Transforming rhinacanthin analogues from potent anticancer agents into potent antimalarial agents

J Med Chem. 2010 Feb 11;53(3):1211-21. doi: 10.1021/jm901545z.

Abstract

Twenty-six novel naphthoquinone aliphatic esters were synthesized by esterification of 1,4-naphthoquinone alcohols with various aliphatic acids. The 1,4-naphthoquinone alcohols were prepared from 1-hydroxy-2-naphthoic acid in nine steps with excellent yields. Twenty-four of the novel synthetic naphthoquinone esters showed significant antimalarial activity with IC(50) values in the range of 0.03-16.63 microM. The length of the aliphatic chain and the presence of C-2' substituents on the propyl chain affected the activity. Interestingly, compounds 31 and 37 showed very good antimalarial activity and were not toxic to normal Vero cells, and the PTI values of 31 (>1990.38) and 37 (1825.94) are excellent. Both 31 and 37 showed potent inhibition against P. falciparum 3D7 cyt bc(1) and no inhibition on rat cyt bc(1). They showed IC(50) values in the nanomolar range, providing full inhibition of cyt bc(1) with one molecule inhibitor bound per cyt bc(1) monomer at the Q(o) site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antimalarials / chemical synthesis
  • Antimalarials / chemistry
  • Antimalarials / pharmacology*
  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Cell Survival / drug effects
  • Chlorocebus aethiops
  • Electron Transport Complex III / antagonists & inhibitors
  • Erythrocytes / drug effects
  • Inhibitory Concentration 50
  • Malaria, Falciparum / drug therapy*
  • Malaria, Falciparum / parasitology
  • Male
  • Mitochondrial Membranes / drug effects
  • Naphthoquinones / chemistry*
  • Plasmodium falciparum / drug effects*
  • Rats
  • Rats, Wistar
  • Saccharomyces cerevisiae / growth & development
  • Structure-Activity Relationship
  • Vero Cells

Substances

  • Antimalarials
  • Antineoplastic Agents
  • Naphthoquinones
  • Electron Transport Complex III
  • 1,4-naphthoquinone