Bicyclic [3.3.0]-Octahydrocyclopenta[c]pyrrolo Antagonists of Retinol Binding Protein 4: Potential Treatment of Atrophic Age-Related Macular Degeneration and Stargardt Disease

J Med Chem. 2015 Aug 13;58(15):5863-88. doi: 10.1021/acs.jmedchem.5b00423. Epub 2015 Aug 4.

Abstract

Antagonists of retinol-binding protein 4 (RBP4) impede ocular uptake of serum all-trans retinol (1) and have been shown to reduce cytotoxic bisretinoid formation in the retinal pigment epithelium (RPE), which is associated with the pathogenesis of both dry age-related macular degeneration (AMD) and Stargardt disease. Thus, these agents show promise as a potential pharmacotherapy by which to stem further neurodegeneration and concomitant vision loss associated with geographic atrophy of the macula. We previously disclosed the discovery of a novel series of nonretinoid RBP4 antagonists, represented by bicyclic [3.3.0]-octahydrocyclopenta[c]pyrrolo analogue 4. We describe herein the utilization of a pyrimidine-4-carboxylic acid fragment as a suitable isostere for the anthranilic acid appendage of 4, which led to the discovery of standout antagonist 33. Analogue 33 possesses exquisite in vitro RBP4 binding affinity and favorable drug-like characteristics and was found to reduce circulating plasma RBP4 levels in vivo in a robust manner (>90%).

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bridged Bicyclo Compounds / chemistry
  • Bridged Bicyclo Compounds / pharmacokinetics
  • Bridged Bicyclo Compounds / therapeutic use*
  • Dogs
  • Geographic Atrophy / drug therapy*
  • Humans
  • Macular Degeneration / congenital*
  • Macular Degeneration / drug therapy
  • Madin Darby Canine Kidney Cells
  • Pyrroles / chemistry
  • Pyrroles / pharmacokinetics
  • Pyrroles / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • Retinol-Binding Proteins, Plasma / antagonists & inhibitors*
  • Retinol-Binding Proteins, Plasma / metabolism
  • Stargardt Disease
  • Structure-Activity Relationship

Substances

  • Bridged Bicyclo Compounds
  • Pyrroles
  • RBP4 protein, human
  • Retinol-Binding Proteins, Plasma