CAS No 522-12-3 , 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-3-[(2S,3R,4R,5R,6S)-3,4,
5-trihydroxy-6-methyloxan-2-yl]oxychromen-4-one

Title: Quercitrin
CAS Registry Number: 522-12-3
CAS Name: 3-[(6-Deoxy-a-L-mannopyranosyl)oxy]-2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-1-benzopyran-4-one
Synonyms: quercitroside; quercimelin; quercetin-3-L-rhamnoside; thujin
Molecular Formula: C21H20O11
Molecular Weight: 448.38
Percent Composition: C 56.25%, H 4.50%, O 39.25%
Literature References: From Aesculus hippocastanum L., Hippocastanaceae: H?rhammer et al., Arch. Pharm. 292, 113 (1959). Structure: Zemplén et al., Ber. 61, 2486 (1928); Marchlewski, Skarzynski, Biochem. Z. 297, 56 (1938); Wolfrom, Thompson in R. L. Whistler, M. L. Wolfrom, Methods in Carbohydrate Chemistry vol. 1 (Academic Press, New York, 1962) p 202.
Properties: Yellow crystals from dil methanol or ethanol, mp 176-179°; from water, mp 167°. uv max (ethanol): 350, 258 nm (log e 4.18, 4.30). Practically insol in cold water, ether; sol in alc; moderately sol in hot water; sol in aq alkaline solns with intense yellow color which is oxidized by air to brown.
Melting point: mp 176-179°; mp 167°
Absorption maximum: uv max (ethanol): 350, 258 nm (log e 4.18, 4.30)
Use: Has been used as textile dye. Flavine yellow shade is prepared by extracting quercitron bark with high pressure steam and consists mainly of quercitrin: Tisdale, Can. Text. J. 57, 44 (1941).