Syntheses, Biological Evaluation, and Molecular Modeling of 18F-Labeled 4-Anilidopiperidines as μ-Opioid Receptor Imaging Agents
摘要:
The synthesis, evaluation, and molecular modeling of a series of F-18-labeled 4-anilidopiperidines with high affinities for they-opioid receptor (mu-OR) are reported. On the basis of the high brain uptake and selective retention in brain regions that contain a high concentration of they-OR, combined with a good metabolic stability, [F-18]fluoro-pentyl carfentanil ([F-18]4) and 2-(+/-)[F-18]-fluoropropyl-sufentanil ([F-18]6) were selected as the lead compounds for further evaluation. The binding affinity to the human mu-OR was 0.74 and 0.13 nM for [F-18]4 and [F-18]6, respectively. In vitro autoradiography of [F-18]4 and [F-18]6 on rat brain sections produced patterns in accordance with the known distribution of mu-OR expression. Structure-activity relationships of the fluorinated compounds are discussed with respect to the interaction with an activated-state model of the mu-OR. Taken together, the in vivo and in vitro data indicate that [F-18]4 and [F-18]6 hold promise for studying they-opioid receptor in humans by means of positron emission tomography.
Syntheses, Biological Evaluation, and Molecular Modeling of 18F-Labeled 4-Anilidopiperidines as μ-Opioid Receptor Imaging Agents
摘要:
The synthesis, evaluation, and molecular modeling of a series of F-18-labeled 4-anilidopiperidines with high affinities for they-opioid receptor (mu-OR) are reported. On the basis of the high brain uptake and selective retention in brain regions that contain a high concentration of they-OR, combined with a good metabolic stability, [F-18]fluoro-pentyl carfentanil ([F-18]4) and 2-(+/-)[F-18]-fluoropropyl-sufentanil ([F-18]6) were selected as the lead compounds for further evaluation. The binding affinity to the human mu-OR was 0.74 and 0.13 nM for [F-18]4 and [F-18]6, respectively. In vitro autoradiography of [F-18]4 and [F-18]6 on rat brain sections produced patterns in accordance with the known distribution of mu-OR expression. Structure-activity relationships of the fluorinated compounds are discussed with respect to the interaction with an activated-state model of the mu-OR. Taken together, the in vivo and in vitro data indicate that [F-18]4 and [F-18]6 hold promise for studying they-opioid receptor in humans by means of positron emission tomography.
The synthesis of an F-18-labeled sufentanil analogue with apparent high mu-opioid receptor selectivity is reported. Intravenous injection of N-[4-(methoxymethyl)-1-[2-(2-thienyl)ethyl]-4-piperidinyl]-N-phenyl-2-(+/-)-[F-18]fluoropropan-amide in mice resulted in high brain uptake and a regional brain activity distribution corresponding to the mu-opioid receptor expression pattern. The developed ligand is a promising tracer for extended protocols in mu-opioid receptor mapping and quantitation with positron emission tomography. (c) 2005 Elsevier Ltd. All rights reserved.