Dual-target ligand discovery for Alzheimer's disease: triphenylphosphoranylidene derivatives as inhibitors of acetylcholinesterase and beta-amyloid aggregation

Alzheimer disease (AD) is one of the major neurodegenerative diseases that could not be prevented or completely cured and may lead to death. Here, we target AChE and beta-amyloid proteins. Synthesising new triphenylphosphporanylidene derivatives based on the surveyed literature and testing their biological activity revealed promising results especially for the acetyl triphenylphosphoranylidene derivative 8c, which showed good inhibitor activity against AChE enzyme with IC50 in the nanomolar range (97.04 nM); on the other hand, it showed poor selectivity for AChE versus butyrylcholinesterase but with some futural structural modification, this selectivity can be improved. 8c showed MMP-2 IC50 of 724.19 nM and A beta(1-42) aggregation IC50 of 302.36 nM. A kinetic study demonstrated that compound 8c uncompetitively inhibited AChE. Moreover, derivative 8c showed low cytotoxicity, good in vivo behavioural studies including Y-maze and passive avoidance tests with activity similar to that of donepezil. Finally, in silico studies for 8c predict its good penetration into BBB and good binding affinity in the AChE binding site.