- Preparation method of high-optical-purity 2S-(+)-flurbiprofen axetil
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The invention belongs to the technical field of medicine synthesis, and particularly relates to a preparation method of high-optical-purity 2S (+) flurbiprofen axetil, which comprises the following steps: (1) reacting 2S (+) flurbiprofen with 1-bromoethyl acetate under the actions of inorganic alkali, an organic solvent and a phase transfer catalyst, and carrying out suction filtration, washing, drying and vacuum concentration to obtain an oily crude product; and performing column chromatography purification on the oily crude product to obtain a pure product. The product yield reaches 90% or above, the optical purity reaches 99.9% or above, and the product racemization problem in the preparation process is effectively solved.
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Paragraph 0027; 0028
(2021/02/06)
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- Preparation method of 1-bromoethyl acetate
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The invention discloses a preparation method of 1-bromoethyl acetate. The preparation method comprises the steps of carrying out addition reaction by virtue of vinyl acetate and hydrobromic acid in the presence of strong acid cation resin and an organic acid catalyst at room temperature, washing, extracting and drying reactants, and carrying out reduced pressure distillation, so as to obtain 1-bromoethyl acetate. The purity of prepared 1-bromoethyl acetate is over 97%, and the yield is over 78.8%. The preparation method has the advantages that the raw material cost of the synthetic method is low, the reaction condition is mild, the yield is high, the post-treatment is simple and convenient, and the preparation method has industrial application values.
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Paragraph 0024-0043
(2019/01/22)
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- Preparation method of 1-bromoethyl acetate
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The invention belongs to the field of chemical synthesis, and relates to a preparation method of 1-bromoethyl acetate. According to the method, nano Fe3O4 is used as a catalyst, and the target productis generated by enabling silicon tetrabromide and vinyl acetate to react in a water solution. The process conditions of the method are mild and easy to control, the catalyst is high in activity and easy to recover, and product yield and purity are high.
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Paragraph 0052-0053; 0056-0057; 0061-0062; 0065-0074
(2018/09/08)
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- Crystalline cefuroxime axetil preparation method
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The invention relates to a crystalline cefuroxime axetil preparation method, which comprises: 1) carrying out a reaction on paraldehyde and acetyl bromide at a temperature of -10-10 DEG C under the action of a catalyst to obtain 1-bromoethyl acetate; 2) adding cefuroxime acid and a catalyst to the mixed solution of an organic solvent and water, adjusting the temperature to -20-5 DEG C, adding the1-bromoethyl acetate prepared in the step 1) to the mixed solution in a dropwise manner to obtain the crystalline cefuroxime axetil. According to the present invention, the method improves the traditional process, simplifies the process, improves the product quality, does not use the extraction solvent dichloromethane, greatly reduce the production cost, and improves the reaction efficiency and the purity of the final product.
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Paragraph 0048; 0050; 0051; 0054-0055; 0058-0069
(2018/10/19)
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- Synthesis and biological evaluation of orally active hypolipidemic agents
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A series of novel fenofibric acid ester prodrugs 1c-1h were synthesized and evaluated with the aim of obtaining potent hypolipidemic agents. Prodrugs 1c and 1d exhibited potent hypochlolesterolemic activity, lowering the mice plasma triglyceride level up to 47% in Swiss albino mice after oral administration of 50 mg/kg/day for 8 days. Fenofibric acid ester prodrugs 1c-1h were found lipophilic like fenofibrate (1b), indicated by partition coefficients measured in octanol-buffer system at pH 7.4. On the basis of in vivo studies, prodrugs 1c and 1d emerged as potent hypolipidemic agents.
- Bandgar, Babasaheb P.,Sarangdhar, Rajendra J.,Khan, Fruthous,Mookkan, Jeyamurugan,Shetty, Pranesha,Singh, Gajendra
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experimental part
p. 5915 - 5926
(2011/10/08)
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