| 摘要 |
<p>NEW MATERIAL:A compound shown by the formulaI(R1 is H, alkyl, phenyl, benzyl, furyl, etc.; R2 is H, acetoxy, carbamoyloxy, etc.; R3 is H or carboxyl-protecting group) and its salt. EXAMPLE:7beta- ( D-3-Cyanomethylthio-2-methylpropionamido ) -3-acetoxymethyl-3- cephem-4-carboxylic acid. USE:An antibacterial agent. Effective against Gram-positive and Gram-negative bacteria. PROCESS:A 2-methyl-3-thiopropionic acid derivative shown by the formula II or its reactive derivative at its carboxyl group (e.g., acid halide, anhydride of mixed acids, active ester, etc.) is reacted with a 7beta-aminocephalosporanic acid derivative shown by the formula III, to give a compound shown by the formulaI. If necessary, the carboxyl-protecting group is removed, and the compound is converted into its salt.</p> |
