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Updated: Aug 5, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Activity Against ESKAPE Bacterial Pathogens of Pyrazole-Indol-Ruthenium(II) Complexes
Yahaira Cuenú-Ibargüen1,2, Andrés Restrepo-Acevedo1, Juan Felipe Zambrano-Bedoya1
1Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Ciudad de México 04510, Mexico.
Antibiotics (Basel, Switzerland)
|July 27, 2026
Summary
Ruthenium(II) complexes with NH-pyrazole-indole Schiff base ligands show significant antibacterial activity against antibiotic-resistant bacteria. Two complexes demonstrated superior efficacy against Staphylococcus aureus compared to Trimethoprim.
Area of Science:
- Coordination Chemistry
- Medicinal Chemistry
- Materials Science
Background:
- Schiff base ligands derived from NH-pyrazole-indole scaffolds are of interest for their coordination properties.
- Ruthenium complexes are explored for their potential therapeutic applications, including antimicrobial activity.
- Antibiotic resistance necessitates the development of novel antimicrobial agents.
Purpose of the Study:
- To synthesize and characterize novel Schiff base ligands and their ruthenium(II) complexes.
- To evaluate the antibacterial efficacy of these compounds against a panel of antibiotic-resistant bacteria, including ESKAPE pathogens.
- To investigate the structure-activity relationship, particularly the effect of methoxy group substitution on biological activity.
Main Methods:
- Synthesis of Schiff base ligands and ruthenium(II) complexes.
- Comprehensive structural characterization using IR, Raman, NMR, UV-Vis, ESI-MS, elemental analysis, and X-ray crystallography.
- Antibacterial assays including determination of Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC).
- Molecular docking studies to elucidate potential mechanisms of action.
Main Results:
- All four synthesized ruthenium(II) complexes exhibited notable antibacterial activity, while the free ligands were inactive.
- Compounds Ru3 and Ru4 showed significant activity against Staphylococcus aureus, surpassing Trimethoprim and comparable to Gentamicin.
- Molecular docking suggested that the complexes may act by binding to the active site of S. aureus PBP2a.
Conclusions:
- Ruthenium(II) complexes of NH-pyrazole-indole Schiff bases represent a promising class of novel antibacterial agents.
- The observed activity highlights the potential of these complexes in combating infections caused by antibiotic-resistant bacteria.
- Further investigation into their mechanism of action and therapeutic potential is warranted.
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