Synthesis of 1-[F-18]fluorodeoxyglucose: an unexpected rearrangement in the reaction of 2-O-methanesulfonyl-beta-D-mannopyranose with [F-18]fluoride

2-O-Methanesulfonyl-beta-D-mannose was reacted with kryptofix/K2CO3/[F-18]f luoride in CH3CN/THF (9:1) at 60 degrees C. Unexpectedly, a mixture of 1 al pha- and 1 beta-glucopyranosyl [F-18]fluoride (4 and 5, respectively) was o btained in 50% radiochemical yield (EOB); 2-[F-18]FDG was not detected. Mod ification of temperature, solvent or pH did riot result in the formation of 2-[F-18]FDG. Uptake of radioactivity in heart and brain of mice was signif icantly lower for 4 and 5 than for 2-[F-18]FDG, although 5 seems to pass th e blood-brain barrier. Uptake in bone was more pronounced for 4 than for 5 and negligible for 2-[F-18]FDG.