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Chatgilialoglu C, Barata-Vallejo S, Gimisis T. Radical Reactions in Organic Synthesis: Exploring in-, on-, and with-Water Methods. Molecules 2024; 29:569. [PMID: 38338314 PMCID: PMC10856544 DOI: 10.3390/molecules29030569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024] Open
Abstract
Radical reactions in water or aqueous media are important for organic synthesis, realizing high-yielding processes under non-toxic and environmentally friendly conditions. This overview includes (i) a general introduction to organic chemistry in water and aqueous media, (ii) synthetic approaches in, on, and with water as well as in heterogeneous phases, (iii) reactions of carbon-centered radicals with water (or deuterium oxide) activated through coordination with various Lewis acids, (iv) photocatalysis in water and aqueous media, and (v) synthetic applications bioinspired by naturally occurring processes. A wide range of chemical processes and synthetic strategies under different experimental conditions have been reviewed that lead to important functional group translocation and transformation reactions, leading to the preparation of complex molecules. These results reveal how water as a solvent/medium/reagent in radical chemistry has matured over the last two decades, with further discoveries anticipated in the near future.
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Affiliation(s)
- Chryssostomos Chatgilialoglu
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Center of Advanced Technologies, Adam Mickiewicz University, 61-712 Poznan, Poland
| | - Sebastian Barata-Vallejo
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Facultad de Farmacia y Bioquímica, Departamento de Ciencias Químicas, Universidad de Buenos Aires, Junin 954, Buenos Aires CP 1113, Argentina
| | - Thanasis Gimisis
- Department of Chemistry, National and Kapodistrian University of Athens, 15771 Athens, Greece
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2
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Krokidis MG, Prasinou P, Efthimiadou EK, Boari A, Ferreri C, Chatgilialoglu C. Effects of Aging and Disease Conditions in Brain of Tumor-Bearing Mice: Evaluation of Purine DNA Damages and Fatty Acid Pool Changes. Biomolecules 2022; 12:1075. [PMID: 36008969 PMCID: PMC9405824 DOI: 10.3390/biom12081075] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 02/04/2023] Open
Abstract
The consequences of aging and disease conditions in tissues involve reactive oxygen species (ROS) and related molecular alterations of different cellular compartments. We compared a murine model of immunodeficient (SCID) xenografted young (4 weeks old) and old (17 weeks old) mice with corresponding controls without tumor implantation and carried out a compositional evaluation of brain tissue for changes in parallel DNA and lipids compartments. DNA damage was measured by four purine 5',8-cyclo-2'-deoxynucleosides, 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG), and 8-oxo-7,8-dihydro-2'-deoxyadenosine (8-oxo-dA). In brain lipids, the twelve most representative fatty acid levels, which were mostly obtained from the transformation of glycerophospholipids, were followed up during the aging and disease progressions. The progressive DNA damage due to age and tumoral conditions was confirmed by raised levels of 5'S-cdG and 5'S-cdA. In the brain, the remodeling involved a diminution of palmitic acid accompanied by an increase in arachidonic acid, along both age and tumor progressions, causing increases in the unsaturation index, the peroxidation index, and total TFA as indicators of increased oxidative and free radical reactivity. Our results contribute to the ongoing debate on the central role of DNA and genome instability in the aging process, and on the need for a holistic vision, which implies choosing the best biomarkers for such monitoring. Furthermore, our data highlight brain tissue for its lipid remodeling response and inflammatory signaling, which seem to prevail over the effects of DNA damage.
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Affiliation(s)
- Marios G. Krokidis
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research “Demokritos”, 15310 Athens, Greece
| | - Paraskevi Prasinou
- Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy
| | - Eleni K. Efthimiadou
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research “Demokritos”, 15310 Athens, Greece
- Department of Chemistry, National and Kapodistrian University of Athens, 15784 Athens, Greece
| | - Andrea Boari
- Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy
| | - Carla Ferreri
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy
| | - Chryssostomos Chatgilialoglu
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, Via Piero Gobetti 101, 40129 Bologna, Italy
- Center for Advanced Technologies, Adam Mickiewicz University, 61-614 Poznan, Poland
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3
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Roignant M, Zhang J, Brioche J, Piettre SR. Second Generation Synthesis of Modified Dinucleotide Analogues Featuring a Difluorophosphin(othio)yl Linkage. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Matthieu Roignant
- Department of Chemistry University of Rouen COBRA-UMR 6014 CNRS F-76131 Mont Saint Aignan cedex France
| | - Jun Zhang
- Department of Chemistry University of Rouen COBRA-UMR 6014 CNRS F-76131 Mont Saint Aignan cedex France
| | - Julien Brioche
- Department of Chemistry University of Rouen COBRA-UMR 6014 CNRS F-76131 Mont Saint Aignan cedex France
| | - Serge R. Piettre
- Department of Chemistry University of Rouen COBRA-UMR 6014 CNRS F-76131 Mont Saint Aignan cedex France
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Bell M, Kumar A, Sevilla MD. Electron-Induced Repair of 2'-Deoxyribose Sugar Radicals in DNA: A Density Functional Theory (DFT) Study. Int J Mol Sci 2021; 22:ijms22041736. [PMID: 33572317 PMCID: PMC7916153 DOI: 10.3390/ijms22041736] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/01/2021] [Accepted: 02/05/2021] [Indexed: 12/19/2022] Open
Abstract
In this work, we used ωB97XD density functional and 6-31++G** basis set to study the structure, electron affinity, populations via Boltzmann distribution, and one-electron reduction potentials (E°) of 2′-deoxyribose sugar radicals in aqueous phase by considering 2′-deoxyguanosine and 2′-deoxythymidine as a model of DNA. The calculation predicted the relative stability of sugar radicals in the order C4′• > C1′• > C5′• > C3′• > C2′•. The Boltzmann distribution populations based on the relative stability of the sugar radicals were not those found for ionizing radiation or OH-radical attack and are good evidence the kinetic mechanisms of the processes drive the products formed. The adiabatic electron affinities of these sugar radicals were in the range 2.6–3.3 eV which is higher than the canonical DNA bases. The sugar radicals reduction potentials (E°) without protonation (−1.8 to −1.2 V) were also significantly higher than the bases. Thus the sugar radicals will be far more readily reduced by solvated electrons than the DNA bases. In the aqueous phase, these one-electron reduced sugar radicals (anions) are protonated from solvent and thus are efficiently repaired via the “electron-induced proton transfer mechanism”. The calculation shows that, in comparison to efficient repair of sugar radicals by the electron-induced proton transfer mechanism, the repair of the cyclopurine lesion, 5′,8-cyclo-2′-dG, would involve a substantial barrier.
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5
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Chatgilialoglu C, Krokidis MG, Masi A, Barata-Vallejo S, Ferreri C, Terzidis MA, Szreder T, Bobrowski K. New Insights into the Reaction Paths of Hydroxyl Radicals with Purine Moieties in DNA and Double-Stranded Oligodeoxynucleotides. Molecules 2019; 24:molecules24213860. [PMID: 31717733 PMCID: PMC6865195 DOI: 10.3390/molecules24213860] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 11/21/2022] Open
Abstract
The reaction of hydroxyl radical (HO•) with DNA produces many primary reactive species and many lesions as final products. In this study, we have examined the optical spectra of intermediate species derived from the reaction of HO• with a variety of single- and double-stranded oligodeoxynucleotides and ct-DNA in the range of 1 μs to 1 ms by pulse radiolysis using an Intensified Charged Coupled Device (ICCD) camera. Moreover, we applied our published analytical protocol based on an LC-MS/MS system with isotopomeric internal standards to enable accurate and precise measurements of purine lesion formation. In particular, the simultaneous measurement of the four purine 5′,8-cyclo-2′-deoxynucleosides (cPu) and two 8-oxo-7,8-dihydro-2′-deoxypurine (8-oxo-Pu) was obtained upon reaction of genetic material with HO• radicals generated either by γ-radiolysis or Fenton-type reactions. Our results contributed to the debate in the literature regarding absolute level of lesions, method of HO• radical generation, 5′R/5′S diastereomeric ratio in cPu, and relative abundance between cPu and 8-oxo-Pu.
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Affiliation(s)
- Chryssostomos Chatgilialoglu
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy; (M.G.K.); (A.M.); (C.F.); (M.A.T.)
- Center for Advanced Technologies, Adam Mickiewicz University, 61-614 Poznań, Poland
- Correspondence: (C.C.); (K.B.); Tel.: +39-051-6398309 (C.C.)
| | - Marios G. Krokidis
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy; (M.G.K.); (A.M.); (C.F.); (M.A.T.)
- Institute of Nanoscience and Nanotechnology, N.C.S.R. “Demokritos”, 15310 Agia Paraskevi Attikis, Greece
| | - Annalisa Masi
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy; (M.G.K.); (A.M.); (C.F.); (M.A.T.)
| | - Sebastian Barata-Vallejo
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy; (M.G.K.); (A.M.); (C.F.); (M.A.T.)
- Departamento de Quimíca Organíca, Facultad de Farmacia y Bioquimíca, Universidad de Buenos Aires, Junin 954, Buenos Aires CP 1113, Argentina
| | - Carla Ferreri
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy; (M.G.K.); (A.M.); (C.F.); (M.A.T.)
| | - Michael A. Terzidis
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy; (M.G.K.); (A.M.); (C.F.); (M.A.T.)
- Centre of Radiation Research and Technology, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland;
| | - Tomasz Szreder
- Centre of Radiation Research and Technology, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland;
| | - Krzysztof Bobrowski
- Centre of Radiation Research and Technology, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland;
- Correspondence: (C.C.); (K.B.); Tel.: +39-051-6398309 (C.C.)
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6
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5',8-Cyclopurine Lesions in DNA Damage: Chemical, Analytical, Biological, and Diagnostic Significance. Cells 2019; 8:cells8060513. [PMID: 31141888 PMCID: PMC6628319 DOI: 10.3390/cells8060513] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 05/18/2019] [Accepted: 05/22/2019] [Indexed: 12/14/2022] Open
Abstract
Purine 5′,8-cyclo-2′-deoxynucleosides (cPu) are tandem-type lesions observed among the DNA purine modifications and identified in mammalian cellular DNA in vivo. These lesions can be present in two diasteroisomeric forms, 5′R and 5′S, for each 2′-deoxyadenosine and 2′-deoxyguanosine moiety. They are generated exclusively by hydroxyl radical attack to 2′-deoxyribose units generating C5′ radicals, followed by cyclization with the C8 position of the purine base. This review describes the main recent achievements in the preparation of the cPu molecular library for analytical and DNA synthesis applications for the studies of the enzymatic recognition and repair mechanisms, their impact on transcription and genetic instability, quantitative determination of the levels of lesions in various types of cells and animal model systems, and relationships between the levels of lesions and human health, disease, and aging, as well as the defining of the detection limits and quantification protocols.
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Diastereomeric Recognition of 5',8-cyclo-2'-Deoxyadenosine Lesions by Human Poly(ADP-ribose) Polymerase 1 in a Biomimetic Model. Cells 2019; 8:cells8020116. [PMID: 30717407 PMCID: PMC6406461 DOI: 10.3390/cells8020116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/20/2019] [Accepted: 02/01/2019] [Indexed: 12/21/2022] Open
Abstract
5’,8-Cyclo-2’-deoxyadenosine (cdA), in the 5’R and 5’Sdiastereomeric forms, are typical non strand-break oxidative DNA lesions, induced by hydroxyl radicals, with emerging importance as a molecular marker. These lesions are exclusively repaired by the nucleotide excision repair (NER) mechanism with a low efficiency, thus readily accumulating in the genome. Poly(ADP-ribose) polymerase1 (PARP1) acts as an early responder to DNA damage and plays a key role as a nick sensor in the maintenance of the integrity of the genome by recognizing nicked DNA. So far, it was unknown whether the two diastereomeric cdA lesions could induce specific PARP1 binding. Here, we provide the first evidence of PARP1 to selectively recognize the diastereomeric lesions of 5’S-cdA and 5’R-cdA in vitro as compared to deoxyadenosine in model DNA substrates (23-mers) by using circular dichroism, fluorescence spectroscopy, immunoblotting analysis, and gel mobility shift assay. Several features of the recognition of the damaged and undamaged oligonucleotides by PARP1 were characterized. Remarkably, PARP1 exhibits different affinities in binding to a double strand (ds) oligonucleotide, which incorporates cdA lesions in R and S diastereomeric form. In particular, PARP1 proved to bind oligonucleotides, including a 5’S-cdA, with a higher affinity constant for the 5’S lesion in a model of ds DNA than 5’R-cdA, showing different recognition patterns, also compared with undamaged dA. This new finding highlights the ability of PARP1 to recognize and differentiate the distorted DNA backbone in a biomimetic system caused by different diastereomeric forms of a cdA lesion.
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Shaik R, Ellis MW, Starr MJ, Amato NJ, Bryant-Friedrich AC. Photochemical Generation of a C5′-Uridinyl Radical. Chembiochem 2015; 16:2379-84. [DOI: 10.1002/cbic.201500330] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Raziya Shaik
- Unicon Pharma, Inc.; 2015 Lincoln Highway Suite 234 Edison NJ 08817 USA
| | - Matthew W. Ellis
- Department of Medicinal and Biological Chemistry; The University of Toledo; 2801 W Bancroft Street MS 606 Toledo OH 43606 USA
| | - Matthew J. Starr
- Department of Medicinal and Biological Chemistry; The University of Toledo; 2801 W Bancroft Street MS 606 Toledo OH 43606 USA
| | - Nicholas J. Amato
- Department of Chemistry; The University of California, Riverside; 501 Big Springs Road Riverside CA 92521 USA
| | - Amanda C. Bryant-Friedrich
- Department of Medicinal and Biological Chemistry; The University of Toledo; 2801 W Bancroft Street MS 606 Toledo OH 43606 USA
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Rak J, Chomicz L, Wiczk J, Westphal K, Zdrowowicz M, Wityk P, Żyndul M, Makurat S, Golon Ł. Mechanisms of Damage to DNA Labeled with Electrophilic Nucleobases Induced by Ionizing or UV Radiation. J Phys Chem B 2015; 119:8227-38. [PMID: 26061614 DOI: 10.1021/acs.jpcb.5b03948] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Hypoxia--a hallmark of solid tumors--makes hypoxic cells radioresistant. On the other hand, DNA, the main target of anticancer therapy, is not sensitive to the near UV photons and hydrated electrons, one of the major products of water radiolysis under hypoxic conditions. A possible way to overcome these obstacles to the efficient radio- and photodynamic therapy of cancer is to sensitize the cellular DNA to electrons and/or ultraviolet radiation. While incorporated into genomic DNA, modified nucleosides, 5-bromo-2'-deoxyuridine in particular, sensitize cells to both near-ultraviolet photons and γ rays. It is believed that, in both sensitization modes, the reactive nucleobase radical is formed as a primary product which swiftly stabilizes, leading to serious DNA damage, like strand breaks or cross-links. However, despite the apparent similarity, such radio- and photosensitization of DNA seems to be ruled by fundamentally different mechanisms. In this review, we demonstrate that the most important factors deciding on radiodamage to the labeled DNA are (i) the electron affinity (EA) of modified nucleoside (mNZ), (ii) the local surroundings of the label that significantly influences the EA of mNZ, and (iii) the strength of the chemical bond holding together the substituent and a nucleobase. On the other hand, we show that the UV damage to sensitized DNA is governed by long-range photoinduced electron transfer, the efficiency of which is controlled by local DNA sequences. A critical review of the literature mechanisms concerning both types of damage to the labeled biopolymer is presented. Ultimately, the perspectives of studies on DNA sensitization in the context of cancer therapy are discussed.
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Affiliation(s)
- Janusz Rak
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Lidia Chomicz
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Justyna Wiczk
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Kinga Westphal
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Magdalena Zdrowowicz
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Paweł Wityk
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Michał Żyndul
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Samanta Makurat
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Łukasz Golon
- Faculty of Chemistry University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
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10
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Zdrowowicz M, Chomicz L, Miloch J, Wiczk J, Rak J, Kciuk G, Bobrowski K. Reactivity pattern of bromonucleosides induced by 2-hydroxypropyl radicals: photochemical, radiation chemical, and computational studies. J Phys Chem B 2015; 119:6545-54. [PMID: 25971814 DOI: 10.1021/acs.jpcb.5b01904] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The bromonucleosides (BrdX's) 5-bromo-2'-deoxyuridine (BrdU), 5-bromo-2'-deoxycytidine (BrdC), 8-bromo-2'-deoxyadenosine (BrdA), and 5-bromo-2'-deoxyguanosine (BrdG) may substitute for ordinary nucleosides in DNA. As indicated by electron-stimulated desorption experiments, such a modified biopolymer is greater than 2-3-fold more sensitive to damage induced by excess electrons. The other major product of water radiolysis, the (•)OH radical, may form a number of other radicals in chemical reactions with the complex content of the cell. Thus, the well-proved BrdU-labeled DNA radiosensitivity may be, at least in part, related to secondary organic radicals. Therefore, in the current study, the propensity of BrdX's to damage induced by 2-hydroxypropyl radical (OHisop(•))-a prototype radical species-was investigated. The HPLC and LC-MS analyses revealed the formation of two major products from the brominated pyrimidine nucleosides, a native nucleoside and an adduct of BrdX and OHisop(•) , and only an adduct of BrdX from the bromopurine nucleosides. Quantum chemical calculations ascribed this evident difference between purines and pyrimidines to the electron transfer from OHisop(•) to BrdX that is especially favorable in pyrimidines.
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Affiliation(s)
- Magdalena Zdrowowicz
- †Faculty of Chemistry, University of Gdañsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Lidia Chomicz
- †Faculty of Chemistry, University of Gdañsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Justyna Miloch
- †Faculty of Chemistry, University of Gdañsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Justyna Wiczk
- †Faculty of Chemistry, University of Gdañsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Janusz Rak
- †Faculty of Chemistry, University of Gdañsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Gabriel Kciuk
- ‡Centre of Radiation Research and Technology, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland
| | - Krzysztof Bobrowski
- ‡Centre of Radiation Research and Technology, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland
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11
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Zhao J, Wang M, Fu A, Yang H, Bu Y. Hydrated Electron Transfer to Nucleobases in Aqueous Solutions Revealed by Ab Initio Molecular Dynamics Simulations. Chemphyschem 2015; 16:2348-56. [DOI: 10.1002/cphc.201500040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Indexed: 11/07/2022]
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12
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Westphal K, Wiczk J, Miloch J, Kciuk G, Bobrowski K, Rak J. Irreversible electron attachment – a key to DNA damage by solvated electrons in aqueous solution. Org Biomol Chem 2015; 13:10362-9. [DOI: 10.1039/c5ob01542a] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In an aqueous solution trinucleotides labeled with bromonucleobases are damaged by ionizing radiation induced electrons while native trimers are insensitive to electrons under the same conditions.
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Affiliation(s)
- K. Westphal
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
| | - J. Wiczk
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
| | - J. Miloch
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
| | - G. Kciuk
- Centre of Radiation Research and Technology
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw
- Poland
| | - K. Bobrowski
- Centre of Radiation Research and Technology
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw
- Poland
| | - J. Rak
- Faculty of Chemistry
- University of Gdańsk
- 80-308 Gdańsk
- Poland
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13
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Wieczór M, Wityk P, Czub J, Chomicz L, Rak J. A first-principles study of electron attachment to the fully hydrated bromonucleobases. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.01.052] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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Chomicz L, Furmanchuk A, Leszczynski J, Rak J. Electron induced single strand break and cyclization: a DFT study on the radiosensitization mechanism of the nucleotide of 8-bromoguanine. Phys Chem Chem Phys 2014; 16:6568-74. [PMID: 24569645 DOI: 10.1039/c3cp55411b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cleavage of the O-P bond in 8-bromo-2'-deoxyguanosine-3',5'-diphosphate (BrdGDP), considered as a model of single strand break (SSB) in labelled double-stranded DNA (ds DNA), is investigated at the B3LYP/6-31++G(d,p) level. The thermodynamic and kinetic characteristics of the formation of SSB are compared to those related to the 5',8-cycloguanosine lesion. The first reaction step, common to both damage types, which is the formation of the reactive guanyl radical, proceeds with a barrier-free or low-barrier release of the bromide anion. The guanyl radical is then stabilized by hydrogen atom transfer from the C3' or C5' sites of the 2'-deoxyribose moiety to its C8 center. The C3' path, via the O-P bond cleavage, leads to a ketone derivative (the SSB model), while the C5' path is more likely to yield 5',8-cycloguanosine.
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Affiliation(s)
- Lidia Chomicz
- Department of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland.
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15
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Chomicz L, Leszczynski J, Rak J. Electron-Induced Degradation of 8-Bromo-2′-deoxyadenosine 3′,5′-Diphosphate, a DNA Radiosensitizing Nucleotide. J Phys Chem B 2013; 117:8681-8. [DOI: 10.1021/jp4022689] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lidia Chomicz
- Department
of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952
Gdańsk, Poland
| | - Jerzy Leszczynski
- Interdisciplinary
Nanotoxicity
Center, Jackson State University, Jackson,
Mississippi, 39217, United States
| | - Janusz Rak
- Department
of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952
Gdańsk, Poland
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Recent advances in cyclonucleosides: C-cyclonucleosides and spore photoproducts in damaged DNA. Molecules 2012; 17:11630-54. [PMID: 23023688 PMCID: PMC6268316 DOI: 10.3390/molecules171011630] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 09/25/2012] [Accepted: 09/26/2012] [Indexed: 12/04/2022] Open
Abstract
Cyclonucleosides which are fixed in a specific conformation around the glycosyl bond by a carbon and heteroatom chain constitute a unique category of nucleoside derivatives. Because they are structural analogs, cyclonucleosides and oligodeoxynucleotides containing them would be useful tools for investigating the biological functions and conformations of DNA, RNA as well as their steric interactions with proteins. C-Cyclonucleosides bridged by a carbon chain between the base and sugar moieties are the most attractive from the synthetic points of view as well as for use as biological tools. In this review, recent progress of the synthesis of C-cyclonucleosides is surveyed. Among the C-cyclonucleosides, 5′,8-C-cyclodeoxyadenosine is one of the well-known derivatives of which the first practical synthesis was reported over 30 years ago. Recently, 5′,8-C-cyclodeoxyadenosine has attracted considerable interest as a biomarker, since its formation in oxidatively-damaged DNA is considered to be related to various diseases and aging. Another important analogue of cyclonucleosides is a unique thymidine phosphate dimer, a so-called spore photoproduct, which has been found in photo-damaged DNA. Recent advances in the synthesis, mechanism-studies, and stereochemical preference of repairing enzymes related to 5′,8-C-cyclodeoxyadenosine and spore photoproducts are also reviewed.
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Zaliznyak T, Lukin M, de los Santos C. Structure and stability of duplex DNA containing (5'S)-5',8-cyclo-2'-deoxyadenosine: an oxidatively generated lesion repaired by NER. Chem Res Toxicol 2012; 25:2103-11. [PMID: 22928555 DOI: 10.1021/tx300193k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cellular respiration and ionizing radiation generate 5',8-cyclo-2'-deoxyribonucleosides, a special type of DNA damage that involves two modifications in the same nucleotide. These lesions evade the action of base excision glycosylases, and their removal is a function of the nucleotide excision repair pathway. Diastereomeric 5',8-cyclo-2'-deoxyadenosine blocks mammalian DNA replication, diminishes the levels of DNA transcription, and induces transcriptional mutagenesis. Using solution state NMR spectroscopy and restrained molecular dynamics simulations, we have determined the structure of an undecameric DNA duplex having a centrally located (5'S)-5',8-cyclo-2'-deoxyadenosine residue paired to T. The damaged duplex structure is a right-handed helix having Watson-Crick base-pair alignments throughout, and 2-deoxyribose puckers within the B-form conformation. Only small structural perturbations are observed at the lesion-containing and 5'-flanking base pair. The 2-deoxyribose of the damaged nucleotide adopts the O4'-exo conformation, and the S-cdA·T base pair is propeller twisted. The 5'-lesion-flanking base is tilted forming a significantly buckled base pair with its partner guanine. Analysis of UV-melting curves indicates mild thermal and thermodynamic destabilization on the damaged duplex. The S-cdA·T duplex structure shows many similarities to and some intriguing differences from the recently reported structure of an S-cdG·dC duplex³¹ that suggest different lesion site dynamics.
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Affiliation(s)
- Tatiana Zaliznyak
- Department of Pharmacological Sciences, School of Medicine, Stony Brook University, Stony Brook, New York 11794-8651, USA
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Park Y, Polska K, Rak J, Wagner JR, Sanche L. Fundamental mechanisms of DNA radiosensitization: damage induced by low-energy electrons in brominated oligonucleotide trimers. J Phys Chem B 2012; 116:9676-82. [PMID: 22812492 DOI: 10.1021/jp304964r] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The replacement of nucleobases with brominated analogs enhances DNA radiosensitivity. We examine the chemistry of low-energy electrons (LEEs) in this sensitization process by experiments with thin films of the oligonucleotide trimers TBrXT, where BrX = 5-BrU (5-bromouracil), 5-BrC (5-bromocytosine), 8-BrA (8-bromoadenine), or 8-BrG (8-bromoguanine). The products induced from irradiation of thin (∼ 2.5 nm) oligonucleotide films, with 10 eV electrons, under ultrahigh vacuum (UHV) are analyzed by HPLC-UV. The number of damaged brominated trimers ranges from about 12 to 15 × 10(-3) molecules per incident electron, whereas under the identical conditions, these numbers drop to 4-7 × 10(-3) for the same, but nonbrominated oligonucleotides. The results of HPLC analysis show that the main degradation pathway of trinucleotides containing brominated bases involve debromination (i.e., loss of the bromine atom and its replacement with a hydrogen atom). The electron-induced sum of products upon bromination increases by factors of 2.1 for the pyrimidines and 3.2 for the purines. Thus, substitution of any native nucleobase with a brominated one in simple models of DNA increases LEE-induced damage to DNA and hence its radiosensitivity. Furthermore, besides the brominated pyrimidines that have already been tested in clinical trials, brominated purines not only appear to be promising sensitizers for radiotherapy, but could provide a higher degree of radiosensitization.
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Affiliation(s)
- Yeunsoo Park
- Center for Radiobiology and Radiotherapy, Department of Nuclear Medicine and Radiobiology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Québec, Canada J1H 5N4
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Kumar A, Pottiboyina V, Sevilla MD. One-electron oxidation of neutral sugar radicals of 2'-deoxyguanosine and 2'-deoxythymidine: a density functional theory (DFT) study. J Phys Chem B 2012; 116:9409-16. [PMID: 22793263 DOI: 10.1021/jp3059068] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One electron oxidation of neutral sugar radicals has recently been suggested to lead to important intermediates in the DNA damage process culminating in DNA strand breaks. In this work, we investigate sugar radicals in a DNA model system to understand the energetics of sugar radical formation and oxidation. The geometries of neutral sugar radicals C(1')(•), C(2')(•), C(3')(•), C(4')(•), and C(5')(•) of 2'-deoxyguanosine (dG) and 2'-deoxythymidine (dT) were optimized in the gas phase and in solution using the B3LYP and ωB97x functionals and 6-31++G(d) basis set. Their corresponding cations (C(1')(+), C(2')(+), C(3')(+), C(4')(+), and C(5')(+)) were generated by removing an electron (one-electron oxidation) from the neutral sugar radicals, and their geometries were also optimized using the same methods and basis set. The calculation predicts the relative stabilities of the neutral sugar radicals in the order C(1')(•) > C(4')(•) > C(5')(•) > C(3')(•) > C(2')(•), respectively. Of the neutral sugar radicals, C(1')(•) has the lowest vertical ionization potential (IP(vert)), ca. 6.33 eV in the gas phase and 4.71 eV in solution. C(2')(•) has the highest IP(vert), ca. 8.02 eV, in the gas phase, and the resultant C(2') cation is predicted to undergo a barrierless hydride transfer from the C(1') site to produce the C(1') cation. One electron oxidation of C(2')(•) in dG is predicted to result in a low lying triplet state consisting of G(+•) and C(2')(•). The 5',8-cyclo-2'-deoxyguanosin-7-yl radical formed by intramolecular bonding between C(5')(•) and C(8) of guanine transfers spin density from C(5') site to guanine, and this structure has IP(vert) 6.25 and 5.48 eV in the gas phase and in solution.
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Affiliation(s)
- Anil Kumar
- Department of Chemistry, Oakland University, Rochester, Michigan 48309, USA
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20
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Abstract
Endogenous and exogenous sources cause free radical-induced DNA damage in living organisms by a variety of mechanisms. The highly reactive hydroxyl radical reacts with the heterocyclic DNA bases and the sugar moiety near or at diffusion-controlled rates. Hydrated electron and H atom also add to the heterocyclic bases. These reactions lead to adduct radicals, further reactions of which yield numerous products. These include DNA base and sugar products, single- and double-strand breaks, 8,5'-cyclopurine-2'-deoxynucleosides, tandem lesions, clustered sites and DNA-protein cross-links. Reaction conditions and the presence or absence of oxygen profoundly affect the types and yields of the products. There is mounting evidence for an important role of free radical-induced DNA damage in the etiology of numerous diseases including cancer. Further understanding of mechanisms of free radical-induced DNA damage, and cellular repair and biological consequences of DNA damage products will be of outmost importance for disease prevention and treatment.
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Affiliation(s)
- Miral Dizdaroglu
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
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21
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Chomicz L, Rak J, Storoniak P. Electron-induced elimination of the bromide anion from brominated nucleobases. A computational study. J Phys Chem B 2012; 116:5612-9. [PMID: 22510158 DOI: 10.1021/jp3008738] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The enhancement of radiodamage to DNA labeled with halonucleobases is attributed to the reactive radical produced from a halonucleobase by the attachment of an electron. We examined at the B3LYP/6-31++G** level electron capture by four brominated nucleobases (BrNBs): 8-bromo-9-methyladenine, 8-bromo-9-methylguanine, 5-bromo-1-methylcytosine, and 5-bromo-1-methyluracil followed by the release of the bromide anion and a nucleobase radical. We demonstrate that neutral BrNBs in both gas and aqueous phases are better electron acceptors than unsubstituted NBs and that resulting anion radicals, BrNBs(•-), can easily transform into the product complex of the bromide anion and the nucleobase radical ([Br(-)···NB(•)]). The overall thermodynamic stimulus for the process starting with the neutral BrNB and ending with the isolated bromide anion and the NB(•) radical is similar in the case of all four BrNBs studied, which suggests their comparable radiosensitizing capabilities.
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Affiliation(s)
- Lidia Chomicz
- Department of Chemistry, University of Gdańsk , Sobieskiego 18, 80-952 Gdańsk, Poland
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22
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Audat SAS, Love CT, Al-Oudat BAS, Bryant-Friedrich AC. Synthesis of C3' modified nucleosides for selective generation of the C3'-deoxy-3'-thymidinyl radical: a proposed intermediate in LEE induced DNA damage. J Org Chem 2012; 77:3829-37. [PMID: 22468713 DOI: 10.1021/jo300045m] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
DNA damage pathways induced by low-energy electrons (LEEs) are believed to involve the formation of 2-deoxyribose radicals. These radicals, formed at the C3' and C5' positions of nucleotides, are the result of cleavage of the C-O phosphodiester bond through transfer of LEEs to the phosphate group of DNA oligomers from the nucleobases. A considerable amount of information has been obtained to illuminate the identity of the unmodified oligonucleotide products formed through this process. There exists, however, a paucity of information as to the nature of the modified lesions formed from degradation of these sugar radicals. To determine the identity of the damage products formed via the 2',3'-dideoxy-C3'-thymidinyl radical (C3'(dephos) sugar radical), phenyl selenide and acyl modified sugar and nucleoside derivatives have been synthesized, and their suitability as photochemical precursors of the radical of interest has been evaluated. Upon photochemical activation of C3'-derivatized nucleosides in the presence of the hydrogen atom donor tributyltin hydride, 2',3'-dideoxythymidine is formed indicating the selective generation of the C3'(dephos) sugar radical. These precursors will make the identification and quantification of products of DNA damage derived from radicals generated by LEEs possible.
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Affiliation(s)
- Suaad A S Audat
- Department of Medicinal and Biological Chemistry, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, USA
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23
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Polska K, Rak J, Bass AD, Cloutier P, Sanche L. Electron stimulated desorption of anions from native and brominated single stranded oligonucleotide trimers. J Chem Phys 2012; 136:075101. [PMID: 22360262 PMCID: PMC3813477 DOI: 10.1063/1.3685587] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
We measured the low energy electron stimulated desorption (ESD) of anions from thin films of native (TXT) and bromine monosubstituted (TBrXT) oligonucleotide trimers deposited on a gold surface (T = thymidine, X = T, deoxycytidine (C), deoxyadenosine (A) or deoxyguanosine (G), Br = bromine). The desorption of H(-), CH(3)(-)/NH(-), O(-)/NH(2)(-), OH(-), CN(-), and Br(-) was induced by 0 to 20 eV electrons. Dissociative electron attachment, below 12 eV, and dipolar dissociation, above 12 eV, are responsible for the formation of these anions. The comparison of the results obtained for the native and brominated trimers suggests that the main pathways of TBrXT degradation correspond to the release of the hydride and bromide anions. Significantly, the presence of bromine in oligonucleotide trimers blocks the electron-induced degradation of nuclobases as evidenced by a dramatic decrease in CN(-) desorption. An increase in the yields of OH(-) is also observed. The debromination yield of particular oligonucleotides diminishes in the following order: BrdU > BrdA > BrdG > BrdC. Based on these results, 5-bromo-2(')-deoxyuridine appears to be the best radiosensitizer among the studied bromonucleosides.
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Affiliation(s)
- Katarzyna Polska
- Department of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland
| | - Janusz Rak
- Department of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland
| | - Andrew D. Bass
- Research Group in the Radiation Sciences, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Pierre Cloutier
- Research Group in the Radiation Sciences, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Léon Sanche
- Research Group in the Radiation Sciences, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
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Chatgilialoglu C, Ferreri C, Terzidis MA. Purine 5′,8-cyclonucleoside lesions: chemistry and biology. Chem Soc Rev 2011; 40:1368-82. [DOI: 10.1039/c0cs00061b] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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25
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Polska K, Zielonka J, Chomicz L, Czerwicka M, Stepnowski P, Guzow K, Wiczk W, Smużyńska M, Kasprzykowski F, Żylicz-Stachula A, Skowron P, Rak J. Unexpected photoproduct generated via the acetone-sensitized photolysis of 5-bromo-2'-deoxyuridine in a water/isopropanol solution: experimental and computational studies. J Phys Chem B 2010; 114:16902-7. [PMID: 21117683 DOI: 10.1021/jp1071499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The acetone-sensitized photolysis of 5-bromo-2'-deoxyuridine (5-BrdU) in a water/isopropanol solution with 300 nm photons leads to the formation of 2'-deoxyuridine (dU) and a comparable amount of another photoproduct that has not been reported in the literature so far. The negative and positive mass spectra recorded for this species indicate that they originate from the molecular mass of 286 Da, which corresponds to an adduct of 2'-deoxyuridine and 2-propanol. Quantum chemical calculations carried out at the DFT and TDDFT levels reveal both the structure and the UV spectrum of that adduct. The latter computational characteristic matches well the experimental UV spectrum of the new photoproduct. Our findings indicate that the acetone-sensitized photolysis of 5-BrdU is more complicated than has hitherto been assumed. Nevertheless, since electron transfer is one of the pathways responsible for 5-BrdU decay, acetone-sensitized photolysis of the halogen derivatives of nucleobases could be a convenient tool for studying their radiosensitivity in aqueous solutions.
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Affiliation(s)
- Katarzyna Polska
- Department of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland
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26
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5′,8-Cyclopurine-2′-deoxynucleosides: Molecular structure and charge distribution – DFT study in gaseous and aqueous phase. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.theochem.2009.08.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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27
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8,5'-Cyclopurine-2'-deoxynucleosides in DNA: mechanisms of formation, measurement, repair and biological effects. DNA Repair (Amst) 2008; 7:1413-25. [PMID: 18603018 DOI: 10.1016/j.dnarep.2008.06.005] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 06/06/2008] [Accepted: 06/09/2008] [Indexed: 01/19/2023]
Abstract
8,5'-Cyclo-2'-deoxyadenosine (cdA) and 8,5'-cyclo-2'-deoxyguanosine (cdG) are among the major lesions formed in DNA by hydroxyl radical attack on 2'-deoxyadenosine and 2'-deoxyguanosine, respectively, followed by intramolecular cyclization between C5' and C8. Mechanisms of formation of these unique tandem lesions were elucidated. The 8,5'-cyclization causes an unusual puckering of the sugar moiety giving rise to significant distortion in the DNA double helix. Methodologies were developed for the measurement of these lesions in DNA by mass spectrometry coupled either with gas chromatography or high performance liquid chromatography. Both techniques allowed identification and quantification of both R- and S-diastereomers of cdA and cdG in DNA in vitro and in vivo. Because of the 8,5'-covalent bond between the sugar and base moieties in the same nucleoside, cdA and cdG are repaired by nucleotide excision repair rather than by base excision repair. Thus, these lesions may play a role in diseases with defective nucleotide excision repair. Their biological effects include blocking DNA polymerases, inhibition of gene expression, transcriptional mutagenesis among others. Accumulation of cdA and cdG was observed in tissues in vivo in connection to disease and environmental conditions, suggesting an important role for these lesions in disease processes including carcinogenesis and neuronal death.
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Boussicault F, Kaloudis P, Caminal C, Mulazzani QG, Chatgilialoglu C. The Fate of C5′ Radicals of Purine Nucleosides under Oxidative Conditions. J Am Chem Soc 2008; 130:8377-85. [DOI: 10.1021/ja800763j] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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30
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Kaloudis P, D'Angelantonio M, Guerra M, Gimisis T, Mulazzani QG, Chatgilialoglu C. One-Electron Reduction of 8-Bromo-2-aminoadenosine in the Aqueous Phase: Radiation Chemical and DFT Studies of the Mechanism. J Phys Chem B 2008; 112:5209-17. [DOI: 10.1021/jp800480f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Panagiotis Kaloudis
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Mila D'Angelantonio
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Maurizio Guerra
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Thanasis Gimisis
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Quinto G. Mulazzani
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
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Jimenez LB, Encinas S, Chatgilialoglu C, Miranda MA. Solar one-way photoisomerisation of 5',8-cyclo-2'-deoxyadenosine. Org Biomol Chem 2008; 6:1083-6. [PMID: 18327334 DOI: 10.1039/b718222h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Under sunlight irradiation (5'S)-5',8-cyclo-2'-deoxyadenosine 2 photoisomerises to the (5'R) isomer 1, which is the more easily repaired damage when these cyclopurine lesions are formed in DNA.
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Affiliation(s)
- Liliana B Jimenez
- Departamento de Química/Instituto de Tecnología Química UPV-CSIC, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain
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Oshima K. Highly Selective Synthetic Reactions by the Combined Use of Organometallic Reagents and Radical Species. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2008. [DOI: 10.1246/bcsj.81.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Chatgilialoglu C, Caminal C, Altieri A, Vougioukalakis GC, Mulazzani QG, Gimisis T, Guerra M. Tautomerism in the guanyl radical. J Am Chem Soc 2007; 128:13796-805. [PMID: 17044708 DOI: 10.1021/ja062636h] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Despite a few decades of intense study, a full description of tautomers of one-electron-oxidized guanine remains to be achieved. Here we show that two of these tautomers are produced by the protonation of an 8-haloguanine electron adduct. The rate constants for the reactions of hydrated electrons (e(aq)(-)) with a variety of 8-substituted guanine derivatives have been measured by a pulse radiolysis technique and correlated with both inductive and resonance components of the substituents. The fate of electron adducts was investigated by radiolytic methods coupled with product studies and addressed computationally by means of time-dependent DFT (TD-B3LYP/6-311G**//B1B95/6-31+G**) calculations. The reaction of e(aq)(-) with 8-haloguanosine or 8-halo-2'-deoxyguanosine produces the first observable transient species that decay unimolecularly (k = 1 x 10(5) s(-)(1) at 22 degrees C) to give the one-electron oxidized guanosine or 2'-deoxyguanosine. Theory suggests that the electron adducts of 8-bromoguanine derivatives protonated at C8 form a pi-complex, with the Br atom situated above the molecular plane, that is prompt to eject Br(-). The two short-lived intermediates, which show a substantial difference in their absorption spectra, are recognized to be the two purine tautomers (i.e., iminic 7 and aminic 3 forms). The spin density distributions of the two tautomers are quite different at the O6 and N10 positions, whereas they are very similar at the N3, C5, and C8 positions. The resonance structures of the two tautomers are discussed in some detail. B1B95/6-31+G calculations show also that the tautomerization from the iminic (7) to the aminic (3) arrangement is a water-assisted process.
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Hou R, Gu J, Xie Y, Yi X, Schaefer Iii HF. The 2'-deoxyadenosine-5'-phosphate anion, the analogous radical, and the different hydrogen-abstracted radical anions: molecular structures and effects on DNA damage. J Phys Chem B 2007; 109:22053-60. [PMID: 16853863 DOI: 10.1021/jp0524375] [Citation(s) in RCA: 13] [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
The 2'-deoxyadenosine-5'-phosphate (5'-dAMP) anion and its related radicals have been studied by reliably calibrated theoretical approaches. This study reveals important physical characteristics of 5'-dAMP radical related processes. One-electron oxidation of the 5'-dAMP anion is found on both the phosphoryl group and the adenine base with electron detachment energies close to that of phosphate. Partial removal of electron density from the adenine fragment leads to an extended pi system which includes the amine group of the adenine. Although the radical-centered carbon increases the extent of bonding with its adjacent atoms, it usually weakens the chemical bonds between the atoms at the alpha- and beta-positions. This tendency should be important in predicting the reactivity of the sugar-based radicals. The overall stability sequence of the H-abstracted 5'-dAMP anionic radicals is consistent with the analogous results for the H-abstracted neutral radicals of the adenosine nucleoside: aliphatic radicals > aromatic radicals. The negatively charged phosphoryl group attached to atom C(5)' of the ribose does not change this energetic sequence. All the H-abstraction produced 5'-dAMP radical anions are distonic radical anions. Studies have shown that the charge-radical-separating feature of the distonic radical anions is biologically relevant. This result should be important in understanding the reactive properties of these H-abstraction-produced anion radicals.
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Affiliation(s)
- Ruobing Hou
- Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602-2525, USA
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35
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Manetto A, Georganakis D, Leondiadis L, Gimisis T, Mayer P, Carell T, Chatgilialoglu C. Independent generation of C5'-nucleosidyl radicals in thymidine and 2'-deoxyguanosine. J Org Chem 2007; 72:3659-66. [PMID: 17425368 DOI: 10.1021/jo062518c] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of the C5' tert-butyl ketone of thymidine 1a and 2'-deoxyguanosine 2 is achieved by reaction of 5'-C-cyano derivatives with tert-butyl lithium followed by acid hydrolysis. The 5'R configuration is assigned by X-ray crystal structure determination of an opportunely protected derivative of 1a. The (5'S)-isomers of both nucleosides are not stable, and a complete decomposition occurs in the reaction medium. The photochemistry of 1a and 2 effectively produced the thymidin-5'-yl radical and the 2'-deoxyguanosin-5'-yl radical, respectively. In the thymidine system, the C5' radical is fully quenched in the presence of a physiological concentration of thiols. In the 2'-deoxyguanosine system, the C5' radical undergoes intramolecular attack onto the C8-N7 double bond of guanine leading ultimately to the 5',8-cyclo-2'-deoxyguanosine derivative. The cyclization of the 2'-deoxyguanosin-5'-yl radical occurs with a rate constant of ca. 1x10(6) s-1 and is highly stereoselective affording only the (5'S)-diastereomer.
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Affiliation(s)
- Antonio Manetto
- ISOF, Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy
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Russo M, Jimenez LB, Mulazzani QG, D'Angelantonio M, Guerra M, Miranda MA, Chatgilialoglu C. Chemical radiation studies of 8-bromo-2'-deoxyinosine and 8-bromoinosine in aqueous solutions. Chemistry 2007; 12:7684-93. [PMID: 16823787 DOI: 10.1002/chem.200600040] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The reactions of hydrated electrons (e(aq) (-)) with 8-bromo-2'-deoxyinosine (8) and 8-bromoinosine (12) have been investigated by radiolytic methods coupled with product studies and have been addressed computationally by means of BB1K-HMDFT calculations. Pulse radiolysis revealed that one-electron reductive cleavage of the C--Br bond gives the C8 radical 9 or 13 followed by a fast radical translocation to the sugar moiety. Selective generation of a C5' radical occurs in the 2'-deoxyribo derivative, whereas in the ribo analogue the reaction is partitioned between the C5' and C2' positions with similar rates. Both C5' radicals undergo cyclizations, 10-->11 and 14-->15, with rate constants of 1.4 x 10(5) and of 1.3 x 10(4) s(-1), respectively. The redox properties of radicals 10 and 11 have also been investigated. A synthetically useful photoreaction has also been developed as a one-pot procedure that allows the conversion of 8 to 5',8-cyclo-2'-deoxyinosine in a high yield and a diastereoisomeric ratio (5'R)/(5'S) of 4:1. The present results are compared with data previously obtained for 8-bromoadenine and 8-bromoguanine nucleosides. Theory suggests that the behavior of 8-bromopurine derivatives with respect to solvated electrons can be attributed to differences in the energy gap between the pi*- and sigma*-radical anions.
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Affiliation(s)
- Marialuisa Russo
- ISOF, Consiglio Nazionale delle Ricerche Via P. Gobetti 101, 40129 Bologna, Italy
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Navacchia ML, Chatgilialoglu C, Montevecchi PC. C5‘-Adenosinyl Radical Cyclization. A Stereochemical Investigation. J Org Chem 2006; 71:4445-52. [PMID: 16749773 DOI: 10.1021/jo060197z] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A variety of substituted 2'-deoxyadenosin-5'-yl radicals 3 were generated under different reaction conditions. Radicals 3 underwent intramolecular cyclization onto the C8-N7 double bond of the adenine moiety leading to aminyl radicals (5'S,8R)-4 and (5'R,8R)-4 and, eventually, to the corresponding cyclonucleosides 5 and 6. The effect of the solvent, the nature of the substituents, and the generation method of radicals 3 on the stereoselectivity of the C5'-radical cyclization have been considered. The observed increase of the (5'S)/(5'R) ratio by increasing the bulkiness of the R1 group is explained in terms of steric repulsion between R1 and the purine moiety which favors the C5'-endo conformation, whereas the effect of the water solvent in promoting the (5'R)-stereoselective cyclization is ascribed to intermolecular hydrogen bonding stabilizing the C5'-exo conformation.
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38
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Xerri B, Morell C, Grand A, Cadet J, Cimino P, Barone V. Radiation-induced formation of DNA intrastrand crosslinks between thymine and adenine bases: a theoretical approach. Org Biomol Chem 2006; 4:3986-92. [PMID: 17047880 DOI: 10.1039/b609134b] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The role of local geometric and stereo-electronic effects in tuning the radiation-induced formation of intrastrand crosslinks between adenine and thymine has been analyzed by a computational approach rooted in density functional theory. Our study points out that together with steric accessibility, stereo-electronic effects play a major role in determining the reaction mechanism and the observed predominance of the thymine-adenine lesion over the opposite sequence isomer.
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Affiliation(s)
- Bertrand Xerri
- Laboratoire Lésions des Acides Nucléiques, SCIB-UMR no. 3 (CEA/UJF) Département de Recherche Fondamentale sur la Matière Condensée, CEA/Grenoble, 17 Avenue des Martyrs, 38054, Grenoble cedex 9, France
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39
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Navacchia ML, Manetto A, Montevecchi PC, Chatgilialoglu C. Radical Cyclization Approach to Cyclonucleosides. European J Org Chem 2005. [DOI: 10.1002/ejoc.200500398] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Evangelista FA, Schaefer HF. Structures and Energetics of Adenosine Radicals: (2‘-dAdo − H)•. J Phys Chem A 2004. [DOI: 10.1021/jp040361r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Francesco A. Evangelista
- Scuola Normale Superiore di Pisa, 56126 Pisa, Italy, and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602-2525
| | - Henry F. Schaefer
- Scuola Normale Superiore di Pisa, 56126 Pisa, Italy, and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602-2525
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41
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Jimenez LB, Encinas S, Miranda MA, Navacchia ML, Chatgilialoglu C. The photochemistry of 8-bromo-2'-deoxyadenosine. A direct entry to cyclopurine lesions. Photochem Photobiol Sci 2004; 3:1042-6. [PMID: 15570393 DOI: 10.1039/b410939b] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The UV photolysis of 8-bromo-2'-deoxyadenosine has been investigated in different solvents and in the presence of additives like halide anions. Photolytic cleavage of the C-Br bond leads to formation of the C8 radical. In methanol, subsequent hydrogen abstraction from the solvent is the main radical reaction; however, in water or acetonitrile intramolecular hydrogen abstraction from the sugar moiety, to give the C5' radical, is the major path. This C5' radical undergoes a cyclization reaction on the adenine and gives the aminyl radical. A rate constant of 1.8 x 10(5) s(-1) has been measured by laser flash photolysis in CH(3)CN for this unimolecular process. Product studies from steady-state photolysis in acetonitrile have shown the conversion of 8-bromo-2'-deoxyadenosine to 5',8-cyclo-2'-deoxyadenosine in 65% yield and in a diastereoisomeric ratio (5' R):(5' S)= 1.7. Evidence supporting that the equilibrium Br*+ Br(-)[right left harpoons] Br(2)*(-) plays an important role in this synthetically useful radical cascade is obtained by regulating the relative concentrations of the two reactive oxidizing species.
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Affiliation(s)
- Liliana B Jimenez
- Departamento de Química/Instituto de Tecnologia Química UPV-CSIC, Universidad Politécnica de Valencia, Camino de Vera s/n, E-46022, Valencia, Spain
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42
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Lang P, Mayer A, Jung P, Tritsch D, Biellmann JF, Burger A. Radical cyclisation mediates the synthesis of a new base-ribose carbon bridged adenosine. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.03.176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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43
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Chatgilialoglu C, Guerra M, Mulazzani QG. Model studies of DNA C5' radicals. Selective generation and reactivity of 2'-deoxyadenosin-5'-yl radical. J Am Chem Soc 2003; 125:3839-48. [PMID: 12656617 DOI: 10.1021/ja029374d] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of hydrated electrons (e(aq)(-)) with 8-bromo-2'-deoxyadenosine has been investigated by radiolytic methods coupled with product studies and addressed computationally by means of DFT-B3LYP calculations. Pulse radiolysis revealed that this reaction was complete in approximately 0.3 mus, and, at this time, no significant absorption was detected. The spectrum of a transient developed in 20 mus has an absorbance in the range 300-500 nm (epsilon(max) congruent with 9600 M(-1) cm(-1) at 360 nm), and it was assigned to aromatic aminyl radical 3. Computed vertical transitions (TD-UB3LYP/6-311+G) are in good agreement with the experimental observations. Radical 3 is obtained by the following reaction sequence: one-electron reductive cleavage of the C-Br bond that gives the C8 radical, a fast radical translocation from the C8 to C5' position, and an intramolecular attack of the C5' radical at the C8,N7 double bond of the adenine moiety. The rate constant for the cyclization is 1.6 x 10(5) s(-1). On the basis of the theoretical findings, the cyclization step is highly stereospecific. The rate constants for the reactions of C5' and aminyl 3 radicals with different oxidants were determined by pulse radiolysis methods. The respective rate constants for the reaction of 2'-deoxyadenosin-5'-yl radical with dioxygen, Fe(CN)(6)(3)(-), and MV(2+) in water at ambient temperature are 1.9 x 10(9), 4.2 x 10(9), and 2.2 x 10(8) M(-1) s(-1). The value for the reaction of aminyl radical 3 with Fe(CN)(6)(3-) is 8.3 x 10(8) M(-1) s(-1), whereas the reaction with dioxygen is reversible. Tailored experiments allowed the reaction mechanism to be defined in some detail. A synthetically useful radical cascade process has also been developed that allows in a one-pot procedure the conversion of 8-bromo-2'-deoxyadenosine to 5',8-cyclo-2'-deoxyadenosine in a diastereoisomeric ratio (5'R):(5'S) = 6:1 and in high yield, by reaction with hydrated electrons in the presence of K(4)Fe(CN)(6).
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44
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Toure P, Villena F, Melikyan GG. Thymidine 3',5'-diphosphoric acid derived cations and radicals: ab initio study. Org Lett 2002; 4:3989-92. [PMID: 12423068 DOI: 10.1021/ol026231n] [Citation(s) in RCA: 13] [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 relative stabilities of thymidine-3',5'-diphosphoric acid (1) derived isomeric cations and radicals were calculated and key geometric parameters were thoroughly analyzed. The most probable sites of a hydride-ion (1', 2', 5-Me) and H-atom (4', 5', 5-Me) abstraction were identified, thus allowing prediction of the regioselectivity of potential damage to the deoxyribose ring and thymine moiety caused by carcinogenic agents of electrophilic and radical nature. [structure: see text]
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Affiliation(s)
- Pogban Toure
- Department of Chemistry, California State University-Northridge, Northridge, CA 91330, USA
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45
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Cadet J, Bellon S, Berger M, Bourdat AG, Douki T, Duarte V, Frelon S, Gasparutto D, Muller E, Ravanat JL, Sauvaigo S. Recent aspects of oxidative DNA damage: guanine lesions, measurement and substrate specificity of DNA repair glycosylases. Biol Chem 2002; 383:933-43. [PMID: 12222683 DOI: 10.1515/bc.2002.100] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This review discusses recent aspects of oxidation reactions of DNA and model compounds involving mostly OH radicals, one-electron transfer process and singlet oxygen (1O2). Emphasis is placed on the formation of double DNA lesions involving a purine base on one hand and either a pyrimidine base or a 2-deoxyribose moiety on the other hand. Structural and mechanistic information is also provided on secondary oxidation reactions of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), a major DNA marker of oxidative stress. Another major topic which is addressed here deals with recent developments in the measurement of oxidative base damage to cellular DNA. This has been mostly achieved using the accurate and highly specific HPLC method coupled with the tandem mass spectrometry detection technique. Interestingly, optimized conditions of DNA extraction and subsequent work-up allow the accurate measurement of 11 modified nucleosides and bases within cellular DNA upon exposure to oxidizing agents, including UVA and ionizing radiations. In addition, the modified comet assay, which involves the use of bacterial DNA N-glycosylases to reveal two main classes of oxidative base damage, is applicable to isolated cells and is particularly suitable when only small amounts of biological material are available. Finally, recently available data on the substrate specificity of DNA repair enzymes belonging to the base excision pathways are briefly reviewed.
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Affiliation(s)
- Jean Cadet
- Service de Chimie Inorganique et Biologique & UMR 5046, Département de Recherche Fondamentale sur la Matière Condensée, CEA/Grenoble, France
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Abstract
This short review focuses on the chemical events related to DNA damage induced by free radicals. Diffusible hydroxyl radicals (HO) are able to react with either the sugar units by hydrogen abstraction or with the base moieties by addition. Selectively generated carbon-centred radicals at C1', C4' and C5' in model nucleosides or oligonucleotides and their subsequent fate under aerobic or anoxic condition are discussed by rationalisation of the available kinetic data. Reaction paths for the formation of nucleobase modifications such as 8-oxoG and FapyG, amplification of base damage, and tandem lesions are also discussed. Some types of DNA damage may be poorly repaired leading to deleterious genetic changes with time.
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Affiliation(s)
- C Chatgilialoglu
- I.Co.C.E. A., Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy.
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47
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The Gomberg century: Free radicals 1900–2000. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2001. [DOI: 10.1016/s0065-3160(01)36002-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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