The present invention relates to a compound of formula (I):wherein A is N or CH； B is N O, or S； R1 is H, a (C1-C4)alkyl group, a methyl(C1-C6)cycloalkyl group or a (C1-C6)cycloalkyl group； R2 is an aryl, an arylmethyl group or a methylheteroaryl group such as methylpyridine and methylthiophene； R3 is absent when B is O or S, or is H or a (C1-C4)alkyl group when B is N； R4 is a (C1-C5)alkyl group or a (C1-C4)cycloalkyl group, each group bearing a carboxylic acid group, and said (C1-C5)alkyl group or (C1-C4)cycloalkyl being optionally substituted by a hydroxyl group, a halogen group or a methoxy group, and when B is N, R3 and R4 can together form a 5- or 6-membered heterocycle substituted by a carboxylic acid group, and optionally substituted by a halogen atom, a hydroxyl group, a methoxy group or a hydroxymethyl group, or anyone of its pharmaceutically acceptable salt, for use in the treatment of a disease characterized by a reduction in macrophage-mediated bacterial killing.The present invention further relates to a few compounds which are new to the corresponding pharmaceutical composition for the same use.
