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OBJECTIVE:To study the chemical constituents of Euonymus amygdalifolius.METHODS:Silica gel column chromatogram,gel column chromatogram,TLC and semi-preparative HPLC were adopted to isolate and purify ethanol extract from E.amygdalifolius.The structure of compounds was analyzed and identified according to physical and chemical properties,spectral data (mass spectrurn,hydrogen spectrum and carbon spectrum).RESULTS:Ten compounds were isolated from ethanol extract of aerial part of E.amygdalifolius,i.e.taraxerol (1),sophoradiol (2),taraxerone (3),sorghumol (4),heptaecanoic acid (5),octadecenoic acid (6),β-Sitosterol (7),daucosterol (8),epifriedelinol (9) and friedelin (10).CONCLUSIONS:Above compounds are all isolated from E.amygdalifolius for the first time;compounds 1,2,4,5,6 are isolated and obtained from Euonymus A.for the first time.The study lay a foundation for quality evaluation of E.amygdalifolius.
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Chemical investigation of the dichloromethane extracts of Hoya buotii Kloppenb. afforded taraxerone (1), taraxerol (2), a mixture of β-sitosterol (3a) and stigmasterol (3b) in about 2:1 ratio, and a mixture of α-amyrin cinnamate (4a) and β-amyrin cinnamate (4b) in about 1:2 ratio from the stems; 1, 2, and 3a from the roots; a mixture of 4a and 4b in about 3:2 ratio from the flowers; and 3a, squalene (5) and saturated hydrocarbons from the leaves. The structures of 1-5 were identified by comparison of their NMR data with those reported in the literature.
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Objective: To investigate the chemical constituents from the pods of Glycine max. Methods: The chemical constituents were isolated by repeated silica gel chromatography, Sephadex LH-20 gel column chromatography, medium pressure column chromatography, and semi-preparative liquid chromatography. Their structures were elucidated by chemical properties and spectroscopic analyses. Results: Fourteen compounds were identified to be 4,4'-diphenylmethane-bis (ethyl) carbamates (1), 2,6-dimethoxy-1,4-benzoquinone (2), (+)-medioresinol (3), taraxerone (4), lupenone (5), 7,3',4'-trihydroxyflavone (6), coumestrol (7), indole-3-carboxylic acid (8), apigenin (9), phaseol (10), 7,4'-dihydroxyflavone (11), stigmasterol (12), β-sitosterol (13), and β-daucosterol (14). Conclusion: Compounds 1-5 are obtained from the pods of G. max for the first time, and compound 6 is obtained from this plant for the first time.
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Objective: To study the chemical constituents from the barks of Quercus mongolica. Methods: The chemical constituents were isolated and purified on the base of silica gel column chromatography and HPLC method. The structural elucidation was performed according to the physicochemical properties and spectral analysis. Results: Twenty compounds were isolated and identified as taraxerone (1), taraxerol (2), 20β-hydroxydammara-23-en-3-one (3), 20 (S), 24 (S)-dihydroxydammara-26-en-3-one (4), ursotic acid acetate (5), lupeol (6), β-sitosterone (7), isofouquierol (8), gallic acid (9), 5, 6, 7, 4'-tetrahydroxyflavanone (10), taxifolin (11), scopoletin (12), kaempferol (13), β-sitosterol (14), secoisolariciresinol (15), erythrodiol (16), (-)-epicatechin (17), daucosterol (18), (-)-epipinoresinol (19), and salicylic acid (20). Conclusion: Compounds 1, 2, 5, 6, and 11 are isolated from this plant for the first time, and compounds 4, 7, and 8 are isolated from the plants of Quercus L. for the first time.
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Objective: To isolate compounds from K. pinnata and elucidate their structures and to explore preliminary antioxidant, antimicrobial, cytotoxic and thombolytic activities of extractives of the plant. Methods: The methanol extract of whole plant of K. pinnata has been subjected to different chromatographic separation and purification processes to isolate the secondary metabolites. The structures of the isolated compounds have been elucidated by extensive NMR studies. The free radical scavenging activity of the crude extract and its different Kupchan fractions were determined on stable radical DPPH. In vitro antimicrobial activity was determined by the disk diffusion method. Cytotoxicity screening has been performed against Artemia salina. Total phenolics content, membrane stabilizing activity and thombolytic activities were assessed by following established protocol. Results: The isolated compounds were identified as glut-5(6)-en-3-one, taraxerone, 3β-friedelanol, β-amyrin-3-acetate, 3,5,7,3',5'-pentahydroxyflavone and β-sitosterol. The chloroform soluble fraction showed potent antioxidant activity of (IC50=80.0 μg/mL) and significant cytotoxicity, while the crude extract demonstrated noticeable total polyphenol content (149.24 mg of GAE/gm of extractive), moderate membrane stabilizing activity and inhibition of clot lysis of blood. Conclusions: The obtained results rationalize the folkloric use of the plant and can be further investigated to isolate the active compounds responsible for the biological activities.
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Purpose: Dregea volubilis Benth, commonly known as Jukti in Bengal, is used in the treatment of boils and abscesses from ancient times. The purpose of this study is to elucidate the active compounds and as well as their anti-leishmanial and anti-tumour activities. Methods: Dried and crushed fruits of Dregea volubilis were extracted by petroleum ether (40 - 60°C); the best solvent system had first been verified by analytical Thin Layer Chromatography (TLC). The extract was subjected to TLC and column chromatography (CC) to isolate the pure compounds. Spectra data were obtained by Infra Red pectroscopy, Mass Spectroscopy and Nuclear Magnetic Resonance - Proton Magnetic Resonance (PMR), Carbon Magnetic Resonance (CMR) and Distortionless Enhancement by Polarization Transfer (DEPT) - for structure elucidation of the isolated compound(s). One of the compounds isolated was screened for anti-leishmanial activity against promastigotes of Leishmania donovani and anti-tumour activity on K562 leukemic cell line. Results: A pentacyclic triterpenoid compound was isolated and designated as taraxerone, and then characterized as d-friedoolean-14-en, 3 one together with ß-sitosterol and a long chain lipid fraction.. This compound showed in vitro anti-leishmanial activity against promastigotes of Leishmania donovani(strain AG 83) and anti-tumour activity on K562 leukemic cell line. Conclusion: A pentacyclic triterpenoid compound designated as taraxerone and characterized as Dfriedoolean-14-en, 3 one together was successfully isolated. The structure was determined on the basis of spectral analysis (IR, MASS, NMR (PMR, CMR and DEPT) and the compound demonstrated in vitro anti-leishmanial and anti-tumour activities