Novel amide and imidazole compounds as potent hematopoietic prostaglandin D2 synthase inhibitors

Bioorg Med Chem Lett. 2021 Feb 15:34:127759. doi: 10.1016/j.bmcl.2020.127759. Epub 2020 Dec 29.

Abstract

In seeking novel and potent small molecule hematopoietic prostaglandin D2 synthase (H-PGDS) inhibitors as potential therapies for PGD2-mediated diseases and conditions, we explored a series comprising multiple aryl/heteroaryl rings attached in a linear arrangement. Each compound incorporates an amide or imidazole "linker" between the pyrimidine or pyridine "core" ring and the "tail" ring system. We synthesized and screened twenty analogs by fluorescence polarization binding assay, thermal shift assay, glutathione S-transferase inhibition assay, and a cell-based assay measuring suppression of LPS-induced PGD2 stimulation. Amide analogs show ten-fold greater shift in the thermal shift assay in the presence of glutathione (GSH) versus the same assay run in the absence of GSH. The imidazole analogs did not produce a significant change in thermal shift between the two assay conditions, suggesting a possible stabilization effect of the amide linker in the synthase-GSH-inhibitor complex. Imidazole analog 23, (KMN-010034) demonstrates superior potency across the in vitro assays and good in vitro metabolic stability in both human and guinea pig liver microsomes.

Keywords: H-PGDS; Hematopoietic D(2) synthase; PGD(2); Prostaglandin D(2); SAR; Structure-activity-relationship.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amides / chemical synthesis
  • Amides / chemistry
  • Amides / pharmacology*
  • Animals
  • Dose-Response Relationship, Drug
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology*
  • Guinea Pigs
  • Humans
  • Imidazoles / chemical synthesis
  • Imidazoles / chemistry
  • Imidazoles / pharmacology*
  • Intramolecular Oxidoreductases / antagonists & inhibitors*
  • Intramolecular Oxidoreductases / metabolism
  • Lipocalins / antagonists & inhibitors*
  • Lipocalins / metabolism
  • Lipopolysaccharides / antagonists & inhibitors
  • Lipopolysaccharides / pharmacology
  • Microsomes, Liver / chemistry
  • Microsomes, Liver / metabolism
  • Molecular Structure
  • Structure-Activity Relationship

Substances

  • Amides
  • Enzyme Inhibitors
  • Imidazoles
  • Lipocalins
  • Lipopolysaccharides
  • imidazole
  • Intramolecular Oxidoreductases
  • prostaglandin R2 D-isomerase