Novel rhenium complexes derived from α-tropanol as potential ligands for the dopamine transporter Original Research Article

A series of rhenium complexes was synthesized as model compounds for the corresponding radioactive technetium-99m complexes for preliminary biological investigations. In a ‘3+1’ mixed-ligand approach the tropanol molecule was linked with the metal core through a ω-mercaptoester group as monodentate ligand. Bis(thioethyl)sulphide was used as the tridentate dithiol ligand to block the remaining free coordination sites. The ω-mercaptoesters were synthesized via the trityl-protected precursors. Binding tests on the cloned human dopamine transporter revealed moderate binding affinities for some of the prepared compounds. The complexes were characterised by X-ray and the lipophilicity as well as pKa values were determined.