钩藤水提取物中的微量三萜酸类

Minor triterpenoid acids from an aqueous extract of Uncaria rhynchophylla

运用大孔吸附树脂、MCI树脂、Sephadex LH-20、Toyopearl HW-40C、正相硅胶和C18反相硅胶等多种固定相柱色谱,结合闪式色谱和高效液相色谱分离技术,从常用中药钩藤水煎液中分离得到17个(1~17)微量三萜酸类化合物。通过HR-ESI-MS、UV、CD、IR及1D和2D NMR波谱数据解析鉴定了它们的结构,其中8个为新化合物(1~8),依次命名为钩藤酸Q~X,且化合物2和7的结构得到单晶X-射线衍射分析的确证。在初步体外活性筛选中,在5μmol·L^(-1)浓度下,27-羟基齐墩果酸(17)对TGF-β诱导的HSC-T6细胞活化有一定抑制作用。

Seventeen minor triterpenoid acids(1−17)were isolated from an aqueous decoction of Uncaria rhynchophylla by a combinatory application of column chromatography using multiple stationary phases,including macroporous adsorbent resin,MCI resin,Sephadex LH-20,Toyopearl HW-40C,silica gel,and C18 reversed phase silica gel,combined with separation techniques of flash chromatography(FC)and high performance liquid chromatography(HPLC).Their structures were determined by analysis of HR-ESI-MS,UV,CD,and IR as well as 1D and 2D NMR spectroscopic data,of which eight new compounds(1−8)are named successively uncarinic acids Q-X,while the structures of 2 and 7 were confirmed by single crystal X-ray diffraction.In the in vitro assays,27-hydroxyolean-12-en-28-oic acid(17)inhibited TGF-β-induced HSC-T6 cell activation at the concentration of 5μmol·L^(-1).