Transactions of Tianjin University

, Volume 25, Issue 2, pp 185–194 | Cite as

Facile Synthesis of [1,2,4]Triazolo[4,3-a]pyrazin-3-amines via Oxidative Cyclization of 1-(Pyrazin-2-yl)guanidine Derivatives

  • Wei Li
  • Jieqiong Kang
  • Xueqin Zhou
  • Dongzhi Liu
  • Haiya Sun
  • Fang Xu
  • Tianyang WangEmail author
Research Article


In this study, we applied a novel, mild, and convenient synthetic method involving the oxidative cyclization of 1-(pyrazin-2-yl)guanidine derivatives to produce [1,2,4]triazolo[4,3-a]pyrazin-3-amines. We optimized the reaction procedure to easily obtain 5-chloro-[1,2,4]triazolo[4,3-a]pyrazin-3-amine. Various types of halogenated pyrazines can successfully undergo this process. We synthesized a series of 1-(pyrazin-2-yl)guanidines and [1,2,4]triazolo[4,3-a]pyrazin-3-amines, and then elucidated their structures based on their 1H-NMR, 13C-NMR, ESI-HRMS, and nuclear Overhauser effect spectra.


Triazolopyrazines [1,2,4]Triazolo[4,3-a]pyrazin-3-amines 1-(Pyrazin-2-yl)guanidines Cyclization Synthesis 



This study was supported by the National Nature Science Foundation of China (Nos. 21576195 and 21776207).

Supplementary material

12209_2018_158_MOESM1_ESM.doc (868 kb)
Supplementary material 1 (DOC 868 kb)


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Copyright information

© Tianjin University and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Wei Li
    • 1
    • 2
    • 3
  • Jieqiong Kang
    • 1
    • 2
  • Xueqin Zhou
    • 1
    • 2
    • 3
  • Dongzhi Liu
    • 1
    • 2
    • 3
  • Haiya Sun
    • 1
    • 2
  • Fang Xu
    • 1
    • 2
  • Tianyang Wang
    • 1
    • 2
    • 4
    Email author
  1. 1.School of Chemical Engineering and TechnologyTianjin UniversityTianjinChina
  2. 2.Collaborative Innovation Center of Chemical Science and EngineeringTianjinChina
  3. 3.Tianjin Engineering Research Center of Functional Fine ChemicalsTianjinChina
  4. 4.Tianjin Key Laboratory of Molecular Optoelectronic Science, School of ScienceTianjin UniversityTianjinChina

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