Synthesis, Biochemical Characterization, and in-Silico Investigations of Acyl-3-(Ciprofloxacinyl) Thioureas as Inhibitors of Carbonic Anhydrase-II

Abstract

A new series of 1-(acyl/aroyl)-3-(ciprofloxacinyl) thioureas (5a–o) was synthesized by the reaction of ciprofloxacin (4) in dry acetone with acyl isothiocyanate intermediate (3). The synthesized compounds were characterized by FT-IR, 1H-NMR, and 13C-NMR. Furthermore, the synthesized compounds were tested for inhibitory potential against carbonic anhydrase (CA-II) and 15 lipoxygenase (LOX) enzymes. The tested compounds exhibited maximum inhibition of CA-11 with moderate anti-inflammatory potential, at the same concentration, i.e. 100 µM, therefore, can be considered as the selective inhibitors of CA-II. Among the tested derivatives 5g showed remarkable inhibitory activity against CA enzyme with IC50 value of 0.97 ± 0.11 µM and this derivative exhibited approximately 40% inhibition of 15-LOX, indicating that compound has moderate anti-inflammatory properties. The molecular docking studies, density functional theory (DFT) calculations, and molecular dynamic (MD) simulation studies were performed to evaluate their binding affinities, stability, and chemical reactivity within the active pocket of the targeted enzymes. The docking analysis and MD simulation studies revealed that the most active inhibitor 5g showed important interactions within the binding pockets of CA-II and may be responsible for the inhibitory activity of the compound toward the targeted enzymes. Therefore, the screened derivatives provided an outstanding platform for further development of CA inhibitors.