Novel cephem compounds of the formula; ##STR1## wherein R.sup.1 represents amino or hydroxyl group which may be protected, R.sup.2 represents amino or hydroxyl group or a group convertible into these groups, R.sup.3 represents hydrogen or methoxy group or a group convertible into methoxy group, R.sup.4 represents hydrogen or a residue of a nucleophilic compound and R.sup.8 represents hydrogen or a halogen, or a pharmaceutically acceptable salt or ester thereof, have strong antibiotic properties against a wide variety of microorganisms including gram-positive bacteria as well as gram-negative ones, especially by oral administration and can be used as therapeutic agent for various bacterial infections of animals including human beings.
化合物的式子为:##STR1## 其中,R.sup.1代表
氨基或羟基,可以被保护;R.sup.2代表
氨基或羟基,或者是可转化为这些基团的基团;R.sup.3代表氢或甲氧基,或者是可转化为甲氧基的基团;R.sup.4代表氢或亲核化合物的残基;R.sup.8代表氢或卤素,或其药学上可接受的盐或酯。这些化合物对包括革兰氏阳性细菌和革兰氏阴性细菌在内的各种微
生物具有强大的抗生素作用,特别是通过口服给药,并可用作动物包括人类的各种细菌感染的治疗剂。