The new 7-(.alpha.,.alpha.-disubstituted-acetamido)-3-substituted-3-cephem-4-carbo xylic acid of the present invention is represented by the following formula: ##STR1## wherein R.sup.1 is hydrogen, halogen, hydroxy, nitro, lower alkoxy or acylamino, R.sup.2 is hydrogen or acyl and R.sup.3 is lower alkanoyloxy, carbamoyloxy which may have lower alkyl, aryl or protective group for amino, or a heterocyclicthio which may have lower alkyl, aryl or protective group for amino, or a hetero- which may have lower alkyl.
本发明的新7-(.alpha.,.alpha.-二取代-乙酰胺基)-3-取代-3-头孢-4-
羧酸的
化学式如下所示:##STR1##其中R.sup.1为氢、卤素、羟基、硝基、低烷氧基或酰
氨基,R.sup.2为氢或酰基,R.sup.3为低烷酰氧基、
氨基甲酰氧基,可能具有低烷基、芳基或
氨基的保护基,或可能具有低烷基、芳基或
氨基的杂环
硫基,或可能具有低烷基的杂环基。