Synthesis of 3'-deoxy-3'-[~(18)F]fluoro-l-beta-D-xylofurano-syluracil ([~(18)F]-FMXU) for PET

摘要

The synthesis of a pyrimidine analog, 3'-deoxy-3'-[~(18)F]-fluoro-l-beta-D-xylofuranosylur-acil ([~(18)F]-FMXU) is reported. 5-Methyluridine 1 was converted to its di-methoxytrityl derivatives 2 and 3 as a mixture. After separation the 2', 5'-di-methoxytrityluridine 2 was converted to its 3'-triflate 4 followed by derivatization to the respective N~3-t-Boc product 5. The triflate 5 was reacted with tetrabutylammo-nium[~(18)F]nuoride to produce 6, which by acid hydrolysis yielded compound 7. The crude preparation was purified by HPLC to obtain the desired product [~(18)F]-FMXU. The radiochemical yields were 25-40% decay corrected (d. c.) with an average of 33% in four runs. Radiochemical purity was >99% and specific activity was >74GBq/ mumol at the end of synthesis (EOS). The synthesis time was 67-75 min from the end of bombardment (EOB).