ML-based prediction to experimental validation: Development of dihydroquinazoline based multi-potent ligands as...

Alzheimer's disease (AD) is a multifactorial neurological disorder accounting for the cognitive decline in the patients. The disease is linked to numerous pathological factors including hyperactivation of acetylcholinesterase (AChE) and monoamine oxidase B (MAO-B), accumulation of amyloid-beta (Aβ) plaques and neurofibrillary tangles in the brain etc. The single-target medications already available in the market are found to be ineffective and the research focus is shifting towards the development of multitargeting agents. In order to find a multi-potent inhibitor against AChE, MAO-B and Aβ_1-42, in the present study we employed a machine learning-based tool, PyRMD, to screen an in-house generated library of dihydroquinazoline derivatives. This screening process identified six promising compounds, KV-271, KV-832, KV-968, KV-1131, KV-1159, KV-1234 with dual inhibition potential against AChE and MAO-B enzymes. In the docking studies, these compounds showed good interactions at the active cavity of the AChE and MAO-B comparable to the standard inhibitors donepezil (AChE) and pargyline (MAO-B). To validate these predictions, the six identified compounds were synthesized and subjected to in vitro enzymatic assays. All the six compounds displayed significant inhibitory activity, with IC₅₀ values below 5 μM for both AChE and MAO-B. Amongst these compounds, KV-1131 and KV-1234 were found to be the most potent inhibitors with IC₅₀ values of 0.93 μM and 0.85 μM against AChE and IC₅₀ values of 1.17 μM and 0.79 μM against MAO-B, respectively. In addition, KV-1131 and KV-1234 exhibited inhibitory activity against Aβ_1-42 self-aggregation inhibition of 34.79 % and 45.70 %, respectively, after 48 h of incubation. Both KV-1131 and KV-1234 were found to be non-toxic up to 10 μM concentration and showed neuroprotective potential against 6-hydroxydopamine induced neurotoxicity in the SHSY-5Y cells. Thus, KV-1131 and KV-1234 were identified as potent leads that can be developed as drug candidates for the treatment of Alzheimer's disease.