Isolation and structural characterization of new acylated anthocyanin-vinyl-flavanol pigments occurring in aging red wines.

摘要: Three newly formed pigments were detected and isolated from a 2-year-old Port wine through TSK Toyopearl HW-40(S) gel column chromatography characterized by UV−visible spectrophotometry, NMR, mass spectrometry (ESI/MS). 1H NMR 13C data for these obtained using 1D 2D techniques (COSY, NOESY, gHSQC, gHMBC) are reported the first time. The structure of was found to correspond vinyl cycloadducts malvidin 3-coumaroylglucoside bearing either procyanidin dimer or flavanol monomer ((+)-catechin (−)-epicatechin). Additionally, conformational analysis performed one pigment computer-assisted model building molecular mechanics. A chemical nomenclature is proposed unambiguously name this new family anthocyanin-derived pigments. Keywords: Red wine; flavanol; aging; pigments; anthocyanins; isomers; NMR;