Alzheimer's disease (AD) is multifactorial, which makes the design of multi-target-directed ligands an attractive strategy for the development of anti-AD drugs. In order to enhance the anti-AD effects and reduce the toxicity, two usnic acid (UA) derivatives (1-2) were designed, synthesized and fully characterized by introducing dimethylamine Schiff base moiety into the toxic "triketone" portion. Ellman's method and molecular docking were used to test the cholinesterase inhibitory activities. Antioxidant activities were studied with Fenton reaction, cyclic voltammetry and C. elegans. The results showed that compared with UA, 1-2 had stronger anti-cholinesterase activities and similar antioxidant activities. Notably, solvent evaporation of 2 and ZnCl