The present study was designed to investigate the chemical constituents of the whole herb of Dichrocephala benthamii. A new megastigmane glucoside(compound 1), together with its four known analogues(compounds 2-5), was obtained. Their structures were elucidated on the basis of spectroscopic analyses(UV, IR, MS, and 1D and 2D NMR). The absolute configuration of compound 1was assigned on the basis of CD method and chemical evidence. In addition, their cytotoxicity against human hepatoma cells(Hep G-2) was evaluated by the MTT method. Compound 5 showed weak activity against Hep G-2, while the other compounds did not show remarkable inhibitory effects.
SONG BoSI Jin-GuangYU MengTIAN Xiao-HuiDING GangZOU Zhong-Mei
The present study was designed to determine the chemical constituents and identify new components of the leaves of Aquilaria sinensis （Lour.） Gilg. The compounds were isolated and purified by repeated silica gel, Sephadex LH-20, and ODS column chromatography and their structures were elucidated by NMR and HR-ESI-MS spectrometry. Eight megastigmane glycosides and two cucurbitacins were isolated and identified as （95） megastigma-4,7-diene-2,3,9-triol 9-O-β-D-glucopyranoside （1）, （9S） megastigma-4（13）,7-diene-3,6,9-triol 9-O-β-D-glucopyranoside （2）, macarangloside D （3）, corchoionoside C （4）, staphylionoside H （5）, （＋） 3-oxo-a-ionol-β-D-glucopyranoside （6）, （-） 3-oxo-α-ionol-β-D-glucopyranoside （7）, citroside B （8）, 2-O-β-D-glucopyranosyl cucurbitacin I （9）, bryoamaride （10）. Compounds 1 and 2 were newly identified megstigmane glucosides and reported from this genus for the first time.
SUN JianXIA FangWANG ShuWANG Ke-YuanCHEN Jin-MingTU Peng-Fei
