[18F]azadibenzocyclooctyne ([18F]ADIBO): a biocompatible radioactive labeling synthon for peptides using catalyst free [3+2] cycloaddition.
N-Terminally azido-modified peptides were labeled with the novel prosthetic labeling synthon [(18)F]azadibenzocyclooctyne ([(18)F]ADIBO) using copper-free azide-alkyne [3+2]-dipolar cycloaddition in high radiochemical yields (RCYs). (18)F-Labeled [(18)F]ADIBO was prepared by nucleophilic substitution of the corresponding tosylate in 21% overall RCY (EOB) in a fully automated synthesis unit within 55 min. [(18)F]ADIBO was incubated with azide-containing peptides at room temperature in the absence of toxic metal catalysts and the formation of the triazole conjugate was confirmed. Finally, the azide-alkyne [3+2]-dipolar cycloaddition was shown to proceed with 95% radiochemical yield in ethanol within 30 min, allowing for a development of a kit-like peptide labeling approach with [(18)F]ADIBO.
Department of Chemistry, University of Georgia, Athens, GA, USA.
Selvanathan
S
Arumugam
Joshua
J
Chin
Ralf
R
Schirrmacher
Vladimir V
VV
Popik
Alexey P
AP
Kostikov
D001372:Aza Compounds / Q000737:chemistry*; D002384:Catalysis; D057930:Click Chemistry; D003500:Cyclization; D034242:Cyclooctanes / Q000737:chemistry*; D005462:Fluorine Radioisotopes; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
C571274:(18F)azadibenzocyclooctyne; D001372:Aza Compounds; D034242:Cyclooctanes; D005462:Fluorine Radioisotopes; D010455:Peptides; D019275:Radiopharmaceuticals