Synthesis and biological evaluation of furan-1,3,4-oxadiazole as antitubercular, antibacterial, and antioxidant agents

Abstract

Aim: With the emergence of extensively drug-resistant (XDR) and multidrug-resistant (MDR), tuberculosis (TB) continues to be a major global health concern. This study aims to synthesize and evaluate a new series of furan-1,3,4-oxadiazole hybrids for their multitarget pharmacological potential, including antitubercular, antibacterial, and antioxidant activities.

Materials and methods: A one-pot cyclization approach was used to synthesize furan-1,3,4-oxadiazole derivatives. Structural characterization was performed using IR, NMR, MS, and elemental analyses. Antitubercular activity was evaluated against Mycobacterium tuberculosis H₃₇Rv using the alamar blue assay. Antibacterial activity was tested against Staphylococcus aureus and Escherichia coli, and antioxidant potential was assessed via the DPPH free radical scavenging method. In silico studies evaluated binding affinity and stability with the InhA enzyme to elucidate the potential mechanism of action.

Results and discussion: Among the synthesized compounds, 2l emerged as a promising lead, showing potent antitubercular activity (MIC 3.13 µg/mL), moderate antibacterial effect (MIC 15 µg/mL), and strong antioxidant activity (IC50 < 5 µg/mL). Docking and molecular dynamics simulations confirmed its stable binding to InhA via key interactions. The correlation between biological and computational results underscores the role of electron-withdrawing groups and aromaticity, establishing furan - oxadiazole hybrids as broad-spectrum candidates for further development.

Keywords: Furan-1,3,4-oxadiazole; InhA enzyme; antibacterial agents; antioxidant activity; antitubercular activity; molecular docking; multitarget.