Radiosynthesis and characterization of astemizole derivatives as lead compounds toward PET imaging of τ-pathologyElectronic supplementary information (ESI) available: Experimental procedures. See DOI: 10.1039/c3md00017f

Formation of neurofibrillary tangles, comprising of microtubule-associated tau protein, is a hallmark of a group of neurodegenerative diseases, including Alzheimer's disease. In consequence, in vivo imaging of neurofibrillary tangles is a current focus of positron emission tomography research. Herein, development of an in vitro radioligand binding assay which uses synthetic aggregates as a model of neurofibrillary tangles is reported, together with evaluation of novel derivatives of the tau protein ligand astemizole. Synthesis, radiosynthesis, in vitro binding to synthetic tau fibrils and in vivo PET imaging with a novel candidate radiotracer for tau-pathology are described.