Diazepam, which aims at benzodiazepine receptors and can be used as a
specific SPECT agent has been labeled with [I-131]2-iododiazepam (2-ID
Z) was obtained in 50% HCl medium and [I-131]2'-iododiazepam (2'-IDZ)
was prepared by the indogen method. The products were purified by pass
ing through a Dowex-1 anion-exchange column.