4-Aryl Pyrrolidines as a Novel Class of Orally Efficacious Antimalarial Agents. Part 1: Evaluation of 4-Aryl- N-benzylpyrrolidine-3-carboxamides

J Med Chem. 2019 Apr 11;62(7):3503-3512. doi: 10.1021/acs.jmedchem.8b01972. Epub 2019 Mar 22.


Identification of novel chemotypes with antimalarial efficacy is imperative to combat the rise of Plasmodium species resistant to current antimalarial drugs. We have used a hybrid target-phenotype approach to identify and evaluate novel chemotypes for malaria. In our search for drug-like aspartic protease inhibitors in publicly available phenotypic antimalarial databases, we identified GNF-Pf-4691, a 4-aryl- N-benzylpyrrolidine-3-carboxamide, as having a structure reminiscent of known inhibitors of aspartic proteases. Extensive profiling of the two terminal aryl rings revealed a structure-activity relationship in which relatively few substituents are tolerated at the benzylic position, but the 3-aryl position tolerates a range of hydrophobic groups and some heterocycles. Out of this effort, we identified (+)-54b (CWHM-1008) as a lead compound. 54b has EC50 values of 46 and 21 nM against drug-sensitive Plasmodium falciparum 3D7 and drug-resistant Dd2 strains, respectively. Furthermore, 54b has a long half-life in mice (4.4 h) and is orally efficacious in a mouse model of malaria (qd; ED99 ∼ 30 mg/kg/day). Thus, the 4-aryl- N-benzylpyrrolidine-3-carboxamide chemotype is a promising novel chemotype for malaria drug discovery.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Antimalarials / administration & dosage
  • Antimalarials / chemistry
  • Antimalarials / pharmacology*
  • Biological Availability
  • Disease Models, Animal
  • Drug Evaluation, Preclinical
  • Malaria / drug therapy
  • Mice
  • Microsomes, Liver / drug effects
  • Pyrrolidines / administration & dosage
  • Pyrrolidines / chemistry
  • Pyrrolidines / pharmacology*
  • Structure-Activity Relationship


  • Antimalarials
  • Pyrrolidines