Synthesis and Spectral Characterization of Thiosemicarbazone and Hydrazone Derivatives of 6‐(4‐Chlorophenyl)‐3‐Ethyl‐2‐(4‐Methoxyphenyl) Piperidin‐4‐One: Computational, Antibacterial, and Molecular Docking Studies

In the present study, 6-(4-chlorophenyl)-3-ethyl-2-(4-methoxyphenyl) piperidin-4-one 15 were synthesized via a Mannich reaction, thiosemicarbazone 16 and hydrazone derivatives 17 and 18 of 15 were synthesized by the condensation reaction. The chemical structures were confirmed by IR, mass, ¹H, and ¹³C NMR spectral data. The DFT calculations were performed using the Gaussian-16. Geometry optimization was carried out and selected geometrical parameters such as HOMO-LUMO energies, molecular electrostatic potential (MESP) surfaces and atomic Mulliken charges were derived. The compounds were screened for antibacterial activity, which demonstrated inhibited growth of Vibrio cholerae, Staphylococcus aureus and Bacillus spp., with MIC values ranging from 1.562-6.250 µg/mL, respectively. All the synthesized compounds exhibited strong docking interactions with the 4F3C protein receptor with binding energies ranging from -11.68 to -10.62 kcal/mol suggesting their potential as effective inhibitors.