title: Pyranoanthocyanin dimers: a new family of turquoise blue anthocyanin-derived pigments found in Port wine.
abstract: In the present work, several compounds bearing similar spectroscopic features were found to occur in aged Port wines and respective sediments (lees). The data obtained revealed two new families of compounds with unique spectroscopic characteristics, displaying a wavelength of the maximum absorption at high wavelength in the visible spectrum at approximately 730 and approximately 680 nm. The structure of these pigments was elucidated by liquid chromatography/diode array detector-mass spectrometry (LC/DAD-MS) and nuclear magnetic resonance (NMR), and their formation pathway in wines was established. Their structure is constituted by two pyranoanthocyanin moieties linked together through a methyne bridge. This new family of compounds displays an attractive and rare turquoise blue color at acidic conditions and has never been reported in the literature.
authors.affiliation: Centro de Investigacao em Quimica, Departamento de Quimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Oliveira
authors.forename: Joana
authors.initials: J
authors.lastname: Azevedo
authors.forename: Artur M S
authors.initials: AM
authors.lastname: Silva
authors.forename: Natércia
authors.initials: N
authors.lastname: Teixeira
authors.forename: Luis
authors.initials: L
authors.lastname: Cruz
authors.forename: Nuno
authors.initials: N
authors.lastname: Mateus
authors.forename: Victor
authors.initials: V
authors.lastname: de Freitas
mesh_terms: D000872:Anthocyanins / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D019281:Dimerization; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D014920:Wine / Q000032:analysis*
chemical_list: D000872:Anthocyanins