Abstract: The present invention concerns the compounds of formula (I) their N-oxides, salts, stereoisomeric forms, racemic mixtures, prodrugs, esters and metabolites, wherein n is 1, 2 or 3; R1 is H, CN, halo, aminoC(?O), C(?O)OH, C1-4alkyloxyC(?O), C1-4alkylC(?O), mono- or di(C1-4alkyl)aminoC(?O), arylaminoC(?O), N-(aryl)-N—(C1-4alkyl)aminoC(?O), methanimidamidyl, N-hydroxy-methanimidamidyl, mono- or di(C1-4alkyl)methanimidamidyl, Het, or Het2; R2 is H, C1-10alkyl, C2-10alkenyl, C3-7cycloalkyl, wherein said C1-10alkyl, C2-10alkenyl and C3-7cycloalkyl may be optionally substituted; R3 is nitro, cyano, amino, halo, hydroxy, C1-4alkyloxy, hydroxyC(?O), aminoC(?O), C1-4alkyloxyC(?O), mono- or di(C1-4alkyl)aminoC(?O), C1-4alkylC(?O), methanimidamidyl, mono- or di(C1-4alkyl)methanimidamidyl, N-hydroxy-methanimidamidyl or Het1; for use as a medicine. The invention further relates to a novel subgroup of the compounds of formula (I), and to compositions comprising compounds of formula (I).