Synthesis, characterization, stereochemistry, antibacterial and antioxidant activity of N-chloroacetyl-2,6-diphenylpiperidines

•Six new amides 13–18 have been synthesized and the conformational analysis was carried out with the help of NMR techniques.•The compound 17 prefers chair conformation with axial phenyl groups.•The remaining compounds 13–16 & 18 prefer to exist in an equilibrium between B1 and B2 conformations.•X-ray crystal structure for the compound 16 supports the boat conformation in the solid state.•All synthesized compounds show promising antibacterial and antioxidant activities. A new series of N-chloroacetyl-2,6-diphenylpiperidines 13–18 have been synthesized from their corresponding piperidines 7–12. The synthesized compound 14 is unambiguously characterized using IR, mass, 1D and 2D (1H–1H, COSY & 1H–13C, HSQC) NMR spectral techniques and the remaining compounds 13–16 & 18 are characterized by IR, mass and 1D NMR spectra. The NMR spectral data indicate that the compound 17 prefers to adopt alternate chair conformation and remaining compounds prefer to adopt boat conformation. The X-ray crystal structure solved for N-chloroacetyl-3-isopropyl-2,6-diphenylpiperidine 16 supports the distorted boat conformation in the solid state. Anti-bacterial evaluation shows that the compounds 15 & 16 demonstrate superior activity against all the tested bacteria. All the synthesized compounds show promising antioxidant activities compared to the standard BHA (butylated hydroxyanisole). [Display omitted]