RADIOACTIVE TRANSMISSION METAL-IMIDO-HETERODIPHOSPHINK COMPLEMENTS; THEIR MANUFACTURE AND RADIOPHARMAZEUTIC SUMMARIES

摘要

The present invention provides radioactive metal heterocomplexes of formula (I): Ä(Me=N-R)L1L2Ü+Z- wherein Me, R, L1 L2 and Z- have the meanings indicated in the description. The complexes include a trivalent radioactive metal-imido group, typically a technetium- or rhenium-imido group, strongly stabilized by the presence of an ancillary tridentate hetero-diphosphine ligand L1, which allows the formation of substitution-inert Ä(Me=N-R)L1Ü moieties. Such moieties are fixed in an intermediate Ä(Me=N-R)Y2L1)Ü+ compound which contains two labile, cis-positioned, Y ligands, where Y is preferably an halide group. The latter are easily replaced by a bidentate ligand L2 to give the final Ä(Me=N-R)L1L2Ü+Z- heterocomplexes. The complexes of the invention are useful for the preparation of radiopharmaceuticals: in fact, a bioactive fragment which confers biological target-seeking properties can be introduced either on the L2 framework or the imido R group.