title: Potent 6-desfluoro-8-methylquinolones as new lead compounds in antibacterial chemotherapy.
abstract: In a furtherance of our SAR study on the C-6 position of quinolone antibacterials, a series of 6-desfluoro-8-methylquinolones were synthesized and evaluated for their in vitro antimicrobial activity. As a result of this study, compounds with strong activity against Gram-positive bacteria, including ciprofloxacin-resistant and methicillin-resistant Staphylococcus aureus, were identified. The best Gram-positive antibacterial activity was exhibited by piperidinyl derivative 6c, which was 17 times more potent than ciprofloxacin and displayed extremely high activity against Streptococcus pneumoniae with an MIC value of <0.016 microg/mL. Thus, we have shown that substituent combinations in the quinolone ring, excluding the C-6 fluorine atom, might produce powerful antibacterial agents.
authors.affiliation: Istituto di Chimica e Tecnologia del Farmaco, Università di Perugia, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Cecchetti
authors.forename: A
authors.initials: A
authors.lastname: Fravolini
authors.forename: M
authors.initials: M
authors.lastname: Palumbo
authors.forename: C
authors.initials: C
authors.lastname: Sissi
authors.forename: O
authors.initials: O
authors.lastname: Tabarrini
authors.forename: P
authors.initials: P
authors.lastname: Terni
authors.forename: T
authors.initials: T
authors.lastname: Xin
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D015363:Quinolones / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D015363:Quinolones