<unk>  is a beta-lactam antibiotic that is part of the aminopenicillin family. It is a prodrug and it has no antibacterial activity itself, but quickly splits of acetone in the human body to form ampicillin,which is active against a variety of bacteria.
Hetacillin
Plicamycin
Piperacillin
Oxacillin
Piperacillin sodium
Vancomycin 
Carbenicillin
Dicloxacillin