A Novel Class Substituted Imidazo[2,1-b][1,3,4]thiadiazole Derivatives: Synthesis, Characterization, In Vitro Biological Activity, and Potential Inhibitors Design Studies

In this study, imidazo[2,1-b][1,3,4]thiadiazole derivatives were designed and synthesized. All of the synthesized compounds were characterized by H-1 and C-13 nuclear magnetic resonance (H-1 NMR and C-13 NMR), fourier-transform infrared spectroscopy (FT-IR), elemental analysis, mass spectrometry, and X-ray diffraction. The synthesized compounds were tested for antileishmanial activity against two Leishmania species and antibacterial activity against nine bacterial species in the study. It was observed that 2-(4-Fluorobenzylthio)-6-(4-fluorophenyl)imidazo[2,1-b][1,3,4]thiadiazole (5) had the highest antileishmanial activity (MIC: 625 mu g/mL). Also, 4-(2-(4-fluorobenzylthio)imidazo[2,1-b][1,3,4]thiadiazol-6-yl)benzonitrile (10), 2-(4-fluorobenzylthio)-6-(4-phenylphenyl)imidazo[2,1-b][1,3,4]thiadiazole (11), and 4-(2-(4-methoxybenzyl)imidazo[2,1-b][1,3,4]thiadiazol-6-yl)benzonitrile (25) were found to be effective at different studied concentrations. PyRx software, which uses a Lamarckian genetics algorithm, was utilized to find the affinity values of all compounds in molecular docking simulations. Pharmacokinetic properties and toxicities of the ligands were then researched using PROTOX (a webserver for the prediction of oral toxicities of small molecules) and FAF-Drugs (free adsorption distribution, metabolism, excretion (ADME) tox filtering tool). The study showed that the ligands had acceptable toxicity and ADME properties for the inhibition of the 3JUS receptor.