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Showing 1 to 14 of 14 for “"Flash chromatography"”.
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Chromatographic Separation of Enantiomers of Some Physiologically Active Types of Compounds on Chiral Stationary Phases (Benzodiazepinones, Beta-Lactams, Beta-Aminoacids)
… types of compounds have been separated by chromatography on chiral stationary phases. Thus benzodiazepinone enantiomers and enantiomers of aryl substituted (beta)-lactams can be separated directly on amino acid derived chiral stationary phases, whereas (beta)-amino acid enantiomers can be …
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Purification, detection and biological effects of cyanobacterial toxins.
… with an established high-performance liquid chromatography (HPLC) protocol to devise an extraction procedure for saxitoxins from cyanobacterial cells. It was also suitable for screening acid extracts of shellfish flesh for saxitoxins and performed well in a large shellfish monitoring …
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Synthetic and spectroscopic studies of 6-substituted chromone derivatives
… compounds synthesized were purified either by flash chromatography or recrystallization using ethanol-water. The yields of chromone-2-carboxylic acids ranged from 85-90 %, those of the chromone-2-carboxamides ranged from 40-72 %, and for the Suzuki reaction the yields ranged from 40-55 %. The …
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Isolation, Structure Elucidation and Biological Evaluation of Natural Products From Plants and Fungi
… techniques including preparative thin layer chromatography, vacuum liquid chromatography, flash chromatography, high pressure liquid chromatography and over pressure layer chromatography were utilized to isolate biologically active secondary metabolites from natural products of fungal and …
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The development of azadirachtin as a soil-applied, granular insecticide
… isolated to approximately 95% purity using flash chromatography. This material was used in all subsequent chemical and biochemical studies. To increase the speed of crude extract analysis, a colorimetric technique was assessed to rapidly quantify azadirachtin. However, this method was …
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Design and synthesis of potential chrome-based anti-tuberculosis agents
… compounds were purified by recrystallization and flash chromatography, and then characterized using NMR and FTIR, LC-MS and HRMS. After fully characterizing target compounds, they were screened for activity against the Mtb H37Rv clinical strain. Three media were used for screening and MABA was …
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Oligomers of beta-L-arabinosides of hydroxyproline : synthesis of the carbohydrate epitope of the Art v 1 allergen
… The â-Ara-Hyp monomer could be isolated by flash chromatography. A dimer of â-Ara-Hyp was prepared by deprotection of the N- and C- termini of the â-Ara-Hyp monomer respectively, after which peptide coupling of the two compounds was performed using HATU as coupling reagent to give the …
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I. Collagen-like polypeptides. II. Helix-turn-helix peptides and turn mimetics
… the resulting diastereomers was separable by flash chromatography, and the absolute stereochemistry of the two diastereomers was determined by Mosher's method. The Gly-Pro alkenyl peptides, and their control peptide Ac-(Gly-Pro-Hyp)8-Gly-Gly-Tyr-NH2 were synthesized and purified. All three …
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Exploitation of underused Streptomyces through a combined metabolomics-genomics workflow to enhance natural product diversity.
… culture supernatant and agar crude extract by flash chromatography, resulting in semi-purified fractions. The predominant metabolite families in fractions were actinomycins and deferoxamines, which were further split by polarity into separate fractions. This resulted in rapid purification of …
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Investigation of the production and isolation of bioactive compounds from cyanobacteria.
… KAC 66 was fractionated by reversed phase flash chromatography and their toxicity was determined by their lethality to Daphnia pulex and D. magna along with inhibition of protein phosphatase 1 assay (PP1). All fractions showed lethality to Daphnids and inhibitory activity against PP1, the …
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Anti-inflammatory and anti-colon cancer potential of yerba mate (Ilex paraguariensis St. Hilaire) bioactive constituents
… partially purified and quantified by preparative chromatography, HPLC and LC/ESI-MS-MS. Yerba mate contained 10–15 mg/g dry weight total saponins. Mate saponins significantly inhibited iNOS, PGE2 and COX-2 and reduced nuclear translocation of NF- κB subunits p50 (49.8%) and p65 (49.0%). Mate …
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Extraction and Purification of Gamma-Tocotrienol from Rice Bran Oil Deodorizer Distillate
<p>The tocols (alpha-, beta-, gamma- and delta- tocopherols (T); alpha-, beta-, gamma- and delta-tocotrienols (T3)) make up the vitamin E family of antioxidants. Tocols have many health benefits. Gamma-T3 has been shown to protect against harmful radiation effects in mice. During rice bran oil …
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Chemistry of hydroxycinnamate esters and their role as precursors to Dekkera produced off-flavour in wine.
… acids (3 and 4), which could be separated by flash chromatography, though the pure cis-isomers isomerised rapidly under ambient conditions and slowly under red light back to the trans-isomers. Stable isomeric mixtures were achieved by irradiation with ultra-violet light giving mixtures of …
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Isolation and characterization of African marine natural products and repositioning of the natural product antibiotic fusidic acid and privileged benzimidazole scaffold for tuberculosis and malaria
… a combination of normal phase benchtop column chromatography, preparative TLC, and semi-preparative HPLC. Elucidation of the chemical structures was accomplished by 1D- and 2D-NMR, HR-ESI-MS, UV and IR spectroscopic techniques, and X-ray diffraction analysis. The isolated compounds belong to …