Synthesis and Antibacterial Activity of 7β‐[3‐(Un)substituted‐2‐aminopropionamido]‐3‐vinylcephalosporins and Related Compounds

A series of new 7β‐[3‐(un)substituted‐alanyl]‐3‐vinylcephalosporins and some related compounds, 4a – 1 is described. They incorporate residues of proteinogenic L ‐α‐aminocarboxylic acids, their antimetabolites and enantiomers as well as a dipeptide in the 7β‐acylamido side chain. The acylation of diphenyl‐methyl 7‐amino‐3‐vinyl‐3‐cephem‐4‐carboxylate ( 2 : R 2 = DPM) with various protected α‐aminocarboxylic acids 1a – k and the dipeptide 1l is carried out using TBTU as coupling reagent. The compounds, except 4f , are active in vitro against S. aureus and S. lutea , but only 4a, 4k , and 4l inhibit some of the Gram‐negative strains.