An Efficient Approach towards the Convergent Synthesis of “Fully-Carbohydrate” Mannodendrimers
作者:Leon V. Backinowsky、Polina I. Abronina、Alexander S. Shashkov、Alexey A. Grachev、Nikolay K. Kochetkov、Sergey A. Nepogodiev、J. Fraser Stoddart
DOI:10.1002/1521-3765(20021004)8:19<4412::aid-chem4412>3.0.co;2-f
日期:2002.10.4
one equivalent of the donor 1 gave rise to the isomeric tetrasaccharide derivatives, Manalpha1-->3(Manalpha1-->6)Manalpha1-->6ManalphaOMe and Manalpha1-->3(Manalpha1-->6)Manalpha1-->3ManalphaOMe, respectively. The latter derivative was further mannosylated at the remaining 6-O-trityl acceptor site to give the protected pentasaccharide Manalpha1-->3(Manalpha1-->6)Manalpha1-->3(Manalpha1-->6)ManalphaOMe
糖三苯甲基醚与糖1,2-O-(1-氰基)亚乙基衍生物的糖基化作用(三苯甲基-氰基亚乙基缩合)已用于合成结合Manalpha1-> 3(Manalpha1- -> 6)人的结构图案。用于组装这些寡糖的收敛合成策略是基于使用已经带有该结构基序的糖基受体和/或糖基供体。前者以ManalphaOMe,Manalpha1-> 3ManalphaOMe和Manalpha1-> 3(Manalpha1-> 6)ManalphaX的单和二三苯醚表示,其中X = OMe或SEt。关键的糖基供体是通过正交Helferich糖基化制备的过乙酰化的1,2-O-(1-氰基)亚乙基-3,6-二-O-(α-D-甘露吡喃糖基)-β-D-甘露吡喃糖(1)。在已知的1中,2-O-(1-氰基)亚乙基-β-D-甘露吡喃糖与四-O-乙酰基-α-D-甘露吡喃糖基溴化物,然后进行O-乙酰化。甲基6-O-三苯甲基-α-D-甘露糖吡喃糖苷和甲基3