Blood-group li-active oligosaccharides. Synthesis of a tetrasaccharide, a β-(1 → 3) dimer of N-acetyl-lactosamine
作者:Alain Veyrières
DOI:10.1039/p19810001626
日期:——
afforded the 3′,4′-diol (5) derived from N-acetyl-lactosamine. This compound was selectively glycosylated at the 3′-position by the oxazoline (7) derived from lactosamine to give the protected tetrasaccharide (8) in 52% yield. Removal of the protecting groups gave the free tetrasaccharide β-D-Galp-(1 → 4)-β-D-GlcpNAc-(1 → 3)-β-D-Galp-(1 → 4)-D-GlcpNAc (9), a β-(1 → 3) dimer of N-acetyl-lactosamine. This structure
的苄基-2-乙酰氨基-3,6-二-缩合ø -苄基-2-脱氧- α- d吡喃葡萄糖苷(2)与2,3,4,6-四- ö乙酰基α- d -galactopyranosyl溴化物然后,通过脱-O-乙酰化,丙酮化,O-苄基化和酸性水解,得到了衍生自N-乙酰基-乳糖胺的3',4'-二醇(5)。该化合物被衍生自乳糖胺的恶唑啉(7)在3'-位选择性地糖基化,以52%的产率得到被保护的四糖(8)。除去保护基团得到游离的四糖β- D- Galp-(1→4)-β- D- GlcpNAc-(1→3)-β- D- Galp-(1→4)-D-GlcpNAc(9),是N-乙酰基乳糖胺的β-(1→3)二聚体。在从红细胞膜分离的各种糖脂中发现了这种结构,并且可以被几种抗安蒂斯菌识别。