- A process for the preparation of cefuroxime axetil (by machine translation)
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The invention discloses a preparation method of cefuroxime axetil. The method comprises the following steps: completely dissolving cefuroxime acid in dimethylformamide, and carrying out esterification reaction with 1-bromethylacetate under the catalytic action of cupric chloride; and hydrolyzing with ethyl acetate and sodium chloride solution, extracting, carrying out vacuum distillation, crystallizing with cyclohexane, carrying out vacuum filtration, and drying to obtain high-purity cefuroxime axetil. The cupric chloride, which has the advantages of no toxicity, no harm and high catalytic efficiency, is preferably used as the catalyst; the cyclohexane for crystallization is easy to recover and reutilize, thereby lowering the production cost; and meanwhile, the method has the advantages of mild and controllable reaction conditions, short production cycle and lower energy consumption, and is suitable for industrial production.
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Paragraph 0055-0058
(2016/10/10)
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- Photoisomerization kinetics of cefuroxime axetil and related compounds
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The photoisomerization kinetics of aqueous solutions of cefuroxime axetil under irradiation at 254 nm was investigated by HPLC. The overall degradation is the result of a competition between the isomerization of the alkoxyimino group and the photolysis of the β-lactam ring. Cefuroxime axetil exists as a mixture of two diastereomers which are shown to react at different rates. This is true not only for the photoisomerization step but also for ground- state hydrolysis in alkaline conditions. Photoisomerization of the alkoxyimino group is also observed for the anti isomer of cefuroxime axetil and for some of its degradation products. The quantum yields for all these photoisomerizations are always lower than 1%, which explains the relative importance of the photolysis step. A stationary syn to anti ratio of 1 is measured for cefuroxime axetil and of 2.1 for cefuroxime. From this and previous studies, it appears that cefuroxime axetil is the most sensitive under irradiation at 254 nm when compared to other antibiotics bearing the alkoxyimino group. Aztreonam is the most stable followed by cefotaxime, cefuroxime, and cefuroxime axetil.
- Fabre,Ibork,Lerner
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p. 553 - 558
(2007/10/02)
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- Cephalosporin antibiotics
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The invention provides novel antibiotic cefuroxime esters of the formula STR1 (wherein R1 is a primary or secondary alkyl group containing 1 to 4 carbon atoms and R2 is a primary or secondary alkyl group containing 1 to 6 carbon atoms provided that at least one of the groups R1 and R2 is methyl). These compounds are useful as orally administrable broad spectrum antibiotics.
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- Process for the preparation of cephalosporin compounds
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A process for the preparation of a 3-carbamoyloxymethyl cephalosporin compound which comprises hydrolyzing a 3-phosphonocarbamoyloxymethyl cephalosporin compound. The hydrolysis is preferably effected at a pH in the range of pH3 to 4, for example using aqueous sodium hydrogen carbonate.
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- Process for the preparation of cephalosporin compounds
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A process for the preparation of cephalosporins having a phosphonocarbamoyloxymethyl group at the 3-position by reacting a cephalosporin having at the 3-position a group STR1 (wherein R4 and R5 are independently alkyl, aralkyl, alicyclic or aryl groups or together form a divalent group) with a compound of formula STR2 (wherein R6, R7 and R8 are independently alkyl, aralkyl, alicyclic or aryl groups or any two of R6, R7 and R8 together form a divalent group, and X is halogen) followed by hydrolysis. The 3-phosphonocarbamoyloxymethyl cephalosporin products of the process exhibit antibiotic activity, and if desired may be readily converted to 3-carbamoyloxymethyl cephalosporins which themselves show antibiotic activity.
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