151
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Tarábek P, Bonifačić M, Naumov S, Beckert D. Time Resolved FT EPR Identification of (E) and (Z) Conformational Isomers of Glycyl Radicals Formed upon Photoinduced Oxidation of Glycine Esters in Aqueous Solutions. J Phys Chem A 2004. [DOI: 10.1021/jp0367070] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Peter Tarábek
- Interdisciplinary Research Group “Time-Resolved Spectroscopy”, Faculty of Chemistry and Mineralogy, University of Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany, Department of Physical Chemistry, Ruder Bošković Institute, Bijenička c. 54, HR-10 000 Zagreb, Croatia, and Leibniz-Institute of Surface Modification, Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany
| | - Marija Bonifačić
- Interdisciplinary Research Group “Time-Resolved Spectroscopy”, Faculty of Chemistry and Mineralogy, University of Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany, Department of Physical Chemistry, Ruder Bošković Institute, Bijenička c. 54, HR-10 000 Zagreb, Croatia, and Leibniz-Institute of Surface Modification, Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany
| | - Sergei Naumov
- Interdisciplinary Research Group “Time-Resolved Spectroscopy”, Faculty of Chemistry and Mineralogy, University of Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany, Department of Physical Chemistry, Ruder Bošković Institute, Bijenička c. 54, HR-10 000 Zagreb, Croatia, and Leibniz-Institute of Surface Modification, Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany
| | - Dieter Beckert
- Interdisciplinary Research Group “Time-Resolved Spectroscopy”, Faculty of Chemistry and Mineralogy, University of Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany, Department of Physical Chemistry, Ruder Bošković Institute, Bijenička c. 54, HR-10 000 Zagreb, Croatia, and Leibniz-Institute of Surface Modification, Leipzig, Permoserstrasse 15, Leipzig, D-04318 Germany
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152
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Croft AK, Easton CJ, Kociuba K, Radom L. Strategic use of amino acid N-substituents to limit α-carbon-centered radical formation and consequent loss of stereochemical integrity. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0957-4166(03)00542-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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153
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Efficient synthesis of β-halogeno protected l-alanines and their β-phosphonium derivatives. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0957-4166(03)00484-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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154
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Kotha S, Lahiri K. Application of the Suzuki-Miyaura cross-coupling reaction for the modification of phenylalanine peptides. Biopolymers 2003; 69:517-28. [PMID: 12879497 DOI: 10.1002/bip.10420] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have demonstrated an exceptionally simple and a useful methodology for modification of unusual phenylalanine peptides by adapting the building block approach using the Suzuki-Miyaura cross-coupling reaction as a key step. This strategy gave a good overall yield of various modified tri- and pentapeptides that may be useful to prepare various biologically active peptides in a short period of time.
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Affiliation(s)
- Sambasivarao Kotha
- Department of Chemistry, Indian Institute of Technology-Bombay, Mumbai, 400 076, India.
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155
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Easton CJ, Edwards AJ, McNabb SB, Merrett MC, O'Connell JL, Simpson GW, Simpson JS, Willis AC. Allylic halogenation of unsaturated amino acids. Org Biomol Chem 2003; 1:2492-8. [PMID: 12956066 DOI: 10.1039/b303719c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A range of dehydro amino acid derivatives has been prepared and subjected to halogenation using either molecular bromine or chlorine, or NBS. Allylic halogenation of the unsaturated amino acid side chains occurs through radical bromination with NBS. The procedure is complementary to treatment with chlorine, which also affords allyl halides. This latter and unusual reaction is shown through a deuterium labelling study to proceed via an ionic mechanism. The choice of NBS or chlorine for allyl halide synthesis is shown to depend on the potential to avoid competing reactions, such as halolactonization of leucine derivatives with chlorine, and hydrogen abstraction and bromine incorporation at multiple sites on treatment of isoleucine derivatives with NBS. The synthetic utility of the allyl halides prepared in this study is indicated through the synthesis of a cyclopropyl amino acid derivative and the extension of the carbon skeleton of an amino acid side chain.
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Affiliation(s)
- Christopher J Easton
- Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia.
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156
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Abstract
Proteins comprise approximately 68% of the dry weight of cells and tissues and are therefore potentially major targets for oxidative damage. Two major types of processes can occur during the exposure of proteins to UV or visible light. The first of these involves direct photo-oxidation arising from the absorption of UV radiation by the protein, or bound chromophore groups, thereby generating excited states (singlet or triplets) or radicals via photo-ionisation. The second major process involves indirect oxidation of the protein via the formation and subsequent reactions of singlet oxygen generated by the transfer of energy to ground state (triplet) molecular oxygen by either protein-bound, or other, chromophores. Singlet oxygen can also be generated by a range of other enzymatic and non-enzymatic reactions including processes mediated by heme proteins, lipoxygenases, and activated leukocytes, as well as radical termination reactions. This paper reviews the data available on singlet oxygen-mediated protein oxidation and concentrates primarily on the mechanisms by which this excited state species brings about changes to both the side-chains and backbone of amino acids, peptides, and proteins. Recent work on the identification of reactive peroxide intermediates formed on Tyr, His, and Trp residues is discussed. These peroxides may be important propagating species in protein oxidation as they can initiate further oxidation via both radical and non-radical reactions. Such processes can result in the transmittal of damage to other biological targets, and may play a significant role in bystander damage, or dark reactions, in systems where proteins are subjected to oxidation.
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Affiliation(s)
- Michael J Davies
- The Heart Research Institute, 145 Missenden Road, Camperdown, Sydney NSW 2050, Australia.
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157
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Croft AK, Easton CJ, Radom L. Design of radical-resistant amino acid residues: a combined theoretical and experimental investigation. J Am Chem Soc 2003; 125:4119-24. [PMID: 12670233 DOI: 10.1021/ja029674v] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ab initio calculations have been used to design radical-resistant amino acid residues. Optimized structures of free and protected amino acids and their corresponding alpha-carbon-centered radicals were determined with B3-LYP/6-31G(d). Single-point RMP2/6-31G(d) calculations on these structures were then used to obtain radical stabilization energies, to examine the effect of steric repulsion between the side chains and amide carbonyl groups on the stability of alpha-carbon-centered peptide radicals. Relative to glycine, the destabilization for alanine and valine residues was found to be approximately 9 and 18 kJ mol(-1), respectively, which correlates with the reactivity of analogous amino acid residues in peptides toward hydrogen atom abstraction in conventional free radical reactions. To design amino acid residues that would resist radical reactions, strategies by which the steric effects could be magnified were considered. This resulted in the identification of tert-leucine and 3,3,3-trifluoroalanine as suitable molecules. With these amino acid residues, the destabilization of the alpha-carbon-centered radicals relative to that of glycine is increased substantially to approximately 36 and 41 kJ mol(-1), respectively. The theoretical predictions have been supported by experimental observations: a tert-leucine derivative was shown to be very slow to react with N-bromosuccinimide, while the corresponding trifluoroalanine derivative was found to be inert.
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Affiliation(s)
- Anna K Croft
- Contribution from the Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
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158
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Koerber C, Fensterbank L, Malacria M. Reactivity of NBS towards N-allyl glycinyl derivatives. CR CHIM 2003. [DOI: 10.1016/s1631-0748(03)00068-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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159
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Andrukiewicz R, Loska R, Prisyahnyuk V, Staliński K. Application of peptidyl radicals into a new radical cascade leading to unsaturated gamma-lactams. J Org Chem 2003; 68:1552-4. [PMID: 12585901 DOI: 10.1021/jo020602w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Radical cyclization of dipeptides 1a-h proceeds smoothly to give five- and seven-membered rings in good to moderate total yields using Stork's catalytic tin hydride method. A radical is generated on a protecting group and translocated to the peptide moiety. Following a cyclization reaction, the vinyl radical can abstract hydrogen from a benzyl group on an amine, which results in elimination of the protected amine group. Encouraging results have notably been obtained with amino acids other than glycine.
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Affiliation(s)
- Robert Andrukiewicz
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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160
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Suero R, Gorgojo JM, Aurrecoechea JM. Synthesis of 3-aminopyrrolidines by cyclization of neutral C-centered α-aminoalkyl radicals. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00621-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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161
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Simon S, Sodupe M, Bertran J. Isomerization versus Fragmentation of Glycine Radical Cation in Gas Phase. J Phys Chem A 2002. [DOI: 10.1021/jp020011+] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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162
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Headlam HA, Davies MJ. Beta-scission of side-chain alkoxyl radicals on peptides and proteins results in the loss of side-chains as aldehydes and ketones. Free Radic Biol Med 2002; 32:1171-84. [PMID: 12031901 DOI: 10.1016/s0891-5849(02)00814-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Exposure of proteins to radicals in the presence of O(2) results in side-chain oxidation and backbone fragmentation; the interrelationship between these processes is not fully understood. Recently, initial attack on Ala side-chains was shown to give alpha-carbon radicals (and hence backbone cleavage) and formaldehyde, via the formation and subsequent beta-scission, of C-3 alkoxyl radicals. We now show that this side-chain to backbone damage transfer, is a general mechanism for aliphatic side-chains. Oxidation of Val, Leu, and Asp residues by HO(*)/O(2) results in the release of a family of carbonyls (including formaldehyde, acetone, isobutyraldehyde, and glyoxylic acid) via the formation, and subsequent beta-scission of alkoxyl radicals. The concentration of these products increases with the HO(*) flux. The release of multiple carbonyls confirms the occurrence of oxidation at C-3 and C-4 for Val, and these sites, plus C-5, for Leu. The detection of glyoxylic acid and CO(2)(-*) from Asp demonstrates the occurrence of competing beta-scission processes for the Asp C-3 alkoxyl radical. The yield of hydroperoxides and released carbonyls account for 10-145% of the initial HO(*). The greater than 100% yields confirm the occurrence of chain reactions in peptide/protein oxidation, with more than one residue being damaged per initiating radical.
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Affiliation(s)
- Henrietta A Headlam
- The Free Radical Group, Heart Research Institute, Camperdown, Sydney, Australia
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163
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Jacobsen MF, Turks M, Hazell R, Skrydstrup T. SmI(2)-mediated cyclizations of derivatized beta-lactams for the highly diastereoselective construction of functionalized prolines. J Org Chem 2002; 67:2411-7. [PMID: 11950281 DOI: 10.1021/jo0104983] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of C4-keto-functionalized 1-[(benzoyloxy)(ethoxycarbonyl)methyl]-2-azetidinones were prepared and studied for their tendency to undergo a Reformatsky-type cyclization to fused bicyclic or tricyclic beta-lactams with the single-electron reducing agent samarium diiodide. Whereas the azetidinone 21a underwent reductive cyclization, affording the potent antibiotic sanfetrinem's tricyclic [4.5.6] core structure as the major component, all other examples tested resulted in cyclization followed by an N to O acyl migration involving cleavage of the beta-lactam ring as the favored pathway. Highly functionalized proline derivatives were therefore accessed as single diastereomers through the reductive cyclization of benzoates 21b, 22, 23a,b, 24b, and 25-28. Pertinent for the success of these cyclizations was the addition of 1 equiv of tert-butyl alcohol, allowing for the protonation of the basic amide derivative obtained after the acyl migration step. The diastereoselectivities of these reactions deviate from those of similar cyclizations involving the corresponding lithium enolate. This divergence could be rationalized by the coordination of the metal ion of the samarium(III) enolate intermediate to the beta-lactam amide functionality in the cyclization step, which may not be possible for lithium enolates.
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Affiliation(s)
- Mikkel F Jacobsen
- Department of Chemistry, University of Aarhus, Langelandsgade 140, 8000 Aarhus C, Denmark
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164
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Yim AM, Vidal Y, Viallefont P, Martinez J. Diastereoselective radical addition to dehydroalanine derivatives of pantolactone. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0957-4166(02)00135-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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165
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Davies MJ, Truscott RJ. Photo-oxidation of proteins and its role in cataractogenesis. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2001; 63:114-25. [PMID: 11684458 DOI: 10.1016/s1011-1344(01)00208-1] [Citation(s) in RCA: 320] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Proteins comprise approximately 68% of the dry weight of cells and tissues and are therefore potentially major targets for photo-oxidation. Two major types of processes can occur with proteins. The first of these involves direct photo-oxidation arising from the absorption of UV radiation by the protein, or bound chromophore groups, thereby generating excited states (singlet or triplets) or radicals via photo-ionisation. The second major process involves indirect oxidation of the protein via the formation and subsequent reactions of singlet oxygen generated by the transfer of energy to ground state (triplet) molecular oxygen by either protein-bound, or other, chromophores. The basic principles behind these mechanisms of photo-oxidation of amino acids, peptides and proteins and the potential selectivity of damage are discussed. Emphasis is placed primarily on the intermediates that are generated on amino acids and proteins, and the subsequent reactions of these species, and not the identity or chemistry of the sensitizer itself, unless the sensitizing group is itself intrinsic to the protein. A particular system is then discussed--the cataractous lens--where UV photo-oxidation may play a role in the aetiology of the disease, and tryptophan-derived metabolites act as UV filters.
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Affiliation(s)
- M J Davies
- The Heart Research Institute, 145 Missenden Road Camperdown, Sydney, NSW 2050, Australia.
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166
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Cheng H, Gan L, Shi Y, Wei X. A novel[2 + 3]cycloaddition reaction: singlet oxygen mediated formation of 1,3-dipole from iminodiacetic acid dimethyl ester and its addition to maleimides. J Org Chem 2001; 66:6369-74. [PMID: 11559188 DOI: 10.1021/jo015749m] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sensitized photolysis of iminodiacetic acid methyl ester and maleimides follows a [2 + 3] cycloaddition pathway yielding pyrrolidine derivatives. This is similar to the photochemical reaction between C(60) and amines. A series of pyrrolidine derivatives are prepared by the method including multipyrrolidines from bis- and tris-maleimide starting materials. The yields range from 13% to 85%. The reaction is highly stereoselective. All the isolated products have the 1,3-dimethoxycarbonyl groups in the cis configuration. Various sensitizers may be used with slightly different yields. A plausible mechanism is proposed that involves the singlet oxygen abstraction of two alpha hydrogen atoms from the iminodiacetate and formation of a 1,3-dipole with a structure similar to the classical thermally generated 1,3-dipole.
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Affiliation(s)
- H Cheng
- State Key Laboratory of Rare Earth Materials Chemistry and Applications, Department of Chemistry, Peking University, Beijing 100871, China
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167
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Knowles HS, Hunt K, Parsons AF. A photochemical approach to phenylalanines and related compounds by alkylation of glycine. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00783-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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168
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Jones RC, Berthelot DJ, Iley JN. Synthesis by conjugate radical addition of new heterocyclic amino acids with nucleobase side chains. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00546-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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169
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The Barton radical decarboxylation on solid phase. A versatile synthesis of peptides containing modified amino acids. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(01)00496-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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170
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Hawkins CL, Davies MJ. Generation and propagation of radical reactions on proteins. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1504:196-219. [PMID: 11245785 DOI: 10.1016/s0005-2728(00)00252-8] [Citation(s) in RCA: 502] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The oxidation of proteins by free radicals is thought to play a major role in many oxidative processes within cells and is implicated in a number of human diseases as well as ageing. This review summarises information on the formation of radicals on peptides and proteins and how radical damage may be propagated and transferred within protein structures. The emphasis of this article is primarily on the deleterious actions of radicals generated on proteins, and their mechanisms of action, rather than on enzymatic systems where radicals are deliberately formed as transient intermediates. The final section of this review examines the control of protein oxidation and how such damage might be limited by antioxidants.
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Affiliation(s)
- C L Hawkins
- Heart Research Institute, 145 Missenden Road, Camperdown, 2050, Sydney, NSW, Australia
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171
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Sibi MP, Asano Y, Sausker JB. Enantioselective Hydrogen Atom Transfer Reactions: Synthesis ofN-Acyl-α-Amino Acid Esters. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010401)113:7<1333::aid-ange1333>3.0.co;2-g] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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172
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Sibi MP, Asano Y, Sausker JB. Enantioselective Hydrogen Atom Transfer Reactions: Synthesis of N-Acyl-alpha-Amino Acid Esters This work was supported by the National Institutes of Health (NIH-GM-54656). Angew Chem Int Ed Engl 2001; 40:1293-1296. [PMID: 11301456 DOI: 10.1002/1521-3773(20010401)40:7<1293::aid-anie1293>3.0.co;2-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Mukund P. Sibi
- Department of Chemistry North Dakota State University Fargo, ND 58105-5516 (USA)
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173
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Belen’kii L, Kruchkovskaya N, Gramenitskaya V. The Literature of Heterocyclic Chemistry, Part VII: 1997–1999. ADVANCES IN HETEROCYCLIC CHEMISTRY 2001. [DOI: 10.1016/s0065-2725(01)79024-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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174
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Adamo C, Cossi M, Rega N, Barone V. New computational strategies for the quantum mechanical study of biological systems in condensed phases. THEORETICAL AND COMPUTATIONAL CHEMISTRY 2001. [DOI: 10.1016/s1380-7323(01)80013-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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175
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Photo-oxidation of proteins and its consequences. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s1568-461x(01)80047-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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176
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Lallemand MC, François D, Laimer I, Kunesch N, Husson HP. SYNTHESIS AND REACTIVITY OF ENDOCYCLIC α-CYANOENAMINES IN THE PHENYLOXAZOLOPIPERIDINE SERIES. SYNTHETIC COMMUN 2001. [DOI: 10.1081/scc-100106032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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177
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Ricci M, Peter Blakskjær, and, Skrydstrup T. Selective Side Chain Introduction onto Small Peptides Mediated by Samarium Diiodide: A Potential Route to Peptide Libraries. J Am Chem Soc 2000. [DOI: 10.1021/ja0024800] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marina Ricci
- Contribution from the Department of Chemistry, University of Aarhus, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Peter Blakskjær, and
- Contribution from the Department of Chemistry, University of Aarhus, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Troels Skrydstrup
- Contribution from the Department of Chemistry, University of Aarhus, Langelandsgade 140, 8000 Aarhus C, Denmark
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178
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Headlam HA, Mortimer A, Easton CJ, Davies MJ. beta-Scission of C-3 (beta-carbon) alkoxyl radicals on peptides and proteins: a novel pathway which results in the formation of alpha-carbon radicals and the loss of amino acid side chains. Chem Res Toxicol 2000; 13:1087-95. [PMID: 11087430 DOI: 10.1021/tx0001171] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Exposure of proteins to radicals in the presence of O(2) brings about multiple changes in the target molecules. These alterations include oxidation of side chains, fragmentation, cross-linking, changes in hydrophobicity and conformation, altered susceptibility to proteolytic enzymes, and formation of new reactive groups, including hydroperoxides. These processes can result in the loss of structural or enzymatic activity. Backbone fragmentation is known to occur via a number of mechanisms, most of which involve hydrogen abstraction from the alpha-carbon site on the backbone. In this study, we demonstrate that initial attack at a side chain site, the beta-position (C-3), can give rise to formation of alpha-carbon radicals, and hence backbone cleavage, via the formation and subsequent beta-scission of C-3 alkoxyl radicals. This beta-scission reaction is rapid (k estimated to be >10(7) s(-)(1)) even with primary alkoxyl radicals derived from Ala residues, and occurs when the alkoxyl radicals are generated from a variety of precursors, including hydroperoxides and nitrate esters. These reactions release the former side chain as a reactive aldehyde or ketone; thus, Ala peptides release high yields of methanal (formaldehyde). This product has been quantified with a number of oxidized peptides and proteins, and can account for up to 64% of the initial attacking radicals with some Ala peptides. When quantified together with the hydroperoxide precursors, these species account for up to 80% of the initial radicals, confirming that this is a major process. Methanal causes cell toxicity and DNA damage and is an animal carcinogen and a genotoxic agent in human cells. Thus, the formation and subsequent reaction of alkoxyl radicals formed at the C-3 position on aliphatic amino acid side chains on peptides and proteins can give rise to both backbone fragmentation and the release of further reactive species which can cause cell toxicity and mutagenicity.
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Affiliation(s)
- H A Headlam
- The EPR Group, The Heart Research Institute, 145 Missenden Road, Camperdown, Sydney, NSW 2050, Australia
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179
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Knowles HS, Hunt K, Parsons AF. Photochemical alkylation of glycine leading to phenylalanines. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)01175-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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180
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Ban F, Gauld JW, Boyd RJ. A Density Functional Theory Study of the Radiation Products of Glycine. J Phys Chem A 2000. [DOI: 10.1021/jp993844h] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fuqiang Ban
- Department of Chemistry, Dalhousie University, Halifax, NS, Canada B3H 4J3
| | - James W. Gauld
- Department of Chemistry, Dalhousie University, Halifax, NS, Canada B3H 4J3
| | - Russell J. Boyd
- Department of Chemistry, Dalhousie University, Halifax, NS, Canada B3H 4J3
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181
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Abstract
[reaction: see text] Fullerene catalyzes the cycloaddition of dimethyliminodiacetate to maleimides under photolysis to form 2,5-dimethoxycarbonylpyrrolidine derivatives.
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182
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183
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Caballero E, Avendaño C, Menéndez J. Steric and stereochemical effects on the free-radical bromination of tetracyclic and hexacyclic fragments of the MDR inhibitor N-acetylardeemin. Tetrahedron 1999. [DOI: 10.1016/s0040-4020(99)00886-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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184
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Abstract
Various methodologies published in the literature dealing with alpha-amino carboxylic acid asymmetric synthesis are presented in a digest form. In each case, only some recent or most typical works are mentioned.
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Affiliation(s)
- M Calmes
- Laboratoire des Aminoacides, Peptides et Protéines, UMR-CNRS 5810, Universités Montpellier I, France
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185
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Wise KE, Pate JB, Wheeler RA. Phenoxyl, (Methylthio)phenoxyl, and (Methylthio)cresyl Radical Models for the Structures, Vibrations, and Spin Properties of the Cysteine-Linked Tyrosyl Radical in Galactose Oxidase. J Phys Chem B 1999. [DOI: 10.1021/jp990580q] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kristopher E. Wise
- Department of Chemistry and Biochemistry, 620 Parrington Oval, Room 208, University of Oklahoma, Norman, Oklahoma 73019
| | - J. Brett Pate
- Department of Chemistry and Biochemistry, 620 Parrington Oval, Room 208, University of Oklahoma, Norman, Oklahoma 73019
| | - Ralph A. Wheeler
- Department of Chemistry and Biochemistry, 620 Parrington Oval, Room 208, University of Oklahoma, Norman, Oklahoma 73019
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186
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Easton CJ, Peters SC. α-Benzoyloxy- and α-Methoxy-Substituted Glycine Derivatives as Atypical Substrates for Free-Radical Reactions With Stannanes. PHOSPHORUS SULFUR 1999. [DOI: 10.1080/10426509908546381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Christopher J. Easton
- a Research School of Chemistry, Australian National University , Canberra ACT 0200, Australia
- b Research School of Chemistry, Australian National University , Canberra ACT 0200, Australia
| | - Steven C. Peters
- a Research School of Chemistry, Australian National University , Canberra ACT 0200, Australia
- b Research School of Chemistry, Australian National University , Canberra ACT 0200, Australia
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187
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Giraud L, Renaud P. Protecting/Radical Translocating Chiral Auxiliaries: A New Concept in Radical-Mediated Asymmetric Synthesis. J Org Chem 1998. [DOI: 10.1021/jo981836b] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luc Giraud
- Université de Fribourg, Institut de Chimie Organique, Pérolles, CH-1700 Fribourg, Switzerland
| | - Philippe Renaud
- Université de Fribourg, Institut de Chimie Organique, Pérolles, CH-1700 Fribourg, Switzerland
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188
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Generation of glycinyl radicals via a 1,5-hydrogen atom transfer reaction. Applications to γ-lactam formation. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)01042-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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189
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Gan L, Jiang J, Zhang W, Su Y, Shi Y, Huang C, Pan J, Lü M, Wu Y. Synthesis of Pyrrolidine Ring-Fused Fullerene Multicarboxylates by Photoreaction. J Org Chem 1998. [DOI: 10.1021/jo971990i] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Liangbing Gan
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Jianfeng Jiang
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Wen Zhang
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Yang Su
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Yaru Shi
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Chunhui Huang
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Jinqi Pan
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Mujian Lü
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
| | - Yi Wu
- State Key Laboratory of Rare Earth Material Chemistry and Applications, Peking University, Beijing 100871, China, Center of Instrumental Analysis, Department of Chemistry, Peking University, Beijing 100871, China, and Beijing Institute of Microchemistry, Beijing 100091, China
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190
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Abstraction of deuterium from dideuteroglycine by aryl radical: A model for 1, 4-benzene diradical reactions with proteins. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)00791-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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191
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Rega N, Cossi M, Barone V. Structure and Magnetic Properties of Glycine Radical in Aqueous Solution at Different pH Values. J Am Chem Soc 1998. [DOI: 10.1021/ja974232i] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nadia Rega
- Contribution from the Dipartimento di Chimica, Università Federico II via Mezzocannone 4, I-80134 Napoli, Italy
| | - Maurizio Cossi
- Contribution from the Dipartimento di Chimica, Università Federico II via Mezzocannone 4, I-80134 Napoli, Italy
| | - Vincenzo Barone
- Contribution from the Dipartimento di Chimica, Università Federico II via Mezzocannone 4, I-80134 Napoli, Italy
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192
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Richard Baker S, Parsons AF, Wilson M. Radical reactions leading to substituted pyroglutamates. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)00254-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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193
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Horneman AM, Lundt I. Highly Functionalized Cyclopentanes by Radical Cyclization of Unsaturated Bromolactones. 2. A Facile Synthesis of the First Carbaaldohexofuranoses and Their Conversion to Carbapentofuranoses. J Org Chem 1998. [DOI: 10.1021/jo971928l] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anne Marie Horneman
- Department of Organic Chemistry, Technical University of Denmark, Building 201, DK-2800 Lyngby, Denmark
| | - Inge Lundt
- Department of Organic Chemistry, Technical University of Denmark, Building 201, DK-2800 Lyngby, Denmark
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194
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Stojanovic A, Renaud P. N,Se-Acetals: Preparation and use in diastereoselective radical reactions. Helv Chim Acta 1998. [DOI: 10.1002/hlca.19980810216] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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195
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Hanessian S, Yang H. Design of a novel secondary structure scaffolding device: Induction of a reverse turn in tetrapeptides by incorporating a β-amino acid and stereocontrolled free radical α-substitution reactions in peptide motifs. Tetrahedron Lett 1997. [DOI: 10.1016/s0040-4039(97)00612-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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196
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J. Easton C, B. Kelly J, M. Ward C. Regioselective Hydrogen-atom Transfer from Triglycine†. JOURNAL OF CHEMICAL RESEARCH 1997. [DOI: 10.1039/a703000b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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