18 F-Labeled indole-based analogs as highly selective radioligands for imaging sigma-2 receptors in the brain
作者:Liang Wang、Jiajun Ye、Yingfang He、Winnie Deuther-Conrad、Jinming Zhang、Xiaojun Zhang、Mengchao Cui、Jörg Steinbach、Yiyun Huang、Peter Brust、Hongmei Jia
DOI:10.1016/j.bmc.2017.05.019
日期:2017.7
We have designed and synthesized a series of indole-based sigma(2) receptor ligands containing 5,6-dimethoxyisoindoline or 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline as pharmacophore. In vitro competition binding assays showed that all ten ligands possessed low nanomolar affinity (K-i=1.79-5.23 nM) for sigma(2) receptors and high subtype selectivity (K-1(sigma(2))/K-1 (sigma(1)) = 56-708). Moreover, they showed high selectivity for sigma(2) receptor over the vesicular acetylcholine transporter (>1000-fold). The corresponding radiotracers [F-18]16 and [F-18]21 were prepared by an efficient one-pot, two-step reaction sequence with a home-made automated synthesis module, with 10-15% radiochemical yield and radiochemical purity of >99%. Both radiotracers showed high brain uptake and o-2 receptor binding specificity in mice. (C) 2017 Elsevier Ltd. All rights reserved.