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Updated: Jun 25, 2026

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
The conformation of a tetratritylated alpha-cyclodextrin with unusual proton NMR
Sandra Ward1, Ping Zhang, Chang-Chun Ling
1Alberta Ingenuity Center for Carbohydrate Science, Department of Chemistry, University of Calgary, Calgary, Alberta, Canada.
Abstract:
Tetratritylation of alpha-cyclodextrin (CD) and subsequent peracetylation of the partially tritylated mixture allowed the preparation and isolation of the symmetrical 6(A),6(B),6(D),6(E)-tetratritylated alpha-CD in pure form. The (1)H NMR spectra of the compound showed abnormal behaviour with the anomeric proton of one of the glycopyranosyl systems resonating below 3.0 ppm, which is exceptionally unusual. To understand this anomaly in the (1)H NMR data, we performed a complete NMR analysis and using molecular modelling as a tool, we were able to obtain a conformation that can explain the observed NMR phenomenon.
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