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Updated: Jun 12, 2025

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
β-Silyl alkynoates: Versatile reagents for biocompatible and selective amide bond formation
Khokan Choudhuri1,2, Zhenguo Zhang1,2, Teck-Peng Loh1,2
1College of Advanced Interdisciplinary Science and Technology, Henan University of Technology, Zhengzhou 450001, China.
Abstract:
The study introduces a previously unidentified method for amide bond formation that addresses several limitations of conventional approaches. It uses the β-silyl alkynoate molecule, where the alkynyl group activates the ester for efficient amide formation, while the bulky TIPS (triisopropylsilane) group prevents unwanted 1,4-addition reactions. This approach exhibits high chemoselectivity for amines, making the method compatible with a wide range of substrates, including secondary amines, and targets the specific ε-amino group of lysine among the native amino ester's derivatives. It maintains stereochemistry during amide bond formation and TIPS group removal, allowing a versatile platform for postsynthesis modifications such as click reactions and peptide-drug conjugations. These advancements hold substantial promise for pharmaceutical development and peptide engineering, opening avenues for research applications.
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