Synthesis and structure-activity relationships of a novel series of non-peptide angiotensin II receptor binding inhibitors specific for the AT2 subtype

J Med Chem. 1991 Nov;34(11):3248-60. doi: 10.1021/jm00115a014.


Structure-activity relationships are reported for a novel class of 4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine-6-carboxylic acid derivatives that displace 125I-labeled angiotensin II from a specific subset of angiotensin II (Ang II) binding sites in rat adrenal preparations. This binding site is not the Ang II receptor mediating vascular contraction or aldosterone release, but, rather, is one whose function has not yet been fully elucidated. It has been identified in a number of tissues and has a similar affinity for Ang II and its peptide analogues as does the vascular receptor. The non-peptide compounds reported here are uniquely specific in displacing Ang II at this binding site and are inactive in antagonizing Ang II at the vascular receptor or in pharmacological assays measuring vascular effects. PD 123,319 (79), one of the most potent compounds, has an IC50 of 34 nM. Certain of these compounds may have utility in the definition and study of Ang II receptor subtypes.

MeSH terms

  • Adrenal Glands / drug effects
  • Adrenal Glands / metabolism
  • Angiotensin II / antagonists & inhibitors
  • Angiotensin II / metabolism
  • Angiotensin Receptor Antagonists
  • Animals
  • Binding Sites
  • Biphenyl Compounds / pharmacology
  • Imidazoles / pharmacology
  • Losartan
  • Pyridines / chemical synthesis*
  • Pyridines / pharmacology
  • Rabbits
  • Rats
  • Receptors, Angiotensin / drug effects*
  • Receptors, Angiotensin / metabolism
  • Stereoisomerism
  • Structure-Activity Relationship
  • Tetrazoles / pharmacology


  • Angiotensin Receptor Antagonists
  • Biphenyl Compounds
  • Imidazoles
  • Pyridines
  • Receptors, Angiotensin
  • Tetrazoles
  • Angiotensin II
  • Losartan