Compounds according to formula I are provided: A-L-B wherein A represents a lipophilic chelating moiety which is selective for Zn2+ ions; L is a covalent bond or a linker; and B is a vector which is either a moiety capable of interacting with one or more biological structures found in a bacterium (preferably in a bacterial cell wall), for example a penicillin-binding protein such as a metallo-β-lactamase or DD-transferase, or a moiety capable of enhancing transport of the compound across a bacterial cell membrane. A method of treating and/or preventing a bacterial infection in a human or non-human mammal employing such compounds are also provided. In such a method, the compound of formula I may be administered in combination with (either simultaneously, separately, or sequentially) a β-lactam antibiotic.