Synlett 2024; 35(19): 2207-2211
DOI: 10.1055/a-2147-9303
letter
Isotopic Labeling

Labeling of Highly Reactive Tetrazines using [18F]SuFEx

a   Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
,
Marius Müller
a   Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
b   Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
,
Rocío García-Vázquez
a   Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
b   Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
,
Matthias Manfred Herth
a   Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
b   Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
› Author Affiliations
The work was supported by the Danmarks Frie Forskningsfond (1032-00177B) and the Lundbeck Foundation (grant R303-2018-3567).


Abstract

Pretargeted imaging is an emerging technique to study the in vivo biodistribution of nanomedicines. Currently, the tetrazine ligation is considered the most promising bioorthogonal reaction for pretargeting. Recently, Zheng et al. described an ultrafast late-stage radiolabeling of tetrazines based on sulfur 18F-fluoride exchange click chemistry ([18F]SuFEx). However, bispyridyl and H-tetrazines—the most promising structures for in vivo pretargeted applications—cannot be labeled using the proposed reaction conditions as they lead to decomposition of the tetrazine core. Here, we report improved conditions, exploiting basic preconditioning conditions for the quaternary methyl ammonium (QMA) cartridge and the use of low basic anions that allow 18F-labeling of bispyridyl and H-tetrazines using SuFEx. This strategy resulted in fast and efficient radiolabeling of highly reactive tetrazines with radiochemical conversions of up to 85% and radiochemical purity above 95%. This opens up the possibility to use SuFEx to 18F-label tetrazines, which are suitable for in vivo pretargeted imaging.

Supporting Information



Publication History

Received: 18 July 2023

Accepted after revision: 03 August 2023

Accepted Manuscript online:
03 August 2023

Article published online:
04 October 2023

© 2023. Thieme. All rights reserved

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
  • References

  • 1 Devaraj NK. ACS Cent. Sci. 2018; 4: 952
  • 2 Hang HC, Yu C, Kato DL, Bertozzi CR. Proc. Natl. Acad. Sci. U.S.A. 2003; 100: 14846
  • 4 Rossin R, Verkerk PR, van den Bosch SM, Vulders RC. M, Verel I, Lub J, Robillard MS. Angew. Chem. Int. Ed. 2010; 49: 3238
  • 5 Stéen EJ. L, Jorgensen JT, Denk C, Battisti UM, Norregaard K, Edem PE, Bratteby K, Shalgunov V, Wilkovitsch M, Svatunek D, Poulie CB. M, Hvass L, Simon M, Wanek T, Rossin R, Robillard M, Kristensen JL, Mikula H, Kjaer A, Herth MM. ACS Pharmacol. Transl. Sci. 2021; 4, 824
  • 6 Stéen EJ. L, Edem PE, Nørregaard K, Jørgensen JT, Shalgunov V, Kjaer A, Herth MM. Biomaterials 2018; 179: 209
  • 7 García-Vázquez R, Battisti UM, Herth MM. Pharmaceuticals 2022; 15: 685
  • 8 Selvaraj R, Fox JM. Curr. Opin. Chem. Biol. 2013; 17: 753
  • 9 Rossin R, Läppchen T, Bosch SM. v. d, Laforest R, Robillard MS. J. Nucl. Med. 2013; 54: 1989
  • 10 Jacobson O, Kiesewetter DO, Chen X. Bioconjugate Chem. 2015; 26, 1
  • 11 Stéen EJ. L, Jørgensen JT, Johann K, Nørregaard K, Sohr B, Svatunek D, Birke A, Shalgunov V, Edem PE, Rossin R, Seidl C, Schmid F, Robillard MS, Kristensen JL, Mikula H, Barz M, Kjær A, Herth MM. ACS Nano 2020; 14: 568
  • 12 Denk C, Svatunek D, Filip T, Wanek T, Lumpi D, Fröhlich J, Kuntner C, Mikula H. Angew. Chem. Int. Ed. 2014; 53: 9655
  • 14 Bratteby K, Shalgunov V, Battisti UM, Petersen IN, van den Broek SL, Ohlsson T, Gillings N, Erlandsson M, Herth MM. ACS Pharmacol. Transl. Sci. 2021; 4: 1556
  • 16 Zheng Q, Xu H, Wang H, Du W.-GH, Wang N, Xiong H, Gu Y, Noodleman L, Sharpless KB, Yang G, Wu P. J. Am. Chem. Soc. 2021; 143: 3753
  • 17 Dong J, Krasnova L, Finn MG, Sharpless KB. Angew. Chem. Int. Ed. 2014; 53: 9430
  • 18 Barrow AS, Smedley CJ, Zheng Q, Li S, Dong J, Moses JE. Chem. Soc. Rev. 2019; 48: 4731
  • 20 Herth MM, Ametamey S, Antuganov D, Bauman A, Berndt M, Brooks AF, Bormans G, Choe YS, Gillings N, Häfeli UO, James ML, Kopka K, Kramer V, Krasikova R, Madsen J, Mu L, Neumaier B, Piel M, Rösch F, Ross T, Schibli R, Scott PJ. H, Shalgunov V, Vasdev N, Wadsak W, Zeglis BM. Nucl. Med. Biol. 2021; 93: 19
    • 21a Walter N, Bertram J, Drewes B, Bahutski V, Timmer M, Schütz MB, Krämer F, Neumaier F, Endepols H, Neumaier B, Zlatopolskiy BD. Eur. J. Med. Chem. 2022; 237: 114383
    • 21b Liu Z, Sun Y, Liu T. Front. Chem. 2022; 10
  • 22 Vlastara M, Rossin R, Hoeben FJ. M, Roode KE. d, Boswinkel M, Kleijn LH. J, Nagarajah J, Rijpkema M, Robillard MS. bioRxiv 2023; preprint
  • 23 Battisti UM, García-Vázquez R, Svatunek D, Herrmann B, Löffler A, Mikula H, Herth MM. Bioconjugate Chem. 2022; 33: 608
  • 24 Qu Y, Sauvage F.-X, Clavier G, Miomandre F, Audebert P. Angew. Chem. Int. Ed. 2018; 57: 12057
  • 25 García-Vázquez R, Jørgensen JT, Bratteby KE, Shalgunov V, Hvass L, Herth MM, Kjær A, Battisti UM. Pharmaceuticals 2022; 15: 245
  • 26 General procedure for manual synthesis: To the dry [18F]fluoride was added a mixture of the selected compound (0.0099 mmol) in dry MeCN/DMF (0.5 mL). The reaction was left at room temperature, and quenched with H2O (0.1 mL) after 5 min. Aliquots of the reaction were taken after 1 and 5 min. The aliquots were added to H2O + 0.1% TFA (0.1 mL) and analyzed by radio-HPLC.
  • 27 General procedure for automated synthesis: A solution of either the selected tetrazine (0.5 μmol) in dry MeCN (0.5 mL) or in dry DMF (0.5 mL) was added to the reaction vial containing the dried [18F]Bu4NF (5.0–6.0 GBq), after being cooled with compressed air to room temperature for 8 min. The reaction was left at room temperature for 30 sec, before being immediately quenched with 0.3 mL of H2O + 0.1 % TFA. The crude reaction was then purified via semi-preparative HPLC. Formulation of the product was obtained by diluting the collected fraction with Milli-Q H2O (1:20) and trapping the resulting solution on a C18 solid-phase extraction cartridge. Subsequently, the C18 solid-phase extraction cartridge was washed with Milli-Q H2O (7 mL), and the compound was eluted with EtOH (1 mL), followed by concentration under continuous N2 flow at r.t. The resulting dry [18F]-tetrazine was dissolved in phosphate buffer, resulting in an activity concentration of 100 MBq/mL.