Synthesis and In Vitro Antibacterial Activity of Novel Naphthyridinone Derivatives

Naphthyridinone has been reported exhibiting strong antibacterial activity. Now, this study describes a series of novel hydrochloride salts of 5,6,7,8-tetrahydro-1,6-naphthyridin-2-(1H)-one derivatives (10 a-10 l) as potential antibacterial agents and corresponding synthetic routes. The majority of analogues exhibit antibacterial activity against Gram-negative bacteria (E. coli) and Gram-positive bacteria (S. aureus). Several of them (10 a, 10 b, 10 h and 10 i) showed strongly antibacterial activity towards E. coli. Compound 10 l is also the first reported compound to exhibit quorum sensing inhibitory activity against C. violaceum ATCC 12472. The presence of quorum sensing inhibitory compound indicates its potential use in the treatment of bacterial infections.