Macrocyclic ligands with picolinate group(s), complexes thereof and also medical uses thereof

1. A compound of general formula (X)

in which:

R 1 and R 2 represent, independently of each other, one of the following:

H, a (C 1 -C 20 )alkyl group or a (C 1 -C 20 )alkylene-(C 6 -C 10 )aryl group, wherein said alkyl, alkylene and aryl groups optionally are substituted with one or more organic acid functions;

X 1 , X 2 and X 3 represent, independently of each other, one of the following:

H, —C(O)N(Re)(Rd), a (C 1 -C 20 )alkyl, a (C 2 -C 20 )alkenyl, a (C 2 -C 20 )alkynyl and a (C 6 -C 10 )aryl, with Re and Rd being, independently of each other, H or a (C 1 -C 20 ) alkyl group, wherein said alkyl, alkenyl and alkynyl groups optionally comprise one or more heteroatoms and/or one or more (C 6 -C 10 )arylenes in their chains, and wherein said alkyl, alkenyl and alkynyl groups optionally are substituted with a (C 6 -C 10 )aryl;

wherein said alkyl, alkenyl, alkynyl and aryl groups optionally are substituted with one or more organic acid functions; and

Y 1 represents a C(O)OH group, a protected form of the C(O)OH group in which the hydrogen is replaced with an alkyl, or a group of formula (II)

in which the radicals Ri represent, independently of each other, one of the following:

H, halogen, N 3 , (C 1 -C 20 )alkyl, (C 2 -C 20 )alkenyl, (C 2 -C 20 )alkynyl and (C 6 -C 10 )aryl, wherein said alkyl, alkenyl and alkynyl groups optionally comprise one or more heteroatoms and/or one or more (C 6 -C 10 )arylenes in their chains and, wherein said alkyl, akenyl, and alkynyl groups optionally are substituted with a (C 6 -C 10 ) aryl;

wherein said alkyl, alkenyl, alkynyl and aryl groups optionally are substituted with one or more organic acid functions.

2. The compound of claim 1 , wherein X 1 , X 2 and X 3 represent, independently of each other, one of the following:

H, (C 1 -C 20 )alkyl, (C 2 -C 20 )alkenyl and (C 2 -C 20 )alkynyl, wherein said alkyl, alkenyl and alkynyl groups optionally comprise one or more heteroatoms in their chain.

3. The compound of claim 2 , wherein X 1 , X 2 and X 3 are H.

4. The compound of claim 1 , wherein the organic acid functions optionally substituting the alkyl, alkenyl, alkynyl and aryl groups of the X 1 , X 2 and X 3 are, independently of each other, one of the following:

—COOH, —SO 2 OH, —P(O)(OH) 2 and —O—P(O)(OH) 2 .

5. The compound of claim 1 , wherein R 1 and R 2 represent, independently of each other, H or (C 1 -C 20 )alkyl group.

6. The compound of claim 5 , wherein R 1 and R 2 represent H.

7. The compound of claim 1 , wherein the organic acid functions optionally substituting the alkyl, alkylene and aryl groups of R 1 and R 2 represent, independently of each other, one of the following:

—COOH, —SO 2 OH, —P(O)(OH) 2 and —O—P(O)(OH) 2 .

8. The compound of claim 1 , wherein the radicals Ri represent, independently of each other, one of the following:

H, (C 1 -C 20 )alkyl, (C 2 -C 20 )alkenyl and (C 2 -C 20 )alkynyl, wherein said alkyl, alkenyl and alkynyl groups optionally comprise one or more N, O and S heteroatoms.

9. The compound of claim 1 , wherein the radicals Ri represent, independently of each other, H or (C 2 -C 15 )alkynyl.

10. The compound of claim 1 , wherein the organic acid functions substituting the alkyl, alkenyl, alkynyl and aryl groups of the radicals Ri represent, independently of each other, one of the following:

—COOH, —SO 2 OH, —P(O)(OH) 2 and —O—P(O)(OH) 2 .

11. The compound of claim 10 , wherein the organic acid functions substituting the alkyl, alkenyl, alkynyl and aryl groups of the radicals Ri represent —COOH.

12. The compound of claim 1 , wherein the group of formula (II) is the following group:

13. The compound of claim 1 , wherein:

R 1 and R 2 represent H; and

Y 1 represents C(O)OH or the following formula:

14. A method of preparing the compound of claim 1 , the method comprising:

functionalizing a compound of general formula (IX)

by adding to the nitrogen atom of the NH group thereof a —C(R 1 )(R 2 )—Y 1 group wherein:

R 1 and R 2 represent, independently of each other, one of the following: H, a (C 1 -C 20 )alkyl group or a (C 1 -C 20 )alkylene-(C 6 -C 10 )aryl group, wherein said alkyl, alkylene and aryl groups optionally are substituted with one or more organic acid functions;

Y 1 represents a C(O)OH group, a protected form of the C(O)OH group in which the hydrogen is replaced with an alkyl, or a group of formula (II)

in which the radicals Ri represent, independently of each other, one of the following:

H, halogen, N 3 , (C 1 -C 20 )alkyl, (C 2 -C 20 )alkenyl, (C 2 -C 20 )alkynyl and (C 6 -C 10 )aryl, wherein said alkyl, alkenyl and alkynyl groups optionally comprise one or more heteroatoms and/or one or more (C 6 -C 10 )arylenes in their chains and, wherein said alkyl, akenyl, and alkynyl groups optionally are substituted with a (C 6 -C 10 )aryl;

wherein said alkyl, alkenyl, alkynyl and aryl groups optionally are substituted with one or more organic acid functions; to form the compound (X) of claim 1 .

15. The compound of claim 1 , wherein the alkyl that replaced the hydrogen of the protected form of the C(O)OH group of Y 1 is selected from the group consisting of tert-butyl and methyl.