Figure 4. Structure of flavonols: kaempferol (R1=R2=H); quercetin (R1=OH, R2=H); isorhamnetin (R1=OCH3, R2=H); myricetin (R1=R2=OH); laricitrin (R1=OCH3, R2=OH); siringetin (R1=R2=OCH3). a) flavonol-3-O-glucoside; b) flavonol-3-O-galactosideo; c) flavonol-3-O-glucuronideo; d) rutin (quercetin-3-O-(6”-ramnosil)-glucoside) [35]

From

Vinification By-products and Their Phenolic Compounds

Milene Teixeira Barcia, Paula Becker Pertuzatti, Vivian Caetano Bochi, Isidro Hermosín-Gutiérrez, Helena Teixeira Godoy

American Journal of Food Science and Technology. 2015, 3(4A), 18-23 doi:10.12691/ajfst-3-4A-4