| 摘要 |
NEW MATERIAL:A compound of formulaI[R1 is formula II and III; R2 is formula IV (R3 is Cl, NO2, alkoxy), -OR4 (R4 is 1-4C alkyl), -OCH2OR4]. EXAMPLE:4-Chlorophenyl 7-(thiophene-2-acetamide)cephalosporanate. USE:An antibacterial that develops antibacterial activity, only when it is absorbed in bodies, thus causing no microbism substitue. PREPARATION:For example, the reaction of 7-aminocephalosporanic acid of formula V or its sodium salt with thiophene-2-acetyl chloride is carried out in water-acetone mixed solvent in the presence of an alkali metal. Then, the reaction with 4-chlorophenol follows the above reaction, in the presence of N,N- dicyclohexylcabodiimide in a solvent such as tetrahydrofuran to give the compound of formulaI. |
