A compound that has: ** Formula ** where: Z has the structure of: ** Formula ** R5 is H, COR8, C1-C6 alkyl or thiazole； R8 is OH or -NH- (alkylene-O) n-NH2； R6 is OH or H； Ar is phenyl or pyridine； R7 is C1-C6 alkyl or hydrogen； And it is selected from the group consisting of a hydroxylamine； L is a linker selected from the group consisting of -alkylene-, -alkylene-C (O) -, - (alkylene-O) n-alkylene-, - (alkylene-O) n-alkylene-C (O) -, - (alkylene-O) n- (CH2) n'-NHC (O) - (CH2) n "-C (Me) 2-SS- (CH2) n '" - NHC (O) - (alkylene-O) n '' '- alkylene-, - (alkylene-O) n-alkylene-W-, -alkylene-C (O) -W-, - (alkylene-O) n-alkylene-U-alkylene-C (O ) - and - (alkylene-O) n-alkylene-U-alkylene-； W has the structure of: ** Formula ** U has the structure of: ** Formula ** or L is absent, Y is methyl, R5 is COR8, and R8 is -NH- (alkylene-O) n-NH2； and each n, n ', n ", n'" and n " are independently integers greater than or equal to one； or a salt thereof； (ii) Formula (III), (IV), (V) or (VI): ** Formula ** where: Z has the structure of: ** Formula ** R5 is H, COR8, C1-C6 alkyl or thiazole； R8 is OH； R6 is OH or H； Ar is phenyl or pyridine； R7 is C1-C6 alkyl or hydrogen； Y and V are each selected from the group consisting of a hydroxylamine； L1, L2, L3 and L4 are each of the linkers independently selected from the group consisting of a bond, -alkylene-, - (alkylene-O) n-alkylene-J-, -alkylene'-J- (alkylene-O ) n-alkylene-, -J- (alkylene-O) n-alkylene-, - (alkylene-O) n-alkylene-J- (alkylene-O) n'-alkylene-J'-, - (alkylene-O ) n-alkylene-J-alkylene'-, -W-, -alkylene-W-, alkylene'-J- (alkylene-NMe) n-alkylene-W-, -J- (alkylene-NMe) n-alkylene- W-, -J-alkylene-NMe-alkylene'-NMe- alkylene "-W-, and -alkylene-J-alkylene'-NMe-alkylene" -NMe-alkylene "'- W-； W has the structure of: ** Formula ** each J and J 'independently have the structure of: ** Formula ** and each nyn' are independently integers greater than or equal to one； or a salt thereof.Un compuesto que tiene: **Fórmula** en
