In vitro and in vivo Investigations of 4-Substituted 2-Phenylquinazoline derivatives as multipotent ligands for the treatment of Alzheimer's disease.

The pathology of Alzheimer's disease (AD) is complex due to its multifactorial nature and single targeting drugs proved inefficient. A series of novel 4-N-substituted-2-phenylquinazoline derivatives was designed and synthesized as potential multi-target directed ligands (MTDLs) through dual inhibition of AChE and MAO-B enzymes along with Aβ42 aggregation inhibition for the treatment of AD. Two compounds in the series, VAV-8 and VAV-19 were found to be the most potent inhibitors of both AChE and MAO-B enzymes and moderate inhibitor of Aβ42, with good thermodynamic stability at the binding pocket of the enzymes. Both the ligands showed moderate ROS inhibition and neuroprotection potential and found to be permeable to the blood-brain barrier. Furthermore, VAV-8 was subjected to toxicity evaluation and in vivo investigation using a zebrafish model. In adult zebrafish, VAV-8 (5 μM, and 10 μM) was found to be effective in reducing cognitive deterioration, neurodegeneration, and oxidative stress induced by scopolamine. Thus, these quinazoline derivatives have the potential to be developed as MTDLs for the treatment of Alzheimer's disease.