Labeled rhenium complexes: radiofluorination, α-MSH cyclization, and deuterium substitutions

Abstract

While radiopharmaceuticals incorporating rhenium-188 or rhenium-186 radioisotopes have been well documented in the literature, the labeling of rhenium complexes with alternative isotopes has received comparatively less attention. Such rhenium complexes have demonstrated significant utility in imaging melanoma tumors via complexation with α-melanocyte-stimulating hormone (α-MSH) analogues conjugated with radiometals and radiohalogens, improving fluorine-18 incorporation into ligands which were otherwise unable to be synthesized and elucidating improved understandings of rhenium mechanisms and coordination sites through deuterium incorporation. This review highlights each of these rhenium-labeling cases and discusses the benefits derived therein, thus providing a useful resource for researchers intending to label unique rhenium complexes. © 2020 American Chemical Society