Synthesis of some phenothiazine derivatives as potential affinity ligands for the central dopamine receptors

Article abstract of DOI:10.1111/j.2042-7158.1991.tb05442.x

Syntheses of several phenothiazine ligands as potential affinity probes for the D₁ and D₂-dopamine receptors derived from 4-(3-(10-(2-trifluoromethyl) phenothiazinyl) propyl)-1-(2-aminoethyl)-piperazine hydrochloride are described and their interactions with D₁- and D₂-dopamine receptors of the bovine caudate nucleus have been characterized. The bromoacetylamido-, maleinimido-, and isothiocyanato-derivatives expressed low selectivity and moderate affinity for both categories of dopamine receptors. 4-(3-(10-(2-Trifluoromethyl) phenothiazinyl)propyl)-1-(2-(isothiocyanatobenzoyl)ethyl)-piperazine hydrochloride did not discriminate among the two subclasses of the dopamine receptors, but showed an extremely strong irreversible binding to the D₁-receptors and thus is promising as a highly specific affinity ligand for biochemical and pharmacological studies of the D₁-dopamine receptors.