Abstract: The invention relates to antibiotic compounds of formula (A1) and pharmaceutically acceptable salts, solvates, tautomers and combinations thereof, wherein X and L are optional linkers and one of RA or R1 comprises Ar1, wherein Ar1 is an antibiotic resistance breaker moiety which comprises an optionally substituted C6-10 aryl, C7-13 aralkyl, C5-10 heteroaryl, C6-13 heteroaralkyl, C5-10 heterocyclyl, C6-13 heterocyclalkyl, C3-10 carbocyclyl, C4-13 carbocyclalkyl, —C(?NR?)—NR?R? or —CH2—CH?CH2 group; wherein after administration of the compound to a bacterial infection this moiety reduces or prevents efflux. The invention also discloses pharmaceutical compositions comprising compounds of formula (A1) and the use of such compounds as medicaments, in particular, to treat bacterial infections, such as drug-resistant bacterial infections.

Abstract: The invention relates to antibiotic compounds of formula (A1) and pharmaceutically acceptable salts, solvates, tautomers and combinations thereof, wherein X and L are optional linkers and one of RA or R1 comprises Ar1, wherein Ar1 is an antibiotic resistance breaker moiety which comprises an optionally substituted C6-10 aryl, C7-13 aralkyl, C5-10 heteroaryl, C6-13 heteroaralkyl, C5-10 heterocyclyl, C6-13 heterocyclalkyl, C3-10 carbocyclyl, C4-13 carbocyclalkyl, —C(?NR?)—NR?R? or —CH2—CH?CH2 group; wherein after administration of the compound to a bacterial infection this moiety reduces or prevents efflux. The invention also discloses pharmaceutical compositions comprising compounds of formula (A1) and the use of such compounds as medicaments, in particular, to treat bacterial infractions, such as drug-resistant bacterial infections.