兔尾草(Uraria crinita(L.)Desv. ex DC.)為豆科(Fabaceae)兔尾草屬(Uraria)多年生草本亞灌木,廣泛分布於中國大陸南部、海南島、香港、緬甸、泰國、菲律賓、爪哇及台灣等地。兔尾草根部以 95% 乙醇於室溫下反覆萃取三次,經過濾、濃縮後,95% 乙醇萃取物分別以正己烷、乙酸乙酯、正丁醇進行分配萃取,進一步進行乙酸乙酯層及正丁醇層萃取物之分離與純化,經由各種管柱層析及再結晶等方法,共得到十一個化合物,由物理和光譜數據解析,發現其中一個為新化合物,屬於 flavonoid結構的化合物(3),其它分別為 flavonoids 結構的化合物(1)、(4);phenolic acid 結構的化合物(2);amino acid結構的化合物(5);benzo-γ-pyrone glycosides結構的化合物(6)、(8);purine類的化合物(7);megastigmane glycoside結構的化合物(9);neolignan glycoside結構的化合物(10);pyrimidine類的化合物(11)。其中化合物(1)-(3),(5)-(11)為首次自兔尾草所分離出,化合物(3),(5)-(11)為首次自兔尾草屬所分離出。
Uraria crinita (L.) Desv. ex DC. (Fabaceae), is the perennial herb subshrub and widely distributed throughout southern China, Hainan Island, Hong Kong, Myanmar, Thailand, Philippines, Java and Taiwan. In the present study, the roots of U. crinita were extracted three times with 95% ethanol at room temperature. The 95% ethanol extract was filtered and concentrated under reduced pressure, then partitioned with a sequence of n-hexane, ethyl acetate (EtOAc) and n-butanol (n-BuOH). The EtOAc layer and n-BuOH layer were further isolated and purified. The constituents were obtained by a series of chromatographic analysis and recrystallization. Totally, eleven compounds including one new flavonoid (3), two known flavonoids (1) and (4), one phenolic acid (2), one amino acid (5), two benzo-γ-pyrone glycosides (6) and (8), one purine (7), one megastigmane glycoside (9), one neolignan glycoside (10) and one pyrimidine (11) were isolated and identified by spectral analysis. Among these compounds, compound (1) - (3), (5) - (11) were first isolated from U. crinita, compound (3), (5) - (11) were first isolated from the genus of Uraria.