New 4-Thiazolidinone-Bearing Fluoroquinolone Derivatives: Synthesis, Antimicrobial Effectiveness, Structural Characterization, and In Silico Docking Analysis

Abstract

A series of ciprofloxacin-based thiazolidinone derivatives were developed and prepared by reacting active methylene compound with corresponding aldehydes. The novel compounds were analyzed using several spectroscopic techniques (FT-IR, ¹H, ¹³C NMR and MS), and their antimicrobial properties were tested. Their minimum inhibitory concentration values were between 1.6 and 72.1 µg/mL, similar to MXF (1.9–3.5 µg/mL). From screening, the antibacterial results showed that p-chlorobenzylidene, p-dimethylaminobenzylidene, and m-methoxybenzylidene derivatives showed outstanding antibacterial activity against E. coli with zone of inhibition values of 27±0.1, 21±0.1, and 22±0.3 mm, respectively. The molecular docking predictions showed that the most active compounds have good binding affinities with E. coli DNA gyrase (7C7N). ADMET predictions were performed; the most thiazolidines possess the highest drug likeness score (1.23–1.61) as a promising pharmacokinetic safety profile.