6-Nitro-2-benzothiazolyl α-Mannoside: A Highly Efficient Mannosyl Donor in Constructing β-Man(1→4)GlcN Linkage and Its Application to the Synthesis of the Pentasaccharide Core of<i>N</i>-Glycans
作者:Hiroki Mandai、Teruaki Mukaiyama
DOI:10.1246/bcsj.79.479
日期:2006.3
An efficient and concise synthesis of the β-Man(1→4)GlcN linkage that exists in N-linked glycans has been established. Direct β-mannosylations of the 4-OH group of glucosamine derivatives by using ...
The intact peptide sequence (18) as well as its glycoform carrying an N-linked core pentasaccharide (I) of CD52 antigen were prepared by means of solid-phase synthesis employing Fmoc-amino acids and benzyl-protected oligo saccharide-asparagine conjugate (3) as building blocks. It was concluded that the pentasaccharide structure had little influence on further peptide elongation in solid-phase synthesis and the benzylated pentasaccharide moiety was sufficiently stable to the 95% TFA acidic conditions used to release glycopeptide from the supporting resin. The paper also describes an efficient route leading to asparagine-core pentasaccharide conjugate (3) which was prepared in seven steps for an overall yield of 23% from monosaccharide units 5, 6, 7 and 8. (C) 1997 Elsevier Science Ltd.