1. Academic Validation
  2. Conformationally restricted κ-opioid receptor agonists: Synthesis and pharmacological evaluation of diastereoisomeric and enantiomeric decahydroquinoxalines

Conformationally restricted κ-opioid receptor agonists: Synthesis and pharmacological evaluation of diastereoisomeric and enantiomeric decahydroquinoxalines

  • Bioorg Med Chem Lett. 2015 Nov 15;25(22):5326-30. doi: 10.1016/j.bmcl.2015.09.040.
Peter Molenveld 1 Renaud Bouzanne des Mazery 1 Geert Jan Sterk 1 Roy P M Storcken 1 Reshma Autar 1 Bram van Oss 1 Richard N S van der Haas 1 Roland Fröhlich 2 Dirk Schepmann 3 Bernhard Wünsch 3 Michael Soeberdt 4
Affiliations

Affiliations

  • 1 Mercachem, Kerkenbos 1013, NL-6546 BB Nijmegen, The Netherlands.
  • 2 Organisch-Chemisches Institut der Universität Münster, Corrensstraße 40, D-48149 Münster, Germany.
  • 3 Institut für Pharmazeutische und Medizinische Chemie der Universität Münster, Corrensstraße 48, D-48149 Münster, Germany.
  • 4 Dr. August Wolff GmbH & Co. KG Arzneimittel, Sudbrackstraße 56, D-33611 Bielefeld, Germany. Electronic address: [email protected].
Abstract

All diastereoisomeric decahydroquinoxalines representing conformationally restricted analogs of κ agonists U-50,488 and GR-89,696 have been prepared. Cis/trans configured compound 7 is by far the highest binding diastereoisomer with a Ki of 0.35 nM. Racemates 4, 6, and 7 were separated into enantiomers. (+)-(4aR,5S,8aS)-Configured enantiomer 7b was identified as a high affinity (Ki=0.25 nM) κ ligand with high selectivity over μ and δ receptors. It acts as full agonist with an EC50 value of 2.0 nM in the [(35)S]GTPγS assay, while enantiomer 7a showed an EC50 value of 1000 nM.

Keywords

Decahydroquinoxalines; Diastereoisomers; Hydrogenation; Relationship between configuration and κ affinity; Resolution of enantiomers; SAR; κ agonists; κ-Opioid receptor.

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