β-Carboline as a Privileged Scaffold for Multitarget Strategies in Alzheimer’s Disease Therapy

The natural β-carboline alkaloids display similarities with neurotransmitters that can be favorably exploited to design bioactive and bioavailable drugs for Alzheimer’s disease (AD) therapy. Several AD targets are currently intensively being investigated, divided in different hypotheses: mainly the cholinergic, amyloid β (Aβ), Tau hypotheses. To date, only symptomatic treatments available involving acetylcholinesterase NMDA inhibitors. On basis of plethoric single-target structure–activity relationship studies, scaffold was identified as a powerful tool fostering activity molecular interactions wide range AD-related targets. This knowledge undoubtedly used multitarget-directed ligands, highly relevant strategy preferred context multifactorial pathology intricate etiology such AD. In this review, we first individually discuss β-carbolines, then focus on multitarget strategies dedicated deliberate new efficient scaffolds.