Succinoyl Diester

The base lability of succinoyl diester hnker severely limits the selection of protecting groups available for an oligosaccharide synthesis, so a more versatile tether was required. Diether bonds of benzylphenol or dibenzyl of 1,4-di(hydroxymethyl)-benzene satisfy this requirement because they are stable to both bases and to acids. A sufficient acid stability is important since the formation of a glycosidic bond is an acid-catalyzed reaction, not surprisingly, as it is an acetal functionality. For instance, DOX,34 the dibenzyl hnker a,a -DiOxyXylyl diether, -0CH2C6H4CH20-, is not limited by restriction of the succinoyl hnker (1) when bound via a hydroxyl or as an... 

To synthesize an oligosaccharide, MPEG is bound to a hydroxyl of the first monosaccharide through the succinoyl diester linker (Scheme 1). Next, another hydroxyl of this monosaccharide is deprotected, glycosylated, temporary protection on the second monosaccharide is removed and the above process is repeated until the required oligosaccharide is synthesized. Although incomplete glycosylation can... 

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