A compound of the formula: ##STR1## in which R.sup.1 is carboxy or protected carboxy, R.sup.2 is 1-hydroxyethyl, R.sup.3 is methyl, R.sup.4 is optionally substituted pyridyl(lower)alkyl, optionally N-substituted 2-oxopiperazin-1-yl-(lower)alkyl, optionally substituted imidazol-1-yl(C.sub.2 -C.sub.3)alkyl, optionally substituted imidazol-5-yl-(lower)alkyl, optionally substituted imidazol-2-yl-(lower)alkyl, optionally substituted pyrazol-4-(or 5-)yl(lower)alkyl, optionally substituted pyrazol-1-ylethyl, optionally substituted triazolyl(lower)alkyl, optionally substituted pyrimidinyl(lower)alkyl, optionally substituted dihydropyrimidinyl(lower)alkyl, or optionally substituted (2,3-dihydroimidazo-[1,2-b]pyrazol-1-yl)ethyl, and R.sup.5 is hydrogen or imino-protective group, and pharmaceutically acceptable salts thereof, which have antimicrobial activity.
化合物的式子为:##STR1## 其中R.sup.1是羧基或保护羧基,R.sup.2是1-羟乙基,R.sup.3是甲基,R.sup.4是可选择的取代的
吡啶基(较低)烷基,可选择的N-取代的2-氧代
哌嗪-1-基-(较低)烷基,可选择的取代的
咪唑-1-基(C.sub.2-C.sub.3)烷基,可选择的取代的
咪唑-5-基-(较低)烷基,可选择的取代的
咪唑-2-基-(较低)烷基,可选择的取代的
吡唑-4-(或5-)基-(较低)烷基,可选择的取代的
吡唑-1-基乙基,可选择的取代的三唑基(较低)烷基,可选择的取代的
嘧啶基(较低)烷基,可选择的取代的二氢
嘧啶基(较低)烷基,或可选择的取代的(2,3-二氢
咪唑-[1,2-b]
吡唑-1-基)乙基,R.sup.5是氢或亚
氨基保护基,以及其药学上可接受的盐,具有抗微
生物活性。