Synthesis of deuterium-labeled fluphenazine

Article abstract of DOI:10.1002/jps.2600730123

The propylpiperazine side chain of fluphenazine has been labeled with two, four, and six deuterium atoms by lithium aluminum deuteride reduction of the appropriate ester or imide. The γ-carbon of the propyl group was labeled with two deuterium atoms by reduction of 10- (2-methoxycarbonylethyl)-2-trifluoromethyl-10H-phenothiazine, while four deuterium atoms were incorporated into the piperazine ring by reduction of 10-[3-(3,5-dioxo-1-piperazinyl)propyl]-2-trifluoro-methyl-10H-phenothiazin e. The latter reduction gave the d₄-labeled N-deshydroxyethyl metabolite of fluphenazine.