DESIGN SYNTHESIS AND EVALUATION OF IMIDAZOLE [4,5 -B] PYRIDINE BENZO-HYDRAZONE

“The present research focuses on the design, synthesis, and biological evaluation of novel hybrid molecules comprising imidazo[4,5-b] pyridine and benzo-hydrazone scaffolds, aiming to explore their therapeutic potential as antimicrobial, antioxidant, and anticancer agents. A series of nine derivatives (3a–3i) were synthesized through a multistep reaction pathway involving the condensation of imidazo[4,5-b] pyridine-2-carbaldehyde with various substituted benzo-hydrazides. The synthesized compounds were structurally confirmed by FT-IR, NMR, mass spectrometry, and elemental analysis. Biological evaluation revealed that compounds 3f, 3h, and especially 3i exhibited significant antibacterial activity against Staphylococcus aureus, with MIC values as low as 6.25 µg/mL. In DPPH assays, compound 3i demonstrated the highest antioxidant capacity (IC₅₀ = 38.4 µg/mL), comparable to ascorbic acid. Furthermore, cytotoxicity studies against MCF-7 and HeLa cell lines highlighted compound 3i’s potent anticancer activity (IC₅₀ = 29.6 and 27.1 µg/mL, respectively). Molecular docking against DNA gyrase, peroxiredoxin 5, and topoisomerase IIα corroborated the in vitro findings, showing strong binding affinities for compounds 3f and 3i. These results suggest that structural hybridization of imidazo [4,5-b] pyridine and benzo-hydrazone cores offers a promising strategy for the development of multifunctional therapeutic agents.