Synthesis and antibacterial activity of 2-oxocephalosporins

The first reported synthesis of 2-oxocephalosporin derivatives has been achieved via ozonolysis of the corresponding 2-methylenecephalosporins. The new cephalosporin derivatives showed some antibacterial activity against Gram-positive bacteria, but the 2-oxo analogue of cephalothin was much less active than cephalothin itself.