Chemical synthesis of 6(GlcNAc)- and 6(Gal)-O-sulfated SiaLeX tetrasaccharides in spacer-armed form

摘要

Practical synthesis of tetrasaccharide sulfates, 6(GlcNAc)-O-Su-SiaLeX-OCH₂CH₂CH₂NH₂ and 6(Gal)-O-Su-SiaLeX-OCH₂CH₂CH₂NH₂ (SuSO₃H), selectin ligands, and leu- kocyte trafficking agents is presented. Both sulfates were synthesized starting from the same precursor, protected SiaLex, by the conventional procedures of carbohydrate chemistry. The sulfated SiaLex derivative was modified at the spacer group to give 6(Gal)-O-Su-SiaLex- OCH₂CH₂CH₂NH-COCH₂CH₂C≡CH, convenient for “click chemistry” mode conjugation with an azido carrier, particularly, for the synthesis of an immunogen.