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Szorcsik A, Nagy L, Scopelliti M, Pellerito L, Sipos P. Characterization of complexes formed between [Me2Sn(IV)]2+ and carboxymethylcelluloses. Carbohydr Res 2006; 341:2083-9. [PMID: 16764843 DOI: 10.1016/j.carres.2006.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 05/04/2006] [Accepted: 05/16/2006] [Indexed: 11/22/2022]
Abstract
Complexes formed between carboxymethylcellulose (CMC) and the [Me(2)Sn(IV)]2+ cation have been prepared in the solid state and characterized by FTIR and Mössbauer spectroscopy. The complexes contained CMC with varying molar weight and degree of carboxylation, and the complexes were isolated both from acidic and from neutral solutions at varying metal-to-ligand ratios. The characteristic vibration bands of the ligands were identified from their pH-dependent FTIR spectra. In the organotin(IV) complexes obtained at pH approximately 2, the -COO- moieties were found to be coordinated in a monodentate manner, and the band characteristic of the protonated (unbound) -COO- group(s) was also identified. The broad -OH band can be interpreted as the sum of the contributions of the alcoholic -OH groups of the anhydroglucose units and the mixed organotin aqua complexes. In complexes obtained at pH approximately 7, the broad -OH band significantly sharpens, which is probably due to the metal-ion induced deprotonation and subsequent coordination of the alcoholic -OH groups. At the same time, -COO- groups are also involved in the coordination of the metal ions, resulting in a complicated network that forms through inter- and intramolecular bridges. Quadrupole splitting (/Delta(exp)/) values observed by Mössbauer spectroscopy revealed that the valence state of tin is four in all of the complexes. The /Delta(exp)/ values were compared with the calculated ones, obtained from the pqs theory. From these data, trigonal bipyramidal (Tbp) and octahedral (Oh) geometries have been suggested for the complexes obtained. It has also been concluded that the structure of the complexes prepared depends mainly on the pH of the solution, and it is relatively insensitive to the other parameters, like molar mass or degree of carboxylation of the ligand, or the metal-to-ligand ratio in the reaction mixture.
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Affiliation(s)
- A Szorcsik
- Bio-inorganic Chemistry Research Group of Hungarian Academy of Sciences, Department of Inorganic and Analytical Chemistry, University of Szeged, PO Box 440, H-6701 Szeged, Hungary
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Abstract
A summary is presented of the studies of our group on metal complexes of carbohydrates (aldoses, ketoses, mono-, di- and polysaccharides) and their derivatives (aldonic, alduronic acids, polyalcohols, amino sugars, amino acid sugar adducts, AMP, ATP, etc.). The results are reported of equilibrium, electrochemical, solution and solid-state structural studies of complexes of transition metals [Cu(II), Fe(III), Ni(II), Zn(II), Co(II), Ag(I), Mn in different oxidation states and organotin(IV)]. The structural parameters (coordination number, bond distance, and Debye-Waller factor) obtained by extended X-ray absorption fine structure spectroscopic (EXAFS) spectroscopy are discussed in detail. The general rules concerning the formation and structure of such complexes are emphasized.
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Affiliation(s)
- L Nagy
- Department of Inorganic and Analytical Chemistry, Szeged University, PO Box 440, H-6701, Szeged, Hungary.
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Jancsó A, Gajda T, Szorcsik A, Kiss T, Henry B, Vankó G, Rubini P. Potentiometric and spectroscopic studies on the dimethyltin(IV) complexes of 2-hydroxyhippuric acid. J Inorg Biochem 2001; 83:187-92. [PMID: 11237258 DOI: 10.1016/s0162-0134(00)00179-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Equilibrium and spectroscopic (1H, 13C NMR and 119Sn Mössbauer) studies in aqueous solution are reported for dimethyltin(IV) complexes of 2-hydroxyhippuric acid (Sal-Gly). Below pH 4, oxygen-coordinated complexes MLH and ML are formed. In the pH range 5-8.5, the species MLH(-1), predominates at any metal-to-ligand ratio. The ligand exchange of this species is slow on the NMR time scale, which allows its structural characterization by NMR spectroscopy: the coordination polyhedron around the tin atom is distorted trigonal bipyramidal, with tridentate [O-,N-,COO-] coordination of Sal-Gly, involving two equatorial methyl groups. The NMR results reveal that the main cause of the distortion of the polyhedron is the large CH3-Sn-CH3 angle of 136+/-4 degrees. The presented results supplement the data available on the dimethyltin(IV)-promoted amide deprotonation of peptides, and provide further arguments for the fundamental role of the carboxylate as an anchoring group in this process.
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Affiliation(s)
- A Jancsó
- Department of Inorganic and Analytical Chemistry, University of Szeged, Hungary
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Surdy P, Rubini P, Buzás N, Henry B, Pellerito L, Gajda T. Interaction of Dimethyltin(IV)2+ Cation with Gly-Gly, Gly-His, and Some Related Ligands. A New Case of a Metal Ion Able To Promote Peptide Nitrogen Deprotonation in Aqueous Solution. Inorg Chem 1999. [DOI: 10.1021/ic980398o] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Péter Surdy
- Department of Inorganic and Analytical Chemistry, A. József University, 6701 Szeged, P.O. Box 440, Hungary, Laboratoire de Chimie Physique Organique et Colloidale, UMR SRSMC CNRS No. 7565, Université Henri PoincaréNancy I, B.P. 239, F-54506 Vandoeuvre-lès-Nancy Cedex, France, Research Group on Biocoordination Chemistry of the Hungarian Academy of Sciences, A. József University, 6701 Szeged, P.O. Box 440, Hungary, and Department of Inorganic Chemistry, University of Palermo, Palermo, Italy
| | - Patrice Rubini
- Department of Inorganic and Analytical Chemistry, A. József University, 6701 Szeged, P.O. Box 440, Hungary, Laboratoire de Chimie Physique Organique et Colloidale, UMR SRSMC CNRS No. 7565, Université Henri PoincaréNancy I, B.P. 239, F-54506 Vandoeuvre-lès-Nancy Cedex, France, Research Group on Biocoordination Chemistry of the Hungarian Academy of Sciences, A. József University, 6701 Szeged, P.O. Box 440, Hungary, and Department of Inorganic Chemistry, University of Palermo, Palermo, Italy
| | - Norbert Buzás
- Department of Inorganic and Analytical Chemistry, A. József University, 6701 Szeged, P.O. Box 440, Hungary, Laboratoire de Chimie Physique Organique et Colloidale, UMR SRSMC CNRS No. 7565, Université Henri PoincaréNancy I, B.P. 239, F-54506 Vandoeuvre-lès-Nancy Cedex, France, Research Group on Biocoordination Chemistry of the Hungarian Academy of Sciences, A. József University, 6701 Szeged, P.O. Box 440, Hungary, and Department of Inorganic Chemistry, University of Palermo, Palermo, Italy
| | - Bernard Henry
- Department of Inorganic and Analytical Chemistry, A. József University, 6701 Szeged, P.O. Box 440, Hungary, Laboratoire de Chimie Physique Organique et Colloidale, UMR SRSMC CNRS No. 7565, Université Henri PoincaréNancy I, B.P. 239, F-54506 Vandoeuvre-lès-Nancy Cedex, France, Research Group on Biocoordination Chemistry of the Hungarian Academy of Sciences, A. József University, 6701 Szeged, P.O. Box 440, Hungary, and Department of Inorganic Chemistry, University of Palermo, Palermo, Italy
| | - Lorenzo Pellerito
- Department of Inorganic and Analytical Chemistry, A. József University, 6701 Szeged, P.O. Box 440, Hungary, Laboratoire de Chimie Physique Organique et Colloidale, UMR SRSMC CNRS No. 7565, Université Henri PoincaréNancy I, B.P. 239, F-54506 Vandoeuvre-lès-Nancy Cedex, France, Research Group on Biocoordination Chemistry of the Hungarian Academy of Sciences, A. József University, 6701 Szeged, P.O. Box 440, Hungary, and Department of Inorganic Chemistry, University of Palermo, Palermo, Italy
| | - Tamás Gajda
- Department of Inorganic and Analytical Chemistry, A. József University, 6701 Szeged, P.O. Box 440, Hungary, Laboratoire de Chimie Physique Organique et Colloidale, UMR SRSMC CNRS No. 7565, Université Henri PoincaréNancy I, B.P. 239, F-54506 Vandoeuvre-lès-Nancy Cedex, France, Research Group on Biocoordination Chemistry of the Hungarian Academy of Sciences, A. József University, 6701 Szeged, P.O. Box 440, Hungary, and Department of Inorganic Chemistry, University of Palermo, Palermo, Italy
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