Novel 3-arylfuran-2(5H)-one-fluoroquinolone hybrid: Design, synthesis and evaluation as antibacterial agent

Synthesis and antibacterial activity of novel [1,2,4]triazolo[3,4-h][1,8]naphthyridine-7-carboxylic acid derivatives

“…Elemental analysis was carried out using a PE2400 II instrument. 1-Amino-5-cyclopropyl-10-fluoro-3-thioxo-2,3-dihydro- [1,2,4]triazolo [3,4-h] [1,8]naphthyridine-7-carboxylic acids (4a-4h): To a solution of compound 3 (0.5 g, 1.6 mmol) in absolute ethanol (10 mL) was added the appropriate amine donors (1.6 mmol) followed by a 37% formaldehyde solution (0.5 mL). The mixture was refluxed for 24 h. After the removal of the solvent, the solid residue was dissolved in dilute aqueous hydrochloric acid.…”

“…However, the emergence of bacterial resistance to the quinolones is a growing health problem in the community and hospital settings, and the need for safe and affordable antibacterial agents capable of overcoming the resistance is urgent [2]. Several strategies overcome bacterial resistance being executed and the most effective strategy appears to continually modify the existing classes of antibacterial agents to provide new analogues [3].…”

Modifications of quinolones and fluoroquinolones: hybrid compounds and dual-action molecules

“…The best compound 100 (R 1  = cyclopropyl, R 2  = R 3  = H, R 4  = F, X = CH) was selected for docking studies at the active sites of TyrRS and DNA gyrase. In both cases it was proved to be tightly held in the binding pockets by several hydrogen-bonding interactions and hydrophobic contacts [177] (Fig. 23).…”

Targeting Bacterial Topoisomerases: How to Counter Mechanisms of Resistance

“…The narigenin-ciprofloxacin hybrid showed 8-and 23-fold stronger activity than ciprofloxacin alone when tested against E. coli and S. aureus, respectively [85]. The 3-arylfuran-2(5H)-one pharmacophore-targeting tyrosyl-tRNA synthetase was used to form a hybrid with fluoroquinolone [86]. The strongest compound showed 51-fold greater potency than ciprofloxacin against multidrug-resistant E. coli [86].…”

“…The 3-arylfuran-2(5H)-one pharmacophore-targeting tyrosyl-tRNA synthetase was used to form a hybrid with fluoroquinolone [86]. The strongest compound showed 51-fold greater potency than ciprofloxacin against multidrug-resistant E. coli [86]. These newer quinolone hybrid molecules did not appear to have issues of penetration into Gramnegative bacteria.…”