The compounds of the present invention comprise a tropane compound or ligand that selectively binds to tropane recognition sites, e.g., neuron transporters such as the DAT. The tropane ligand is radiolabeled with a radioactive technetium or rhenium by a chelating ligand which is attached to the tropane ligand by a linker. Tropane compounds or ligands useful in the pratice of the present invention can generally be represented by formula II where R1 and R2 are defined as above and where R1 can also be substituted at the C4 position of the tropane ring: Any tropane compound of the general formula II is useful in the present invention so long as it binds to DAT. Useful tropane analogs have a 3 alpha -group, i.e., are of the boat configuration. Intermediates for the synthesis of the radiolabeled tropanes are claimed.
