Discovery of further pyrrolidine trans-lactams as inhibitors of human neutrophil elastase (HNE) with potential as development candidates and the crystal structure of HNE complexed with an inhibitor (GW475151)

J Med Chem. 2002 Aug 29;45(18):3878-90. doi: 10.1021/jm020881f.


Described herein is a modern approach to the rapid preparation and evaluation of compounds as potential back-up drug candidates. GW311616A, 1, a derivative of pyrrolidine trans-lactams, has previously been described as a potent, orally active inhibitor of human neutrophil elastase (HNE) for the treatment of respiratory disease. These properties made it a suitable candidate for development. Described here is the discovery of three further derivatives of pyrrolidine trans-lactams, which fulfill the criteria required for back-up candidates 28, 29, and 32. These include increased activity in inhibiting HNE in human whole blood (HWB) and comparable pharmacokinetic properties, in particular clearance, in two species. To provide a rapid assessment of clearance, cassette dosing in dog was used. Modern array techniques, including the synthesis of mixtures, were used to synthesize compounds rapidly. Having selected three potential compounds as back-up candidates, they were prepared as single enantiomers and profiled in in vitro and in vivo assays and evaluated pharmacokinetically in rat and dog. These compounds are highly potent and selective HNE inhibitors, with a prolonged pharmacodynamic action. Pharmacokinetically, these compounds are comparable with 1 while they are more potent in HWB. Compound 28, however, has a higher clearance. One of these compounds, 32, was cocrystallized with HNE, and features of this structure are described and compared with the cocrystal structure of 1 in porcine pancreatic elastase.

MeSH terms

  • Animals
  • Combinatorial Chemistry Techniques
  • Crystallography, X-Ray
  • Dogs
  • Enzyme Inhibitors / chemical synthesis*
  • Enzyme Inhibitors / pharmacokinetics
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Lactams / chemical synthesis*
  • Lactams / pharmacokinetics
  • Lactams / pharmacology
  • Leukocyte Elastase / antagonists & inhibitors*
  • Leukocyte Elastase / blood
  • Leukocyte Elastase / chemistry
  • Male
  • Models, Molecular
  • Molecular Structure
  • Pyrroles / chemical synthesis*
  • Pyrroles / pharmacokinetics
  • Pyrroles / pharmacology
  • Pyrrolidines / chemical synthesis*
  • Pyrrolidines / pharmacokinetics
  • Pyrrolidines / pharmacology
  • Rats
  • Stereoisomerism
  • Structure-Activity Relationship
  • Sulfonamides / chemical synthesis*
  • Sulfonamides / pharmacokinetics
  • Sulfonamides / pharmacology
  • Swine


  • 3-isopropyl-1-methanesulfonyl-4-(2-pyrrolidin-1-ylmethyloxazole-4-carbonyl)hexahydropyrrolo(3,2-b)pyrrol-2-one
  • Enzyme Inhibitors
  • Lactams
  • Pyrroles
  • Pyrrolidines
  • Sulfonamides
  • Leukocyte Elastase

Associated data

  • PDB/1H1B