New N-methylpiperazinyl derivatives of bicyclic antiprotozoal compounds

► N-Methylpiperazinyl group as bridgehead substituent of bicyclic antiprotozoals. ► N-Methylpiperazinyl as terminal group of the side chain of bicyclic octanes and nonanes. ► Aminoethyl-2-aza-nonane shows high antiplasmodial activity and excellent selectivity. ► Bicyclo-octyl ω-aminoesters with improved antitrypanosomal and antiplasmodial action.