The invention relates to antibacterial compounds of formula (I) wherein X is N or CH R1 is H or halogen R2 is alkynyloxy or the group M R3 is H or halogen M is one of the groups MA and MB represented below wherein A is a bond, CH2CH2, CH=CH or C≡C R1A is H or halogen R2A is H, alkoxy or halogen R3A is H, alkoxy, hydroxyalkoxy, alkoxyalkoxy, thioalkoxy, trifluoromethoxy, amino, hydroxyalkyl, 2-hydroxyacetamido, 1-aminocyclopropyl, 1 -hydroxymethyl- cycloprop-l-yl, l-((phosphonooxy)methyl)cyclopropyl, l-(((dimethylglycyl)oxy)methyl)cyclopropyl, trans-2 -hydroxymethyl-cycloprop- 1-yl, 1,2-dihydroxy ethyl, 3-hydroxyoxetan-3-yl, 3-(hydroxyalkyl)oxetan-3-yl, 3-aminooxetan- 3-yl, 3-hydroxythietan-3-yl, morpholin-4-ylalkoxy, morpholin-4-yl-alkyl, oxazol-2-yl or [l,2,3]triazol-2-yl and R1B is hydroxyalkyl, dihydroxyalkyl, aminoalkyl, 1 -hydroxymethyl-cycloprop- 1 -yl, 1 -aminomethyl-cycloprop- 1-yl, iraws-2-hydroxymethyl- cycloprop-l-yl, 3-hydroxyoxetan-3-yl, 3-hydroxythietan-3-yl, 1 -(2-hydroxyacetyl)azetidin- 3-yl, l-(2-aminoacetyl)azetidin-3-yl, l-glycylazetidin-3-yl, l-(2-amino- 2-methylpropanoyl)azetidin-3-yl, 3-(2-aminoacetamido)cyclopentyl, trans-(cis-3,4-dihydroxy)-cyclopent-1-yl or 3-hydroxymethylbicyclo [1,1, 1]pentan-1-yl and salts thereof.La invención se refiere a compuestos antibacterianos de la fórmula I (ver Fórmula) en donde X es N o CH R1 es H o halógeno R2 es alquiniloxi o el grupo M R3 es H o halógeno M es uno de los grupos MA y MB representados a continuación (ver Fórmula) en donde A es un enlace, CH2CH2, CH=CH o C?C R1A es H o halógeno R2A es H, alcoxi o halógeno R3A es H, alcoxi, hidroxialcoxi, alcoxialcoxi, tioalcoxi, trifluorometoxi, amino, hidroxialquilo, 2-hidroxiacetamido, 1-aminociclopropilo, 1-hidroximetil-cicloprop- 1-ilo, 1-((fosfonooxi)metil)ciclopropilo, 1-(((dimetilglicil)oxi)m etil)ciclopropilo, trans-2-hidroximetil-cicloprop-1-ilo, 1,2-dihidroxietilo, 3-hidroxioxetan-3-ilo, 3-(hidroxialquil)oxetan -3-ilo, 3-aminooxetan-3-ilo, 3-hidroxiti
