title: Rationally designed syntheses of high-mannose and complex type undecasaccharides.
abstract: Synthetic routes are described to a high-mannose type triantenary undecasaccharide 1 and a completely protected form 39 of the complex type biantenary undecasaccharide 2 carrying alpha-(2-->3)-linked sialic acid residues. Starting from a previously reported trisaccharide 4, the core pentasaccharides 15 and 37 were synthesized through regio- and/or stereo-selective mannosylation with a suitably protected mannosyl donor. Chain elongation of 15 by stepwise addition of a mannose residue afforded an undecasaccharide 20 that was eventually deprotected to give 1. On the other hand, coupling of 38 and a trisaccharide glycosyl donor 36 afforded 39.
authors.affiliation: Institute of Physical and Chemical Research (RIKEN), Saitama, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Nakahara
authors.forename: S
authors.initials: S
authors.lastname: Shibayama
authors.forename: Y
authors.initials: Y
authors.lastname: Nakahara
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
mesh_terms: D000117:Acetylglucosamine / Q000031:analogs & derivatives; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000032:analysis*; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D011134:Polysaccharides / Q000138:chemical synthesis / Q000737:chemistry; D014312:Trisaccharides / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D009844:Oligosaccharides; D011134:Polysaccharides; D014312:Trisaccharides; D008358:Mannose; D000117:Acetylglucosamine