Regioselective and 1,2-cis-α-Stereoselective Glycosylation Utilizing Glycosyl-Acceptor-Derived Boronic Ester Catalyst
Akira Nakagawa1, Masamichi Tanaka1, Shun Hanamura1
1Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan).
Abstract:
Regioselective and 1,2-cis-α-stereoselective glycosylations using 1α,2α-anhydro glycosyl donors and diol glycosyl acceptors in the presence of a glycosyl-acceptor-derived boronic ester catalyst. The reactions proceed smoothly to give the corresponding 1,2-cis-α-glycosides with high stereo- and regioselectivities in high yields without any further additives under mild reaction conditions. In addition, the present glycosylation method was successfully applied to the synthesis of an isoflavone glycoside.
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