New antiprotozoal agents: Synthesis and biological evaluation of different 4-(7-chloroquinolin-4-yl) piperazin-1-yl)pyrrolidin-2-yl)methanone derivatives

Bioorg Med Chem Lett. 2017 Feb 1;27(3):460-465. doi: 10.1016/j.bmcl.2016.12.043. Epub 2016 Dec 18.

Abstract

In an endeavor to develop efficacious antiprotozoal agents 4-(7-chloroquinolin-4-yl) piperazin-1-yl)pyrrolidin-2-yl)methanone derivatives (5-14) were synthesized, characterized and biologically evaluated for antiprotozoal activity. The compounds were screened in vitro against the HM1: IMSS strain of Entamoeba histolytica and NF54 chloroquine-sensitive strain of Plasmodium falciparum. Among the synthesized compounds six exhibited promising antiamoebic activity with IC50 values (0.14-1.26μM) lower than the standard drug metronidazole (IC50 1.80μM). All nine compounds exhibited antimalarial activity (IC50 range: 1.42-19.62μM), while maintaining a favorable safety profile to host red blood cells. All the compounds were less effective as an antimalarial and more toxic (IC50 range: 14.67-81.24μM) than quinine (IC50: 275.6±16.46μM) against the human kidney epithelial cells. None of the compounds exhibited any inhibitory effect on the viability of Anopheles arabiensis mosquito larvae.

Keywords: Amoebiasis; Entamoeba histolytica; MTT-assay; Metronidazole; Plasmodium falciparum; Thioredoxin reductase.

MeSH terms

  • Antimalarials / chemistry
  • Antimalarials / pharmacology
  • Antiprotozoal Agents / chemical synthesis*
  • Antiprotozoal Agents / chemistry
  • Antiprotozoal Agents / pharmacology
  • Binding Sites
  • Cell Line
  • Cell Survival / drug effects
  • Chloroquine / chemistry*
  • Entamoeba histolytica / drug effects
  • Erythrocytes / drug effects
  • Humans
  • Inhibitory Concentration 50
  • Molecular Docking Simulation
  • Piperazine
  • Piperazines / chemistry*
  • Plasmodium falciparum / drug effects
  • Protein Structure, Tertiary
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / metabolism
  • Structure-Activity Relationship
  • Thioredoxin-Disulfide Reductase / chemistry
  • Thioredoxin-Disulfide Reductase / metabolism

Substances

  • Antimalarials
  • Antiprotozoal Agents
  • Piperazines
  • Protozoan Proteins
  • Piperazine
  • Chloroquine
  • Thioredoxin-Disulfide Reductase