Acetylcholinesterase/butylcholinesterase Inhibitory Activities of Substituted Chromenone Derivatives

Abstract

3,6-Disubstituted-2H-2-chromenones 3a-l and 3,4,6-trisubstituted 2H-2-chromenones 3m & 3n were synthesized from 5-bromosalicylaldehyde 1 and 5-bromo-2-hydroxyacetophenone 5. Suzuki coupling of 5-bromosalicylaldehyde with various phenylboronic acids yielded 5-substituted salicylaldehydes 2b-l and these compounds were reacted with various β-ketoesters in presence of piperidine afforded substituted chromenone derivatives 3a-l in very good yields. The compounds 3m & 3n were prepared by Suzuki coupling of 2m. Synthesized compounds 3a-n were screened for in vitro AChE & BuChE activities and found that the compound 3n shown significant activity where as 3g, 3h, 3j, 3k & 3m compounds were shown moderate activity of AChE. The compound 3d shown potent activity, where as 3c & 3m shown moderate activity of BuChE and the results were compared with the standard drug Galanthamine.