163121-75-3

Upstream product

• 81704-02-1 1,3,4,6-tetra-O-acetyl-2-deoxy-2-phthalimido-β-D-galactopyranoside 
• 150-76-5 4-methoxy-phenol 
• 131234-07-6 1,3,4,6-tetra-O-acetyl-2-deoxy-2-phthalimido-α,β-D-galactopyranose 

Downstream Products

• 179072-54-9 phenyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-1-thio-β-D-galactopyranoside 

Relevant academic research and scientific papers

A Highly α-Stereoselective Sialylation Method Using 4-O-4-Nitropicoloyl Thiosialoside Donor

An efficient α-sialylation methodology for various primary, secondary, and tertiary alcohol acceptors has been developed. The sialic acid ethyl thioglycoside 1b, bearing a 4-nitropicoloyl moiety as the stereodirecting group at the C4 position, was utilized as the glycosyl donor, and the sialylation reaction was activated with N-iodosuccinimide and catalytic triflic acid in a 1:1 mixture of dichloromethane/acetonitrile as solvent. The method was successfully applied to the stereocontrolled synthesis of protected trisaccharide 11 found in the repeating unit of serotype Ia Group B Streptococcus capsular polysaccharide.

Conversion of p-methoxyphenyl glycosides into the corresponding glycosyl chlorides and bromides, and into thiophenyl glycosides

p-Methoxyphenyl (pMP) β-D-glycopyranosides (Glc, Gal, GlcNPhth, GalNPhth, GlcNTroc, Galβ4Glc, Galα4Gal) were prepared from the corresponding 1-O-acetyl sugars in 79-90% yield, using boron trifluoride etherate as promoter. Treatment of the pMP glycosides with acyl chlorides or bromides in the presence of various Lewis acids gave the corresponding glycosyl chlorides and bromides in 81-98% yield. Treatment of the acyl-protected pMP glycosides with thiophenol and boron trifluoride etherate gave the corresponding thioglycosides in 80-100% yield and high (> 20:1) β/α selectivity. The stability of pMP glycosides was investigated against a series of reagents.

Studies related to synthesis of glycophosphatidylinositol membrane-bound protein anchors. 6. Convergent assembly of subunits

Glycophosphatidylinositol anchors of membrane-bound proteins are thought to comprise a common pentasaccharide core containing mannan, glucosamine, and inositol residues. A synthetic route to this core is described. In addition, the complete heptasaccharide moiety of the rat brain Thy-1 membrane anchor, the first mammalian membrane anchor to be characterized, has been synthesized. In the case of the Thy-1 anchor, the synthetic plan is based on three building blocks comprising glucosamine-inositol, galactosamine-mannose, and trimannan residues. Although glycosyl donors other than n-pentenyl glycosides (NPGs) have been used in preparing each of these building blocks, the final assembly of the heptasaccharide utilizes NPGs as the only glycosyl donors. The mildness of the conditions for these coupling reactions has allowed us to make provisions for subsequent installation of the three phosphodiester units.