4 results about "Chromatographic separation" patented technology

The invention provides a method for extracting and separating astragalin from the plant Mesona chinensis Benth. The method comprises the following steps: using the water-acetone solution for Mesona chinensis Benth for extraction, concentrating and drying the extract to obtain a crude extract, performing chromatographic separation to the crude extract with a macroporous adsorption resin column, collecting eluent, concentrating and drying the eluent to obtain a fine extract, processing the fine extract through high performance liquid chromatography to separate and prepare an astragalin pure product with the purity of 99%. The raw material of the invention is cheap and accessible and barely causes environmental pollution; the technology is simple, practical and fast; and the obtained astragalin has high purity and suitable for mass industrial production.

The invention provides a method for quantifying Apis cerana cerana honey MRJP2 through liquid chromatography-tandem mass spectrometry. The characteristic peptide fragment of royal jelly major protein2 (MRJP2) is screened out for Apis cerana cerana honey, a quantitative method of liquid chromatography tandem mass spectrometry is developed, and the method comprises the steps of screening of the characteristic peptide fragment, making of a standard curve, performing sample pretreatment, performing liquid chromatography separation and tandem mass spectrometry detection, and carrying out softwarequantification of the peptide fragment and the like. The quantitative method for the Apis cerana cerana honey MRJP2 provided by the invention has the advantages of high accuracy, precision and sensitivity and strong stability, and is suitable for accurately quantifying the Apis cerana cerana honey MRJP2. The method can be used for assisting Apis cerana cerana honey authenticity evaluation. In addition, the quantitative method has important practical significance in protecting rights and interests of honey consumers and maintaining healthy development of the bee product industry.

The invention relates to a preparation method of a tobacco precursor-aroma monomer pyrazine-2-formate. The method includes the steps of: dissolving pyrazine-2-formic acid and beta-ionol in dry dichloromethane, performing stirring for 10min-30min, adding 4-dimethylamino pyridine and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, conducting stirring at room temperature for 4-12h, carrying out TLC monitoring reaction, and tracking the reaction end point, adding water into an organic phase for washing, separating liquid, then using a saturated sodium chloride solution to perform washing, and separating liquid, drying the organic phase with anhydrous Na2SO4, and performing concentration to obtain a crude product, and carrying out column chromatographic separation so as to obtain the product. Compared with geraniol and beta-ionol precursors, the pyrazine-2-geranyl formate and pyrazine-2-formic acid-beta-ionol ester prepared by the method provided by the invention can significantly increase the adding amount in cigarettes, are applied as a tobacco fragrance enhancer in cigarettes, can reduce cigarette irritation and miscellaneous gas, and can improve the mellow sense and comfort of cigarette smoke.

The invention provides a spiro[cyclopropane-1, 2'-indene]-1', 3'-diketone derivative and a synthesis method thereof, and belongs to the technical field of organic synthesis of medical intermediates. The method comprises the following steps: adding a proper solvent and a proper alkali into a container filled with a substituted 2-ethylidene-1H-indene-1, 3 (2H)-diketone compound and a substituted sulfur ylide compound, stirring at a proper reaction temperature, filtering after the reaction is finished, adding water or a saturated salt aqueous solution into the filtrate, extracting with an organic solvent, carrying out drying, carrying out reduced pressure distillation concentration to remove the solvent, and carrying out column chromatography separation on the crude product to obtain the target product spiro[cyclopropane-1, 2'-indene]-1', 3'-diketone derivative.The method has the advantages of being efficient in reaction, convenient and rapid, wide in substrate adaptability, high in diastereoselectivity, high in yield and the like and has good industrial application prospects.