Naphthyridin-2 (1 H)-one compounds useful as antibacterials

12 5 Compounds of Formula (I), wherein substituents R, Rand Rare as defined, and Ar represents substituted phenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiazolyl, furanyl, imidazolyl and thiophenyl substituted by a hydroxyalkyl substituent and an optional other substituent; compositions containing them, their use in therapy, including their use as antibacterials, for example in the treatment of tuberculosis, and methods for the preparation of such compounds, are provided.