Synthesis and optical properties of 4-(2-{[6-(1,1-dicyanoprop-1-en-2-yl)naphthalen-2-yl] (methyl)amino} ethoxy)-4-oxobutanoic acid fluorescent probe for beta-amyloid

摘要

A novel 4-(2-{[6-(1,1-dicyanoprop-1-en-2-yl)naphthalen-2-yl](methyl)amino} ethoxy)-4-oxobutanoic acid (5) fluorescent probe for beta-amyloids was synthesized by catalytic acylation using 4-dimethylaminopyridine between succinic anhydride and (1-{6-[(2-hydroxyethyl)(methyl) amino]-2-naphthyl}ethylidene)malononitrile (4). The structures of all compounds were identified by proton nuclear magnetic resonance spectroscopy, infrared spectroscopy, mass spectrometry, and ultraviolet-visible (UV-Vis) spectroscopy. The UV-Vis and fluorescence spectra of 1-{6-[(2-hydroxyethyl)(methyl) amino]-2-naphthyl}ethan-1-one (3), 4, and 5 in solvents with different polarities were investigated, and the effects of solvent polarity on the optical properties of the three compounds were studied. The objective product 5 showed high binding affinities toward A beta(1-40) aggregates in vitro (K (d) = 29.4 nmol/L) by fluorophotometry. This study provides a powerful fluorescent probe for the molecular diagnosis of Alzheimer's disease.