Synthesis of novel Schiff base derivatives of tacrine and investigation of their acetylcholinesterase inhibition potency

Abstract

Investigation of acetylcholinesterase (AChE) inhibition potency of some new Schiff base derivatives of tacrine (9-amino-1,2,3,4-tetrahydroacridine) was reported in this paper. Novel Schiff base derivatives of tacrine (3a–g) have been synthesized, and they have been characterized by several methods (FT-IR, 1H-NMR, 13C-NMR, etc.). Then, inhibition effects on AChE by the synthesized compounds have been investigated by the spectrophotometric Ellman method. IC50, Ki, KM and Vmax values and inhibition types have been determined. It was seen that all compounds had the property of a water-soluble reversible AChE inhibitor. Structure 3a was found to be the most potent inhibitor, with the IC50 value of 22.1 ± 1.11 nM (tacrine's IC50 value was calculated as 34.1 nM).

Keywords

• inhibition, acetylcholinesterase, tacrine, schiff base, inhibition type