Radiochemical synthesis of 2′-[18F]-labelled and 3′-[18F]-labelled nucleosides for positron emission tomography imaging

This review article considers 2'-labelled and 3'-labelled nucleosides, which are of great importance as positron emission tomography (PET) probes in clinical diagnostics and PET research. Although the radiochemical preparation of several [F-18]-labelled nucleosides such as [F-18]fluorothymidine or [F-18](fluoroarabinofuranosyl) cytosine has been accomplished within the last two decades, a number of potentially interesting nucleoside-based biomarkers are not yet available for automated good manufacturing practice production due to the lack of fast and efficient synthetic methods for late-stage [F-18]-introduction. In order to meet recent demands for new PET-based biomarkers in various clinical applications, appropriate precursors that can easily be fluorinated and deprotected need to be developed.