Molecular modeling study and synthesis of novel dicationic flexible triaryl guanidines and imidamides as antiprotozoal agents

Eur J Med Chem. 2011 Dec;46(12):5852-60. doi: 10.1016/j.ejmech.2011.09.047. Epub 2011 Oct 2.

Abstract

A new series of fourteen dicationic flexible triaryl bis-guanidines 3a,b, bis-N-substituted guanidines 7a,b and 8a,b as well as bis-imidamides 9-12a,b having a 1,3- or 1,4-diphenoxybenzene scaffold backbone were synthesized. The in vitro activity of the novel dications as antiprotozoal agents against Trypanosoma brucei rhodesiense (T.b.r.) and Plasmodium falciparum (P.f.) was assessed. Interestingly, six of the newly synthesized dications viz 3a,b, 7a,b and 8a,b were more active against P.f. than the reference drug pentamidine. Also, some of the dications showed moderate antitrypanosomal activity. Thermal melting analysis of the novel dications was performed to determine their ligand-DNA relative binding affinities. Finally, docking of the dications with an AT rich DNA oligonucleotide was executed to understand their binding mode with the minor groove.

MeSH terms

  • Amides / chemical synthesis
  • Amides / chemistry
  • Amides / pharmacology
  • Animals
  • Antiprotozoal Agents / chemical synthesis
  • Antiprotozoal Agents / chemistry*
  • Antiprotozoal Agents / pharmacology*
  • Cell Line
  • DNA / chemistry
  • DNA / metabolism
  • Guanidines / chemical synthesis
  • Guanidines / chemistry*
  • Guanidines / pharmacology*
  • Humans
  • Malaria, Falciparum / drug therapy
  • Models, Molecular
  • Parasitic Sensitivity Tests
  • Pentamidine / pharmacology
  • Plasmodium falciparum / drug effects*
  • Rats
  • Trypanosoma brucei rhodesiense / drug effects*
  • Trypanosomiasis, African / drug therapy

Substances

  • Amides
  • Antiprotozoal Agents
  • Guanidines
  • Pentamidine
  • DNA