A compound of the formula I, in any of its stereoisomeric forms or a mixture of stereoisomeric forms in any proportion, or a pharmaceutically acceptable salt thereof, ** Formula ** wherein Ar is selected from the series consisting of phenyl and a 5-membered or 6-membered monocyclic aromatic heterocycle, all of which are unsubstituted or substituted with one or more same or different R1 substituents, wherein the heterocycle comprises 1 or 2 identical or different ring heteroatoms selected from the series consisting of nitrogen , oxygen and sulfur, and is linked by a ring carbon atom； R1 is selected from the series consisting of halogen, alkyl- (C1-C6), cycloalkyl- (C3-C7), cycloalkyl- (C3-C7) -alkyl (C1-C4) -, phenyl, Het1, HO-, -alkyl- (C1-C6) -O-, cycloalkyl- (C3-C7) -O-, -cycloalkyl (C3-C7) -alkyl- (C1-C4) -O-, phenyl-O-, Het1-O - and alkyl- (C1-C6) -S (O) n-, and two R1 groups attached to adjacent ring carbon atoms in Ar, together with the carbon atoms that carry them, can form a 5-membered monounsaturated ring 7-member comprising 0, 1 or 2 same or different ring heteroatoms selected from the series consisting of nitrogen, oxygen and sulfur, and which are unsubstituted or substituted with one or more same or different substituents selected from the series consisting in fluorine and alkyl- (C1-C4)； R2 is selected from the series consisting of R5-N (R6) -C (O) -, R5-N (R6) -CH2-, R7-C (O) -NH-CH2- and R7-S (O) 2-NHCH2-； R3 is selected from the series consisting of hydrogen, halogen, alkyl- (C1-C4) and alkyl- (C1-C4) -O-； R4 is hydrogen or one or more same or different substituents selected from the series consisting of halogen, alkyl- (C1-C4) and alkyl- (C1-C4) -O-； R5 and R6 are independently selected from each other in the series consisting of hydrogen, alkyl- (C1-C6), cycloalkyl- (C3-C7), bicycloalkyl- (C6-C10), phenyl, Het1 and Het2, where Alkulium- (C1-C6) is unsubstituted or substituted with one or more same or different R10 substituents, and cycloalkyl (C3-C
