Diazo compounds for the bioreversible esterification of proteins

Area of Science:

• Biochemistry
• Organic Chemistry
• Chemical Biology

Background:

• Carboxylic acids are common functional groups in biomolecules.
• Modifying carboxylic acids can alter protein properties and function.
• Developing efficient and selective chemical modification methods is crucial.

Purpose of the Study:

• To develop a novel method for converting carboxylic acids to esters in an aqueous environment.
• To investigate the reactivity of a specific diazo compound with carboxylic acids.
• To explore the potential of this reaction for protein modification and prodrug development.

Main Methods:

• Reaction of carboxylic acids with a diazo compound in aqueous solution.
• Characterization of the resulting esters using analytical techniques.
• Application of the method to model proteins containing carboxylic acid groups.
• Assessment of the hydrolysis of the modified protein esters by cellular esterases.

Main Results:

• The diazo compound efficiently converted carboxylic acids to esters in water.
• The basicity of the diazo compound was found to be critical for efficient esterification without hydrolysis.
• The reaction was successfully applied to carboxylic acid groups on proteins.
• The protein esters were hydrolyzed by human cellular esterases, regenerating the carboxyl groups.

Conclusions:

• A new aqueous method for esterifying carboxylic acids using a diazo compound has been developed.
• This method offers a controllable way to modify proteins.
• The reversible nature of the modification, via ester hydrolysis, opens possibilities for protein prodrug strategies.