Synthesis and biological evaluation of a radioiodinated spiropiperidine ligand as a potential σ1 receptor imaging agent
作者:Rui-Qin Chen、Yan Li、Qiu-Yan Zhang、Hong-Mei Jia、Winnie Deuther-Conrad、Dirk Schepmann、Jörg Steinbach、Peter Brust、Bernhard Wünsch、Bo-Li Liu
DOI:10.1002/jlcr.1777
日期:2010.7
We report the synthesis and evaluation of 1′-(4-[125I]iodobenzyl)-3H-spiro[isobenzofuran-1,4′-piperidine] ([125I]Spiro-I) as a potential SPECT tracer for imaging of σ1 receptors. [125I]Spiro-I was prepared in 55–65% isolated radiochemical yield, with radiochemical purity of >99%, via iododestannylation of the corresponding tributyltin precursor. In receptor binding studies, Spiro-I displayed low nanomolar affinity for σ1 receptors (σ1: Ki=2.75±0.12 nM; σ2: Ki=340 nM) and high subtype selectivity (σ2/σ1=124). Biodistribution in mice demonstrated relatively high concentration of radioactivity in organs known to contain σ1 receptors, including the lung, kidney, heart, spleen, and brain. Administration of haloperidol 5 min prior to injection of [125I]Spiro-I significantly reduced the concentration of radioactivity in the above-mentioned organs. These findings suggest that the binding of [125I]Spiro-I to σ1 receptors in vivo is specific. Copyright © 2010 John Wiley & Sons, Ltd.
我们报道了1′-(4-[125I]碘苄基)-3H-螺[异苯并呋喃-1,4′-哌啶]([125I]Spiro-I)作为潜在的单光子发射计算机断层显像(SPECT)示踪剂用于σ1受体成像的合成与评估。[125I]Spiro-I通过碘代脱锡化反应以55-65%的放射化学产率制备,放射化学纯度>99%。在受体结合研究中,Spiro-I显示出对σ1受体的低纳摩尔亲和力(σ1: Ki=2.75±0.12 nM; σ2: Ki=340 nM)和高亚型选择性(σ2/σ1=124)。在小鼠体内的生物分布显示,已知含有σ1受体的器官,包括肺、肾、心、脾和脑,放射活性浓度相对较高。在注射[125I]Spiro-I前5分钟给予氟哌啶醇显著降低了上述器官的放射活性浓度。这些发现表明,[125I]Spiro-I在体内对σ1受体的结合是特异性的。版权所有 © 2010 John Wiley & Sons, Ltd.