Process for purification of a cephalosporin derivative
申请人:——
公开号:US20030208065A1
公开(公告)日:2003-11-06
A process for the purification of cefixime via a novel tert.octylamine salt of a cefixime intermediate which may be crystalline and which may be produced in a one pot reaction from 7-amino-3-vinyl-ceph-3-em-4-carboxylic acid.
A method of improving the stability of a quaternary ammonium salt and a method of efficiently preparing the quaternary ammonium salt having improved stability.
一种提高季铵盐稳定性的方法和一种高效制备稳定性提高的季铵盐的方法。
Process For the Preparation of Cefixime
申请人:Parthasaradhi Bandi
公开号:US20080242858A1
公开(公告)日:2008-10-02
There is provided an improved process for preparing cefixime. Thus, for example, 7-amino-3-vinyl-3-cephem-4-carboxylic acid is reacted with 2-mercapto-1,3-benzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-(methoxycarbonyl)-methoxyimino acetate in tetrahydrofuran and water at 4° C. in the presence of triethylamine. The reaction mass is extracted with ethyl acetate. 7-[2-(2-Amino-4-thiazolyl)-2-(methoxycarbonylmethoxyimino)acetamido]-3-vinyl-3-cephem-4-carboxylic acid triethylamine salt present in the aqueous layer is hydrolyzed with sodium hydroxide in less than 30 minutes and aqueous hydrochloric acid is added immediately to adjust the pH to 4.8 to 5.2. Then, aqueous hydrochloric acid is added at 35° C. to adjust the pH 2.5 and cooled to crystallize cefixime trihydrate in high purity.
A method of improving the stability of a quaternary ammonium salt and a method of efficiently preparing the quaternary ammonium salt having improved stability.