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Updated: Dec 26, 2025
A11-positive β-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis
Published on: May 22, 2018
Donepezil-based hybrids as multifunctional anti-Alzheimer's disease chelating agents: Effect of positional
Marina Costa1, Romane Josselin1, Diana F Silva2
1Centro de Química Estrutural and Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av, Rovisco Pais 1, 1049-001 Lisboa, Portugal.
Abstract:
The intricate and multifactorial nature of Alzheimer's disease (AD) requires the development of compounds able to hit different pathophysiological targets, such as cholinergic dysfunction, deposits of amyloid beta (Aβ) peptide and metal dyshomeostasis. In order to continue the search for new anti-AD drugs, a design strategy was once more followed based on repositioning donepezil (DNP) drug, by ortho-attaching a benzylpiperidine mimetic of DNP moiety to a hydroxyphenyl-benzimidazole (BIM) chelating unit (compound 1). Herein, compound 1 and a positional isomer 2 are compared in terms of their potential multiple properties: both present good acetylcholinesterase (AChE) inhibition (low μmolar range) and are moderate/good inhibitors of Aβ self- and Cu-mediated aggregation, the inhibition process being mainly due to ligand intercalation between the β-sheets of the fibrils; compound 1 has a higher chelating capacity towards Cu2+ and Zn2+ (pCu = 14.3, pZn = 6.4, pH 7.4, CL/CM = 10, CM = 10-6 M) than 2 (pCu = 10.7, pZn = 6.3), attributed to its ability to establish a tridentate (N,O,O) coordination to the metal ion. Both compounds are eligible as drug candidates for oral administration but compound 1 shows improved neuroprotective role by completely preventing Aβ-induced cell toxicity.
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