S-(-)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-iodo-2,3-dimethoxybenzamide (proposed generic name, epidepride) is a very potent dopamine D2 antagonist. It was synthesized by five steps from 3-methoxysalicylic acid. [131I]epidepride was obtained in 97.3% radiochemical yields from the corresponding 5-(tributyltin) derivative using hydrogen peroxide as the oxidant. The aryltin precursor was prepared from non-labelled epidepride by palladium-catalyzed stannylation using bis(tri-n-butyltin) in triethylamine. [131I]epidepride was stable under 4℃, and partition coefficient was 72.3 at pH 7.40. The biodistribution study in rats exihibited high localization in the striatum of the brain with the striatum/cerebellum ratio reaching 237/1 at 320 min postinjection. All these results suggest that [131I]epidepride may be used widely as a useful dopamine D2 receptor imaging agent for SPECT. It was synthesized by five (5-iodo-2,3-dimethoxybenzamide (proposed generic name, epidepride) is a very potent dopamine D2 antagonist steps from 3-methoxysalicylic acid. [131 I] epidepride was obtained in 97.3% radiochemical yields from the corresponding 5- (tributyltin) derivative using hydrogen peroxide as the oxidant. The aryltin precursor was prepared from non-labelled epidepride by palladium-catalyzed stannylation using [131I] epidepride was stable at 4 ° C and partition coefficient was 72.3 at pH 7.40. The biodistribution study in rats exihibited high localization in the striatum of the brain with the striatum / cerebellum ratio reaching 237/1 at 320 min postinjection. All these results suggest that [131I] epidepride may be used widely as a useful dopamine D2 receptor imaging agent for SPECT.