An efficient synthesis of bis-Schiff's bases of polyhydroquinoline derivatives via multistep reactions, anti-bacterial activities and DFT approach

•Novel bis-Schiff's bases of polyhydroquinoline derivatives are synthesized successfully without use of any catalyst.•Synthesized compounds are characterized by 1H NMR, 13C NMR and LCHREIMS and antibacterial activities are carried out.•Density functional theory simulations are performed to understand the structural and electronic properties of synthesized compounds.