PROCESS FOR PRODUCING 1, 4, 7, 10-TETRAAZACYCLODODECANE-1, 4, 7, 10-TETRAACETIC ACID AND COMPLEXES THEREOF

摘要

The present invention relates to a process for producing 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA) including salts and hydrates thereof of general formula (I) from the respective cyclen. Said process further involves the use of cationic- and anionic exchange resins and solvent treatments to remove the organic and inorganic contaminants. Any cations present in the raw DOTA or other contaminants resulting from the reaction of cyclen are largely reduced in early stages of the process allowing to obtain good yields of DOTA in a purified grade and in an easier and reliable way. The present invention is thus useful for the production of DOTA, of macrocyclic compounds comprising metal ions complexes thereof and of compositions comprising said macrocyclic compounds that can be used as contrast agents for magnetic resonance imaging.