- Method for synthesizing ceftiofur intermediate and ceftiofur
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The invention belongs to the technical field of chemical synthesis, and concretely relates to a method for synthesizing a cefotaxime intermediate 7-amino-3-[(2-furyl-carbonyl)-thiomethyl]-3-cephem-4-carboxylic acid and ceftiofur. The method comprises the following steps: sequentially adding 7-aminocephalosporanic acid, thiofurancarboxylic acid, a solid base catalyst gamma-Al2O2-O2Na, zeolite and water into a reaction kettle, performing stirring and reacting at room temperature for 1.5-2.5 h, filtering the obtained reaction solution, adjusting the pH value of the obtained filtrate to 5.5-6.5 by using an appropriate amount of hydrochloric acid, filtering the filtrate, washing the obtained filter cake with water to obtain a white solid, and performing vacuum drying to obtain the 7-amino-3-[(2-furyl-carbonyl)-thiomethyl]-3-cephem-4-carboxylic acid. The method uses water as a solvent, so the production cost is reduced, the produced products have a high yield and a high purity, and the promotion of industrial production is benefited.
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Paragraph 0026
(2019/01/07)
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- AN IMPROVED PROCESS FOR THE PREPARATION OF CEPHALOSPORIN ANTIBIOTIC
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An improved one pot process for the preparation of Ceftiofur of the formula (I) or its salt, without isolating the intermediate compound.
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Page/Page column 4; 7; 12-14
(2008/12/05)
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- NOVEL INTERMEDIATES FOR SYNTHESIS OF CEPHALOSPORINS AND PROCESS FOR PREPARATION OF SUCH INTERMEDIATES
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A novel 4-halo-2-oxyimino-3-oxo butyric acid-N, N-dimethyl formiminium chloride chlorosulfate of formula (I) useful in the preparation of cephalosporin antibiotics, wherein X is chlorine or bromine; R is hydrogen, C1-4 alkyl group, an easily removable hydroxyl protective group, -CH2COOR5, or -C(CH3)2COOR5, wherein R5 is hydrogen or an easily hydrolysable ester group. The compound of formula (I) is prepared by reacting 4-halo-2-oxyimino-3-oxobutyric acid of formula (IV1), wherein X, R and R5 are as defined above, with N, N-dimethylformiminium chloride chlorosulphate of formula (VII), in an organic solvent at a temperature ranging from -30 °C to -15 °C. The cephalosporins that may be prepared from the intermediate include cefdinir, cefditoren pivoxil, cefepime, cefetamet pivoxil, cefixime, cefmenoxime, cefodizime, cefoselis, cefotaxime, cefpirome, cefpodoxime proxetil, cefquinome, ceftazidime, cefteram pivoxil, ceftiofur, ceftizoxime, ceftriaxone and cefuzonam.
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- Method for preparation of ceftiofur and salts thereof
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A process for preparation of ceftiofur sodium of formula (Ib) possessing high stability and having purity of more than 97% and substantially free of impurities, is disclosed. The process comprises: i) reacting cefotaxime or its salts or its esters of formula (VI) ?wherein R3 is hydrogen, an alkali or alkaline earth metal, or an easily hydrolysable ester, with thiofuroic acid, employed in a molar proportion of 1.5 to 3.0 moles per mole of compound (VI), in the presence of acetonitrile as solvent and in the presence of large excess of methanesulfonic acid, employed in molar proportions of 12 to 18 moles per mole of compound (VI), and at a temperature of between ?5° C. to 30° C. to give after necessary neutralisation of the alkali or alkaline earth metal or removal of the ester group of the 4-carboxylic acid function, wherever applicable, ceftiofur of formula (Ia), possessing high stability and having purity of more than 97% and substantially free of impurities; ii) converting the ceftiofur of formula (Ia) thus obtained to its salt with an organic amine by treating a solution of ceftiofur in a mixture of water and a water-miscible organic solvent with an organic amine, at a temperature ranging from ?10° C. to 10° C.; iii) reacting of the amine salt thus obtained with a sodium metal carrier in a mixture of water and water-miscible organic solvent and in presence of sodium hydrogen sulfite to give ceftiofur sodium of formula (Ib)
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- New method for the preparation of ceftiofur sodium and its intermediates
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The present invention relates to a new method for the preparation of Ceftiofur acid of formula (I), its pharmaceutically acceptable salt such as sodium or hydrochloride and also provides two new intermediates of formulae (V) and (VI) wherein X represents halogen atom such as chlorine or bromine and R represents p-methoxybenzyl, p-nitrobenzyl or diphenylmethyl group.
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Page/Page column 5-6
(2010/01/31)
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- Crystalline ceftiofur free acid
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Anhydrous and crystalline free acid form of the cephalosporin antiobiotic ceftiofur, processes for its manufacture, and pharmaceutical composition containing it are provided. STR1
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