Perfectly Regioselective and Sequential Protection of Glucopyranosides

Abstract A perfectly regioselective and sequential method for the preparation of orthogonally protected glucopyranosides has been developed. An acyl group was introduced at C(4)‐OH by organocatalysis with >99 % regioselectivity. TBDPS, Boc, and BOM groups were sequentially introduced into the 4‐ O ‐acyl‐glucopyranoside at C(6)‐OH, C(2)‐OH, and C(3)‐OH, respectively, with ca. 100 % regioselectivity in each step.