51154-08-6Relevant academic research and scientific papers
Aged red wine pigments as a source of inspiration for organic synthesis - The cases of the color-stable pyranoflavylium and flavylium-(4→8)-flavan chromophores
Chassaing, Stefan,Isorez-Mahler, Géraldine,Kueny-Stotz, Marie,Brouillard, Raymond
, p. 3066 - 3078 (2015/05/04)
Two flavylium-based chromophores peculiar to aged red wine pigments are investigated from a synthetic viewpoint. The condensation between easy-to-prepare 5-hydroxy-4-methylflavylium salts and aldehydes, giving birth to color-stable pyranoflavylium pigments, further proves efficient and wide in scope. A set of some twenty structurally-related flavylium-based pigments has been prepared and structure:color relationships are discussed. Furthermore, the synthesis of the flavylium-(4→8)-flavan chromophore is achieved via a novel three-step sequence. The elaborated sequence starts with an iodine-magnesium exchange from an 8-iodinated flavan, thus generating a magnesiated species that then smoothly reacts with a flavone to furnish an adduct, that finally leads to the expected chromophore via dehydration.
Proton magnetic resonance spectra of catechin and bromocatechin derivatives: C6- vs. C8-substitution
Kiehlmann, E.,Tracey, A. S.
, p. 1998 - 2005 (2007/10/02)
The 1Hmr spectra of 20 catechin derivatives substituted at C-6/C-8 by bromine and/or hydrogen and at oxygen by methyl, acetyl, and/or hydrogen have been analyzed in deuterated acetone, acetonitrile, and chloroform.Because of its dependence on the nature o
