1. Academic Validation
  2. 3-(2-Carboxyethyl)indole-2-carboxylic Acid Derivatives: Structural Requirements and Properties of Potent Agonists of the Orphan G Protein-Coupled Receptor GPR17

3-(2-Carboxyethyl)indole-2-carboxylic Acid Derivatives: Structural Requirements and Properties of Potent Agonists of the Orphan G Protein-Coupled Receptor GPR17

  • J Med Chem. 2018 Sep 27;61(18):8136-8154. doi: 10.1021/acs.jmedchem.7b01768.
Younis Baqi 1 Thanigaimalai Pillaiyar 2 Aliaa Abdelrahman 2 Olesja Kaufmann 2 Samer Alshaibani 2 Muhammad Rafehi 2 Saman Ghasimi 2 Rhalid Akkari 2 Kirsten Ritter 2 Katharina Simon 3 Andreas Spinrath 3 Evi Kostenis 3 Qiang Zhao 4 Meryem Köse 2 Vigneshwaran Namasivayam 2 Christa E Müller 2
Affiliations

Affiliations

  • 1 Department of Chemistry, Faculty of Science , Sultan Qaboos University , P.O. Box 36, 123 Muscat , Oman.
  • 2 PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Sciences Bonn (PSB), Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , 53121 Bonn , Germany.
  • 3 Institute of Pharmaceutical Biology, Section Molecular-, Cellular-, and Pharmacobiology, University of Bonn , Nußallee 6 , 53115 Bonn , Germany.
  • 4 CAS Key Laboratory of Receptor Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zuchongzhi Road, Pudong , Shanghai 201203 , China.
Abstract

The Orphan Receptor GPR17 may be a novel drug target for inflammatory diseases. 3-(2-Carboxyethyl)-4,6-dichloro-1 H-indole-2-carboxylic acid (MDL29,951, 1) was previously identified as a moderately potent GPR17 agonist. In the present study, we investigated the structure-activity relationships (SARs) of 1. Substitution of the indole 1-, 5-, or 7-position was detrimental. Only small substituents were tolerated in the 4-position while the 6-position accommodated large lipophilic residues. Among the most potent compounds were 3-(2-carboxyethyl)-1 H-indole-2-carboxylic acid derivatives containing the following substituents: 6-phenoxy (26, PSB-1737, EC50 270 nM), 4-fluoro-6-bromo (33, PSB-18422, EC50 27.9 nM), 4-fluoro-6-iodo (35, PSB-18484, EC50 32.1 nM), and 4-chloro-6-hexyloxy (43, PSB-1767, EC50 67.0 nM). (3-(2-Carboxyethyl)-6-hexyloxy-1 H-indole-2-carboxylic acid (39, PSB-17183, EC50 115 nM) behaved as a partial agonist. Selected potent compounds tested at human P2Y Receptor subtypes showed high selectivity for GPR17. Docking into a homology model of the human GPR17 and molecular dynamic simulation studies rationalized the observed SARs.

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