Visualization of the non-bond interactions between the protein and ligands. Figure A and D showed the interaction between AChE and DL0410. Biphenyl and piperidine rings of DL0410 interacted with TRP286, TYR341 and TRP86 via π-π stacking or π-alkyl interaction. Compound 6-1 showed a strong interaction with AChE (Figure B and E). Except for TRP286, TYR341 and TRP86, compound 6-1 could form hydrogen bonds with TRP72 via carbonyl group. Compound 7-6 also had powerful interactions with AChE, mainly through π-π stacking, π-alkyl and hydrogen bond interaction (Figure C and F). TRP286, TYR341 and TRP86 were the key amino acid residues for AChE interacting with the three compounds.