The first potent inhibitors for human glutaminyl cyclase: synthesis and structure-activity relationship

J Med Chem. 2006 Jan 26;49(2):664-77. doi: 10.1021/jm050756e.


The first effective inhibitors for human glutaminyl cyclase (QC) are described. The structures are developed by applying a ligand-based optimization approach starting from imidazole. Screening of derivatives of that heterocycle led to compounds of the imidazol-1-yl-alkyl thiourea type as a lead scaffold. A library of thiourea derivatives was synthesized, resulting in an inhibitory improvement by 2 orders of magnitude, leading to 1-(3-(1H-imidazol-1-yl)propyl)-3-(3,4-dimethoxyphenyl)thiourea as a potent inhibitor. Systematic exploitation of the scaffold revealed a strong impact on the inhibitory efficacy and resulted in the development of imidazole-propyl-thioamides as another new class of potent inhibitors. A flexible alignment of the most potent compounds of the thioamide and thiourea class and a QC substrate revealed a good match of characteristic features of the molecules, which suggests a similar binding mode of both inhibitors and the substrate to the active site of QC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoacyltransferases / antagonists & inhibitors*
  • Aminoacyltransferases / chemistry
  • Chelating Agents / chemical synthesis
  • Chelating Agents / chemistry
  • Humans
  • Imidazoles / chemical synthesis*
  • Imidazoles / chemistry
  • Models, Molecular
  • Structure-Activity Relationship
  • Thioamides / chemical synthesis*
  • Thioamides / chemistry
  • Thiourea / analogs & derivatives*
  • Thiourea / chemical synthesis
  • Thiourea / chemistry
  • Zinc / chemistry


  • 1-(3-(1H-imidazol-1-yl)propyl)-3-(3,4,5-trimethoxyphenyl)thiourea
  • Chelating Agents
  • Imidazoles
  • N-(3-(1H-imidazol-1-yl)propyl)-1-(3,4-dimethoxyphenyl)cyclopropanecarbothioamide
  • Thioamides
  • Aminoacyltransferases
  • glutaminyl-peptide cyclotransferase
  • Thiourea
  • Zinc