The invention relates to antibacterial compounds of formula I, wherein R1 is H or halogen; R2 is the group M; R3 is H or halogen; M is MA or MB wherein A is a bond or C≡C; R1A is H or halogen; R2A is H, alkoxy or halogen; R3A is H, alkoxy, hydroxyalkoxy, hydroxyalkyl, 1,2-dihydroxyethyl, dialkylamino, 1-hydroxymethyl-cycloprop-1-yl, 1-((dimethylglycyl)oxy)methyl-cycloprop-1-yl, 3-hydroxyoxetan-3-yl, morpholin-4-ylalkyl or morpholin-4-ylalkoxy; and R1B is a group as defined in claim 1; and salts thereof.