18F-fluorothiols: a new approach to label peptides chemoselectively as potential tracers for positron emission tomography.
[(18)F]Fluorothiols are a new generation of peptide labeling reagents. This article describes the preparation of suitable methanesulfonyl precursors and their use in no-carrier-added radiosyntheses of (18)F-fluorothiols. The preparations of (3-[(18)F]fluoropropylsulfanyl)triphenylmethane, (2-[2-[2-(2-[(18)F]fluoroethoxy)ethoxy]ethoxy]ethylsulfanyl)triphenylmethane, and 4-[(18)F]fluoromethyl-N-[2-triphenylmethanesulfanyl)ethyl]benzamide starting from the corresponding methanesulfonyl precursors were investigated. Following the removal of the triphenylmethane protecting group, the (18)F-fluorothiols were reacted with the N-terminal chloroacetylated model peptide ClCH(2)C(O)-LysGlyPheGlyLys. The corresponding radiochemical yields of (18)F-labeled isolated model peptide, decay-corrected to (18)F fluoride, were 10%, 32%, and 1%, respectively. These results indicate a considerable potential of (18)F-fluorothiols for the chemoselective labeling of peptides as tracers for positron emission tomography (PET).
Glaser
Matthias
M
Hammersmith Hospital, Hammersmith Imanet Ltd., Du Cane Road, London W12 0NN, U.K. mglaser@csc.mrc.ac.uk
Karlsen
Hege
H
Solbakken
Magne
M
Arukwe
Joseph
J
Brady
Frank
F
Luthra
Sajinder K
SK
Cuthbertson
Alan
A
D005462:Fluorine Radioisotopes / Q000032:analysis* / Q000737:chemistry; D010446:Peptide Fragments / Q000032:analysis* / Q000737:chemistry; D049268:Positron-Emission Tomography / Q000379:methods*; D011849:Radioactive Tracers
D005462:Fluorine Radioisotopes; D010446:Peptide Fragments; D011849:Radioactive Tracers