The electronic transitions of analogs of red wine pyranoanthocyanin pigments.

摘要: There is increasing interest in using natural colorants like anthocyanins cosmetics, food and pharmaceuticals as replacements for synthetic colorants. During the maturation of red wines, anthocyanin pigments contained grapes are transformed via reaction with copigments metabolic products into pyranoanthocyanins, responsible part final color wine. In order to understand structural effects on absorption spectra calculated excited state energies spectroscopic states a series substitued pyranoflavylium cation analogs pyranoanthocyanins have been compared experimental data these compounds. The vertical excitation energies, by ADC(2) approach, gave excellent agreement UV-Vis nature lowest correlates observed photophysical behavior solution. present results thus provide basis design new chromophores desired colors photophysics, well understanding analogous properties pyranoanthocyanin