7-Acylamino-3-substituted-3-cephem-4-carboxylic acids, processes for their preparation and pharmaceutical compositions containing them.

摘要

Cephalosporins with the formula
<Chemistry id="chema01" num="0001"><Image id="ia01" he="17" wi="72" file="IMGA0001.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>in which R represents various acyl substituents;
<UnorderedLists id="ula01" listStyle="none"><ListItem>n represents 24, preferably 2,</ListItem><ListItem>n' represents 1-4, preferably 1,</ListItem><ListItem>R' represents hydrogen or lower alkyl from one to four carbons, show antibacterial activity.</ListItem></UnorderedLists>

They can be prepared by reacting the corresponding 3-acetoxy- methyl cephalosporin with the appropriate carboxyalkylamino-alkyltetrazolethione. The tet- razolethiones used as intermediates also form part of the invention.