153808-91-4Relevant academic research and scientific papers
Homogeneous azidophenylselenylation of glycals using TMSN 3-Ph2Se2-PhI(OAc)2
Mironov, Yuri V.,Sherman, Andrei A.,Nifantiev, Nikolay E.
, p. 9107 - 9110 (2007/10/03)
The use of TMSN3 instead of NaN3 allows the reaction to be performed under homogeneous conditions, shortens the reaction time, and provides reliable scale-up. An improved preparative method for homogeneous azidophenylselenylation of glycals is described consisting of reaction with TMSN3 and Ph2Se2 in the presence of PhI(OAc)2. The use of TMSN3 instead of NaN3 as in the heterogeneous procedure, allowed both a reduced reaction time and a scale-up that was not possible in the case of the azidophenylselenylation of substituted glycals using NaN3.
Radical mediated synthesis of N-acetyl-D-galactosamine containing C-disaccharides via a temporary phosphoramidic connection
Rubinstenn, Gilles,Esnault, Jacques,Mallet, Jean-Maurice,Sinay, Pierre
, p. 1327 - 1336 (2007/10/03)
The C-disaccharide {α-D-GalNAc-C-(1→4)-β-D-Glc-OMe} and its interglycosidic β anomer were synthesized by radical coupling of phenyl 2-amino-3,4,6-tri-O-benzyl-2-deoxy-1-seleno-α-D-galactopyranoside onto methyl 2,6-di-O-benzyl-4-deoxy-4-C-methylene- β-D-xylo-hexopyranoside, which are temporarily connected through a phosphoramido tether. A similar reaction was performed with methyl 2,3-di-O-benzyl-4-deoxy-4-C-methylene-α-D-xylo-hexopyranoside to produce the two closely related α-OMe C-disaccharides.
Preparation of diversely protected 2-azido-2-deoxyglycopyranoses from glycals
Czernecki,Ayadi
, p. 343 - 350 (2007/10/03)
A new and efficient preparation of diversely protected 2-azido-2-deoxyglycopyranosides from the corresponding glycals is described. The glycals are first transformed into protected phenyl 2-azido-2-deoxy-selenoglycopyranosides by azido-phenylselenylation.
Selenoglycosides. 3. Synthesis of Phenyl 2-(N-Acetylamino)- and 2-Azido-2-deoxy-1-seleno-α-D-glycopyranosides via Azido-phenylselenylation of Diversely Protected Glycals
Czernecki, S.,Ayadi, E.,Randriamandimby, D.
, p. 8256 - 8260 (2007/10/02)
Two methods are described for the preparation of diversely protected phenyl 2-azido-2-deoxy-α-D-selenoglycopyranosides from protected glycals.In the first one (method A), a peracetylated glycal is treated with sodium azide and diphenyl diselenide in the presence of (diacetoxyiodo)benzene in dichloromethane at rt.With 3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-D-arabino-hex-1-enitol (tri-O-acetyl-D-glucal) an inseparable mixture of phenyl 2-azido-2-deoxy-α-gluco- and -α-manno-selenoglycosides is obtained (91percent yield).With 3,4,6-tri-O-acetyl-1,5-anhydro-2-deoxy-D-lyxo-hex-1-enitol (tri-O-acetyl-D-galactal) only the α-galacto isomer is obtained (92percent).Method A is not compatible with benzyl groups.In method B, a perbenzylated glycal is reacted with trimethylsilyl azide and tetra-n-butylammonium fluoride in the presence of N-phenylselenophthalimide.From protected D-glucal a gluco/manno mixture is obtained, whereas only the galacto isomer is formed from protected D-galactal (75percent yield).The compatibility of method B with a variety of protecting groups is exemplified with 6-O-acetyl, 6-O-benzyl, and 6-O-(tert-butyldimethylsilyl)-3,4-O-isopropylidene-1,5-anhydro-2-deoxy-D-lyxo-hex-1-enitol.The same diastereocontrol is observed, and the α-D-galacto isomer is obtained (60-70percent yield).Reduction of the azido group of these selenoglycosides with 1,3-propanedithiol in the presence of triethylamine and acetylation affords the corresponding phenyl 2-(N-acetylamino)-2-deoxy-α-D-selenoglycopyranosides in good yield.
New and Efficient Synthesis of Protected 2-Azido-2-deoxy-glycopyranoses from the Corresponding Glycal
Czernecki, Stanislas,Ayadi, Ebtissam,Randriamandimby, Dominique
, p. 35 - 36 (2007/10/02)
Diversely protected 2-azido-2-deoxy-D-glycopyranoses are prepared by azido phenylselenylation of the corresponding glycal followed by hydrolysis of the resulting selenoglycosides: from protected D-galactal, protected 2-azido-2-deoxy-D-galactopyranose is obtained, as the sole product in 72percent overall yield.
Azido-phenylselenylation of protected glycals
Czernecki,Randriamandimby
, p. 7915 - 7916 (2007/10/02)
Anti-Markovnikov azido-phenylselenylation of diversely protected glycals affords protected phenyl 2-azido-2-deoxy-α-selenoglycopyranosides. From D-glucal, the α-manno and α-gluco isomers are obtained, whereas from D-galactal, a complete stereocontrol is observed, affording exclusively the α-galacto isomer in 70% yield.
