The present invention relates to compounds represented by the formula: ##STR1## wherein R.sup.1 is (1) an optionally substituted alkyl group which may be bonded through a hetero atom, (2) an optionally substituted acyl group, (3) an alkylsulfonyl group, (4) an alkylsulfinyl group, or (5) an optionally substituted sulfamoyl group; A is --N.dbd. or -CH.dbd.; R.sup.2 is a hydrogen atom or an alkyl group which may optionally be substituted with halogen and which may be bonded through a hetero atom;X.sup.1 is halogen or a lower alkyl group;X.sup.2 is a hydrogen atom or a fluorine atom;R.sup.3 is a hydrogen atom, halogen or a lower alkyl group;and R.sup.4 is a hydrogen atom, an optionally substituted alkyl group or an acyl group, provided that when R.sup.1 is (1) a C.sub.1-4 alkanoyl group, (2) benzoyl, (3) trifluoroacetyl, (4) sulfamoyl which may optionally be substituted with a C.sub.1-4 alkyl group, (5) a C.sub.1-4 alkyl group which may optionally be substituted with hydroxy, halogen or a C.sub.1-3 alkoxy group, (6) amino which is substituted with a C.sub.14 alkyl group, A is --CH.dbd., R.sup.2 is a hydrogen atom, X.sup.1 is a chlorine atom, R.sup.3 is a chlorine atom, and X.sup.2 is a hydrogen atom, then R.sup.4 is an optionally substituted alkyl group or an optionally substituted acyl group; or salts thereof, their production and use thereof. These compounds and salts thereof are useful as anti-protozoal agents.