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Updated: May 17, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Synthesis of 5-halogenated 1,2,3-triazoles under stoichiometric Cu(I)-mediated azide-alkyne cycloaddition (CuAAC or
David Goyard1, Jean-Pierre Praly, Sébastien Vidal
1Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Laboratoire de Chimie Organique 2-Glycochimie, UMR 5246, CNRS, Université Claude Bernard Lyon 1, Villeurbanne, France.
Abstract:
Glucosylated heterocycles have been identified as potent inhibitors of glycogen phosphorylase (GP), a biomolecular target for the treatment of hyperglycemia and therefore type 2 diabetes. Several glucosylated triazoles have been evaluated as GP inhibitors and additional structures are being considered in the present study with the introduction of a substituent at the 5-position of the triazole ring. The 1,3-dipolar cycloaddition of azide and alkyne using stoichiometric amounts of Cu(I) halides favored the formation of the 5-halogenated 1,2,3-triazoles. The influence of the copper halide introduced (CuI, CuBr, or CuCl) provided different results and more specifically for the CuCl system which afforded a dimeric 5,5'-bistriazole in good yield (56%) as evidenced by crystallographic data.
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