Radiosynthesis of 3-(3-[18F]fluoropropoxy)-4-(benzyloxy)-N-[(1-dimethylaminocyclopentyl)methyl]-5-methoxybenzamide, a potential PET radiotracer for the glycine transporter GlyT-2
作者:Haibin Tian、Rebecca Vogel、Louis Amici、Gilles Tamagnan、Ronald M. Baldwin
DOI:10.1002/jlcr.1145
日期:2006.12
The recently described selective and potent GlyT2 antagonist, 4-benzyloxy-3,5-dimethoxy-N-[(1-dimethylaminocyclopentyl) methyl]benzamide (IC50=16 nM) provided an important additional tool to further characterize GlyT2 pharmacology. In order to identify an effective PET radioligand for in vivo assessment of the GlyT-2 transporter, 3-(3-[18F]fluoropropoxy)-4-(benzyloxy)-N-((1-dimethylaminocyclopentyl) methyl)-5-methoxybenzamide ([18F]3), a novel analog of 4-benzyloxy-3,5-dimethoxy-N-[(1-dimethylaminocyclopentyl) methyl]benzamide was synthesized using a one-pot, two-step method. The NCA radiofluorination of 1,3-propanediol di-p-tosylate in the presence of K2CO3 and Kryptofix-222 in acetonitrile gave 81% 3-[18F]fluoropropyl tosylate, which was subsequently coupled with 4-benzyloxy-3-hydroxy-5-methoxy-N-[(1-dimethylaminocyclopentyl) methyl]benzamide in the same reaction vessel. Solvent extraction and HPLC (Eclipse XDB-C8 column, 80/20/0.1 MeOH/H2O/Et3N, 3.0 ml/min) gave [18F]3 in 98.5% radiochemical purity. The radiochemical yield was determined to be 14.0–16.2% at EOS, and the specific activity was 1462±342 GBq/µmol. The time of synthesis and purification was 128 min. The final product was prepared as a sterile saline solution suitable for in vivo use. Copyright © 2006 John Wiley & Sons, Ltd.
最近描述的选择性和高效的GlyT2拮抗剂4-苄氧基-3,5-二甲氧基-N-[(1-二甲氨基环戊基)甲基]苯酰胺(IC50=16 nM)为进一步表征GlyT2药理学提供了一个重要的额外工具。为了寻找一种有效的PET放射配体用于GlyT-2转运体的体内评估,合成了3-(3-[18F]氟丙氧基)-4-(苄氧基)-N-((1-二甲氨基环戊基)甲基)-5-甲氧基苯酰胺([18F]3),这是4-苄氧基-3,5-二甲氧基-N-[(1-二甲氨基环戊基)甲基]苯酰胺的新型类似物,采用一步法两步合成。将1,3-丙二醇二-p-托烯-磺酸酯与K2CO3和Kryptofix-222在乙腈中进行NCA放射氟化,获得81%的3-[18F]氟丙基托烯-磺酸酯,随后与4-苄氧基-3-羟基-5-甲氧基-N-[(1-二甲氨基环戊基)甲基]苯酰胺在同一反应容器中偶联。溶剂提取和高效液相色谱(Eclipse XDB-C8柱,80/20/0.1 MeOH/H2O/Et3N,流速为3.0 ml/min)获得了98.5%的[18F]3放射化学纯度。放射化学产率在EOS时被测定为14.0–16.2%,特定活度为1462±342 GBq/μmol。合成和纯化所需时间为128分钟。最终产品以适合体内使用的无菌生理盐水溶液形式制备。版权 © 2006 John Wiley & Sons, Ltd.