Chem. [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.
1857. Miller, Elem. Chem., II. 512. When quercitrin is boiled with dilute sulphuric or hydrochloric acid, it is decomposed into glucose and quercetin.
1872. Watts, Dict. Chem., 1st Suppl. 982. Gintl … has found quercetin in the leaves of the ash-tree.
Hence Quercetamide, an amide obtained from quercetin in the form of an amorphous orange-yellow powder. Quercetic a., derived from quercetin, as in quercetic acid.
1868. Watts, 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.
1893. T. E. Thorpe, Dict. Chem., III. 324. If the melting is continued longer than necessary to obtain quercetic acid, then quercimeric acid is obtained.
