Abstract
Recently we have clinically used three new radioligands, [11C]SA4503, [11C]MPDX, and [11C]TMSX, for mapping sigmai, adenosine A1, and adenosine A2A receptors, respectively, in the human brain by positron emission tomography. These radioligands are synthesized by methylation of the respective demethyl precursor with [11C]methyl iodide. Here we demonstrate the improved syntheses of these compounds by use of [11C]methyl triflate, a highly reactive alternative to [11C]methyl iodide.
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Kawamura, K., Ishiwata, K. Improved synthesis of [11C]SA4503, [11C]MPDX and [11C]TMSX by use of [11C]methyl triflate. Ann Nucl Med 18, 165–168 (2004). https://doi.org/10.1007/BF02985109
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DOI: https://doi.org/10.1007/BF02985109