Novel cephalosporins which has attached to the exomethylene group at the 3-position of the cephem ring a substituted or unsubstituted aryl, acylamino, aromatic heterocyclic, triazolyl or tetrazolyl group, said aromatic heterocyclic group being attached through a carbon-carbon bond and said triazolyl or tetrazolyl group being attached through a carbon-nitrogen bond, and has the following group attached to the amino group at the 7-position: ##STR1## wherein A represents a group of the formula, --CH.sub.2 -- or a group of the formula ##STR2## in which R.sup.5 represents a hydrogen atom or an alkyl group, and the bond.about.represents syn or anti isomer or their mixture; R.sup.3 represents a hydrogen or halogen atom; and R.sup.4 represents a hydrogen atom or an amino group which may be protected or substituted. These cephalosporins have a broad antibacterial spectrum, are stable against .beta.-lactamase produced by bacteria, have a low toxicity, and are well absorbed when administered orally or parenterally.
具有以下结构的新型
头孢菌素,该结构在头孢环的3位上连接了取代或未取代的芳基,酰基
氨基,芳香族杂环,三唑基或
四唑基基团的外甲基烯基:其中所述的芳香族杂环基团通过碳-碳键连接,所述的三唑基或
四唑基基团通过碳-氮键连接,并且在7位上的
氨基团上连接有以下基团:##STR1## 其中A代表以下公式的基团,--CH.sub.2--或以下公式的基团:##STR2## 其中R.sup.5代表氢原子或烷基,而bond.about.代表syn或anti异构体或其混合物;R.sup.3代表氢或卤素原子;R.sup.4代表氢原子或可能被保护或取代的
氨基团。这些
头孢菌素具有广谱抗菌谱,对细菌产生的β-内酰胺酶稳定,毒性低,并且口服或经静脉注射时吸收良好。