Copper-Mediated Late-Stage Iodination and 123I-Labelling of Triazole-benzimidazole Bioactives

Richard Fjellaksel; Rune Sundset; Patrick J. Riss; Jørn H. Hansen

doi:10.1055/s-0036-1591985

Synlett, Table of Contents

Synlett 2018; 29(11): 1491-1495
DOI: 10.1055/s-0036-1591985

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Copper-Mediated Late-Stage Iodination and ¹²³I-Labelling of Triazole-benzimidazole Bioactives

Richard Fjellaksel

^aMedical Imaging Group, Department of Clinical Medicine, UiT The Arctic University of Norway, 9037 Tromsø, Norway

^bDrug Transport and Delivery Group, Department of Pharmacy, UiT The Arctic University of Norway, 9037 Tromsø, Norway

^cOrganic Chemistry Group, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway Email: jorn.h.hansen@uit.no

,

Rune Sundset

^aMedical Imaging Group, Department of Clinical Medicine, UiT The Arctic University of Norway, 9037 Tromsø, Norway

^dPET imaging center, Division of Diagnostics, UNN – University Hospital of North-Norway, 9038 Tromsø, Norway

,

Patrick J. Riss

^eDepartment of Neuropsychiatry and Psychosomatic Medicine, Oslo University Hospital, Oslo, Norway

^fRealomics SFI, Department of Chemistry, University of Oslo, PO BOX 1033, Oslo 0371, Norway

^gNorsk Medisinsk Syklotronsenter AS, Postboks 4950 Nydalen, Oslo 0424, Norway

,

Jørn H. Hansen*

^cOrganic Chemistry Group, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway Email: jorn.h.hansen@uit.no

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Abstract

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Abstract

The copper-mediated azide-alkyne cycloaddition has been studied to achieve late-stage introduction of iodine onto novel triazole-benzimidazole Gonadotropin Releasing Hormone (GnRH)-receptor antagonists. Moreover, the reaction conditions can affect a direct regioselective C–H iodination of the benzimidazole, leading to a range of novel iodo-analogues. The methodologies are powerful strategies for late-stage ¹²³I-labelling of complex bioactives. Our investigations have generated two highly promising ¹²³I-labelled radiotracer candidates that retain high affinities for the GnRH-receptor.

Key words

CuAAC - GnRH antagonist - radiotracer - triazoles - ¹²³I-labeling

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References

References and Notes
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