Nomenclature
CAS number: 491-50-9
2-(3,4-Dihydroxyphenyl)-7-(β-
d-glucopyranosyloxy)-3,5-dihydroxy-4
H-1-benzopyran-4-one; quercetin-7-
d-glucoside; 3,3′,4′,5,7-pentahydroxyflavone-7-
d-glucoside.
C
21H
20O
12; mol wt 464.38.
C 54.31%, H 4.34%, O 41.34%.
Description and references
Found in flowers of Gossypium herbaceum L., Malvaceae: Perkin, J. Chem.
Soc. 95, 2181 (1909); from leaves of Chrysanthemum
ségetum L. and C. coronarium L., Compositae: Geissman, Steelink, J. Org. Chem. 22, 946 (1957); Anyas, Steelink, Arch. Biochem. Biophys. 90, 63 (1960). In
the mother liquor from quercimeritrin the glucosides gossypitrin and isoquercitrin, q.v., are also found.
Structure: Attree, Perkin, J. Chem. Soc. 1927, 234; Rao, Seshadri, Proc.
Indian Acad. Sci. 9A, 365 (1939), C.A. 34, 1071 (1940);
Pacheco, Grouiller, Compt. Rend. 253, 1178 (1961).
Derivative
Trihydrate.
Properties
Yellow plates from aq pyridine. The water of
crystn is given up at 100°, the anhydr material is hygroscopic, mp 247-249°. uv max (ethanol): 372, 257 nm (log ε 4.33, 4.38). Practically insol in cold water, more sol in hot water; sol in
methanol. Sol in aq alkaline solns with deep yellow color. Is hydrolyzed
by 7% H2SO4 yielding 1 mol quercetin and 1 mol d-glucose.