Ferulic acid and benzothiazole dimer derivatives with high binding affinity to β-amyloid fibrils

New ferulic acid and benzothiazole dimer derivatives were synthesized and evaluated by in vitro competition assay using [125I]TZDM for their specific binding affinities to Aβ fibrils. In particular, 4a showed the most excellent binding affinity (Ki = 0.53 nM), compared to PIB (Ki = 0.77 nM), for benzothiazole binding sites of Aβ1–42 fibrils. This result suggests a possibility of a potential AD diagnostic probe for detection of Aβ fibrils.