Design, synthesis, biological evaluation of a new tricyclicthiazolopy-rimidinone derivatives as acetylcholinesterase inhibitors

The novel serious of tricyclicthiazolo[5,4-d]pyrimidinone were designed and synthesized as acetylcholinesterase (AChE) inhibitor agents. The main factors affecting the reactions of syntheses and the structure–activity relationships (SARs) were investigated as well. All compounds were confirmed by ¹H NMR, ¹³C NMR, and HRMS. The in vitro enzyme assays proved that most of the compounds effectively inhibited AChE in the micromolar range with little cytotoxicity. Especially the compound G15 exhibited the best inhibitory activity against AChE with IC₅₀ values of 4.41 ± 0.46 μM. Furthermore, kinetic analysis and molecular modeling studies pointed out the competitive inhibition manner of G15 on AChE. Thus, the derivative G15 can be considered a promising leading compound on AChE.