A stepwise dechlorination/cross-coupling strategy to diversify the vancomycin 'in-chloride'

Area of Science:

• Medicinal Chemistry
• Organic Synthesis
• Antibiotic Research

Background:

• Vancomycin is a critical antibiotic for treating Gram-positive bacterial infections.
• Development of vancomycin analogues is crucial to combat rising antibiotic resistance.
• Modifications at the 6c-Cl position of vancomycin are challenging yet promising for new derivatives.

Purpose of the Study:

• To develop a facile two-step protocol for functionalizing the 6c-Cl position of vancomycin.
• To synthesize novel 2c-dechloro-6c-functionalized vancomycin derivatives.
• To evaluate the antibiotic activity of these novel derivatives against resistant and susceptible bacterial strains.

Main Methods:

• A two-step protocol involving dechlorination followed by cross-coupling was employed.
• Optimization of cross-coupling conditions for the unreactive 6c-Cl group.
• Synthesis and purification of 2c-dechloro-6c-functionalized vancomycin derivatives.
• Biological evaluation of synthesized compounds against various bacterial strains.

Main Results:

• Efficient cross-coupling conditions were established for the 6c-Cl position, achieving high conversion.
• A library of 2c-dechloro-6c-functionalized vancomycin derivatives was successfully synthesized.
• Biological testing demonstrated varying antibiotic activities, highlighting steric sensitivity in vancomycin's binding pocket.

Conclusions:

• The developed two-step protocol provides rapid access to diverse vancomycin analogues.
• The steric sensitivity of vancomycin's binding pocket influences antibiotic activity.
• This work contributes to the development of new strategies against vancomycin-resistant bacteria.