.beta.-Lactam antibiotics of formula (I) or a salt thereof, wherein R.sup.1 is hydrogen, methoxy or formamido; R.sup.2 is an acyl group; CO.sub.2 R.sup.3 is a carboxy group or a carboxylate anion, or R.sup.3 is a readily removable carboxy protecting group; R.sup.4 represents up to four substituents; X is S, SO, SO.sub.2, O or CH.sub.2 ; m is 1 or 2; and n is 0, useful in the treatment of bacterial infections. ##STR1##
公式(I)或其盐的.beta.-内
酰胺类
抗生素,其中R.sup.1是
氢,甲
氧基或甲
酰胺基;R.sup.2是酰基;CO.sub.2 R.sup.3是羧基或
羧酸盐离子,或R.sup.3是易于去除的羧保护基;R.sup.4代表多达四个取代基;X是S,SO,SO.sub.2,O或CH.sub.2;m为1或2;n为0,有用于治疗细菌感染。##
STR1##