Journal of the American Chemical Society, Vol.142, No.3, 1180-1185, 2020
F-18-Trifluoromethanesulfinate Enables Direct C-H F-18-Trifluoromethylation of Native Aromatic Residues in Peptides
F-18 labeling strategies for unmodified peptides with [F-18]fluoride require F-18-labeled prosthetics for bioconjugation more often with cysteine thiols or lysine amines. Here we explore selective radical chemistry to target aromatic residues applying C-H F-18-trifluoromethylation. We report a one-step route to [F-18]CF3SO2NE4 from [F-18]fluoride and its application to direct [F-18]CF3 incorporation at tryptophan or tyrosine residues using unmodified peptides as complex as recombinant human insulin. The fully automated radiosynthesis of octreotide[Trp(2-(CF2F)-F-18)] enables in vivo positron emission tomography imaging.