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Published on: August 22, 2018
A Ring Expansion Approach To N-oxy-2,5-diketopiperazines
Amy C Jackson1, James T Olsen1, Sasha Sundstrom1
1Department of Chemistry and Biochemistry, Baylor University, Waco, TX, 76706.
A new ring expansion method transforms tetramic acids into N-oxy-2,5-diketopiperazines (DKPs). This approach enables efficient, late-stage synthesis of the hydroxamic acid group, useful for creating N-oxy-2,5-DKP natural products.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
Background:
- Tetramic acids are versatile synthetic intermediates.
- N-oxy-2,5-diketopiperazines (DKPs) are a class of natural products with significant biological activities.
- Accessing N-oxy-2,5-DKP natural products often requires complex synthetic strategies.
Purpose of the Study:
- To develop a facile and general method for the synthesis of N-oxy-2,5-diketopiperazines.
- To enable late-stage functionalization for the construction of the hydroxamic acid moiety.
Main Methods:
- Ring expansion of tetramic acids (pyrrolidine-2,4-diones).
- Utilizing specific reaction conditions to promote the transformation to N-oxy-2,5-diketopiperazines.
Main Results:
- Successful ring expansion of tetramic acids to N-oxy-2,5-diketopiperazines.
- Demonstration of facile and late-stage construction of the hydroxamic acid moiety.
- Establishment of a general method applicable to N-oxy-2,5-DKP natural product synthesis.
Conclusions:
- The described ring expansion provides an efficient route to N-oxy-2,5-diketopiperazines.
- This method simplifies the synthesis of complex natural products containing the N-oxy-2,5-DKP core.
- The strategy is valuable for medicinal chemistry and drug discovery efforts.
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