Antibacterial profiling of abietane-type diterpenoids

Area of Science:

• Natural Products Chemistry
• Medicinal Chemistry
• Microbiology

Background:

• Abietic and dehydroabietic acids are diterpenes with known bioactivities.
• Increasing antimicrobial resistance and antibiotic shortages necessitate novel therapeutic agents.
• These compounds show potential antibacterial and antifungal properties.

Purpose of the Study:

• To synthesize novel abietic and dehydroabietic acid derivatives.
• To evaluate the in vitro antimicrobial activity of these derivatives against pathogenic microbes.
• To assess the in vitro cytotoxicity of the synthesized compounds against mammalian cells.

Main Methods:

• Synthesis of nine abietic and dehydroabietic acid derivatives with amino acid side chains.
• In vitro antimicrobial profiling against a panel of human pathogenic microbial strains.
• In vitro cytotoxicity evaluation against Balb/c 3T3 mammalian cells.

Main Results:

• Compound 10, methyl N-(abiet-8,11,13-trien-18-yl)-d-serinate, exhibited promising antimicrobial activity.
• MIC90 values for compound 10 were 60μg/mL against Staphylococcus aureus ATCC 25923 and 8μg/mL against MRSA, S. epidermidis, and S. mitis.
• Compound 10 showed an IC50 value of 45μg/mL against Balb/c 3T3 cells, indicating low cytotoxicity.

Conclusions:

• Novel abietic and dehydroabietic acid derivatives were successfully synthesized.
• Compound 10 demonstrates significant in vitro antimicrobial efficacy, particularly against Gram-positive pathogens including MRSA.
• The favorable cytotoxicity profile suggests potential therapeutic applications for compound 10 in combating antimicrobial resistance.