Two novel ligands for cerebral cannabinoid receptor (CB1), 1-(2,4-dichlorophenyl)-4-cyano-5-(4-methoxyphenyl)-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide (JHU75528) and 1-(2-bromophenyl)-4-cyano-5-(4-methoxyphenyl)-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide (JHU75575) have been synthesized. Both JHU75528 and JHU75575 display a combination of higher binding affinity and lower lipophilicity than those of Rimonabant (SR141716), a high affinity CB1 selective antagonist, and AM281, the only available ligand for emission tomography imaging of CB1 in human subjects. Radiolabeled [11C]JHU75528 and [11C]JHU75575 were prepared by reaction of [11C]methyl iodide with nor-methyl precursors. The average radiochemical yield, specific radioactivity, and radiochemical purity of [11C]JHU75528 were 16%, 235 GBq/µmol (6360 mCi/µmol), and 99%, respectively; those of [11C]JHU75575 were 8%, 196 GBq/µmol (5308 mCi/µmol), and 99%, respectively. Both ligands hold promise as PET radioligands for imaging CB1 receptor. Copyright © 2006 John Wiley & Sons, Ltd.
脑
大麻素受体(CB1)的两种新型
配体--1-(2、合成了 1-(2,4-二
氯苯基)-4-
氰基-5-(4-
甲氧基苯基)-N-(
哌啶-1-基)-1H-
吡唑-3-甲酰胺(JHU75528)和 1-(2-
溴苯基)-4-
氰基-5-(4-
甲氧基苯基)-N-(
哌啶-1-基)-1H-
吡唑-3-甲酰胺(JHU75575)。与高亲和力 CB1 选择性拮抗剂
利莫那班(SR141716)和唯一可用于人体 CB1 发射断层成像的
配体 AM281 相比,JHU75528 和 JHU75575 都具有更高的结合亲和力和更低的亲脂性。放射性标记的[11C]JHU75528和[11C]JHU75575是通过[11C]甲基
碘与非甲基前体反应制备的。[11C]JHU75528的平均放射
化学收率、比放射性和放射
化学纯度分别为16%、235 GBq/µmol(6360 mCi/µmol)和99%;[11C]JHU75575的平均放射
化学收率、比放射性和放射
化学纯度分别为8%、196 GBq/µmol(5308 mCi/µmol)和99%。这两种
配体有望成为成像 CB1 受体的 PET 放射
配体。Copyright © 2006 John Wiley & Sons, Ltd. All Rights Reserved.