Self-association of a naphthalene-capped-β-cyclodextrin through cooperative strong hydrophobic interactions

NMR, circular dichroism and fluorescence techniques were used to study the structure in solution of a new β-cyclodextrin derivate in which naphthalene chromophore group is bridged to O(2) and O(3) secondary positions of the same glucopyranose unit through a bidentate hinge. The results point to the...

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Detalles Bibliográficos
Autores: González-Álvarez, M.José, Méndez Ardoy, Alejandro, Benito Hernández, Juan Manuel, García Fernández, José Manuel, Mendicuti, Francisco
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2011
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/156822
Acceso en línea:https://hdl.handle.net/11441/156822
https://doi.org/10.1016/j.jphotochem.2011.07.013
Access Level:acceso abierto
Palabra clave:Circular dichroism
Cyclodextrins
Fluorescence
Hydrophobic effect
Molecular modelling
Descripción
Sumario:NMR, circular dichroism and fluorescence techniques were used to study the structure in solution of a new β-cyclodextrin derivate in which naphthalene chromophore group is bridged to O(2) and O(3) secondary positions of the same glucopyranose unit through a bidentate hinge. The results point to the formation of a very stable dimer in aqueous solution which dissociates in non-polar solvents. Dimerization was enthalpy and entropy favoured. The hydrophobic character of the naphthyl moiety plays a very important role in the entropy change sign. Molecular mechanics as well as molecular dynamics calculations indicated that the most stable dimers are head-to-head oriented. For these dimer structures the naphthyl moieties, relatively shielded from the solvent, are sufficiently close to each other to couple their transition moments, but without forming excimers.