Recent Applications of Click Chemistry for the Synthesis of Radiotracers for Molecular Imaging

Click chemistry has received considerable attention as powerful modular synthesis approach, which has found numerous applications in many areas of modern organic chemistry, drug discovery and material science. Recently, click chemistry, and in particular the copper-mediated 1,3-dipolar [3+2] cycloaddition between azides and alkynes, has also entered the field of radiopharmaceutical sciences. This review addresses the recent developments of click chemistry for the synthesis of various radiotracers for molecular imaging purposes. Click chemistry-based radiotracers that will be covered include peptides and small organic molecules containing the short-lived positron emitter fluorine-18, and the gamma-emitters technetium-99m, indium-111, and iodine-125.