Highly optimized β-mannosylation via p-methoxybenzyl assisted intramolecular aglycon delivery

被引：102

作者：

Ito, Y

Ohnishi, Y

Ogawa, T

Nakahara, Y

机构：

[1] RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan

[2] Japan Sci & Technol Corp, CREST, Wako, Saitama 3510198, Japan

[3] Tokai Univ, Dept Ind Chem, Hiratsuka, Kanagawa 2591292, Japan

来源：

SYNLETT | 1998年 / 10期

关键词：

beta-mannosylation; intramolecular aglycon delivery; thioglycoside; asparagine-linked oligosaccharide;

D O I：

10.1055/s-1998-1894

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Highly efficient and stereoselective beta-mannosylation was achieved by using mannosyl thioglycosides 5 and 19. Intramolecular aglycon delivery (IAD) from mixed acetal 12, 15 and 20, obtainable by oxidative coupling of aglycon onto mannosyl thio-glycosides which carry p-methoxybenzyl (PMB) group at C-2 position, was performed by the action of MeOSO2CF3 to afford beta-mannosides 13/16/21. It is to be noted that efficiency of IAD was substantially improved by changing the protecting group at the 4- and 6- positions from previously utilized benzylidene to cyclohexylidene (5) or TIPDS (19) group. As a result, it is now possible to perform the beta-manno glycosylation in a highly optimized manner to afford di- and trisaccharides with a backbone structure corresponding to asparagine-linked oligosaccharides in 75-85% yield as single stereoisomers.

引用

页码：1102 / +

页数：4

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