Compounds for the treatment of protozoal diseases

Compounds of the formula (I)

• 121
• or a salt thereof, where
• Y is C=O, C=S, C=NH,(C=O)2 or SO2;
• (A) and (B) are independently an aromatic hydrocarbon group which optionally contains one or more heteroatoms selected from the group consisting of S, O and N,wherein the heteroatom N is optionally substituted with R′, the heteroatom S is optionally bond to=O or (=O )2;
• R′ is hydrogen, hydroxyalkyl, haloalkyl, aminoalkyl, alkoxy, cyanoalkyl, alkyl or an unsaturated or saturated carbocyclic group selected from the group consisting of cyclopentyl, cyclohexyl, aryl and heteroaryl;
• 122
• where Ra and Rc are independently hydrogen, —O—(CO)—R′ (where R′ is as defined above), hydroxyl, hydroxyalkyl, haloalkyl, aminoalkyl, alkoxy, cyanoalkyl, alkyl or an unsaturated or saturated carbocyclic group selected from the group consisting of cyclopentyl, cyclohexyl, aryl, heteroaryl;
• Rb is an optional substituent which may be independently of Ra and Rc and may be selected from the group as defined above for Ra and Rc;
• Rd is hydrogen or one of the following groups:
• —(CO)—Re where Re is independently hydrogen, alkoxy, alkylthio, halogen, haloalkyl, haloalkyloxy, hydroxyalkyl, hydroxyalkylamino, alkyl, aryl, heteroaryl, amino, aminoalkyl or alkylamino group;
• —(CH2)n—Rf where Rf is independently hydrogen, a hydroxy-alkyl, an alkyl, an allyl, an amino, an alkylamino, a morpholino, 2-tetrahydrofuran, N-pyrrolidino, a 3-pyridyl, a phenyl, a benzyl, a biphenyl or another heterocyclic group and n is 0, 1, 2 or 3;
• —NRa Rb where Ra and Rb are defined above;
• or Ra forms together with Rd a 5- or 6-membered unsaturated or saturated heterocyclic ring which optionally has 0 to 3 times substituents R″;
• the dotted line means a double bond unless there is a substituent Rb in the formula of R1 as defined above.
• R″ is independently hydrogen, alkoxy, alkylthio, aminoalkyl halogen, —CO2R′, —CR′O, haloalkyl, haloalkyloxy, —NO2, —CN, hydroxyalkyl, alkyl, aryl, heteroaryl, amino, alkylamino or aminoalkyl group or a double bounded oxygen, wherein R′ is as defined above;
• R2 is a hydrogen, a halogen, alkoxy, alkylthio, —CO2R′, —CR′O, haloalkyl, haloalkyloxy, —No2, —CN, hydroxy, hydroxyalkyl, alkyl, aryl, amino, alkylamino or aminoalkyl group;
• R3 is a hydrogen, a halogen, haloalkyl, —NO2, —CN,alkyl or aryl group;
• R4 is a hydrogen or a group capable of hydrogen bond formation except for a group as defined for substituent R1;
• R5 is hydrogen or, independently of R4, a group selected from the groups as defined above for R4
• R6 is hydrogen or, independently of R2, a group selected from the groups as defined above for R2;
• and
• with the proviso that the compounds of the formula (I) are not compounds
• in which Y is equal to C=O, both (A) and (B) are a phenyl group, R1′ is the group
• 123
• where R1 is hydrogen or phenyl, R2, R3, R5and R6 are identical and are hydrogen, R4 is phenyl, benzyl, phenoxy, chloro or dimethylamino group in the 3- or 4-position to the NH—Y—NH group of the compound of the formula(I);
• or compounds in which (A) and (B) are phenyl and R4, R′ or R6 are in the ortho-position to the NH—Y—NH group of the compound of the formula(I).