An Eco-Friendly Method to Synthesize Potent Antimicrobial Tricyclic Flavonoids

Area of Science:

• Medicinal Chemistry
• Green Chemistry
• Antimicrobial Resistance

Background:

• The rise of multidrug-resistant microorganisms poses a significant global health threat.
• There is an urgent need for novel antimicrobial agents due to the dwindling supply of effective antibiotics.
• Traditional synthesis methods can be environmentally harmful, necessitating eco-friendly approaches.

Purpose of the Study:

• To achieve the green synthesis of novel iodine-substituted tricyclic flavonoids.
• To evaluate the in vitro antimicrobial and antifungal activities of these newly synthesized compounds.
• To identify lead compounds with potent activity against priority pathogens.

Main Methods:

• Green synthesis of iodine-substituted tricyclic flavonoids using HPW-SiO2 as an eco-friendly cyclization agent.
• Evaluation of in vitro antimicrobial activity using minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentrations.
• Testing against a panel of Gram-positive bacteria, Gram-negative bacteria, and fungal strains.

Main Results:

• All synthesized compounds exhibited potent inhibitory activity against tested microbial strains.
• Compound 5c showed the lowest MIC values against Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) at 0.12 µg/mL and 0.48 µg/mL, respectively.
• Compound 5d displayed the highest antifungal activity against Candida krusei (MIC = 3.9 µg/mL) and potent bactericidal/fungicidal activity.

Conclusions:

• The novel iodine-substituted tricyclic flavonoids demonstrate significant potential as new antimicrobial agents.
• These compounds are effective against various bacterial and fungal strains, including WHO-priority pathogens.
• The green synthesis approach offers an environmentally friendly route for developing novel antimicrobials.