The Synthesis Of The Precursor Of 3'-deoxy-3'-[¹⁸F]fluorothymidine ([¹⁸F]FLT)

Positron emission tomography (PET) is a powerful medical imaging method for measuring the distribution of the positron emitter in the human body by co-incidence of the annihilation photons resulting from positron decay. One of the positron emitting isotopes is fluorine-18 that is often used as a substitute for hydrogen in organic molecules with a half-life of 110 minutes, which allows complex synthesis and detailed imaging studies.3'-deoxy-3'-[18F]fluorothymidine([18F]FLT) appears to be the most promising radiopharmaceutical. It is under clinical evaluation as a metabolic probe for imaging cell proliferation in vivo using positron emission tomography(PET).In order to improve the [18F]FLT production, according to the reported synthetic route, BATH, DMTThy, 3'-O-mesyl-thymidine derivative and its pyrimidine ring N-BOC-protected analogue as precursors for [18F]FLT were synthesized. The reaction conditions and results were also described in this study.In addition, the fluorination of the precursors was also discussed.