Megastigmanes from an aqueous extract of Uncaria rhynchophylla / 药学学报

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.

Chemical constituents from the leaves of Broussonetia papyrifera / 药学学报

To separate and identify the chemical constituents from the leaves of Broussonetia papyrifera (Linn.) Vent, various columns including Diaion HP-20, Toyopearl HW-40C, Sephadex LH-20, silica gel were employed for the isolation and purification of compounds from the leaves of B.papyrifera. The structures of the compounds were elucidated by their physiochemical characteristics and spectral data. Nineteen compounds were isolated from the leaves of B.papyrifera and their structures were identified as apigenin (1), apigenin-7-O-β-D-glucopyranoside (2), chrysoerid-7-O-β-D-glucopyranoside (3), apigenin-7-O-β-D-glucopyranuronide (4), vitexin-7-O-β-D-glucopyranoside (5), luteolin (6), 5,7,4′-trihydroxyl-6-C-[a-L-rhamnopyranosyl(1→2)]-β-D-glucopyranosyl flavone (7), 5,7,4′-trihydroxyl-8-C-[a-L-rhamnopyranosyl(1→2)]-β-D-glucopyranosyl flavone (8), saponaretin (9), vitexin (10), benzyl benzoate-2,6-di-O-β-D-glucopyranoside (11), (2R,3R,5R,6S,9R)-3-hydroxy-5,6-epoxy-β-ionol-2-O-β-D-glucopyranoside (12), (2R,3R,5R,6S,9R)-3-hydroxyl-5,6-epoxy-acetyl-β-ionol-2-O-β-D-glucopyranoside (13), ficustriol (14), (6S,9S)-roseoside (15), 3β-hydroxy-5α,6α-epoxy-β-ionone-2α-O-β-D-glucopyranoside (16), icariside B1 (17), sammangaoside A (18), 3-hydroxy-5α,6α-epoxy-β-ionone (19). Compounds 11, 12 and 13 are new compounds, the others are isolated from this genus Broussonetia for the first time.