| Even with the relatively large number and diversity of chelating agents currently available, new chelators are needed for applications in many areas of life sciences. Highly stable complexes are often used as contrast agents in magnetic resonance imaging (MRI).; The design and synthesis of new ligands is presented. Molecules with known biological activity were chosen to be conjugated with chelators. The new DTPA-bis-(2(2-[2-[2-carboxymethyl-1H-benz[de]isoquinolin-1,3(2 H)-dion-6-yl]aminoethoxy]ethoxy)ethyl) amide ligand was obtained from 6-(2-[2-[2-aininoethoxy]ethoxy]ethyl) amino-2-carboxymethyl-amino-1 H-benz[de]isoquinolin-1,3(2H)-dione and DTPA dianhydride.; Cholic acid used as performylated cholic acid chloride or N-succinimydyl ester was coupled to tris(carboxyethyl[ethoxymethyl])aminomethane and an amino-bifunctional chelating agent (BFCA) derived from DTPA to give the new conjugates.; Attempts to replace the amide bonds with more reactive ester bonds by employing hydroxy-containing BFCA's failed, mainly due to lack of selectivity of breaking the formyl protecting groups vs. the internal ester bond. |
