Design, synthesis, and in vitro evaluation of 4-aminoalkyl-1(2H)-phthalazinones as potential multifunctional anti-Alzheimer’s disease agents

[Display omitted] •4-aminoalkyl-1(2H)-phthalazinone derivatives were designed and synthesized.•Most compounds exhibited significant AChE and MAO-B inhibitory activities.•Some compounds showed good inhibition of self- or Cu2+-induced Aβ aggregation.•Most compounds exhibited significant antioxidant and neuroprotective activities.•Compounds 15b also showed good anti-neuroinflammatory activity and BBB permeability. A series of 4-aminoalkyl-1(2H)-phthalazinone derivatives was designed and synthesized as potential multifunctional agents for Alzheimer's disease (AD) treatment. In vitro biological assay results demonstrated that most synthesized compounds exhibited significant AChE inhibition, moderate to high MAOs inhibitory potencies and good anti-platelet aggregation abilities. Among them, compound 15b exhibited the highest inhibitory potencies towards MAO-B and MAO-A (IC50 = 0.7 µM and 6.4 µM respectively), moderate inhibition towards AChE (IC50 = 8.2 µM), and good activities against self- and Cu2+-induced Aβ1–42 aggregation and platelet aggregation. Moreover, 15b also displayed antioxidant capacity, neuroprotective potency, anti-neuroinflammation and BBB permeability. These excellent results indicated that compound 15b could be worthy of further studies to be considered as a promising multifunctional candidate for the treatment of AD.