Radiosynthesis of novel N- 18 F-labeled 18 F-FHex-α-l-Glu and 18 F-FHex-β-Glu.

N-F-18-labeled amino acids are important substitutes for new positron emission tomography (PET) imaging tracers complementing the deficiency of F-18-fluorodeoxyglucose (F-18-FDG). In this work, two novel N-6-F-18-alkyl amino acid imaging agents, F-18-FHex-alpha-l-Glu and F-18-FHex-beta-Glu, were designed and synthesized as potential probes for PET imaging of tumors. F-18-FHex-alpha-l-Glu was synthesized using the precursor 6 from F-18-F- with the yield of 16 +/- 4% (n = 5, uncorrected) within about 50 minutes. The specific activity was 14.5 GBq/mu mol, and the radiochemical purity was more than 95%. F-18-FHex-beta-Glu was synthesized using the precursor 12 based on F-18-F- with the yield of 11 +/- 3% (n = 3, uncorrected) in about 60 minutes. The specific activity was 9.1 GBq/mu mol, and the radiochemical purity was more than 95%.