182622-28-2

Upstream product

• 86196-36-3 benzyl α-D-galactopyranoside 
• 77-76-9 2,2-dimethoxy-propane 

Downstream Products

• 203172-18-3 benzyl 2,6-di-O-acetyl-3,4-O-isopropylidene-α-D-galactopyranoside 
• 346420-62-0 Benzyl 2,6-Di-O-benzoyl-3,4-O-isopropylidene-α-D-galactopyranoside 
• 203172-26-3 4-[(2S,3R,6S)-6-(tert-Butyl-diphenyl-silanyloxymethyl)-3-methoxy-tetrahydro-pyran-2-yl]-butan-1-ol 
• 203172-29-6 tert-Butyl-((2S,5R,6R)-5-methoxy-1,7-dioxa-spiro[5.5]undec-2-ylmethoxy)-diphenyl-silane 
• 203172-28-5 tert-Butyl-((2S,5R,6S)-5-methoxy-1,7-dioxa-spiro[5.5]undec-2-ylmethoxy)-diphenyl-silane 
• 203172-24-1 tert-Butyl-((2S,5R,6S)-5-methoxy-6-pent-4-enyl-tetrahydro-pyran-2-ylmethoxy)-diphenyl-silane 
• 203172-25-2 tert-Butyl-((2S,5R,6R)-5-methoxy-6-pent-4-enyl-tetrahydro-pyran-2-ylmethoxy)-diphenyl-silane 
• 203172-22-9 ((2S,5R,6S)-6-Benzyloxy-5-methoxy-tetrahydro-pyran-2-ylmethoxy)-tert-butyl-diphenyl-silane 
• 203172-21-8 (2S,3R,6S)-2-Benzyloxy-6-(tert-butyl-diphenyl-silanyloxymethyl)-tetrahydro-pyran-3-ol 
• 182622-30-6 benzyl 2,6-di-O-acetyl-3,4-O-thiocarbonyl-α-D-galactopyranoside 
• 203172-27-4 4-[(2R,3R,6S)-6-(tert-Butyl-diphenyl-silanyloxymethyl)-3-methoxy-tetrahydro-pyran-2-yl]-butan-1-ol 
• 182622-29-3 benzyl 2,6-di-O-acetyl-α-D-galactopyranoside 
• 182622-54-4 Toluene-4-sulfonic acid (2S,5R,6S)-5-methoxy-1,7-dioxa-spiro[5.5]undec-2-ylmethyl ester 
• 182622-31-7 Acetic acid (2S,3R,6S)-6-acetoxymethyl-2-benzyloxy-3,6-dihydro-2H-pyran-3-yl ester 

Relevant academic research and scientific papers

Synthesis of clustered xenotransplantation antagonists using palladium-catalyzed cross-coupling of prop-2-ynyl α-D-galactopyranoside

Hyperacute rejection of pig liver transplantation can be antagonized using high affinity anti α-galactoside epitopes (Galα1-3Galβ, Galili antigen). To this end, clusters containing the Galili antigen were synthesized using palladium cross-coupling reactions. Thus, benzyl 3-(O-α-D-galactopyranosyl)-β-D-galactopyranoside derivative 6 was prepared using perbenzylated thiophenyl β-D-galactopyranosyl donor 5 and benzyl 2,6-di-O-benzoyl-α-D-galactopyranosyl acceptor 3. Aglycone interchange from benzyl to prop-2-ynyl disaccharide 8 was successively achieved by hydrogenolysis, peracetylation, regioselective anomeric de-O-acetylation, trichloroacetimidate activation, and finally coupling to propargyl alcohol with triflic acid. The resulting prop-2-ynyl disaccharide 8 was transformed in high yields (>85%) into dimer 10, trimer 12, and tetramer 17 using oxidative homocoupling (10) and palladium-catalyzed aryl iodide cross-coupling (12,17), respectively. Ester protecting group removal under transesterification conditions afforded fully deprotected α-Gal clusters.

Syntheses of chiral dispiroacetals from carbohydrates

The syntheses of trioxadispiroacetals from carbohydrates are described. (5R,7S,13R)-13-Methoxy-1,6,8-trioxadispiro[4.1.5.3]pentadecane (23) and (5S,7S,13R)-13-methoxy-1,6,8-trioxadispiro[4.1.5.3]-pentadecane (24) were prepared starting from D-galactose. The construction of the lateral tetrahydrofuran and tetrahydropyran rings was realized by homologation at C1 and C6 by appropriate tethers possessing a terminal primary alcohol. The cyclization of these alcohols at C1 and C5, respectively, was performed with (diacetoxyiodo)benzene and iodine in order to generate the alkoxy radicals which undergo an intramolecular hydrogen abstraction reaction. The diastereoisomers (5R,7S,13S)-13-methoxy-1,6,8- trioxadispiro[4.1.5.3]pentadecane (37) and (5S,7S,13S)-13-methoxyl-1,6,8- trioxadispiro[4.1.5.3]pentadecane (38) were prepared starting from tri-O- acetyl-D-glucal using a suitable methodology in which homologation and intramolecular hydrogen abstraction were again the key steps. We believe that this protocol could be easily extended to other tricyclic dispiroacetal ring systems.

Synthesis of dispiroacetals from carbohydrates by intramolecular hydrogen abstractions

The synthesis of 1,6,8-trioxadispiro[4.1.5.3]pentadecanes 15 and 16 from D-galactopyranose is described. The key steps are two intramolecular hydrogen abstraction reactions promoted by alkoxy radicals.