Synthesis of carbon-11-labeled tricyclic necroptosis inhibitors as new potential PET agents for imaging of tumor necrosis factor alpha (TNF-alpha).

Carbon-11-labeled tricyclic necroptosis inhibitors were first designed and synthesized as new potential PET agents for imaging of tumor necrosis factor alpha (TNF-alpha). The target tracers were prepared by O-[(11)C]methylation of their corresponding precursors using [(11)C]CH(3)OTf under basic conditions and isolated by a simplified SPE method in 50-60% radiochemical yields based on [(11)C]CO(2) and decay corrected to end of bombardment (EOB). The overall synthesis time from EOB was 15-20 min, the radiochemical purity was >99%, and the specific activity at end of synthesis (EOS) was 111-185 GBq/micromol.