The aim of this thesis was to search for new, multifunctional ligands targeting two enzymatic systems: cholinesterases and β˗secretase, along with two processes: aggregation of neurotoxic β-amyloid and of tau proteins, both related to the underlying mechanisms of Alzheimer’s disease.We have designed compounds with a three-part molecular structure, consisting of pharmacophores which mediate activity towards selected biological targets. The first pharmacophore we have chosen was benzylamine, a fragment which appears in many inhibitors of cholinesterase, β˗secretase and β-amyloid aggregation. In the central part, which interacts with the catalytic dyad of β-secretase, we placed two alternative scaffolds: various heterocyclic amines and hydroxyalkylamine. As the terminal fragment we incorporated a phthalimide or a saccharine moiety, as well as various amines selected in virtual screening. All compounds were synthesized and subsequently evaluated for biological activity in an in vitro assay. Results confirmed their variable activity towards the presented biological targets. Based on these results, we performed structure-activity relationship analyses.Our work resulted in identification of compound 98 as a lead structure, which selectively inhibits butyrylcholinesterase activity (eqBuChE IC50 = 2.92 µM, hBuChE IC50 = 5.74 µM) in preference to acetylcholinesterase. Its activity profile also involves inhibition of disease-modifying targets and mechanisms: β-secretase (IC50 = 41.60 µM), aggregation of β-amyloid (IC50 = 3.09 µM) and aggregation of the tau protein (53.8% at 10 µM).