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Updated: Nov 6, 2025

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Chemo- and regioselective ring-opening of donor-acceptor oxiranes with N-heteroaromatics
Ji-Wei Sang1, Ming-Sheng Xie1, Man-Man Wang1
1NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China. xiemingsheng@htu.edu.cn ghm@htu.edu.cn.
Abstract:
The first ring-opening of D-A oxiranes with N-heteroaromatics in a chemoselective C-C bond cleavage manner was achieved. In the presence of 5 mol% of Y(OTf)3 as the catalyst, diverse N-heteroaromatics, including benzotriazoles, purines, substituted benzimidazole, imidazole and pyrazole, reacted well with various D-A oxiranes, providing acyclic nucleoside analogues containing a N-glycosidic bond in up to 97% yield and up to >95 : 5 regioselectivity. Through simple transformation, the Ganciclovir analogue could also be obtained.
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