A series of N-substituted morpholines 2-20 was synthesised by reacting various acid chlorides and alkyl halides with morpholine (1). All of the synthesised compounds 2-20 were screened for their leishmanicidal effects using amphotericin B (IC(50) = 0.24 microg L(-1)) and pentamidine (IC(50) = 2.56 microg mL(-1)) as standards and a structure-activity relationship (SAR) study was established. The compounds 2 (IC(50) = 48 microg mL(-1)), 3 (IC(50) = 30.0 microg mL(-1)), 10 (IC(50) = 41.0 microg mL(-1)), 15 (IC(50) = 33.0 microg mL(-1)), 16 (IC(50) = 35.0 microg mL(-1)) and 20 (IC(50) = 47.0 microg mL(-1)) showed weak leishmanicidal activities.