| 单词 |
quercetin |
| 释义 |
quercetin Chem.|ˈkwɜːsɪtɪn|
[Arbitrarily f. L. querc-us oak + -in1. (Cf. L. quercētum an oak-wood.)]
A yellow crystalline substance widely distributed in the vegetable kingdom, but usually obtained by decomposition of quercitrin; 3, 3′, 4′, 5, 7-Pentahydroxyflavone, C15H10O7.
1857Miller Elem. Chem. iii. 512 When quercitrin is boiled with dilute sulphuric or hydrochloric acid, it is decomposed into glucose and quercetin. 1872Watts Dict. Chem. 1st Suppl. 982 Gintl..has found quercetin in the leaves of the ash-tree. 1949Thorpe's Dict. Appl. Chem. (ed. 4) IX. 300/2 Quercetin gives red-brown, brown-orange, bright orange and olive-black shades on wool mordanted with chromium, aluminium, tin, and iron, respectively. 1962T. R. Seshadri in T. A. Geissman Chem. Flavonoid Compounds ii. 9 Quercetin and its glycosides can be conveniently extracted by borax and can be liberated by acidification.
Hence querˈcetamide, an amide obtained from quercetin in the form of an amorphous orange-yellow powder. quercetic |kwɜːˈsɛtɪk| a., derived from quercetin, as in quercetic acid.
1868Watts Dict. Chem. V. 3 On adding ammonia to the acid filtrate, quercetamide is obtained. Ibid. 5 Quercetin heated with potash yields quercetic acid and other products. 1893T. E. Thorpe Dict. Chem. III. 324 If the melting is continued longer than necessary to obtain quercetic acid, then quercimeric acid is obtained. |
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