A new 2-thiohydantoin Tc-99(V) complex was prepared by the direct redu
ction of TcO4- with alkaline Na2S2O4 in the presence of an excess of t
he ligand, and characterized by spectroscopy. Reversed phase HPLC on l
ichrosorb-Rp-18 showed the complex to be pure; electrophoresis measure
ments showed it to be neutral. The complex was H2O soluble.