| 摘要 |
<p>The present invention provides a method for the preparation of esters of 7-beta-[(Z)-(2-aminothiazol-4- yl)-2-(methoxycarbonylmethoxyimino)acetamido]-3-vinyl-3- cefeme-4-carboxylic acid for use in the preparation of cefixime, characterised in comprising <IMAGE>, Formula I <IMAGE>, Formula II <IMAGE>, Formula IV <IMAGE>, Formula V where R1 = -CHPh2 or -CH2-C6H4-OCH3 and R2 = -HCO or any other amino protective group; the dissolving of the compound of formula II in aliphatic halogenated hydrocarbons using an organic base, as described herein, in the proportion of 1:1-10 moles; the preparation of a Vilsmeier reagent of the compound of formula IV in aliphatic halogenated hydrocarbon using N,N- dimethylformamide and phosphorus oxychloride; the binding of the compound of formula II with Vilsmeier reagent to the compound of formula IV, at -10 degrees Celsius to -60 degrees Celsius, to form a compound of formula V; the isolating of said compound of formula V in DM-H2O; the dissolving of the compound of formula V in organic solvent as described herein at room temperature and, after this, the addition of thiourea and agitation of the reaction mixture at 0-25 degrees Celsius; the extraction of the reaction mass in a mixture of DM-H2O and aliphatic halogenated hydrocarbon, in the proportion of 1-10:10-1; the washing of the aliphatic halogenated hydrocarbon phase with saturated solution of alkaline chloride and, after this, drying; the isolating of the compound of formula I by concentration of the aliphatic halogenated hydrocarbon phase in vacuo.</p> |
