Beilstein J. Org. Chem.2017,13, 2094–2114, doi:10.3762/bjoc.13.207
, which has been covered in other reviews [23][42], has been applied to successful synthesis of a range of complex oligosaccharides including humanmilkoligosaccharides [45], an embryonic stem cell surface carbohydrate marker Lc4 [46], Globo-H hexasaccharide [47], and heparin-like oligosaccharides [48
PDF
Graphical Abstract
Scheme 1:
a) Traditional glycosylation typically employs the premixed approach with both the donor and the ac...
Beilstein J. Org. Chem.2010,6, No. 18, doi:10.3762/bjoc.6.18
derivatives.
Keywords: block synthesis; humanmilkoligosaccharides; sialyllacto-N-neotetraose epimer; sialyllacto-N-tetraose; trisaccharide thioglycoside donors; Introduction
From an inspection of contemporary syntheses of biologically and medicinally relevant oligosaccharides, it is evident that the
, sialyllacto-N-tetraose (1) and an epimer of sialyllacto-N-neotetraose (2) (Figure 1) were selected as target molecules. Both these pentasaccharides, Neu5Acα2-3Galβ1-3GlcNAcβ1-3Galβ1-4Glc (1) and Neu5Acα2-6Galβ1-4GlcNAcβ1-4Galβ1-4Glc (2), are dominant constituents of complex humanmilkoligosaccharides (Figure
humanmilkoligosaccharides are considered as soluble receptor analogues of epithelial cell surfaces [6].
Results and Discussion
Previously, we reported the chemoenzymatic synthesis of the 3-sialylated lactosamine derivative 3 obtained by the enzymatic β-galactosylation of the 2-azidothioglucoside with