Azole endothelin antagonists. 3. Using delta log P as a tool to improve absorption

J Med Chem. 1996 Feb 16;39(4):982-91. doi: 10.1021/jm9505932.

Abstract

The oral absorption profile of a family of azole-based ET(A)-selective antagonists has been improved through a rational series of structural modifications which were suggested by analysis of the physicochemical parameter delta log P. Comparison of urea 2 with a series of well-absorbed compounds using delta log P analysis suggested that 2 has an excess capacity for forming hydrogen bonds with solvent. A series of urea modifications were explored as a means of reducing H-bonding capacity while maintaining affinity for the ET(A)-receptor. The correlation between delta log P values and absorption in an intraduodenal (id) bioavailability model was good; this strategy uncovered replacements for each of the urea NH groups which simultaneously improve both potency and drug absorption. A combination of these optimized modifications produces carbamate 16h, a highly-selective ET(A) antagonist with a potency/bioavailability profile consistent with an oral route of administration.

Publication types

  • Comparative Study

MeSH terms

  • Administration, Oral
  • Animals
  • Azepines / pharmacokinetics
  • Azoles / chemical synthesis*
  • Azoles / chemistry
  • Azoles / pharmacokinetics*
  • Drug Design
  • Endothelin Receptor Antagonists*
  • Hydrogen Bonding
  • Indicators and Reagents
  • Indoles / pharmacokinetics
  • Injections, Intravenous
  • Intestinal Absorption*
  • Kinetics
  • Male
  • Metabolic Clearance Rate
  • Models, Biological
  • Rats
  • Rats, Sprague-Dawley
  • Receptor, Endothelin A
  • Receptors, Endothelin / metabolism
  • Structure-Activity Relationship

Substances

  • Azepines
  • Azoles
  • Endothelin Receptor Antagonists
  • Indicators and Reagents
  • Indoles
  • Receptor, Endothelin A
  • Receptors, Endothelin
  • FR 139317