Structure-activity relationship study between Ornithyl-Proline and Lysyl-Proline based tripeptidomimics as angiotensin-converting enzyme inhibitors

Bioorg Med Chem Lett. 2006 Apr 15;16(8):2117-21. doi: 10.1016/j.bmcl.2006.01.061. Epub 2006 Feb 7.


A designed library of tripeptidomimics of Ornithyl-Proline (Orn-Pro) and Lysyl-Proline (Lys-Pro) conjugated with various unnatural amino acids and carboxylic acid derived heterocyclics was synthesized and screened for possible inhibitors of angiotensin-converting enzyme (ACE). Among the tripeptidomimics 10[MTP-Orn-Pro], 11[HTP-Orn-Pro], 14[TA-Orn-Pro] and 20[BPA-Orn-Pro] showed prominent inhibition with IC50 values in micromolar concentrations. Structure-activity relationship study indicated that C3 side chain of Orn as compared to C4 side chain of Lys at P1' position was better suited to inhibit ACE, with propionic acid (C3) derived heterocyclics and unnatural amino acids.

MeSH terms

  • Angiotensin-Converting Enzyme Inhibitors / chemical synthesis*
  • Angiotensin-Converting Enzyme Inhibitors / pharmacology
  • Animals
  • Binding Sites
  • Cattle
  • Kidney / metabolism
  • Lysine / chemistry
  • Molecular Mimicry
  • Oligopeptides / chemical synthesis*
  • Oligopeptides / pharmacology
  • Ornithine / chemistry
  • Proline / analogs & derivatives*
  • Structure-Activity Relationship


  • Angiotensin-Converting Enzyme Inhibitors
  • Oligopeptides
  • Proline
  • Ornithine
  • Lysine