title: An efficient convergent synthesis of GP1c ganglioside epitope.
abstract: In this report, we describe an efficient convergent synthesis of the GP1c glycolipid epitope, which is one of the most complex c-series gangliosides. The alpha(2,3) and alpha(2,8) sialylations were accomplished by use of 5N,4O-carbonyl and 7,8-O-isopropyliden as well as 5N,4O-carbonyl- and 7,8-di-O-chloroacetyl-protected sialyl donors in good yields with excellent alpha-selectivity, respectively. The two sialyl donors enable synthesis of the di- and trisialylgalactosides by simple glycosylation and deprotection. We synthesized the protected GP1c glycolipid epitope, which is a compact, rigid, branched structure, via direct coupling of tetarasaccharide and pentasaccharide units.
authors.affiliation: Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology 2-12-1-S1-35, Oookayama, Meguro, Tokyo 152-8552, Japan. thiroshi@apc.titech.ac.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nishiura
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D002236:Carbohydrate Conformation; D002626:Chemistry, Pharmaceutical / Q000379:methods; D000939:Epitopes / Q000737:chemistry*; D005697:Galactosides / Q000737:chemistry; D005732:Gangliosides / Q000138:chemical synthesis* / Q000737:chemistry*; D006017:Glycolipids / Q000737:chemistry*; D006031:Glycosylation; D008956:Models, Chemical; D009844:Oligosaccharides / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D012794:Sialic Acids / Q000737:chemistry
chemical_list: D000939:Epitopes; D005697:Galactosides; D005732:Gangliosides; D006017:Glycolipids; D009844:Oligosaccharides; D011134:Polysaccharides; D012794:Sialic Acids; C048178:pentasialoganglioside GP1c