Dendritic encapsulation of ^99mTc and ¹⁸⁸Re species

A series of different dendrons for the encapsulation of ^99mTc and ¹⁸⁸Re have been synthesised, "3+1" mixed ligand ^99mTc complexes with dendritic polyether thiols as monodendate ligands have been prepared. Challenge experiments with glutathione showed a remarkable enhancement of stability with increasing number of dendron generation. To achieve better solubility behaviour oligoethyleneoxy- and sugar-substituted dendrons are developed. In this case 2-aminobenzenethiol is introduced as chelating unit. Molecular modeling calculations point to an almost complete shielding of the radionuclide by use of second generation dendrons.