Fluoronaphthyridines as Antibacterial Agents. 4. Synthesis and Structure-Activity Relationships of 5-Substituted-6-fluoro-7-(cycloalkylamino)-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic Acids

Article abstract of DOI:10.1021/jm00081a013

A series of 5-substituted-6-fluoro-7-(cycloalkylamino)-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acids have been prepared and tested for their in vitro and in vivo antibacterial activities.The 5-methyl group gave better in vitro activity with the 1-cyclopropyl appendage, but poorer activity with the 1-tert-butyl moiety.With the 1-(2,4-difluorophenyl) substitution, the influence of the 7-cycloalkylamino group was determinant: a (3S)-3-aminopyrrolidine was shown to enhance greatly the in vitro and in vivo activity of the 5-methyl derivative.Compound 33 (BMY 43748) was selec ted as a promising candidate for an improved therapeutic agent.