Based on a literature review of the pharmacological effectiveness of phenothiazines, it was theorized that neuroleptic activity could be greatly enhanced by replacing the trifluoromethyl substituent of fluphenazine (la) with a substituent possessing greater electron-withdrawing properties either by inductive or resonance interaction. 1 A 2-substituent with greater electron-attracting properties would decrease the availability of electrons on the sulfur ...
