Compounds of the formula: ##STR1## wherein R.sup.1 is (C.sub.1 to C.sub.6) alkyl. R.sup.2 is carboxy or a protected carboxy group, R.sup.3 is amino or a protected amino group and A is hydroxyimino (C.sub.1 to C.sub.6) alkylene or (C.sub.1 to C.sub.6)-alkoxyimino (C.sub.1 to C.sub.6) alkylene, and pharmaceutically acceptable salt thereof, have been found to be active against various pathogenic microorganisms.
公式为:##STR1## 其中R.sup.1为(C.sub.1至C.sub.6)烷基。R.sup.2为羧基或受保护的羧基,R.sup.3为
氨基或受保护的
氨基,A为羟
肟基(C.sub.1至C.sub.6)烷基或(C.sub.1至C.sub.6)烷氧
肟基(C.sub.1至C.sub.6)烷基,以及其药学上可接受的盐,已发现对各种致病微
生物具有活性。