Novel nicotinonitrile-coumarin hybrids as potential acetylcholinesterase inhibitors: design, synthesis, in vitro and in silico studies

Abstract

Alzheimer’s disease is a degenerative brain condition that is the leading cause of dementia affecting millions of people around the world. Therapeutic development has focused on the problem of the loss of basal forebrain cholinergic function, as it is the only evidence responsible for brain neurodegeneration in patients with Alzheimer’s disease. Several attempts to improve cholinergic neurotransmission have been investigated by minimizing synaptic degradation of acetylcholine using acetylcholinesterase inhibitors. In the current study, we explore the designing of a new series of nicotinonitrile-coumarin hybrids as potential acetylcholinesterase inhibitors. The new hybrids were prepared utilizing pyridine-2(1H)-thiones as starting precursors. The in vitro acetylcholinesterase (AChE) inhibitory activities were examined for the new nicotinonitrile-coumarin hybrid molecules, when compared with donepezil as a standard drug with IC50 of 14 nM. Coumarin derivative, linked to 6-(4-nitrophenyl)-4-phenylnicotinonitrile, showed more effective inhibitory activity than the reference donepezil with IC50 of 13 nM. The free radical-scavenging capabilities against DPPH of the new hybrid derivatives were screened. Additionally, their in vitro cytotoxic activities have been tested against various eukaryotic cells. Furthermore, docking study showed excellent interaction between nicotinonitrile-coumarin hybrids and AChE.