Chemoenzymatic construction of a four-component Ugi combinatorial library

Area of Science:

• Organic Chemistry
• Biocatalysis
• Medicinal Chemistry

Background:

• Multicomponent reactions (MCRs) like the Ugi reaction are powerful tools for synthesizing complex molecules.
• Traditional MCRs often require extensive functional group protection/deprotection steps, limiting efficiency and diversity.
• Enzymatic catalysis offers high chemoselectivity and mild reaction conditions, potentially streamlining MCR precursor preparation.

Purpose of the Study:

• To develop a chemoenzymatic strategy for preparing diverse precursors for Ugi condensation.
• To utilize enzymatic acylation for selective modification of carboxylic acid and amine building blocks.
• To expand the structural diversity achievable in Ugi products through selective enzymatic functionalization.

Main Methods:

• Selective enzymatic acylation of 3-hydroxybutyrate and 4-amino-1-butanol using porcine pancreatic lipase and various acyl donors.
• Preparation of alpha-(acylamino)amide Ugi products via a four-component condensation reaction.
• Characterization of the nine-member Ugi condensation library.

Main Results:

• Porcine pancreatic lipase selectively acylated the hydroxyl groups of both precursors.
• Enzymatically generated 3-acyl-butyric acid and 4-amino-1-acyl derivatives were successfully synthesized.
• Isolated yields for the alpha-(acylamino)amide Ugi products ranged from 72-95%.

Conclusions:

• Chemoenzymatic approaches enable selective precursor modification for MCRs.
• Enzymatic catalysis enhances the efficiency and structural diversity of Ugi condensation reactions.
• This strategy holds promise for broader applications in combinatorial chemistry and drug discovery.