Synthesis and leishmanicidal activity of 1,3-dithiolanes (2a,b), 1,3-dithiane (2c), tetraazaacenaphthene (4a-h) and tetraazaphenalene (4i,j), imidazolidin-2-ylidene (5a,6a,b) and hexahydropyrimidin-2-ylidene (5b) derivatives are described. Some of the screened compounds have demonstrated significant leishmanicidal activity in in vitro and in vivo evaluations.