Résumé
Five new megastigmanes (1-5) were isolated from a decoction of Uncaria rhynchophylla by separation techniques of column chromatography using a combination of multiple stationary phases, including macroporous adsorbent resin, MCI resin, silica gel, Sephadex LH-20, and Toyopearl HW-40F, and reversed phase HPLC. Their structures were characterized by spectroscopic data analysis of HR-ESI-MS, NMR, and CD, in combination with Mosher's mothed as well as ECD and NMR calculations. The new compounds were named uncarphyllonone A (1), uncarphyllonols A (2) and B (3), and uncarphabscisic acids A (4) and B (5). Although the structures of 3 and 4 were previously reported, the reported NMR spectroscopic data were incorrect or do not support the assigned structures in literatures. This is also the first report of discovery of new megastigmane natural products from the Uncaria genus.
Résumé
Objective To study the constituents from the berry of Panax ginseng. Methods Compounds were separated and purified by column chromatographic methods. Their structures were elucidated by physicochemical properties and spectral analyses. Results Twelve compounds were isolated from water extracts of the berry of P. ginseng. They were identified as benzoic acid (Ⅰ), isoginsenoside-Rh3 (Ⅱ), ginsenoside-Rh2 (Ⅲ), ginsenoside-Rh1 (Ⅳ), ginsenoside-Rg1 (Ⅴ), ginsenoside-Re (Ⅵ), ginsenoside-Rd (Ⅶ), ginsenoside-Rc (Ⅷ), ginsenoside-Rb2 (Ⅸ), ginsenoside-Rb1 (Ⅹ), ?-sitosterol (Ⅺ), and 20-O-?-D-glucopyranosyl-20 (S)-protopanaxadiol named as compound K (ⅩⅡ). Conclusion The compound K is a new natural product.
Résumé
Objective To study the chemical constituents from the wing twigs of Euonymus alatus. Methods Compounds were isolated and purified repeatedly on silica gel, Sephadex LH-20, open RP-C18 column chromatographies and PTLC, and their chemical structures were elucidated by their physicochemical properties and spectral data, such as 1H-NMR, 13C-NMR, and EI-MS. Results Nine compounds were obtained and identified as: epifriedelinol (Ⅰ), stigmast-4-en-3-one (Ⅱ), 6?-hydroxy-stigmast-4-en-3-one (Ⅲ), ?-sitosterol (Ⅳ), methyl 2, 4-dihydroxy-3, 6-dimethyl benzoate (Ⅴ), methyl 2, 4-dihydroxy-6-methyl benzoate (Ⅵ), 7-methoxy-4-methylphthalide (Ⅶ), vanillin (Ⅷ), n-octacosanol (Ⅸ). Conclusion Compound Ⅶ is first reported as a natural product. Compounds Ⅴ-Ⅷ are reported from plants of Euonymus L. for the first time.