The Antimicrobial Properties of Pd^II - and Ru^II -pyta Complexes

Area of Science:

• Medicinal Chemistry
• Antimicrobial Drug Discovery
• Coordination Chemistry

Background:

• Antimicrobial resistance (AMR) poses a significant global health threat, driven by antibiotic overuse and a lack of new drug development.
• Metallodrugs represent an underexplored class of compounds with potential antimicrobial properties.
• The Community for Open Antimicrobial Drug Discovery (CO-ADD) initiative seeks novel compounds to address AMR.

Purpose of the Study:

• To evaluate the antimicrobial potential of novel palladium(II) and ruthenium(II) pyridyl-1,2,3-triazolyl complexes.
• To investigate the antifungal activity of these metallodrugs against drug-resistant pathogens.
• To assess the in vitro and in vivo efficacy and toxicity of promising candidates.

Main Methods:

• Synthesis and characterization of 18 Pd(II) and Ru(II) metal complexes.
• Antimicrobial susceptibility testing, including determination of Minimum Inhibitory Concentrations (MICs) against Candida glabrata.
• In vivo toxicity and efficacy studies using Galleria mellonella larvae models.

Main Results:

• Palladium(II) complexes, particularly Pd1, exhibited potent antifungal activity against Candida glabrata, with MICs ranging from 0.06 to 0.125 μg/mL.
• Ruthenium(II) complexes showed less potent activity compared to palladium complexes.
• In vivo studies in Galleria mellonella demonstrated that the tested compounds were non-toxic.

Conclusions:

• Palladium(II)-pyridyl-1,2,3-triazolyl complexes are effective antifungal agents with significant potential for combating Candida glabrata infections.
• These metallodrugs offer a promising avenue for developing new antimicrobial therapies against resistant pathogens.
• Further research into Pd(II)-based metallodrugs is warranted for antimicrobial drug discovery.