A compound is provided, comprising: an Fe(III)-binding or an Fe(III)-bound siderophore; one or more optional linker covalently bound to the siderophore; a drug; and an Fe(III) to Fe(II) reduction triggered linker bound to the drug and the linker or, if no linker is present, then bound to the drug and the siderophore. Compositions and methods including the compound are also provided.