Noroleanane-type triterpenoids from Dolichos trilobus L. and their anti-α-glucosidase activities
Ming Luo1, Yan-Hong Li1, Ya Lu1
1Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, School of Ethnomedicine and Ethnopharmacy, Yunnan Minzu University, Kunming, China.
Abstract:
Falcatane A (1) and B (2), 4-oxo-3,24-dinor-2,4-secooleanane- and 3-oxo-24- noroleanane-type triterpenoids, together with seven known triterpenoids involving 2-hydroxy-3-oxo-24-noroleana-1,4,12-trien-28-oic acid (3) and oleanolic acid (4), were separated from the ethyl acetate roots extract of Dolichos trilobus using the column chromatography of silica gel, MCI gel, and Sephadex LH-20. The compounds were determined by analysis of IR, NMR spectroscopic data and mass spectrometry. In the bioassay, all isolates showed varying degree of the α-glucosidase inhibitory activity except compound 2.
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