S-Euglobals: biomimetic synthesis, antileishmanial, antimalarial, and antimicrobial activities

Bioorg Med Chem. 2008 Feb 1;16(3):1328-36. doi: 10.1016/j.bmc.2007.10.055. Epub 2007 Oct 22.

Abstract

Several new euglobal analogues (named as S-euglobals) were synthesized from phloroglucinol via a biomimetic three-component reaction involving Knoevenagel condensation followed by [4+2]-Diels-Alder cycloaddition with monoterpene. Newly synthesized euglobal analogues involve monoterpenes that have not yet been encountered in natural euglobals. S-Euglobals along with previously synthesized robustadial A and B were evaluated for in vitro antileishmanial, antimalarial, antimicrobial, and cytotoxic activities. Out of 16, nine analogues were found to exhibit antileishmanial activity against Leishmania donovani promastigotes. Analogue 7 was the most potent with IC(50) of 2.4 microg/mL and IC(90) of 8 microg/mL, followed by analogues 8 and 11 (IC(50) 5.5 and 9.5 microg/mL). Antileishmanial activity of robustadial A (5) and B (6) was moderate with IC(50) of 20 and 16 microg/mL, respectively. Robustadial A and B and S-euglobal 8 exhibited weak antimalarial activity against Plasmodium falciparum (IC(50) of 2.7-4.76 microg/mL). Few of the euglobal analogues showed antibacterial activity against methicillin-resistant Staphylococcus aureus. Amongst these, analogue 11 was the most potent with IC(50) of 1.0 microg/mL and MIC of 5.0 microg/mL. Most of the compounds were not cytotoxic up to 25 microg/mL in a panel of cell lines consisting of both cancer (SK-MEL, KB, BT-549, and SK-OV-3) as well as non-cancer kidney (Vero and LLC-PK11) cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / chemical synthesis
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Antiprotozoal Agents / chemical synthesis
  • Antiprotozoal Agents / chemistry
  • Antiprotozoal Agents / pharmacology*
  • Biomimetic Materials / chemical synthesis
  • Biomimetic Materials / chemistry
  • Biomimetic Materials / pharmacology*
  • Leishmania donovani / drug effects
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Mycobacterium avium Complex / drug effects
  • Phloroglucinol / analogs & derivatives
  • Phloroglucinol / chemical synthesis
  • Phloroglucinol / chemistry
  • Phloroglucinol / pharmacology*
  • Plasmodium falciparum / drug effects
  • Staphylococcus aureus / drug effects
  • Structure-Activity Relationship
  • Terpenes / chemical synthesis*
  • Terpenes / chemistry
  • Terpenes / pharmacology*

Substances

  • Anti-Bacterial Agents
  • Antiprotozoal Agents
  • Terpenes
  • Phloroglucinol