SPECT显像剂^(131)I-Nalepride的合成

Synthesis of SPECT Imaging Agent ～(131)I-Nalepride

5-碘-2,3-二甲氧基苯甲酸与(S)-1-烯丙基-2-氨甲基吡咯烷反应得到(S)-(–)-N-[(1-烯丙基-2-吡咯烷基)甲基]-2,3-二甲氧基-5-碘苯甲酰胺,与双三丁基锡反应得到标记前体(S)-(–)-N-[(1-烯丙基-2-吡咯烷基)甲基]-2,3-二甲氧基-5-三丁基锡苯甲酰胺,总收率约70%。用双氧水法对标记前体进行碘[131I]标记得到SPECT显像剂131I-nalepride,标记率和放射化学纯度分别为95.4%和96.3%。

131↑I-Nalepride, a SPECT imaging agent was synthesized from the precursor, （S）-N-（（1- allylpyrrolidin-2-yl） methyl]-2,3-dimethoxy-5-tributylstannanylbenzaminde by using Na131↑I and oxidation in situ with hydrogen peroxide in 95.4% radiolabelled yield and 96.3% radiochemical purity. The precursor was synthesized from 2,3-dimethoxy-5-iodobenzoic acid via amidation with （S）- 1-allyl-2-aminomethylpyrrolidine to give the key intermediate （S） -N- E （1-allylpyrrolidin-2-yl） methyl]-2,3-dimethoxy-5-iodobenzamide, followed by reaction with （C4H9） 6Sn2 with an overall yield of about 70%.