Phthalimide-Derived N-Benzylpyridinium Halides Targeting Cholinesterases: Synthesis and Bioactivity of New Potential Anti-Alzheimer's Disease Agents.

In order to develop potent dual-binding cholinesterase inhibitors as potential drugs for the treatment of Alzheimer's disease, we designed and synthesized phthalimide-based acetylcholinesterase (AChE) inhibitors (7) containing a substituted N-benzylpyridinium residue. The in vitro anti-cholinesterase assay employing the target compounds against AChE and butyrylcholinesterase (BChE) revealed the 2-fluorobenzylpyridinium derivative 7d as the most potent compound against both enzymes, with IC50 values of 0.77 and 8.71 μM. The docking study of compound 7d into the active site of AChE showed the gorge-spanning binding mode, in which the compound spans the narrow hydrophobic gorge from the bottom to the rim.