SOME NOVEL SCHIFF BASE DERIVATIVES AS PROMISING CHOLINESTERASE INHIBITORS WITH ANTIOXIDANT ACTIVITY AGAINST ALZHEIMER’S DISEASE: SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL EVALUATION

In this manuscript, five novel Schiff base derivatives containing a pyrazolone ring and a sulfonate moiety (6-10) except for 9 were designed, obtained for the first time and characterized by three spectroscopic techniques. The inhibition performances of these moleucles synthesized in two steps against cholinesterases, namely acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were evaluated. By DPPH and ABTS assays, antioxidant activities of these molecules were also examined. In AChE assay, compound 6 (95.87±1.59 % inhibition) inhibited this enzyme better than galanthamine (76.98±0.42 % inhibition). In BChE assay, compound 10 with 87.92±1.08% inhibition value in the series indicated the highest activity compared to galanthamine (76.30±0.28 % inhibition). In ABTS radical scavenging assay, compounds 7, 8 and 9 except for 6 and 10 indicated higher antioxidant activities compared to butylated hydroxytoluene (BHT). It is believed that these results may contribute to the design and synthesis of novel antioxidant agents, AChE and BChE inhibitors.