51532-76-4

Upstream product

• 55628-56-3 1,2-di-O-acetyl-3,4,6-tri-O-benzyl-β-D-glucopyranoside 
• 4064-06-6 1,2:3,4-di-O-isopropylidene-α-D-galactopyranose 
• 121388-85-0 tri-O-benzyl-α-D-glucopyranose-(1,2-t-butylorthoacetate) 
• 108869-64-3 3,4,6-tri-O-benzyl-2-O-acetyl-α-D-glucosyl trichloroimidate 
• 55628-54-1 3,4,6-tri-O-benzyl-D-glucal 
• 127299-77-8 Phenyl 3,4,6-tri-O-benzyl-1-thio-β-D-glucopyranoside 
• 572-09-8 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide 
• 65827-55-6 1,2-di-O-acetyl-3,4,6-tri-O-benzyl-α-D-glucopyranoside 
• 189182-66-9 2-O-acetyl-3,4,6-tri-O-benzyl-D-glucopyranosyl trichloroacetimidate 

Downstream Products

• 40246-33-1 3,4,6-tri-O-benzyl-β-D-glucopyranoside-(1->6)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranoside 
• 79384-22-8 O-(3,4,6-tri-O-benzyl-2-deoxy-β-D-glucopyranosyl)-(1[*]6)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose 
• 121399-46-0 1,2:3,4-di-O-isopropylidene-6-O-(3,4,6-tri-O-benzyl-2-O-(methylthio)thiocarbonyl-β-D-glucopyranosyl)-α-D-galactopyranose 
• 213028-97-8 6-O-(3,4,6-tri-O-benzyl-2-O-trifluoromethanesulfonyl-β-D-glucopyranosyl)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose 
• 153947-47-8 6-O-(2-O-acetyl-3,4,6-tri-O-benzyl-β-D-mannopyranosyl)-1,2:3,4-di-O-isopropylidene-α-D-galactopyranose 
• 112330-11-7 (3,4,6-tri-O-benzyI-β-D-mannopyranosyl)-(1→6)-1,2,3,4-di-O-isoprpopylidene-α-D-galactopyranoside 
• 40246-34-2 (2R,4S,5R,6R)-4,5-Bis-benzyloxy-6-benzyloxymethyl-2-((3aR,5R,5aS,8aS,8bR)-2,2,7,7-tetramethyl-tetrahydro-bis[1,3]dioxolo[4,5-b;4',5'-d]pyran-5-ylmethoxy)-dihydro-pyran-3-one 

Relevant academic research and scientific papers

C2-(1 N/2 N-Methyl-tetrazole)methyl Ether (MeTetMe) as a Stereodirecting Group for 1,2-trans-β-O-Glycosylation

Development of stereoselective synthetic methods for O-glycosides is of paramount importance in the field of glycochemistry. Therefore, we report herein (1 N/2 N)-methylated tetrazole methyl (MeTetMe) ethers as a C2-directing group for the formation of 1,2-trans-β-O-glycosides. The synthesis of the tetrazole moiety was readily achieved by a 3+2 cycloaddition reaction on nitrile functionality. The tethered thioglycoside donors were found to deliver the β-O-glycosides when activated by PIFA-TfOH reagent system. The reactions were performed with six newly synthesized phenyl and ethyl thioglycosides to obtain the glycosylated adducts in moderate to high yields and excellent to exclusive β-selectivity. The glycosylation method was easily scalable up to grams without affecting the yield and stereoselectivity. The MeTetMe group was efficiently removed under Birch reduction conditions without affecting the benzyl ethers or isopropylidene acetal protection.

Cyanomethyl Ether as an Orthogonal Participating Group for Stereoselective Synthesis of 1,2-trans-β-O-Glycosides

Stereoselective formation of glycosidic linkages has been the prime focus for contemporary carbohydrate chemistry. Herein, we report cyanomethyl (CNMe) ether as an efficient and effective participating orthogonal protecting group for the stereoselective synthesis of 1,2-trans-β-O-glycosides. The participating group facilitated good to high β-selective glycosylation with a broad range of electron-rich and electron-deficient glycosyl acceptors. Detailed experimental and theoretical studies reveal the involvement of CNMe ether in the formation of a six-membered imine-type cyclic intermediate for the observed stereoselectivity. Rapid incorporation and selective removal of the CNMe ether group in the presence of benzyl ether and isopropylidene acetal protection have also been reported here. The nitrile group provided an opportunity for the glycodiversification through further derivatizations.

N-Pentenyl-Type Glycosides for Catalytic Glycosylation and Their Application in Single-Catalyst One-Pot Oligosaccharide Assemblies

We have developed a new type of n-pentenyl-type glycosides that can be activated by catalytic amounts of promoter, Hg(NTf2)2 or PPh3AuCl/AgNTf2, at room temperature. The mild activation conditions and outstanding stability of common protection/deprotection manipulations enable the enynyl donors to have broad applications in constructing various glycosidic bonds. Furthermore, under the Hg(NTf2)2-catalyzed conditions, the sequential activation of different types of donors was achieved, based on which a gentiotetrasaccharide was synthesized via the newly developed single-catalyst one-pot strategy.

Acid-Catalyzed O-Glycosylation with Stable Thioglycoside Donors

Two classes of thioglycoside, 4-(4-methoxyphenyl)-3-butenylthioglycosides (MBTGs) and 4-(4-methoxyphenyl)-4-pentenylthioglycosides (MPTGs), undergo acid-catalyzed O-glycosylations with a range of sugar and nonsugar alcohols at 25 °C. Electron density at t

Investigation of α-Thioglycoside Donors: Reactivity Studies toward Configuration-Controlled Orthogonal Activation in One-Pot Systems

The influence of anomeric configuration upon thioglycoside donors remains relatively unexplored. Utilizing methodology developed for the stereoselective and high-yielding synthesis of α-glycosyl thiols, a series of α-thioglycosides were synthesized, and their reactivity was compared to that of their β-counterparts. The highly selective activation observed for anomeric pairs containing a 2-O-acyl moiety and additional findings are reported. Application of a pair of superarmed thioglycosides to a one-pot oligosaccharide system is also described, in which selectivity is a result of configuration-based orthogonal activation.

A visible-light-promoted O-glycosylation with a thioglycoside donor

Visible-light irradiation of 4-p-methoxyphenyl-3-butenylthioglucoside donors in the presence of Umemoto's reagent and alcohol acceptors serves as a mild approach to O-glycosylation. Visible-light photocatalysts are not required for activation, and alkyl- and arylthioglycosides not bearing the p-methoxystyrene are inert to these conditions. Experimental and computational evidence for an intervening electron donor-acceptor complex, which is necessary for reactivity, is provided. Yields with primary, secondary, and tertiary alcohol acceptors range from moderate to high. Complete β-selectivity can be attained through neighboring-group participation. Visible-light irradiation of 4-p-methoxyphenyl-3-butenylthioglucoside donors in the presence of Umemoto's reagent serves as an exceptionally mild and orthogonal approach to O-glycosylation. Alkyl- and arylthioglycosides not containing the p-methoxystyrene moiety are inert under these conditions, and evidence suggests that an intervening electron donor-acceptor complex is necessary for reactivity.

Interrupted Pummerer Reaction in Latent-Active Glycosylation: Glycosyl Donors with a Recyclable and Regenerative Leaving Group

Latent O-glycosides, 2-(2-propylthiol)benzyl (PTB) glycosides, were converted into the corresponding active glycosyl donors, 2-(2-propylsulfinyl)benzyl (PSB) glycosides, by a simple and efficient oxidation. Treatment of the PSB donor and various acceptors with triflic anhydride provided the desired glycosides in good to excellent yields. The leaving group, which was activated by an interrupted Pummerer reaction, can be recycled (PSB-OH) and regenerated as the precursor (PTB-OH). A natural hepatoprotective glycoside, leonoside F, was efficiently synthesized in a convergent [3+1] manner with this newly developed method. The present total synthesis also led to a structural revision of this phenylethanoid glycoside.

[R4N] [AOT]: A surfactant ionic liquid as a mild glycosylation promoter

[RN4][AOT] is a versatile surfactant ionic liquid that can be used in combination with N-Iodosuccinimide to promote the room temperature glycosylation of thiophenyl glycoside donors. The conditions are mild, with no requirement for molecular si

[bmim][OTf] as co-solvent/promoter in room temperature reactivity-based one-pot glycosylation reactions

[bmim][OTf] can promote regio- and chemo-selective glycosylation reactions at room temperature. Furthermore, the applicability to ambient three-component reactivity-based one-pot glycosylation reactions is demonstrated for the synthesis of several trisacc

Stereospecific access to β-mannosides from glucose-derived 1,2-orthoesters as glycosyl donors

A new, stereospecific synthesis of β-mannosides from glucose-derived 1,2-orthoesters has been developed by a simple four step procedure, comprising β-specific glycosidation of the 1,2-orthoesters, 2′-O-deacetylation, 2′-O-triflation, and SN 2 type inversi