Derivatives of cephalosporins, their process of separation and antibiotic drugs containing the said derivatives

摘要

The present invention relates to cephalosporins having the formula: ##STR1## in which COOA is an acidic radical, salt or ester, and R.sub.1 represents a group: ##STR2## in which R.sub.A and R.sub.B are H or alkyl or together form a cycloalkyl with the carbon to which they are bonded, R. sub.2 and R.sub.3 are H, alkyl or alkenyl, R.sub.4 and R.sub.5 are H, alkyl or alkenyl or together form a ring to the nitrogen atom with which they are bonded. This invention also relates to a process for the preparation of these compounds and to drugs containing them.