title: Synthesis and antibacterial activity of 1-(2-fluorovinyl)-7-substituted-4-quinolone-3-carboxylic acid derivatives, conformationally restricted analogues of fleroxacin.
abstract: The novel 1-(2-fluorovinyl)-4-quinolone-3-carboxylic acid derivatives Z-15a-c, E-15a-c, Z-16a-c, and E-16a-c, conformationally restricted analogues of fleroxacin (5), were synthesized, and their in vitro antibacterial activity was evaluated. A dehydrosulfenylation of a 2-fluoro-2-[(4-methoxyphenyl)sulfinyl]ethyl group was employed as a key step for the construction of a 2-fluorovinyl group at the N-1 position. It appeared evident that the Z-isomers Z-15a-c and Z-16a-c exhibited 2- to 32-fold more potent in vitro antibacterial activity than the corresponding E-isomers E-15a-c and E-16a-c. Furthermore, since Z-15b showed in vitro antibacterial activity and DNA gyrase inhibition comparable to that of 5, it was hypothesized that the conformation of Z-15b would be equivalent to the active conformer of 5. The results revealed that the antibacterial Z-1-(2-fluorovinyl)quinolone derivatives carry the novel N-1 substituent of the fluoroquinolones.
authors.affiliation: Discovery Research Laboratories, Kyorin Pharmaceutical Co. Ltd., 2399-1, Nogi, Nogi-Machi, Shimotsuga-Gun, Tochigi, 329-0114, Japan. yoshikazu.asahina@ mb.kyorin-pharm.co.jp
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Asahina
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Iwase
authors.forename: Fujio
authors.initials: F
authors.lastname: Iinuma
authors.forename: Masaki
authors.initials: M
authors.lastname: Hosaka
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ishizaki
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002264:Carboxylic Acids / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D016576:Fleroxacin / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D002264:Carboxylic Acids; D016576:Fleroxacin