Quercitin, quercitrin

Also sometimes given incorrectly as quercitin. Quercitrin is the glucoside (3-L-rhamnoside Colour Index, 1971, Cl 75720/Natural Yellow 10) in Quercus velutina Lam. bark. The Colour Index lists quercetin imder Cl 75670/Natural Yellow 10,13/Natural Red 1. 

Black catechu contains 2-12% /- and dl-ca. c-chin, 22-50% catechutannic acid, /- and [Pg.157]

Quercitin and quercitrin give beautiful yellow shades on cotton mordanted with alumina. With tin mordants a more orange shade is produced. On a large scale these bodies have an extensive application, and are used in form of a decoction of the bark or as flavin. In dyeing with the extract, it is probable that the quercitrin splits up, and that the shades obtained are due to the formation of quercitin lakes. 

Rutin, the glucoside contained in Chinese yellow berries and in the leaves of Ruta graveolens, is closely allied to quercitrin. On boiling with dilute acids it splits up into quercitin and a sugar [29,30,31]. 

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