| abstract |
An object of the present invention is to overcome the disadvantages of known complexes, improve labeling ability at low ligand concentrations, stabilize complex structures, improve biodistribution, increase uptake into target tissues, and non-target tissues and Provided are a folic acid complex exhibiting a plurality of advantages such as good clearance from an organ, and a metal chelate complex as a radionuclide complex that can be used as a tumor imaging agent for imaging methods and radiotherapy of tumor tissue. A pharmaceutical composition comprising a folic acid complex represented by general formula I and a pharmaceutically acceptable carrier. [F is folic acid or a derivative thereof; Z 1 to Z 3 are independently of each other, C or N; S 1 to S 3 are independently of each other, a single bond or a spacer; R a , R a ′ , R b are Independently of each other, is a donor group and / or other F group; R c is optionally another F group; and n is 1 or 2] [Selection figure] None |