A Third Generation Potentially Bifunctional Trithiol Chelate, Its Sb(III) Complex, and Selective Chelation of Radioantimony (Sb) from Its Sn Target.

The therapeutic potential of the Meitner-Auger- and conversion-electron emitting radionuclide Sb remains unexplored because of the difficulty of incorporating it into biologically targeted compounds. To address this challenge, we report the development of Sb production from electroplated tin cyclotron targets and its complexation by a novel trithiol chelate. The chelation reaction occurs in harsh solvent conditions even in the presence of large quantities of tin, which are necessary for production on small, low energy (16 MeV) cyclotrons. The Sb-trithiol complex has high stability and can be purified by HPLC. The third generation trithiol chelate and the analogous stable Sb-trithiol compound were synthesized and characterized, including by single-crystal X-ray diffraction analyses.