Velnacrine thiaanalogues as potential agents for treating Alzheimer's disease

Bioorg Med Chem. 2001 Nov;9(11):2921-8. doi: 10.1016/s0968-0896(01)00171-7.


The only therapeutic drugs for combating dementia disease are acetylcholine esterase inhibitors (AChEI). However, the use of tacrine, the first AChEI to be launched as an Alzheimer's disease (AD) drug, has been limited by serious side effects. Therefore, efforts to search for more potent and selective inhibitors of AChE still remain highly significant in the therapeutic treatment of AD. In this work we modified the cyclohexyl ring of velnacrine, a less toxic analogue of tacrine, by synthesizing a series of thiopyranoquinolines in which the C-3 methylene unit was replaced by a sulphur atom. The anti-AChE data show that the activity was maintained with the bioisosteric substitution carried out. The introduction of a chlorine atom at different positions of the aromatic ring resulted in an array of different activities. In an attempt to understand the different behaviours displayed by the chlorine-substituted derivatives, a molecular docking study was performed.

MeSH terms

  • Administration, Oral
  • Alzheimer Disease / drug therapy*
  • Animals
  • Avoidance Learning / drug effects
  • Blood Cells / enzymology
  • Chlorine
  • Cholinesterase Inhibitors / chemical synthesis*
  • Cholinesterase Inhibitors / pharmacology
  • Cholinesterase Inhibitors / toxicity
  • Humans
  • Inhibitory Concentration 50
  • Male
  • Mice
  • Models, Molecular
  • Rats
  • Rats, Sprague-Dawley
  • Structure-Activity Relationship
  • Sulfur
  • Survival Rate
  • Tacrine / analogs & derivatives*
  • Tacrine / chemical synthesis
  • Tacrine / pharmacology*
  • Tacrine / toxicity


  • Cholinesterase Inhibitors
  • Chlorine
  • Tacrine
  • Sulfur
  • velnacrine