Synthesis and Characterization of Substituted 5-(2-Chloroquinolin-3-yl)-1,3,4-oxadiazole-2-amines: Computational, In Silico ADME, Molecular Docking, and Biological Activities

A series of 5-(2-chloroquinolin-3-yl)-1,3,4-oxadiazole-2-amine (IIIa–IIIj) with different biological activities were designed and synthesized through the cyclization of semicarbazone. All the newly synthesized compounds were characterized by elemental analysis, 1H NMR, 13C NMR, FT-IR, and mass spectrometry. All the newly synthesized final compounds (IIIa–IIIj) were screened for in vitro antimicrobial activity by diffusion into agar wells using Gentamicin as the antibacterial agent and Fluconazole as the antifungal control. In addition, selected compounds were screened for antitubercular activity using Microplate Alamar Blue Assay (MABA). All the compounds were evaluated computationally for drug similarity using various pharmacokinetic studies and ADME-T characterization, then tested in vitro against Gram+ bacteria (Staphylococcus aureus and Bacillus subtilis), Gram– bacteria (S. typhi and P. aeruginosa), fungi (Aspergillus niger and Fusarium), as well as the Mycobacterium tuberculosis H37Rv strain, provided important information about activity against these strains. In the current study, we have discussed the method for the synthesis of 1,3,4-oxadiazole derivatives and summarized the role of compounds (IIIa), (IIIb), (IIId), (IIIg), (IIIh), and (IIIi) as potential antibacterial and antitubercular agents. We put forward further in vivo evaluation and biological activity evaluation for their use against these pathogens.