Novel cephem derivatives represented by the general formula ##STR1## in which the Acyl substituent is a group of the formula ##STR2## wherein Ar is a lipophilic optionally substituted phenyl, naphthyl or pyridyl group; R.sup.1 represents either the residue of a heterocyclic amino acid or a C.sub.2 -C.sub.10 alkyl group substituted by both a carboxyl group and a group of the formula --NR.sup.9 R.sup.10 or ##STR3## in which R.sup.9 and R.sup.10 are each independently hydrogen or C.sub.1 -C.sub.6 alkyl, said C.sub.2 -C.sub.10 alkyl group being optionally interrupted by one or more nitrogen atoms or carbonyl groups, and R.sup.2 and R.sup.3 are each independently hydrogen, alkyl or aminoalkyl are gram-positive antibacterial agents, especially useful in the treatment of diseases caused by methicillin-resistant Staphylococcus aureus (also referred to below as MRSA or methicillin-resistant S. aureus).
以通式##STR1##表示的新型
头孢菌素衍
生物,其中酰基取代物是通式##STR2##中的一个基团,其中Ar是一个亲脂性可选择取代的苯基、
萘基或
吡啶基;R.sup.1代表杂环
氨基酸残基或被羧基和通式--NR.sup.9 R.sup.10或##STR3##中的一个基团取代的C.sub.2 -C.sub.10烷基基团,其中R.sup.9和R.sup.10各自独立地是氢或C.sub.1 -C.sub.6烷基,所述C.sub.2 -C.sub.10烷基基团可选择地被一个或多个氮原子或羰基所中断,且R.sup.2和R.sup.3各自独立地是氢、烷基或
氨基烷基,是革兰氏阳性抗菌剂,特别适用于治疗由耐甲氧苄
青霉素金黄色葡萄球菌(也称为MRSA或耐甲氧苄
青霉素金黄色葡萄球菌)引起的疾病。