| Abstract
| - Three newly formed pigments were detected and isolated from a 2-year-old Port wine through TSKToyopearl HW-40(S) gel column chromatography and characterized by UV−visible spectrophotometry,NMR, and mass spectrometry (ESI/MS). 1H NMR and 13C NMR data for these pigments obtainedusing 1D and 2D NMR techniques (COSY, NOESY, gHSQC, and gHMBC) are reported for the firsttime. The structure of the pigments was found to correspond to the vinyl cycloadducts of malvidin3-coumaroylglucoside bearing either a procyanidin dimer or a flavanol monomer ((+)-catechin or(−)-epicatechin). Additionally, conformational analysis was performed for one of these newly formedpigment using computer-assisted model building and molecular mechanics. A chemical nomenclatureis proposed to unambiguously name this new family of anthocyanin-derived pigments. Keywords: Red wine; flavanol; aging; pigments; anthocyanins; isomers; NMR; mass spectrometry
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