Unexpected dihydropyridinium derivatives using a multicomponent reaction containing unprotected amino acids

Abstract

In this study, a multicomponent reaction (MCR) of amino acids, aldehydes, β-dicarbonyl compounds, and malononitrile is presented to obtain a novel class of dihydropyridinium scaffolds which are incorporating amino acid moieties. Some derivatives were obtained in tetrahydropyrido[2,3-d]pyrimidin form. The reaction proceeded through formation of a stable enolate as triethylammoniumenolate salt, which is isolable from the reaction mixture. The DFT calculations also confirm the stability of the formed dihydropyridinium structure. The docking studies of the synthesized compounds on the acetylcholinesterase target (PDB ID = 5FUM) show high potential inhibitory activities of these compounds in Alzheimer's disease.