Deoxygenation of the diol groups in rings A and D of neomycin in combination with the introduction of an N1-(l)-HABA group in the 2-deoxystreptamine subunit (ring B) leads to a novel and potent antibiotic (1) with activity against strains of S. aureus carrying known aminoglycoside resistance determinants, as well as against an extended panel of Methicillin-resistant S. aureus isolates (n = 50). Antibiotic 1 displayed >64 fold improvement in MIC50 and MIC90 against this MRSA collection when compared to the clinically relevant aminoglycosides amikacin and gentamicin. The synthesis was achieved in six steps and 15% overall yield.
Keywords: Aminoglycoside; MRSA; antibiotics; deoxygenation; enzymatic modification; neomycin analogues; resistance.