Rapid and efficient synthesis of [~18F]fluoro-nicotinamides, [~18F]fluoroisonicotinamides and [~18F]fluorobenzamides as potential pet radiopharmaceuticals for melanoma imaging

摘要

In an attempt to simplify nucleophiiic radiofluorination reactions to be amenable for automation, a series of [~18F]fluoronicotinamides, [ F]fluoroisonicotinamides and [~18F]fluorobenzamides were synthesized using one-step synthetic approach involving displacement reactions on trimethylammonium-nicotinamide, trimethylammonium-isonicotinamide and trimethylammonium-benzamide precursors. Based on starting [~18F]-fiuoride, radiochemical yields and purities were found to be greater than 90 and 97%, respectively, within 20 min synthesis time and, without high-performance liquid chromatography purification. This synthetic approach holds great promise as a rapid and simple method for the automated radiofluorination of [~18F]fluoronicotinamides, [~18F]fluoroisonicotinamides and [~18F]fluorobenzamides with high radio-chemical yield and very short preparation time.