A compound, comprising: an Fe(III)-binding and/or Fe(III)-bound siderophore; one or more optional linker covalently bound to the siderophore; and daptomycin covalently bound to the linker, or, if no linker is present, then to the siderophore; or pharmaceutically acceptable salt or solvate thereof.

A compound, comprising: an Fe(III)-binding and/or Fe(III)-bound siderophore; one or more optional linker covalently bound to the siderophore; and daptomycin covalently bound to the linker, or, if no linker is present, then to the siderophore; or pharmaceutically acceptable salt or solvate thereof.

Disclosed herein are novel and inventive methods for preparing intermediates in the synthesis of C3-substituted cephalosporins. One preferred C3-substituted cephalosporin of clinical interest is Cefovecin. Accordingly, the present invention provides for methods of preparing reactive halogen intermediates for use in the synthesis of C3-substituted cephalosporins, such as Cefovecin. In the case of Cefovecin the reactive intermediates are of the formula:

##STR00001##

A compound, comprising: an Fe(III)-binding and/or Fe(III)-bound siderophore; one or more optional linker covalently bound to the siderophore; and daptomycin covalently bound to the linker, or, if no linker is present, then to the siderophore; or pharmaceutically acceptable salt or solvate thereof.