A cephalosporin derivative having the formula: ##STR1## wherein R.sup.1 is a substituted amino group, X is an alkylene group, R.sup.2 is an aryl or heterocyclic group which may be substituted and R.sup.3 is a hydrogen atom, a negative charge or a residue of an ester which can form a pharmaceutically acceptable ester hydrolyzable in a living body; or a pharmaceutically acceptable salt thereof.
一种
头孢菌素衍
生物,其
化学式为: ##STR1## 其中R.sup.1是一个取代的
氨基团,X是一个烷基团,R.sup.2是一个可能被取代的芳基或杂环基团,R.sup.3是一个氢原子,一个负电荷或能够在
生物体内
水解的酯的残基,该酯可以形成一种药学上可接受的酯;或其药学上可接受的盐。