The invention relates to antibacterial compounds of formula I wherein U represents CH or N; V represents CH or N, provided that at least one of U and V does not represent N; R represents H, halogen, methyl, methoxy, cyano or ethynyl; either W represents a phenyl group substituted in para position with (C1-C3)alkyl, (C1-C3)alkoxy or (C1-C3)thioalkoxy and optionally in meta position with halogen, or W is a group having one of the formulae W1 and W2 below wherein Q is O or S and X is CH or N; and salts of such compounds.本發明係關於式I之抗菌化合物其中U代表CH或N;V代表CH或N,前提係U及V中之至少一者不代表N;R代表H、鹵素、甲基、甲氧基、氰基或乙炔基;W代表在對位經(C1-C3)烷基、(C1-C3)烷氧基或(C1-C3)硫烷氧基取代且視情況在間位經鹵素取代之苯基,或W係具有以下式W1及W2中之一者之基團其中Q係O或S且X係CH或N;及該等化合物之鹽。