Design, synthesis, and biological evaluation of AT1 angiotensin II receptor antagonists based on the pyrazolo[3,4-b]pyridine and related heteroaromatic bicyclic systems

J Med Chem. 2008 Apr 10;51(7):2137-46. doi: 10.1021/jm7011563. Epub 2008 Mar 5.

Abstract

Novel AT 1 receptor antagonists bearing the pyrazolo[3,4- b]pyridine bicyclic heteroaromatic system (or structurally related moieties) were designed and synthesized as the final step of a large program devoted to the development of new antihypertensive agents and to the understanding of the molecular basis of their pharmacodynamic and pharmacokinetic properties. The preliminary pharmacological characterization revealed nanomolar AT 1 receptor affinity for several compounds of the series and a potent antagonistic activity in isolated rabbit aortic strip functional assay for 7c and 8a. These results stimulated the study of the biopharmaceutical properties of some selected compounds, which were found to be characterized by a permeability from medium to high. Remarkably, the least permeable 7c showed both permeability and oral bioavailability (80%) higher than losartan, but its terminal half-life was shorter. These results suggest that the permeability is not a limiting factor in the pharmacokinetics of these AT 1 receptor antagonists.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin II Type 1 Receptor Blockers* / chemical synthesis
  • Angiotensin II Type 1 Receptor Blockers* / chemistry
  • Angiotensin II Type 1 Receptor Blockers* / pharmacology
  • Animals
  • Aorta, Thoracic / drug effects
  • Bridged Bicyclo Compounds, Heterocyclic* / chemical synthesis
  • Bridged Bicyclo Compounds, Heterocyclic* / chemistry
  • Bridged Bicyclo Compounds, Heterocyclic* / pharmacology
  • Caco-2 Cells
  • Cell Membrane Permeability / drug effects
  • Crystallography, X-Ray
  • Drug Design
  • Humans
  • Intestinal Mucosa / drug effects
  • Male
  • Models, Molecular
  • Molecular Structure
  • Pyrazoles* / chemical synthesis
  • Pyrazoles* / chemistry
  • Pyrazoles* / pharmacology
  • Pyridines* / chemical synthesis
  • Pyridines* / chemistry
  • Pyridines* / pharmacology
  • Rabbits
  • Rats
  • Rats, Wistar
  • Receptor, Angiotensin, Type 1 / drug effects*
  • Stereoisomerism
  • Structure-Activity Relationship

Substances

  • Angiotensin II Type 1 Receptor Blockers
  • Bridged Bicyclo Compounds, Heterocyclic
  • Pyrazoles
  • Pyridines
  • Receptor, Angiotensin, Type 1
  • pyrazolo(3,4-b)pyridine