title: Intrinsically fluorescent glycoligands to study metal selectivity.
abstract: Glycoligands are a versatile family of ligands centered on a sugar platform and functionalized by Lewis bases. In this article, pentofuranoses were appended with the fluoroionophores 4-(pyridin-2'-yl)-1,2,3-triazol-1-yl and 4-(2',1',3'-benzothiadiazol-4'-yl)-1,2,3-triazol-1-yl using the "click-like" cycloaddition [2 + 3] of Huisgen catalyzed by copper(I). Their fluorescence properties were used to study metal cation complexation. A possible selective functionalization of furanoscaffolds allows the synthesis of "mixed" glycoligands with the successive insertion of these different fluoroionophores. The metal selectivity and the chelating behavior of these six resulting intrinsically fluorescent glycoligands were investigated. The change in the configuration at the carbon C3 of furanose did not influence either the metal selectivity or the binding constants. However, different selectivities and binding constants were found to depend on the nature of the fluoroionophore moieties. Overall, the triazolylbenzothiadiazolyl chelating group was shown to be less efficient than the triazolylpyridyl claw for complexation. Interestingly enough, the triazolylbenzothiadiazolyl claw, which fluoresces in the visible range, did not interfere in the binding and selectivity of the more efficient triazolylpyridyl claw. This study suggests that the triazolylbenzothiadiazolyl moiety could be used as an adequate fluorescent reporter to qualitatively monitor complexation of other moieties.
authors: Département de Chimie de l'ENS, Laboratoire des Biomolécules, UMR-CNRS 7203, Université Pierre et Marie Curie, 24 rue Lhomond, F-75231 Paris Cedex, France.
authors: Ludivine
authors: L
authors: Garcia
authors: Stéphane
authors: S
authors: Maisonneuve
authors: Jennifer Oudinet-Sin
authors: JO
authors: Marcu
authors: Régis
authors: R
authors: Guillot
authors: François
authors: F
authors: Lambert
authors: Juan
authors: J
authors: Xie
authors: Clotilde
authors: C
authors: Policar
mesh_terms: D001665:Binding Sites; D002241:Carbohydrates / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D058115:Lewis Bases / Q000138:chemical synthesis / Q000737:chemistry*; D008024:Ligands; D008670:Metals / Q000032:analysis*; D008958:Models, Molecular; D014466:Ultraviolet Rays
chemical_list: D002241:Carbohydrates; D005456:Fluorescent Dyes; D058115:Lewis Bases; D008024:Ligands; D008670:Metals