Synthesis of ¹¹C-Labelled Symmetrical Ureas via the Rapid Incorporation of [¹¹C]CO₂ into Aliphatic and Aromatic Amines

Abstract

An efficient method to radiolabel symmetrical [¹¹C]ureas using 1,8-diazabicycloundec-7-ene (DBU) and cyclotron-produced [¹¹C]CO₂ has been developed. [¹¹C]urea derivatives were obtained when aliphatic and aromatic amines were used with excellent radiochemical yields (RCYs) of over 70%. The mechanism of the reaction is proposed on the basis of control experiments. This simple and robust methodology provides a powerful tool to prepare ¹¹C-labelled ureas previously inaccessible by existing methods and enable their utilisation for in vivo molecular imaging applications.

Key words

carbon-11 - carbon dioxide - Mitsunobu reaction - symmetrical urea - DBU

• References and Notes

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