Synthesis of [131‐I]‐iodinated quercetin

Two iodination procedures via thallation were applied to quercetin leading to the formation of 2′-iodoquercetin and 2′,6,8-triiodoquercetin; their structures being elucidated by FT-IR and NMR spectral analysis. The preparation of mono- and polyiodinated products is discussed here on the basis of the experimental details and spectral data. This is the first report on the radiolabelling of quercetin, which is here selectively performed with 131-iodine. The radiochemical purity was of 99%. © 1997 John Wiley & Sons, Ltd.