12 New cephalosporines containing a pyrrole cycle in the N-acyl chain have been synthesized based on N-acylation of 7-ACA or of its 3'-analogues via the mixed anhydrides of substituted pyrrole carboxylic acids, and following two types of procedure. Confirming 1H NMR and IR data are represented. The preliminary microbiological tests in vitro show significant antibacterial activity in some cases compared with that of cefalexin. Some common structure-activity relationships have been observed.