SYNTHESIS OF ~(11)C-LABELED URACIL DERIVATIVE FOR A PET TRACER TARGETING THYMIDINE PHOSPHORYLASE

摘要

The expression of thymidine phosphorylase (TP) is closely associated with angiogenesis in tumors. For developing a TP-expression-based positron emission tomography (PET) radiotracer for diagnosis and prognosis of cancer chemotherapy, we synthesized a novel ~(11)C-labeled oxoimidazolidinylmethyluracil ([~(11)C]-2a), which was designed on the basis of one of the most potent inhibitors, 5-bromo-6-[(2-iminoimidazolidinyl)-methyl]uracil hydrobromide (5BIMU), through a ring closure reaction of [~(11)C]phos gene with a developed diamine precursor (1a). After purification by HPLC, the total synthesis was accomplished in just 23 min after bombardment, and the yield was 1653 MBq at the end of synthesis (EOS).