| 摘要 |
PURPOSE:To obtain an ester useful as an intermediate for synthesizing various kinds of cephalosporins, by reacting a liberated carboxyl group-containing penicillin, cephalosporin or its derivative with an alcohol in the presence of a base and cyanuric chloride. CONSTITUTION:A liberated carboxyl group-containing penicillin or its derivative (a compound containing acylamide, alkyl, etc. at 6-position and carboxy at 3a- position, etc.), or cephalosporin or its derivative (a compound containing a side chain of acyl amide at 7-position, unsubstituted or nucleophilic group-substituted methyl at 3-position, and carboxy at 4-and other position) is reacted with an alcohol in the presence of a base such as a trialkylamine, pyridine, etc. and cyanuric chloride. The reaction is carried out using 0.5-1.5mol cyanuric chloride, 3-8mol base, and >=1mol alcohol at -35 deg.C- room temperature preferably in an inert solvent to give the desired compound. |
