Transition Metal Complexes of Ethopropazine: Synthesis and Characterization

Ethopropazine (EP) or profenamine is a phenothiazine derivative, N-(2-diethylaminopropyl)phenothiazine (Figure.1), used as an antiparkinsonian drug that has anticholinergic, antihistamine, and antiadrenergic actions. Transition metal complexes of ZnBr2, CdBr2, CdI2, and HgBr2 have been synthesized using EP as the main ligand and purified by recrystallization in MeOH. These products have been characterized based on their elemental analysis, molar conductance, magnetic susceptibility, IR and H-NMR data. The molecular formulations of the new mononuclear complexes have been found to be[Zn(C19H24N2S.HCl)2]Br2,[Cd(C19H24N2S.HCl)2]Br2,[Cd(C19H24N2S.HCl)2]I2 and[Hg(C19H24N2S.HCl) (C19H24N2S.HBr) (OH2)] Br2, where the ligand, EP = C19H24N2S. All the complexes show an ionic ratio of 1:2 in acetonitrile solutions. Molecular structures have been proposed. The four-coordinate complex cations of[Zn(C19H24N2S.HCl)2] Br2,[Cd(C19H24N2S.HCl)2]Br2, and[Cd(C19H24N2S.HCl)2]I2 contain an sp hybridized metal(II) center each with a tetrahedral environment. On the other hand, six-coordinate cationic species of[Hg(C19H24N2S.HCl)(C19H24N2S.HBr)(OH2)]Br2 complex with an spd hybridized metal center exhibits the octahedral geometry.