β-Selective Mannosylation with a 4,6-Silyiene-Tethered Thiomannosyl Donor
β-Selective Mannosylation with a 4,6-Silyiene-Tethered Thiomannosyl Donor
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DOI：
10.1021/ol403722f
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发表时间：
2014-02-21
期刊：
影响因子：
5.2
通讯作者：
Bols, Mikael
中科院分区：
文献类型：
--
作者：
Heuckendorff, Mads;Bendix, Jesper;Bols, Mikael
已发现使用新的构象受限供体苯基2，3-二-O-苄基-4，6-O-（二叔丁基亚甲硅烷基）-1-硫代-α-D-吡喃甘露糖苷（6）的甘露糖基化在各种活化条件下具有β-选择性。最简单的活化条件是NIS/TfOH，在这种情况下，提出β-甘露糖苷是由B-2，B-5构象的氧碳正离子25的β-选择性糖基化形成的。
Mannosylations using the new conformationally restricted donor phenyl 2,3-di-O-benzyl-4,6-O-(di-tert-butylsilylene)-1-thio-alpha-D-mannopyranoside (6) have been found to be beta-selective with a variety of activation conditions. The simplest activation conditions were NIS/TfOH, in which case it is proposed that the beta-mannoside is formed from beta-selective glycosylation of the oxocarbenium ion 25 in a B-2,B-5 conformation.