Gutti_2019_Eur.J.Med.Chem_182_111613

Alzheimer's disease (AD) is associated with multifactorial neuropathological conditions, which include cholinergic deficit, amyloid-beta plaques formation, loss of neuronal plasticity and neuronal death. Treating such multifactorial conditions with a single target directed approach is considered to be inadequate. Accordingly, multi-target directed ligand (MTDL) strategy has been evolved as an auspicious approach for the treatment of AD. In light of that, a library of 2-substituted benzo[d]oxazol-5-amine derivatives (29-39; 86-107) was designed using the scaffold hopping guided MTDLs strategy, synthesized and evaluated through various in-vitro and in-vivo biological studies. The optimal compound 92 exhibited potent inhibitory activities against AChE (IC50 = 0.052+/-0.010muM), BuChE (IC50 = 1.085+/-0.035muM), and significant amyloid-beta aggregation (20muM) inhibition. The compound possessed better blood-brain barrier permeability (Pe=10.80+/-0.055x10(-6)cms(-1)) in PAMPA assay and neuro protective properties (40muM) on SH-SY5Y neuroblastoma cell lines. Furthermore, in-vivo behavioural studies were performed on Y-maze test (scopolamine-induced amnesia model) and Morris water maze test (Abeta1-42 induced ICV rat model). The compound 92, at a dose of 10mg/kg oral administration, demonstrated a substantial improvement of the cognitive and special memory impairment. In summary, both in-vitro and in-vivo investigations evidenced that compound 92 was a potential lead for the discovery of safe and effective disease-modifying agents for AD.