Bifunctional chelating agents

A bifunctional chelating agent of the formula (I):

• wherein:
• -M- is
• Q1, Q2 and Q4 are independently H or R;
• Q5 is H, R or R1″;
• Q6 is H or R1″;
• Q7 is H or R;
• A1 and A2 form together with the atoms to which they are attached a C6-C10-aryl, C6—C1-10-heteroaryl, C3-C5-cycloalkyl, C7-C10-cycloalkyl or C3-C10-heterocyclyl group;
• R is —C(O)-L,
• —(CHR2)pCOR3 or —(CHR2)pPO2R4R5;
• Q3 is H, —(CHR2)wCOR3 or —(CHR2)wPO2R4R5;
• R1, R1′ and R1″ are independently
• each R2 is independently hydrogen;
• C1-C4 alkyl or (C1-C2alkyl)phenyl;
• each R3, R4 and R5 are independently OH, an —O-protecting group or a leaving group;
• R6 is H;
• OH;
• an alkyl-LG or alkoxy-LG, wherein LG is a leaving group;
• a boronate ester or a leaving group;
• X and Y are each independently hydrogen or may be taken with an adjacent X and Y to form an additional carbon—carbon bond;
• Z1 and Z2 are independently CH or N;
• m is an integer from 0 to 10 inclusive;
• n is 0 or 1;
• p is 1 or 2;
• r is 0 or 1;
• w is 0 or 1;
• z is 1 or 2;
• L is a linker/spacer group covalently bonded to, and replacing one hydrogen atom of the carbon atom to which it is joined, said linker/spacer group being represented by the formula (II):
• wherein:
• s is an integer of 0 or 1;
• t is an integer of 0 to 20 inclusive;
• R7, R8 and R9 are independently H;
• an electrophilic, nucleophilic or electron-rich moiety that allows for covalent attachment to a carrier comprising a biotargeting group, a lipophilic moiety or a biosensor;
• a protected form or a precursor of the electrophilic, nucleophilic or electron-rich moiety;
• or a synthetic linker having an electrophilic, nucleophilic or electron-rich moiety that allows for covalent attachment to the carrier comprising a biotargeting group, a lipophilic moiety or a biosensor, or a protected form or a precursor of the electrophilic, nucleophilic or electron-rich moiety of the synthetic linker, and
• Cyc represents a cyclic aliphatic moiety, aromatic moiety, aliphatic heterocyclic moiety, or aromatic heterocyclic moiety, each of said moieties optionally substituted with one or more groups, which do not interfere with binding to a carrier comprising a biotargeting group, a lipophilic moiety or a biosensor;
• or a pharmaceutically acceptable salt thereof,
• provided that the chelating agent is not 6,6′,6″,6′″-((ethane-1,2-diylbis(azanetriyl))tetrakis(methylene))tetrapicolinic acid, 6,6′-((ethane-1,2-diylbis((phosphonomethyl)azanediyl))bis(methylene))dipicolinic acid, 6,6′-((ethane-1,2-diylbis((carboxymethyl)azanediyl))bis(methylene))dipicolinic acid or 6,6′-((ethane-1,2-diylbis((pyridin-2-ylmethyl)azanediyl))bis(methylene))dipicolinic acid, and
• provided that the bifunctional chelating agent comprises at least one covalently attached moiety that allows for covalent attachment to the carrier comprising a biotargeting group, a lipophilic moiety or a biosensor.