Synthesis and Radioiodinelabeling of β-Amyloid Plaques Imaging Agent 3'-~(131)I-PIB

The synthesis and biodistribution of β-amyloid plaques imaging agent 2-(3'-iodo-4'-methylaminophenyl)-6-hydroxy-benzothialzole(3'-131I-PIB)were reported.The chemical structure of the labeling precursor 2-(3'-tributylstannyl-4'-methylaminophenyl)-6-hydroxy-benzothialzole and all its intermediates were verified by 1H NMR and MS.The radioiodinated compound was prepared using iododestannylation reaction by hydrogen peroxide.Final radiochemical purity is above 95% determined by TLC.The in vivo biodistribution of 3'-131I-PIB in normal mice shows excellent brain uptake and washout,indicating this benzothiazole(BTA) derivative has potential for in vivo imaging amyloid deposits.