Synthesis, Biological Evaluation, and Molecular Modeling Studies of Novel Chalcone–Pyridinium–Hydrazone Hybrids

Molecular hybridization, which integrates two or more pharmacophores within a single molecular framework, has emerged as a useful strategy for developing compounds with improved biological and drug-like properties. In this study, a novel series of 10 chalcone–pyridinium–hydrazone hybrids (2a–j), incorporating a cinnamamide-derived unit, a quaternized pyridinium moiety, and a hydrazone linkage, was designed and synthesized via a two-step synthetic route. The structures of the synthesized compounds were confirmed by ¹H-NMR and ¹³C-NMR spectroscopy. Cytotoxicity was evaluated in HUVEC and BEAS cells using MTT and SRB assays, while antioxidant-related effects were assessed using DPPH, glutathione (GSH), and total antioxidant status (TAS) assays. The compounds showed limited cytotoxicity in the tested normal cell models, while significant changes were observed in selected antioxidant-related parameters, including total protein content and TAS. To further assess their pharmacological potential, in silico evaluation using SwissADME, pkCSM, and ProTox-3.0 identified the 2-pyridyl and 2-furyl derivatives as the most favorable candidates in terms of predicted drug-like properties, with a bioavailability score of 0.55. However, predicted interactions with P-glycoprotein and potential hERG II inhibition were identified as liabilities across the series. SwissTargetPrediction suggested cholinesterases as potential molecular targets, while molecular docking indicated plausible interactions with acetylcholinesterase and butyrylcholinesterase. Overall, these findings identify chalcone–pyridinium–hydrazone hybrids as promising candidates for further investigation, particularly with respect to their antioxidant potential, pharmacological properties, and possible cholinesterase-related activity. Additional experimental studies are required to confirm their molecular targets and optimize their efficacy and safety profiles.