Several 2-aminotetralones were identified as novel inhibitors of the bacterial enzymes MurA and MurZ. A number of these inhibitors demonstrated antibacterial activity against Staphylococcus aureus and Escherichia coli with MICs in the range 8-128 microg/ml. Based on structure-activity relationships we propose that the alpha-aminoketone functionality is responsible for the inhibitory activity and evidence is provided to support a covalent mode of action involving the C115 thiol group of MurA/MurZ.