(2-[Fluoro]Ethoxy)Benzoxazole: A Novel PET Agent for In Vivo Detection of Dense Amyloid Plaques in Alzheimer’s Disease Patients

Extensive deposition of dense amyloid fibrils is a characteristic neuropathologic hallmark in Alzheimer’s disease (AD). Noninva-sive detection of these molecules is potentially useful for early and precise detection of patients with AD. This study reports a novel compound, 2-(2-[2-dimethylaminothiazol-5-yl]ethenyl)-6-(2-[fluoro]ethoxy)benzoxazole (BF-227), for in vivo detection of dense amyloid deposits using PET. Methods: The binding affin-ity of BF-227 to amyloid-b (Ab) fibrils was calculated. The binding property of BF-227 to amyloid plaques was evaluated by neuro-pathologic staining of AD brain sections. Brain uptake and in vivo binding of BF-227 to Ab deposits were also evaluated using mice. For clinical evaluation of 11C-BF-227 as a PET probe, 11 normal (healthy) subjects and 10 patients with AD participated in this study. Dynamic PET images were obtained for 60min after administration of 11C-BF-227. The regional standardized uptak