title: Gas-phase interactions of organotin compounds with cysteine.
abstract: The gas-phase interactions of cysteine with di-organotin and tri-organotin compounds have been studied by mass spectrometry experiments and quantum calculations. Positive-ion electrospray spectra show that the interaction of di- and tri-organotins with cysteine results in the formation of [(R)2Sn(Cys-H)]+and [(R)3Sn(Cys)]+ions, respectively. MS/MS spectra of [(R)2Sn(Cys-H)]+complexes are characterized by numerous fragmentation processes, notably associated with elimination of NH3and (C,H2,O2). Several dissociation routes are characteristic of each given organic species. Upon collision, both the [(R)3Sn(Gly)]+and [(R)3Sn(Cys)]+complexes are associated with elimination of the intact amino acid, leading to the formation of [(R)3Sn]+cation. But for the latter complex, two additional fragmentation processes are observed, associated with the elimination of NH3and C3H4O2S. Calculations indicate that the interaction between organotins and cysteine is predominantly electrostatic but also exhibits a considerable covalent character, which is slightly more pronounced in tri-organotin complexes. A preferred bidentate interaction of the type -η2-S-NH2, with sulfur and the amino group, is observed. As for the [(R)3Sn(Cys)]+complexes, their stability is due to the combination of the hydrogen bond taking place between the amino group and the sulfur lone pair and the interaction between the carboxylic oxygen atom and the metal. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Laboratoire de Chimie Analytique et Electrochimie Campus Universitaire, Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092, Tunis, Tunisia. latifa.latrous@ipeiem.rnu.tn.
authors.forename: Latifa
authors.initials: L
authors.lastname: Latrous
authors.affiliation: Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry Val d'Essonne, Bâtiment Maupertuis-Boulevard François Mitterrand, 91025, Evry, France.|CNRS-UMR 8587, Evry, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Salpin
authors.affiliation: Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry Val d'Essonne, Bâtiment Maupertuis-Boulevard François Mitterrand, 91025, Evry, France.|CNRS-UMR 8587, Evry, France.
authors.forename: Violette
authors.initials: V
authors.lastname: Haldys
authors.affiliation: Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry Val d'Essonne, Bâtiment Maupertuis-Boulevard François Mitterrand, 91025, Evry, France.|CNRS-UMR 8587, Evry, France.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Léon
authors.affiliation: Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry Val d'Essonne, Bâtiment Maupertuis-Boulevard François Mitterrand, 91025, Evry, France.|CNRS-UMR 8587, Evry, France.
authors.forename: Catarina
authors.initials: C
authors.lastname: Correia
authors.affiliation: Departamento de Química, Ciencias, M-13, Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC Cantoblanco, 28049, Madrid, Spain.
authors.forename: Al Mokhtar
authors.initials: AM
authors.lastname: Lamsabhi
mesh_terms: D003545:Cysteine / Q000737:chemistry*; D008956:Models, Chemical; D009947:Organotin Compounds / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D055672:Static Electricity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014835:Volatilization
chemical_list: D009947:Organotin Compounds; D010446:Peptide Fragments; D003545:Cysteine
keywords: ab initio calculations; cysteine; gas-phase reaction; mass spectrometry; organotins