A facile permethylation of cord factor

Area of Science:

• Lipid chemistry
• Carbohydrate chemistry
• Mycobacterial cell wall analysis

Background:

• Cord factor (trehalose-6,6 -dimycolates) is a crucial component of the mycobacterial cell envelope.
• Understanding its chemical structure and properties is vital for developing new anti-mycobacterial strategies.
• Accurate structural elucidation requires reliable chemical modification techniques.

Purpose of the Study:

• To develop a robust method for the permethylation of cord factor.
• To confirm the 6,6 -dimycolate structure of cord factor using permethylation.
• To investigate the potential for acyl migration during the permethylation process.

Main Methods:

• Per} methylation of small quantities of cord factor using methyl iodide (CH3I) and sodium hydride (NaH)-oil dispersion.
• Utilizing anhydrous diethyl ether/dimethylformamide mixtures as solvents.
• Employing molecular sieve for efficient reaction conditions.
• Hydrolysis of permethylated products for structural analysis.

Main Results:

• Cord factor (trehalose-6,6 -dimycolates) was permethylated with high yield and quantitative recovery.
• Hydrolysis confirmed the 6,6 -dimycolate structure of permethylated cord factor from different sources.
• Experiments with a model compound (4-palmitoyl glucose) indicated a lack of acyl migration.

Conclusions:

• A reliable and efficient method for permethylating cord factor has been established.
• The established method confirms the 6,6 -dimycolate structure of cord factor.
• The findings suggest that acyl migration is not a significant issue in this permethylation system, facilitating accurate structural studies.