Synthesis and Evaluation of Novel 18F-labeled Oxadiazole-based Positron Emission Tomography Tracers for β-Amyloid

This research details the synthesis, structure-activity evaluation, and analysis of novel oxadiazole-based compounds for visualizing β-amyloid (Aβ) in Alzheimer's disease (AD). The derivatives exhibited binding affinities to Aβ aggregates in vitro. The [18F]-labeled compounds, [18F]4-(5-(4-Fluorophenyl)-1,3,4-oxadiazol-2-yl)-N, N-dimethylaniline (compound [18F] 3) and [18F] 4-(5-(4-Fluorophenyl)-1,3,4-oxadiazol-2-yl)-N-methylaniline (compound [18F]4), effectively labeled Aβ plaques in brain sections from Alzheimer's disease patients and APP/PS1 mice. In dynamic positron emission tomography (PET) studies on healthy mice, these compounds demonstrated favorable brain uptake followed by clearance. Additional structural alterations to compounds [18F] 3 and [18F] 4 may lead to the development of more efficient PET tracers for precise visualization of Aβ plaques.