3,6-Diamino-4-(2-halophenyl)-2-benzoylthieno[2,3-b]pyridine-5-carbonitriles are selective inhibitors of Plasmodium falciparum glycogen synthase kinase-3

J Med Chem. 2013 Jan 10;56(1):264-75. doi: 10.1021/jm301575n. Epub 2012 Dec 27.


Plasmodium falciparum is the infective agent responsible for malaria tropica. The glycogen synthase kinase-3 of the parasite (PfGSK-3) was suggested as a potential biological target for novel antimalarial drugs. Starting from hit structures identified in a high-throughput screening campaign, 3,6-diamino-4-(2-halophenyl)-2-benzoylthieno[2,3-b]pyridine-5-carbonitriles were discovered as a new class of PfGSK-3 inhibitors. Being less active on GSK-3 homologues of other species, the title compounds showed selectivity in favor of PfGSK-3. Taking into account the X-ray structure of a related molecule in complex with human GSK-3 (HsGSK-3), a model was computed for the comparison of inhibitor complexes with the plasmodial and human enzymes. It was found that subtle differences in the ATP-binding pockets are responsible for the observed PfGSK-3 vs HsGSK-3 selectivity. Representatives of the title compound class exhibited micromolar IC₅₀ values against P. falciparum erythrocyte stage parasites. These results suggest that inhibitors of PfGSK-3 could be developed as potential antimalarial drugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / chemistry
  • Antimalarials / chemical synthesis*
  • Antimalarials / chemistry
  • Antimalarials / pharmacology
  • Crystallography, X-Ray
  • Glycogen Synthase Kinase 3 / antagonists & inhibitors*
  • Glycogen Synthase Kinase 3 / chemistry
  • High-Throughput Screening Assays
  • Humans
  • Molecular Docking Simulation
  • Nitriles / chemical synthesis*
  • Nitriles / chemistry
  • Nitriles / pharmacology
  • Parasitic Sensitivity Tests
  • Plasmodium falciparum / drug effects*
  • Plasmodium falciparum / enzymology
  • Protein Binding
  • Pyridines / chemical synthesis*
  • Pyridines / chemistry
  • Pyridines / pharmacology
  • Structure-Activity Relationship
  • Thiophenes / chemical synthesis*
  • Thiophenes / chemistry
  • Thiophenes / pharmacology


  • Antimalarials
  • Nitriles
  • Pyridines
  • Thiophenes
  • Adenosine Triphosphate
  • Glycogen Synthase Kinase 3