Process for preparation of MR contrast agents

摘要

The present invention provides a process for the preparation of an MR contrast agent, said process comprising:i) obtaining a solution in a solvent of a hydrogenatable, unsaturated substrate compound and a catalyst for the hydrogenation of said substrate compound;ii) introducing said solution in droplet form into a chamber containing hydrogen gas (H2) enriched in para-hydrogen (p-<1>H2) and/or ortho-deuterium (o-<2>H2) whereby to hydrogenate said substrate to form a hydrogenated imaging agent;iii) optionally subjecting said hydrogenated imaging agent to a magnetic field having a field strength below earth's ambient field strength;iv) optionally dissolving said imaging agent in an aqueous medium;v) optionally separating said catalyst from the solution of said imaging agent in said aqueous medium;vi) optionally separating said solvent from the solution of said imaging agent in said aqueous medium; andvii) optionally freezing the solution of said imaging agent in said aqueous medium.