Synthesis of ribo-hexopyranoside- and altrose-based azacrown ethers and their application in an asymmetric Michael addition
作者:Zsolt Rapi、Péter Bakó、György Keglevich、Áron Szöllősy、László Drahos、László Hegedűs
DOI:10.1016/j.carres.2012.10.020
日期:2013.1
The synthesis of four new ribo-hexopyranoside-based chiral lariat ethers of monoaza-15-crown-5 type and two altropyranoside-based crown ethers were elaborated. Our syntheses utilized the regioselective ring opening of the oxiran moiety of the 2,3-anhydro sugars by nucleophilic reagents to afford the key intermediates. The reaction of methyl-2,3-anhydro-4,6-O-benzylidene-α-D-mannopyranoside with ethanolamine
合成了四种新的单氮杂15冠5型基于核糖-己吡喃糖苷的手性套索状醚和两种基于阿拉托吡喃糖苷的冠状醚。我们的合成通过亲核试剂利用了2,3-脱水糖的环氧乙烷部分的区域选择性开环,以提供关键的中间体。甲基-2,3-脱水-4,6-O-亚苄基-α-D-甘露吡喃糖苷与乙醇胺的反应特别令人感兴趣,以提供3-取代的萘并吡喃糖苷。当在相转移催化条件下用作乙酰氨基丙二酸二乙酯向反式-β-硝基苯乙烯的迈克尔加成反应中的催化剂时,一种具有4-甲氧基苯基取代基的基于核糖-六吡喃糖苷的套索状醚诱导对映选择性为80%。