摘要:
The new triterpenoid cycloartane cycloorbigenin C, the structure of which is 23xi,24xi-cycloartan-3beta,6alpha,16beta,23,24,25-hexaol, was obtained from the aerial part of Astragalus orbiculatus Ledeb. (Leguminosae). The structure of cycloorbigenin C was proved using chemical transformations, IR spectroscopy, electron-impact mass spectrometry, and PMR and C-13 NMR spectra interpreted using J-modulation and the 2D NMR spectroscopies: H-1-H-1 COSY, TOCSY, ROESY, HSQC, and HMBC.