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Updated: Jun 6, 2026

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
Solvent-free thermocyclization of the unactivated linear gramicidin S precursor and analogues
Lin-Kun An1, Run-Lin Li, Ying-Lin Zuo
1School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China. lssalk@mail.sysu.edu.cn
Abstract:
A convenient thermocyclization of the linear gramicidin S precursor and its analogues is demonstrated. With the preorganized β-sheet conformation, the unactivated linear precursors can cyclize into the corresponding head-to-tail cyclic products in high yield after being heated under solvent-free conditions.
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