PURPOSE: To obtain the titled pharmaceutical preparation having improved oral absorption by blending a slightly orally absorbable cephalosporin type antibiotic with a quaternary ammonium salt.CONSTITUTION: A slightly orally absorbable cephalosporin type antibiotic (e.g. cefmetazole cephalothin cefazolin cefuroxime etc.) is blended with one or more quaternary ammonium salts such as a methylammonium salt (e.g. cetyltrimethylammonium bromide) alkylmethylbenzylammonium salt (e.g. stearyldimethylbenz...

PURPOSE: To obtain an antimicrobial agent Cefmetazole etc. readily without using an unstable raw material by cyanomethylating a novel cephem compound.CONSTITUTION: A 7.beta.-mercaptoacetamido-7.alpha.-methoxy-3-cephem compound of formula I (R(sup 1) is a group which will not participate in the reaction; R(sup 2) is carboxyl or protected carboxyl) is reacted with a novel compound of the formula NCCH(sub 2)X (X is halogen etc.) in the presence of a base and the protecting group is removed when R(s...