Compounds of the formula [I] ##STR1## in which R.sup.1 is hydroxy, a protected hydroxy or lower alkoxy group, R.sup.2 is carboxy or an easily eliminable esterified carboxy group and R.sup.3 is pyridyl, and pharmaceutically acceptable salts thereof, having antimicrobial and .beta.-lactamase inhibiting properties, and pharmaceutical compositions containing the same.
化合物的公式为[I] ##STR1## 其中R.sup.1是羟基、保护羟基或低烷氧基,R.sup.2是羧基或易于消除的酯化羧基,R.sup.3是
吡啶基,以及其药学上可接受的盐,具有抗微
生物和β-内酰胺酶抑制作用,以及含有它们的制药组合物。