Publications by authors named "Yajian Guo"

A new compound, mucic acid 3-O-gallate (1), was isolated from the fruit of Phyllanthus emblica L, together with 5 known compounds (2-6). Their structures were elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR techniques, and by comparison with literature data.

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To study the constituents of the Prunella vulgaris L, the constituents were isolated by various column chromatography and the structures were identified on the basis of chemical and spectral analysis. One saponin compound (I) and one flavone glycoside compound (II) were obtained from Prunella vulgaris L. Their structures were elucidated as 16-oxo-17-demethyl-3beta,24-dihydroxylolean-12-en-3-O-beta-D-glucuronoside (I), and acacetin-7-O-beta-D-glucopyranoside (II).

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Objective: To study the chemical constituents in the spikes of Schizonepeta tenuifolia.

Method: Compounds were isolated and purified with silica gel, ODS and Sephadex LH-20 gel column chromatography, and their structures were determined by using spectroscopic analysis including MS and NMR.

Result: Nine compounds were isolated and identified as 5, 7-dihydroxy-6, 4'-dimethoxyflavone (1), 5, 7-dihydroxy-6, 3', 4'-trimethoxyflavone (2), ursolic acid (3), 3-hydroxy-4(8)-ene-p-menthane-3(9)-lactone (4), 5, 7, 4'-trihydroxyflavone (5), 5, 4'-dihydroxy-7-methoxyflavone (6), hesperidin (7), luteolin (8) and daucesterol (9).

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Objective: To study the chemical constituents in the active parts of Huoxue Yiqi Tang.

Method: The silica gel, Sephadex LH-20 were used to isolate the compounds, El, FAB-MS and 1D, 2D-NMR were used to identify the obtained compounds.

Result: 14 compounds were obtained from the prescription.

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Aim: To investigate the chemical constituents from Picria fel-terrae Lour.

Methods: Column chromatography techniques were used to isolate the chemical constituents, physico-chemical constants and spectroscopic analysis were employed for structural elucidation. Results Two triterpenoids named picfeltarraenone I (1) and picfeltarraenin XI (2) were isolated, and their structures were established to be 3,11,22-trioxo-16alpha-hydroxy-(20S,24)-epoxy-cucurbit-5,23-diene (1) and 3,11,22-trioxo-16alpha-hydroxy-(20S,24)-epoxy-cucurbit-5, 23-diene-2beta-O-beta-D-glucopyranoside (2), respectively.

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Objective: To isolate and identify compounds from Picria fel-tarrae in order to utilize it better.

Method: Constituents from Picria fel-tarrae were isolated by several column chromatography and their structures were elucidated on the basis of chemical and spectral analysis.

Result: Six compounds, N-benzoylphenylalanyl-L-phenylalaninol acetate (1), 1-hydroxy-7-hydroxymethyl-9,10-anthraquinone (2), 9, 16-dioxo-10,12,14-octadeca-trienoic acid (3), 5,7,4'-trihydroxy-flavone (4), beta-sitosterol (5), and daucosterol (6) were obtained from the fraction with relatively low polarity of EtOH extract of Picria fel-tarrae.

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Aim: To study compounds isolated from Picria fel-terrae.

Methods: The chemical constituents were separated and purified by column chromatography on silica gel and MCI. Their structures were identified on the basis of spectral data (IR, UV, MS, ID NMR and 2D NMR).

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Objective: To investigate the chemical constituents of Tibetan medicine Phyllanthus emblica.

Method: Various chromatographic techniques were employed for isolation and purification of the constituents, and the structures were elucidated by chemical and spectral analyses.

Result: 11 compounds were isolated and identified as gallic acid (I), ellagic acid (II), 1-O-galloyl-beta-D-glucose (III), 3,6-di-O-galloyl-D-glucose (IV), chebulinic acid (V), quercetin (VI), chebulagic acid (VII), corilagin (VIII), 3-ethylgallic acid (3-ethoxy-4,5-dihydroxy-benzoic acid, IX), isostrictiniin (X), 1,6-di-O-galloyl-beta-D-glucose (XI).

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Aim: To investigate the chemical constituents of Phyllanthus urinaria L.

Methods: Various chromatographic techniques were employed for the isolation and purification. The structure was elucidated by spectral analyses.

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Aim: To study the effect of 3,4-oxo-isopropylidene-shikimic acid (ISA) on H2O2 (200 mol.L-1, 4 h) injured human umbilical vein endothelial cells (HUVEC).

Methods: Morphological change was observed under microscop.

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Aim: To examine the effect of 3,4-oxo-isopropylidene-shikimic acid (ISA) on human polymorphonuclear leukocyte (PMN) adhesion to human umbilical vein endothelial cells (HUVEC) and explore its mechanism.

Methods: Adhesion of PMN to HUVEC was measured by rose bengal staining assay. Cell-ELISA and RT-PCR methods were used to examine the expression of adhesion molecules ICAM-1.

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Objective: To study the chemical constituents in the root of Cichorium intybus.

Method: The compounds were isolated and identified by column chromatography and NMR, IR, MS data.

Result: Twelve compounds were isolated and identified.

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Aim: To study the effect of 3,4-oxo-isopropylidene-shikimic acid (ISA) against arteriovenous shunt and middle cerebral artery thrombosis (MCAT) in rats.

Methods: Arteriovenous shunt model was adopted to measure thrombus weight; The neurologic deficit (ND) and the infarct size (IS) of the middle cerebral thrombosis (MCAT) model induced by FeCl3 were observed; The effect of ISA on platelet aggregation rate of rat and rabbit by giving ISA in vivo and in vitro was studied.

Results: ISA 25, 50, 100 and 200 mg.

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