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Updated: Nov 3, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Efficient synthesis of cyclic amidine-based fluorophores via 6π-electrocyclic ring closure
Guofeng Li1, Man Zhao1, Junqiu Xie2
1Guangdong Key Laboratory of Chiral Molecular and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University Guangzhou 510006 China limin65@mail.sysu.edu.cn hongliang@sysu.edu.cn.
Abstract:
Novel 10π-electron cyclic amidines with excellent fluorescence properties were synthesized by a general and efficient 6π-electrocyclic ring closure of ketenimine and imine starting from N-sulfonyl triazoles and arylamines. The photophysical properties of cyclic amidine fluorophores have been studied in detail and have shown good properties of a large Stokes shift, pH insensitivity, low cytotoxicity and higher photostability, which have great potential for biological imaging. Furthermore, this novel fluorophore was successfully applied to the localization of the NK-1 receptor in living systems.
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