Quercetin

Another name：
2-(3,4-Dihydroxyphenyl)-3,5,7-trihydroxy-4H-1-benzopyran-4-one;
Sophoretin, Meletin; 3,3′,4′,5,7-Pentahydroxyflavone

CAS Number: 117-39-5
Beilstein Reference：317313
ChEMBL: ChEMBL50
Chemical formula; C15H10O7
Appearance:yellow crystalline powder
Molar mass:302.236 g/mol
Density: 1.799 g/cm3
Melting point:316 °C (601 °F; 589 K)
Solubility：Practically insoluble in water;
soluble in aqueous alkaline solutions
Flash point239.5 °C
Molar refractive index: 73.31
molar volume (cm3/mol): 167.9
Parachor (90.2K): 549.9
Surface tension (dyne/cm): 114.8
Polarizability (10-24cm3): 29.06

Quercetin is a plant flavonol from the flavonoid group of polyphenols. It is found in many fruits, vegetables, leaves, seeds, and grains; capers, red onions, and kale are common foods containing appreciable amounts of it. It has a bitter flavor and is used as an ingredient in dietary supplements, beverages, and foods. Quercetin has been reported to inhibit the oxidation of other molecules and hence is classified as an antioxidant in vitro. It contains a polyphenolic chemical substructure that stops oxidation in vitro by acting as a scavenger of free radicals. Quercetin has been shown to inhibit the PI3K/AKT pathway leading to downregulation of the anti-apoptotic protein Bcl-w. Quercetin activates or inhibits the activities of a number of proteins in vitro. For example, it is a nonspecific protein kinase enzyme inhibitor.