Abstract
A rapid and efficient methodology was performed for the synthesis of alpha,beta-unsaturated ketones 2a-k containing benzoazonine core through Claisen-Schmidt reaction of the benzoazonine-2,7-dione 1 and various aldehydes in acidic medium. The obtained exocyclic alpha,beta-unsaturated ketones were subjected to an irradiating microwave gave unexpected asymmetric spiro pyran compound 3 via a self-Diels-Alder reaction. The initially formed exocyclic alpha,beta-unsaturated ketones underwent cyclocondesation with phenylhydrazine to afford 2-pyrazoline derivatives 4. The structure of the synthesized scaffolds was characterized using H-1-NMR, APT and 2DNMR spectra. A molecular modeling study using Molecular Operating Environment was performed to investigate their binding modes to the Acetylcholinestrase enzyme active site. Docking results demonstrated that the newly synthesized compounds recognized the active sites of Acetylcholinestrase and form different types of bonding interactions with key active site amino acid residues.