Synthesis of benzothiazole derivatives and their binding characteristics with β-amyloid

Alzheimer’s disease (AD) is a progressive neurodegenerative disease endangering human health seriously.  Recent reports have revealed that β-amyloid aggregates play a key role in the pathogenesis of AD.  Thus, targeting the Aβ plaques benzothiazole derivatives were synthesized with the scaffold of the most promising imaging agent PIB (¹¹C-6-OH-BTA-1, ¹¹C-2-(4-(methylamino)phenyl)-6-hydroxybenzothiazole) and C=N as linker to study the binding characteristics with the target protein through surface plasmon resonance (SPR) technique.  These derivatives were synthesized through simple yet effective method with high yields and characterized by ¹H NMR and FTIR.  The binding properties (K_D) were determined with Biacore X-100 instrument according to the fitting- plot curve.  Compounds 3a and 3f showed high binding affinity for Aβ₁₋₄₀.  The results suggest that benzothiazole derivatives could be served as a scaffold to develop novel β-amyloid imaging agents for the diagnosis of AD.