Abstract:
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 5 μmol·L
-1.