- Preparation method suitable for industrial production for high-yield high-quality cefotiam hydrochloride
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The invention relates to a preparation method suitable for industrial production for high-yield high-quality cefotiam hydrochloride. The method comprises the following steps that (1), methylene dichloride is taken as a solvent, a one-pot method is adopted, ATA,HCl and methylsulfonyl chloride generate a first intermediate in the form of acid anhydride, and then the acid anhydride liquid directly reacts with 7-aminocephalosporanic acid (7-ACA) to generate a second intermediate under the catalysis of organic alkali; (2) acetonitrile is taken as a solvent, the second intermediate reacts with 1-(2-dimethylamine ethyl)-5-sulfydryl-1,2,3,4-tetramidazole (DMMT) in the presence of boron trifluoride acetonitrile complex to obtain crude cefotiam hydrochloride, and then the cefotiam hydrochloride is obtained through rectification. The high-yield high-quality preparation method suitable for the industrial production for the cefotiam hydrochloride has the advantages that the first intermediate and the second intermediate are synthesized, and signal solvents are used separately when the crude cefotiam hydrochloride and the finished cefotiam hydrochloride are prepared so as to facilitate recycle and reuse; the steps are simple in operation, the product conversion rate is high, the impurities are small, the production cost is low, and the method is suitable for the industrial production of thehigh-quality cefotiam hydrochloride.
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- Method for the acylation of the 7-amino group of the cephalosporanic ring
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A method for the acylation of the 7-amino group of the cephalosporanic ring, according to which a 7-ACA amino thiazolyl protected adduct is prepared by acylating said amino group by an aminothiazolyl acetic acid whose amino group has been protected by a phenyl acetyl or a phenoxy acetyl group, the amino group being then deprotected by aqueous hydrolysis in the presence of penicillin G amidase or respectively penicillin V amidase.
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- A new cephalosporin. SCE-963: 7-[2-(2-aminothiazol-4-yl)-acetamido]-3- [[[1-(2-dimethylaminoethyl)-1h-tetrazol-5-yl]-thio]methyl]ceph-3-em-4-carboxylic acid. Chemistry and structure-activity relationships
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The synthesis and the in vitro and in vivo antimicrobial activities of a series of 7-[2-(2-aminothiazol-4-yl)acetamido]cephalosporins (1) having varied 3-substituents, such as methyl, hydroxymethyl, acetoxymethyl, pyridiniomethyl and heterocyclicthiomethyls, are described. The derivates having five membered heterocyclicthiomethyls exhibited strong inhibitory activities against Gram-negative organisms including some strains od Escherichia coli and Proteus morganii which are insensitive to cefazolin and cephaloridine. Pronounced activities were noted with 7-[2-(2-aminothiazol-4-yl)-acetamido]-3-[[[1-(2-dimethylaminoethyl)-1H-tetra zol-5-yl]thio]methyl]ceph-3-em-4-carboxylic acid (1y;SCE-963).
- Numata,Minamida,Yamaoka,Shiraishi,Miyawaki,Akimoto,Naito,Kida
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p. 1262 - 1271
(2007/10/09)
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- 7-Amino-thiazolyl acetamido cephalosporanic acids
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Novel 7-amino-thiazolyl-acetamido-cephalosporanic acid compounds of the formula STR1 wherein R is selected from the group consisting of hydrogen and a group easily removable by acid hydrolysis or hydrogenolysis, R1 is selected from the group consisting of alkyl of 1 to 4 carbon atoms, a 5 member heterocyclic ring and a 5 member heterocyclic ring containing a ketone group and A is selected from the group consisting of hydrogen, alkali metal and equivalents of alkaline earth metals, magnesium and organic amine having antibiotic activity against gram negative and gram positive bacteria and their preparation and novel intermediates therefore. STATE OF THE ART French Pat. No. 2,255,077 of Takeda describes antibacterial cephalosporins having a different substitutent in the 3-position.
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