The synthesis of a triple tritiated isotopologue of the CRTh2 antagonist NVP-QAW039 (fevipiprant) with a specific activity >3 TBq/mmol is described. Key to the high specific activity is the methylation of a bench-stable dimeric disulfide precursor that is in situ reduced to the corresponding thiol monomer and methylated with [3H3]MeONos having per se a high specific activity. The high specific activity of the tritiated active pharmaceutical ingredient obtained by a build-up approach is discussed in the light of the specific activity usually to be expected if hydrogen tritium exchange methods were applied.
描述了比活性 >3 TBq/mmol 的 CRTh2 拮抗剂
NVP-QAW039(fevipiprant)的三重同位素体的合成。高比活性的关键是工作台稳定的二聚二
硫化物前体的甲基化,其原位还原为相应的
硫醇单体并用本身具有高比活性的[3H3]MeONos甲基化。根据如果应用氢氚交换方法通常预期的比活性来讨论通过累积方法获得的氚化活性药物成分的高比活性。