18F-Trifluoromethanesulfinate enables Direct C-H 18F-Trifluoromethylation of Native Aromatic Residues in Peptides.
Kee CW., Tack O., Guibbal F., Wilson T., Isenegger P., Imiołek M., Verhoog S., Tilby M., Boscutti G., Ashworth S., Chupin J., Kashani R., Poh A., Sosabowski JK., Macholl S., Plisson C., Cornelissen B., Willis MC., Passchier J., Davis BG., Gouverneur V.
18F-Labeling strategies for unmodified peptides with [18F]fluoride require 18F-prosthetics for bioconjugation more often with cysteine thiols or lysine amines. Here, we explore selective radical chemistry to target aromatic residues applying C-H 18F-trifluoromethylation. We report a one-step route to [18F]CF3SO2NH4 from [18F]fluoride, and its application to direct [18F]CF3-incorporation at tryptophan or tyrosine residues using unmodified peptides as complex as recombinant human insulin. The fully automated radiosynthesis of octreotide[Trp(2-CF218F)] enables in vivo PET imaging.