Linear Hexasaccharides

2 Branched Homohexasaccharides. - A one-pot synthesis of a 3- and 6-0-dilferentially protected glucoside gave access to a highly efficient synthesis of the P-(l- 3) linked glucotetraose with p-(l- 6) branches on units 1 and 3.  

A European and a Japanese group have completed the preparation of sialylgalactosylgloboside 10. The latter workers also made the isomer 

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Scheme 2.8 Solid-phase synthesis of a linear hexasaccharide.

The linear hexasaccharide 0-Q-L-Rhap-( l->2)-Q-a-L-Rhap-( l->3)-O-a-L-Rhap- ( 1-3 ) -0- -D-GlcpNAc- ( l- 2 ) -O-a-L-Rhafi- (l- 2 ) -Q-a-L-RhapPr, the hapten of Shigella flexneri variant Y polysaccharide, has been characterised by 2D NMR and synthesised. 

Linear Hexasaccharides.— / Nitrophenyl a-maltohexaoside was made by enzymic transglycosylation (probably of enzyme bound maltopentaose) between maltohexaose and p-nitrophenyl a-Z)-glucopyranoside in water containing DMSO (40%) or butan-l-ol or propan-2-ol (20%). A methyl glycoside of the hexaose based on 4-deoxy-4-fonnylmethyl-o-2)-rhamnopyranose has been made by the thioglycoside procedure. ... 

Fig. 6 Synthesis of cyclic mannohexaose from linear hexasaccharide. ...

Yet another early example differing in glyeosidie linkage is the synthesis of (1 3)-p-linked cyeloglucohexaose 15, prepared from linear hexasaccharide 14 (Fig. 10). Step-wise addition of individual sugar moieties to a growing linear oligomer afforded the desired hexasaccharide... 

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