Kim Kwan Soo, Suk Dae-Hwan
Center for Bioactive Molecular Hybrids and Department of Chemistry, Yonsei University, Seoul, 120-749, Korea.
Top Curr Chem. 2011;301:109-40. doi: 10.1007/128_2010_107.
Here we review the equatorial β-directing effects of electron-withdrawing protecting groups at remote positions of mannopyranosyl donors, mannuronate donors, rhamnopyranosyl donors, and 2,6-dideoxyglucopyranosyl donors. We discuss the equatorial α-directing effect of an electron-withdrawing group at the N-5 position of sialyl donors. The proposed mechanism and origin of some of the equatorial β-directing effects are described. We also review the effects of potentially participating, electron-withdrawing protecting groups at remote positions of glycopyranosyl and glycofuranosyl donors on the glycosylation stereochemistries. Further, we present substantial evidence in favor of the remote participation by the electron-withdrawing protecting groups and also include reports that are opposed to remote participation.
在此，我们综述了在甘露吡喃糖基供体、甘露糖醛酸供体、鼠李吡喃糖基供体和2,6-二脱氧葡萄糖吡喃糖基供体的远程位置上吸电子保护基团的赤道β-导向效应。我们讨论了唾液酸基供体N-5位上吸电子基团的赤道α-导向效应。描述了一些赤道β-导向效应的提出机制和起源。我们还综述了在吡喃糖基和呋喃糖基供体的远程位置上潜在参与的吸电子保护基团对糖基化立体化学的影响。此外，我们提供了大量支持吸电子保护基团远程参与的证据，同时也纳入了反对远程参与的报道。
