The effect of the [18F]-PEG group on tracer qualification of [4-(phenylamino)-quinazoline-6-YL]-amide moiety—An EGFR putative irreversible inhibitor

Previous reports have designated the labeled derivatives of [4-(phenylamino)-quinazoline-6-yl]-amide group as the most promising EGFR-PET imaging agent candidates. To further improve tracer qualifications and increase stability and solubility, additional derivatives of this group substituted at the 7-position with various lengths of fluoro-polyethyleneglycol (F-PEG) chains were synthesized. These novel derivatives inhibited EGFR autophosphorylation with IC50 values of 5–40 nM. The compounds were successfully labeled with fluorine-18 at the PEG chain via a three-step radiosynthesis route. The labeled final products were obtained with a 13–32% decay corrected radiochemical yield, 99% radiochemical purity, and high specific activity.