Xiao-Jia Hu

Ainsliatrimers A and B, the First Two Guaianolide Trimers from Ainsliaea fulvioides

Ainsliatrimers A (1) and B (2), the first two guaianolide-type sesquiterpene lactone trimers, together with one new structurally related sesquiterpene dimer ainsliadimer B (3), were isolated from the aerial part of Ainsliaea fulvioides. Their structures were elucidated by spectroscopic techniques, including X-ray crystal diffraction. Both 1 and 2 showed potent cytotoxicites against LOVO and CEM cell lines.

Qualitative and quantitative determination of the major coumarins in Zushima by high performance liquid chromatography with diode array detector and mass spectrometry.

A method, high-performance liquid chromatography coupled with diode array and electrospray tandem mass spectrometry (HPLC-DAD-ESI-MS), was developed to qualitatively identify and quantitatively determine the 10 major active coumarins of Zushima. The analysis was performed by using a ZORBAX SB-C18 analytical column (250 mm x 4.6 mm ID, 5 microm) at gradient elution of 0.5% aqueous formic acid and acetonitrile with diode array detection (325 nm). The method was validated for linearity, precision, accuracy, limit of detection and quantification. The proposed method was successfully applied for the qualitative and quantitative analysis of 10 coumarins in five different species of Zushima which had great variation on the contents of investigated coumarins.

Blumeaenes A-J, Sesquiterpenoid Esters from Blumea balsamifera with NO Inhibitory Activity

Chemical examination of the ethanol extract of the aerial parts of Blumea balsamifera led to the isolation of ten new sesquiterpenoid esters, blumeaenes A-J (1- 10), with 13 known flavonoids. Their structures were determined mainly by use of 1D and 2D NMR spectroscopic techniques. All sesquiterpenoid esters were tested for their inhibitory activity against LPS-induced NO production in RAW264.7 macrophages. Compounds 1, 4 and 5 showed slight inhibitory effect on the production of NO with IC(50) values of 40.06, 46.35 and 57.80 microg/mL, respectively.

Two new coumarins from Edgeworthia chrysantha.

Two new coumarins, 8-[3-(2,4-benzenediol)-propionic acid methyl ester]-coumarin-7-β-D-glucoside (1) and 7-hydroxyl-odesmethoxyrutarensin (2), were isolated from the stems and barks of Edgeworthia chrysantha. Their structures were elucidated on the basis of spectroscopic data interpretation.