Synthetic Access Toward Cycloastragenol Glycosides.

  title={Synthetic Access Toward Cycloastragenol Glycosides.},
  author={Ting Liu and Jinxi Liao and Yang Hu and Yuan-Hong Tu and Jian-Song Sun},
  journal={The Journal of organic chemistry},
  volume={82 8},
The first efficient synthetic approach toward four types of the cycloartane glycosides, the cycloastragenol 25-O; 3-O; 3,6-O-bis; and 3,25-O-bisglycoside, have been established, which featured the PPY-mediated, concentration-controlled acetylation and Au(I)-catalyzed Yu glycosylation. Through the synthetic investigation, the reactivity sequence of the four OHs in cycloastragenol was fixed for the first time and a detour strategy for the highly efficient removal of bulky pivaloyl protecting… Expand
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