Discovery of Huperzine A−Tacrine Hybrids as Potent Inhibitors of Human Cholinesterases Targeting Their Midgorge Recognition Sites

Abstract

We describe herein the development of novel huperzine A-tacrine hybrids characterized by 3-methylbicyclo[3.3.1]non-3-ene scaffolds. These compounds were specifically designed to establish tight interactions, through different binding modes, with the midgorge recognition sites of human acetylcholinesterase (hAChE: Y72, D74) and human butyrylcholinesterase (hBuChE: N68, D70) and their catalytic or peripheral sites. Compounds 5a-c show a markedly improved biological profile relative to tacrine and huperzine A.