158852-06-3

Upstream product

• 627466-84-6 2,3,4,6-tetra-O-benzoyl-D-galactose 
• 59-23-4 D-Galactose 
• 98-88-4 benzoyl chloride 

Downstream Products

• 1449241-38-6 C₇₅H₇₄O₂₄ 
• 1309666-32-7 methyl 3-O-(2,3,4,6-tetra-O-benzoyl-β-D-galactopyranosyl)-2,3,4-tri-O-benzyl-α-D-glucopyranoside 
• 1309666-34-9 methyl 2-O-(2,3,4,6-tetra-O-benzoyl-β-D-galactopyranosyl)-2,3,4-tri-O-benzyl-α-D-glucopyranoside 

Relevant academic research and scientific papers

A Highly Efficient Glycosidation of Glycosyl Chlorides by Using Cooperative Silver(I) Oxide–Triflic Acid Catalysis

Following our discovery that silver(I) oxide-promoted glycosylation with glycosyl bromides can be greatly accelerated in the presence of catalytic TMSOTf or TfOH, we report herein a new discovery that glycosyl chlorides are even more effective glycosyl do

Synthesis of Glycosyl Chlorides and Bromides by Chelation Assisted Activation of Picolinic Esters under Mild Neutral Conditions

A general method has been developed for the formation of glycosyl chlorides and bromides from picolinic esters under mild and neutral conditions. Benchtop stable picolinic esters are activated by a copper(II) halide species to afford the corresponding products in high yields with a traceless leaving group. Rare β glycosyl chlorides are accessible via this route through neighboring group participation. Additionally, glycosyl chlorides with labile protecting groups previously not easily accessible can be prepared.

Synthesis of α-O- and α-S-glycosphingolipids related to sphingomonous cell wall antigens using anomerisation

Analogues of glycolipids from Spingomonadacaece with O- and S- and SO 2-linkages have been prepared using chelation induced anomerisation promoted by TiCl4. Included are examples of the anomerisation of intermediates with O- and S-glycosidic linkages as well as isomerisation of β-thioglycuronic acids (β-glycosyl thiols). The β-O-glucuronide and β-O-galacturonide precursors were efficiently prepared using benzoylated trichloroacetimidates. β-Glycosyl thiols were precursors to β-S-derivatives. Triazole containing mimics of the natural glycolipids were prepared using CuI promoted azide-alkyne cycloaddition reactions in THF. The glycolipid antigens are being evaluated currently for their effects on iNKT cells.

Indium(III) triflate-mediated one-step preparation of glycosyl halides from free sugars

In(OTf)3 has been found to be an efficient catalyst for the direct conversion of reducing sugars to their respective acylated glycosyl halides in good yields under mild conditions. The glycosyl halides so obtained can be converted to alkyl glyc

SnCl4- and TiCl4-catalyzed anomerization of acylated O - And S -glycosides: Analysis of factors that lead to higher α: β d reaction rates

The quantification of factors that influence both rates and stereoselectivity of anomerization reactions catalyzed by SnCl4 and TiCl4 and how this has informed the synthesis of α-O- and α-S-glycolipids is discussed. The SnCl4-catalyzed anomerization reactions of β-S- and β-O-glycosides of 18 substrates followed first order equilibrium kinetics and kf + kr values were obtained, where kf is the rate constant for the forward reaction (β → α) and kr is the rate constant for the reverse reaction (α → β). Comparison of the kf + k r values showed that reactions of glucuronic acid or galacturonic acid derivatives were ～10 to 3000 times faster than those of related glucoside and galactopyranoside counterparts and α:β ratios were generally also higher. Stereoelectronic effects contributed from galacto-configured compounds were up to 2-fold faster than those of corresponding glucosides. The introduction of groups, including protecting groups, which are increasingly electron releasing generally led to rate enhancements. The anomerization of S-glycosides was consistently faster than that of corresponding O-glycosides. Reactions were generally faster for reactions with TiCl4 than those with SnCl4. Anomeric ratios depended on the Lewis acid, the number equivalents of the Lewis acid, temperature, and substrate. Very high ratios of α-products for both O- and S-glucuronides were observed for reactions promoted by TiCl4; for these substrates TiCl4 was superior to SnCl4. Anomeric ratios from anomerization of S-glucosides were higher with SnCl4 than with TiCl4. The dependence of equilibrium ratio on Lewis acid and the number of equivalents of Lewis acid indicated that the equilibrium ratio is determined by a complex of the saccharide residue bound to the Lewis acid and not the free glycoside. The high α:β ratios observed for anomerization of both O- and S-glycuronic acids can be explained by coordination of the C-1 heteroatom and C-6 carbonyl group of the product to the Lewis acid, which would enhance the anomeric effect by increasing the electron-withdrawing ability of the anomeric substituent and lead to an increase in the proportion of the α-anomer. Such an observation would argue against the existence of a reverse anomeric effect. Support for a chelation-induced endocyclic cleavage mechanism for the anomerization is provided by the trapping of a key intermediate. The data herein will help predict the tendency of β-glycosides to undergo anomerization; this includes cases where 1,2-trans glycosides are initial products of glycosidation reactions catalyzed by TiCl4 or SnCl4.

A mild and general method for preparation of α-glycosyl chlorides

A mild and efficient chlorination method for production of glycosyl chlorides is first described which employs inexpensive trichlorotriazine (TCT) and DMF as a chlorination reagent and is compatible with typical acid-labile hydroxyl protecting functions. The scope and limitations, reaction mechanism and its application in the sequential glycosylations are discussed.