(<i>R</i>)-<i>N</i>-Methyl-3-(3′-[<sup>18</sup>F]fluoropropyl)phenoxy)-3-phenylpropanamine (<sup>18</sup>F-MFP3) as a potential PET imaging agent for norepinephrine transporter
作者:Vivien L. Nguyen、Rama Pichika、Paayal H. Bhakta、Ritu Kant、Jogeshwar Mukherjee
DOI:10.1002/jlcr.1744
日期:——
A decline of norepinephrine transporter (NET) level is associated with several psychiatric and neurological disorders. Therefore positron emission tomography (PET) imaging agents are greatly desired to study the NET pathway. We have developed a C-fluoropropyl analog of nisoxetine: (R)-N-methyl-3-(3′-[18F]fluoropropyl)phenoxy)-3-phenylpropanamine (18F-MFP3) as a new potential PET radiotracer for NET with the advantage of the longer half-life of fluorine-18 (110 min compared with carbon-11 (20 min). Synthesis of (R)-N-methyl-3-(3′-fluoropropyl)phenoxy)-3-phenylpropanamine (MFP3) was achieved in five steps starting from (S)-N-methyl-3-ol-3-phenylpropanamine in approx. 3–5% overall yields. In vitro binding affinity of nisoxetine and MFP3 in rat brain homogenates labeled with 3H-nisoxetine gave Ki values of 8.02 nM and 23 nM, respectively. For radiosynthesis of 18F-MFP3, fluorine-18 was incorporated into a tosylate precursor, followed by the deprotection of the N-BOC-protected amine group with a 15% decay corrected yield in 2.5 h. Reverse-phase chromatographic purification provided 18F-MFP3 in specific activities of >2000 Ci/mmol. Fluorine-18 labeled 18F-MFP3 has been produced in modest radiochemical yields and in high specific activities. Evaluation of 18F-MFP3 in animal imaging studies is in progress in order to validate this new fluorine-18 radiotracer for PET imaging of NET. Copyright © 2010 John Wiley & Sons, Ltd.
去甲肾上腺素转运体(NET)水平的下降与多种精神和神经疾病有关。因此,正电子发射断层扫描(PET)成像剂是研究 NET 途径的最佳选择。我们开发了尼索西汀的 C-氟丙基类似物:(R)-N-甲基-3-(3′-[18F]氟丙基)苯氧基)-3-苯基丙胺(18F-MFP3),作为一种新的潜在的 NET PET 放射性示踪剂,其优势在于氟-18 的半衰期(110 分钟)长于碳-11(20 分钟)。(R)-N-甲基-3-(3′-氟丙基)苯氧基-3-苯基丙胺(MFP3)的合成从(S)-N-甲基-3-醇-3-苯基丙胺开始,分五个步骤完成,总产率约为 3-5%。用 3H -尼索西汀标记的尼索西汀和 MFP3 在大鼠脑匀浆中的体外结合亲和力 Ki 值分别为 8.02 nM 和 23 nM。在 18F-MFP3 的放射合成过程中,先将氟-18 加入对甲苯磺酸盐前体,然后对 N-BOC 保护的胺基团进行脱保护,2.5 小时内的衰减校正收率为 15%。反相色谱纯化后,18F-MFP3 的比活度大于 2000 Ci/mmol。氟-18 标记的 18F-MFP3 的放射化学收率和比活度都很高。目前正在动物成像研究中对 18F-MFP3 进行评估,以验证这种用于 NET PET 成像的新型氟-18 放射性示踪剂的有效性。Copyright © 2010 John Wiley & Sons, Ltd. All Rights Reserved.