Ura+Cu]+ and [Ura+Ag]+ that involve O2N3 bidentate binding to the 2-keto-4-hydroxy minor tautomer and O4 monodentate binding to the canonical 2,4-diketo tautomer of Ura. Comparisons between the measured IRMPD and calculated IR spectra enable elucidation of the conformers present in the experiments. These comparisons indicate that both favorable binding modes are represented in the experimental tautomeric conformations of [Ura+Cu]+ and [Ura+Ag]+. B3LYP suggests that Cu+ exhibits a slight preference for O4 binding, whereas Ag+ exhibits a slight preference for O2N3 binding. In contrast, MP2 suggests that both Cu+ and Ag+ exhibit a more significant preference for O2N3 binding. The relative band intensities suggest that O4 binding conformers comprise a larger portion of the population for [Ura+Ag]+ than [Ura+Cu]+. The dissociation behavior and relative stabilities of the [Ura+M]+ complexes, M+ = Cu+, Ag+, H+, and Na+) are examined via energy-resolved collision-induced dissociation experiments. The IRMPD spectra, dissociation behaviors, and binding preferences of Cu+ and Ag+ are compared with previous and present results for those of H+ and Na+. Graphical Abstract ᅟ.
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Affiliation(s)
- T E Akinyemi
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - R R Wu
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - Y-W Nei
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - N A Cunningham
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - H A Roy
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA
| | - J D Steill
- Institute for Molecules and Materials, FELIX Facility, Radboud University Nijmegen, Toernooiveld 7, 6525 ED, Nijmegen, The Netherlands
| | - G Berden
- Institute for Molecules and Materials, FELIX Facility, Radboud University Nijmegen, Toernooiveld 7, 6525 ED, Nijmegen, The Netherlands
| | - J Oomens
- Institute for Molecules and Materials, FELIX Facility, Radboud University Nijmegen, Toernooiveld 7, 6525 ED, Nijmegen, The Netherlands
- van't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
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Lamsabhi AM, Gutiérrez-Oliva S, Mó O, Toro-Labbé A, Yáñez M. Effects of the ionization in the tautomerism of uracil: A reaction electronic flux perspective. J Comput Chem 2015; 36:2135-45. [DOI: 10.1002/jcc.24054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 07/22/2015] [Accepted: 07/31/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento De Química C-13; Universidad Autónoma De Madrid; Cantoblanco 28049 Spain Madrid
| | - Soledad Gutiérrez-Oliva
- Facultad De Química, Nucleus Millennium Chemical Processes and Catalysis (CPC); Laboratorio De Química Teórica Computacional (QTC), Pontificia Universidad Católica De Chile; Santiago Chile
| | - Otilia Mó
- Departamento De Química C-13; Universidad Autónoma De Madrid; Cantoblanco 28049 Spain Madrid
| | - Alejandro Toro-Labbé
- Facultad De Química, Nucleus Millennium Chemical Processes and Catalysis (CPC); Laboratorio De Química Teórica Computacional (QTC), Pontificia Universidad Católica De Chile; Santiago Chile
| | - Manuel Yáñez
- Departamento De Química C-13; Universidad Autónoma De Madrid; Cantoblanco 28049 Spain Madrid
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12
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A theoretical study of the antioxidant properties of phenolic acid amides investigated through the radical-scavenging and metal chelation mechanisms. Eur Food Res Technol 2015. [DOI: 10.1007/s00217-015-2484-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Antioxidant Properties of Kanakugiol Revealed Through the Hydrogen Atom Transfer, Electron Transfer and M2+ (M2+ = Cu(II) or Co(II) Ion) Coordination Ability Mechanisms. A DFT Study In Vacuo and in Solution. FOOD BIOPHYS 2015. [DOI: 10.1007/s11483-015-9397-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wincel H. Hydration energies of protonated and sodiated thiouracils. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2014; 25:2134-2142. [PMID: 25270881 PMCID: PMC4221615 DOI: 10.1007/s13361-014-0987-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 08/13/2014] [Accepted: 08/19/2014] [Indexed: 06/03/2023]
Abstract
Hydration reactions of protonated and sodiated thiouracils (2-thiouracil, 6-methyl-2-thiouracil, and 4-thiouracil) generated by electrospray ionization have been studied in a gas phase at 10 mbar using a pulsed ion-beam high-pressure mass spectrometer. The thermochemical data, ΔH(o)n, ΔS(o)n, and ΔG(o)n, for the hydrated systems were obtained by equilibrium measurements. The water binding energies of protonated thiouracils, [2SU]H(+) and [6Me2SU]H(+), were found to be of the order of 51 kJ/mol for the first, and 46 kJ/mol for the second water molecule. For [4SU]H(+), these values are 3-4 kJ/mol lower. For sodiated complexes, these energies are similar for all studied systems, and varied between 62 and 68 kJ/mol for the first and between 48 and 51 kJ/mol for the second water molecule. The structural aspects of the precursors for hydrated complexes are discussed in conjunction with available literature data.
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Affiliation(s)
- Henryk Wincel
- Institute of Physical Chemistry, Polish Academy of Sciences, 01-224, Warsaw, Poland,
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Kabanda MM, Ebenso EE. Structures, Stabilization Energies, and Binding Energies of Quinoxaline···(H2O)n, Quinoxaline Dimer, and Quinoxaline···Cu Complexes: A Theoretical Study. J Phys Chem A 2013; 117:1583-95. [PMID: 23343309 DOI: 10.1021/jp309356b] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mwadham M. Kabanda
- Department of Chemistry, North-West University (Mafikeng Campus), Private Bag x2046, Mmabatho 2735,
South Africa
| | - Eno E. Ebenso
- Department of Chemistry, North-West University (Mafikeng Campus), Private Bag x2046, Mmabatho 2735,
South Africa
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16
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Brea O, Yáñez M, Mó O, Lamsabhi AM. On the stability of [(uracil)2-Cu]2+ complexes in the gas phase. Different pathways for the formation of [(uracil-H)(uracil)-Cu]+ monocations. Org Biomol Chem 2013; 11:3862-70. [DOI: 10.1039/c3ob40450a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Mammino L. Investigation of the antioxidant properties of hyperjovinol A through its Cu(II) coordination ability. J Mol Model 2012; 19:2127-42. [DOI: 10.1007/s00894-012-1684-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 11/06/2012] [Indexed: 11/28/2022]
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18
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Kabanda MM. Antioxidant Activity of Rooperol Investigated through Cu (I and II) Chelation Ability and the Hydrogen Transfer Mechanism: A DFT Study. Chem Res Toxicol 2012; 25:2153-66. [DOI: 10.1021/tx300244z] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Mwadham M. Kabanda
- Department of Chemistry, North-West University (Mafikeng Campus), Private Bag x 2046, Mmabatho 2735,
South Africa
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19
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Bacchus-Montabonel MC, Tergiman YS. Radiation damage on biomolecular systems: Dynamics of ion induced collision processes. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2011.11.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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LI PING, XIE XIAOYAN, BU YUXIANG, WANG WEIHUA, WANG NANA, SHI JUNYOU, MOU ZHAOXIA. THEORETICAL STUDIES ON THE COUPLING INTERACTIONS AND SELF-EXCHANGE REACTION MECHANISMS IN THE COMPLEXES OF NO WITH ONH AND NOH. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633608003848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The coupling interactions and self-exchange reaction mechanisms between NO and ONH (NOH) have been systematically investigated at the B3LYP/6-311++G** level of theory. All the equilibrium complexes are characterized by the intermolecular H-bonds and co-planar geometries. The cisoid NOH/ON species is the most stable one among all the complexes considered due to the formation of an N – N bond. Moreover, all the cisoid complexes are found to be more stable than the corresponding transoid ones. The origin of the blueshifts occurring in the selected complexes has been explored, employing the natural bond orbital (NBO) calculations. Additionally, the proton transfer mechanisms for the self-exchange reactions have been proposed, i.e. they can proceed via the three-center proton-coupled electron transfer or five-center cyclic proton-coupled electron transfer mechanism.
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Affiliation(s)
- PING LI
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
- Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Jinan 250100, P. R. China
| | - XIAOYAN XIE
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
| | - YUXIANG BU
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
- Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, Jinan 250100, P. R. China
- Institute of Theoretical Chemistry, Shandong University, Jinan 250100, P. R. China
| | - WEIHUA WANG
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
| | - NANA WANG
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
| | - JUNYOU SHI
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
| | - ZHAOXIA MOU
- College of Chemistry Science, Qufu Normal University, Qufu, 273165, P. R. China
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Li X, Chen J, Bowen KH. Photoelectron spectroscopic study of the negative ions of 4-thiouracil and 2,4-dithiouracil. J Chem Phys 2011; 134:074304. [DOI: 10.1063/1.3555177] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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22
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Xing D, Tan X, Jiang X, Wang B. Deprotonation studies of Cu+–guanine and Cu2+–guanine complexes by theoretical investigation. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2010.11.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Eizaguirre A, Mó O, Yáñez M, Boyd RJ. Effect of Sr2+association on the tautomerization processes of uracil and its dithio- and diseleno-derivatives. Org Biomol Chem 2011; 9:423-31. [DOI: 10.1039/c0ob00292e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Safi ZS, Lamsabhi AM. A theoretical density functional study of association of Zn2+with oxazolidine and its thio derivatives in the gas phase. J PHYS ORG CHEM 2010. [DOI: 10.1002/poc.1648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tintaru A, Charles L, Milko P, Roithová J, Schröder D. Redox reactions of copper(II) upon electrospray ionization in the presence of acridine ligands with an amide side chain. J PHYS ORG CHEM 2009. [DOI: 10.1002/poc.1459] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Salpin JY, Guillaumont S, Tortajada J, Lamsabhi AM. Gas-phase interactions between lead(II) ions and thiouracil nucleobases: a combined experimental and theoretical study. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2009; 20:359-69. [PMID: 19038555 DOI: 10.1016/j.jasms.2008.10.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 10/14/2008] [Accepted: 10/22/2008] [Indexed: 05/17/2023]
Abstract
The gas-phase interactions between lead(II) ions and 2-thiouracil, 4-thiouracil, and 2,4-dithiouracil have been investigated by combining mass spectrometry and theoretical calculations. The most abundant complexes observed, namely [Pb(thiouracil) - H](+), have been studied by MS/MS experiments. Cationization by the metal allows an unambiguous characterization of the sulfur position, several fragment ions being specific of each isomer. Moreover, compared with the uracil fragmentation, new fragmentation channels are observed: elimination of PbS or total reduction of the metal. Calculations performed on the different structures, including tautomers, show that sulfur is the preferred complexation site, suggesting the greater affinity of lead for sulfur. The most stable structures are always preferentially bidentate. Natural population analysis indicates a charge transfer from the base to the metal with a more pronounced covalent character for sulfur compared to oxygen. Energetic profiles associated with the main fragmentations have been described.
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Affiliation(s)
- Jean-Yves Salpin
- Université d'Evry Val d'Essonne, Laboratoire d'Analyse et Modélisation pour la Biologie et l'Environnement (LAMBE), Evry, France.
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Lamsabhi AM, Mó O, Gutiérrez-Oliva S, Pérez P, Toro-Labbé A, Yáñez M. The mechanism of double proton transfer in dimers of uracil and 2-thiouracil-The reaction force perspective. J Comput Chem 2009; 30:389-98. [DOI: 10.1002/jcc.21064] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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van der Wijst T, Fonseca Guerra C, Swart M, Bickelhaupt F, Lippert B. Rare Tautomers of 1-Methyluracil and 1-Methylthymine: Tuning Relative Stabilities through Coordination to PtIIComplexes. Chemistry 2009; 15:209-18. [DOI: 10.1002/chem.200801476] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Trujillo C, Mó O, Yáñez M. Why Are Selenouracils as Basic as but Stronger Acids than Uracil in the Gas Phase? Chemphyschem 2008; 9:1715-20. [DOI: 10.1002/cphc.200800215] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lamsabhi AM, Mó O, Yáñez M, Boyd RJ. Gas-Phase Interaction of Calcium (Ca2+) with Seleno Derivatives of Uracil. J Chem Theory Comput 2008; 4:1002-11. [DOI: 10.1021/ct800017j] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain, and Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3 Canada
| | - Otilia Mó
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain, and Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3 Canada
| | - Manuel Yáñez
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain, and Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3 Canada
| | - Russell J. Boyd
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain, and Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3 Canada
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Wang W, Wang N, Li P, Bu Y, Xie X, Song R. Theoretical studies on the properties of uracil and its dimer upon thioketo substitution. Theor Chem Acc 2008. [DOI: 10.1007/s00214-008-0442-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lamsabhi AM. Specific Hydration Effects on Oxo−Thio Triazepine Derivatives. J Phys Chem A 2008; 112:1791-7. [DOI: 10.1021/jp709960g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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Trujillo C, Mó O, Yáñez M. A theoretical study of hydration effects on the prototropic tautomerism of selenouracils. Org Biomol Chem 2007; 5:3092-9. [PMID: 17878967 DOI: 10.1039/b708045j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The prototropic tautomerism of 2-, 4-selenouracil and 2,4-diselenouracil has been studied using density functional theory (DFT) methods, at the B3LYP/6-311 + G(3df,2p)//B3LYP/6-31G(d,p) level. The relative stability order of selenouracil tautomers does not resemble that of uracil tautomers, but it is similar to that of thiouracils, even though the energy gaps between the different tautomers of selenouracils are smaller than for thiouracils. The tautomerism activation barriers are high enough as to conclude that only the oxo-selenone or the diselenone structures should be found in the gas phase. The specific interaction with one water molecule reduces these barriers by a half, but still the oxo-selenone form is always the most stable tautomer. The addition of a second water molecule has a relatively small effect, as well as bulk effects, evaluated by means of a continuum-polarized model. For isolated 2- and 4-selenouracils, the more favorable tautomerization process corresponds to a hydrogen transfer towards the selenium atom, the activation barriers for transfer towards the oxygen atom being much higher. This situation changes when specific and bulk effects are included, and the latter process becomes the more favorable one. For 2,4-diselenouracil the more favorable tautomerization, in the gas phase, corresponds to the H shift from N1 to the Se atom at C2, while solvation effects favor the transfer from N3 to the Se atom at C4.
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Affiliation(s)
- Cristina Trujillo
- Departamento de Química, C-9, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain
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Safi Z, Lamsabhi AM. Gas-phase reactivity of 2,7-dimethyl-[1,2,4]-triazepine thio derivatives toward Cu+ cation: a DFT study. J Phys Chem A 2007; 111:2213-9. [PMID: 17388292 DOI: 10.1021/jp068642h] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The gas-phase interactions of 2,7-dimethyl-[1,2,4]-triazepine and its thio derivatives with Cu+ were studied through the use of high-level density functional theory (DFT) calculations. The structure of all possible tautomers and their conformers was optimized at the B3LYP/6-31G(d) level of theory. Final energies were obtained at the B3LYP/6-311+G(2df,2p) level. It has been found that the direct association of Cu+ occurs at the oxygen atom attached to position 3 in the case of the dioxo derivative and at the sulfur atom in all other cases. For the dithio derivatives, the global minimum of the PES corresponds to the structure in which the metal ion bridges between the heteroatom at position 3 and the nitrogen atom at position 4 of the corresponding enolic tautomer, forming a four-membered ring structure; for the dioxo derivative, this conformer competes with the ketone tautomer. Moreover, the isomerization processes leading from the most stable adduct to the other stable conformers were investigated. Among all the considered compounds, the 3,5-dithiotriazepines-Cu+ is found to be the one that associates Cu+ more tightly in the gas phase. The calculated Cu+ binding energies show a good correlation with the experimental proton affinities.
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Affiliation(s)
- Zaki Safi
- Department of Chemistry, Faculty of Science, Al-Azhar University of Gaza, Gaza, Palestine
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Lamsabhi AM, Alcamí M, Mó O, Yáñez M, Tortajada J, Salpin JY. Unimolecular Reactivity of Uracil–Cu2+ Complexes in the Gas Phase. Chemphyschem 2007; 8:181-7. [PMID: 17154324 DOI: 10.1002/cphc.200600399] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The gas-phase interaction of copper(II) ions with uracil are studied by means of mass spectrometry and B3LYP/6-311+G(2df,2p)//B3LYP/6-31G(d) calculations. Positive-ion electrospray spectra show that the reaction of uracil with copper(II) gives rise to singly charged species, whereby the [Cu(uracil--H)](+) complex is the most intense ion in the spectra at low concentration. Mass spectrometry/mass spectrometry (MS/MS) experiments show that the loss of HNCO and NCO are the dominant fragmentation processes, accompanied by a minor loss of CO. A systematic study of the spectra obtained with different labeled species, namely, 2-(13)C- (m/z 175), 2-(13)C,1,3-(15)N(2)- (m/z 177) and 3-(15)N-uracil (m/z 175), concludes unambiguously that both the loss of HNCO and NCO involve exclusively C2 and N3, whereas only C4 is involved in the loss of CO. Suitable mechanisms for these fragmentation processes are proposed through a theoretical survey of the corresponding potential energy surface. In these mechanisms, pi complexes, which lie high in energy with respect to the global minimum, play a significant role in the loss of NCO; this explains why both products, HNCO and NCO involve the same atoms of the ring.
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Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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Lamsabhi AM, Alcamí M, Mó O, Yáñez M, Tortajada J. Gas-Phase Deprotonation of Uracil−Cu2+ and Thiouracil−Cu2+ Complexes. J Phys Chem A 2006; 110:1943-50. [PMID: 16451028 DOI: 10.1021/jp055163u] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The deprotonation of Cu2+ complexes with uracil, 2-thiouracil, 4-thiouracil, and 2,4-dithiouracil has been investigated by means of B3LYP/ 6-311+G(2df,2p)//6-31G(d) calculations. The most stable [(uracil-H)Cu]+ and [(thiouracil-H)Cu]+ complexes correspond to bidentate structures in which Cu interacts with the deprotonated ring-nitrogen atom and with the oxygen or the sulfur atom of the adjacent carbonyl or thiocarbonyl group. For 2- and 4-thiouracil derivatives, the structures in which the metal cation interacts with the thiocarbonyl group are clearly favored with respect to those in which Cu interacts with the carbonyl group. This is at variance with what was found to be the most stable structure of the corresponding Cu2+ complexes, where association to the carbonyl oxygen was always preferred over the association to the thiocarbonyl group. The [(uracil-H)Cu]+ and [(thiouracil-H)Cu]+ complexes can be viewed as the result of Cu+ attachment to the uracil-H and thiouracil-H radicals formed by the deprotonation of the corresponding uracil+* and thiouracil+* radical cations. As a matter of fact their relative stability is dictated by the intrinsic stability of the corresponding uracil-H and thiouracil-H radical and by the fact that, in general, the N3-deprotonated site is a better electron donor than the N1. In all complexes, the bonding of Cu both to nitrogen and sulfur and to nitrogen and oxygen has a significantly large covalent character.
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Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento de Química C-9, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain
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Aslanidis P, Cox PJ, Kaltzoglou A, Tsipis AC. An Experimental and Theoretical (DFT) Investigation of the Coordination Mode of 2,4-Dithiouracil (2,4-dtucH2) in Copper(I) Complexes with1,2-Bis(diphenylphosphanyl)benzene (dppbz): The Crystal Structures of [Cu(μ-Br)(dppbz)]2 and [CuBr(dppbz)(2,4-dtucH2)]. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200500726] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lamsabhi AM, Alcamí M, Mó O, Yáñez M, Tortajada J. Association of Cu2+with Uracil and Its Thio Derivatives: A Theoretical Study. Chemphyschem 2004; 5:1871-8. [PMID: 15648135 DOI: 10.1002/cphc.200400208] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The structures and relative stabilities of the complexes between Cu2+ and uracil, 2-thiouracil, 4-thiouracil, and 2,4-dithiouracil were investigated by B3LYP/6-311+G(2df,2p)//B3LYP/6-31G* DFT calculations. In those systems in which both types of basic centers, that is, a carbonyl and a thiocarbonyl group, are present, association of Cu2+ with the oxygen atom is systematically favored, in contrast to what was found for the corresponding Cu+ complexes. This can be understood by considering that association of Cu2+ is immediately followed by oxidation of the base, which accumulates the negative charge at the oxygen atoms. Similarly, for 2,4-dithiouracil the most basic site for Cu+ attachment is the sulfur atom at the 4-position, while for association of Cu2+ it is sulfur at the 2-position. In contrast, differences between uracil-Cu+ and uracil-Cu2+ complexes are very small, and in both cases the oxygen atom at the 4-position is the most basic. Cu2+ binding energies are about 4 and 1.2 times larger than Cu+ binding energies and proton affinities, respectively. Uracil- and thiouracil-Cu2+ complexes are thermodynamically unstable but kinetically stable with respect to their dissociation into uracil*+ + Cu+ or thiouracil*+ + Cu+. The Cu2+ binding energies vary with the difference between the second ionization potential of the metal and the first ionization potential of the base. regardless of the reference acid (H+, Cu+, Cu2+) the basicity trend is 2,4-dithiouracil > 4-thiouracil > 2-thiouracil > uracil.
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Affiliation(s)
- Al Mokhtar Lamsabhi
- Departamento de Química C-9, Facultad de Ciencias Universidad Autónoma de Madrid Cantoblanco, 28049 Madrid, Spain
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