51996-10-2Relevant academic research and scientific papers
Rapid and efficient synthesis of α(1-2)mannobiosides
Reina, José J.,Di Maio, Antonio,Ramos-Soriano, Javier,Figueiredo, Rute C.,Rojo, Javier
, p. 2873 - 2882 (2016/03/12)
α(1,2)mannobiosides with different substituents at the reducing end have been synthesized by a common strategy using benzoyls as the permanent protecting groups and an acetyl as the orthogonal protecting group at position C2 of the glycosyl acceptor. The
Unexpected stereocontrolled access to 1α,1′β-disaccharides from methyl 1,2-ortho esters
Uriel, Clara,Ventura, Juan,Gomez, Ana M.,Lopez, J. Cristobal,Fraser-Reid, Bert
experimental part, p. 795 - 800 (2012/03/22)
Mannopyranose-derived methyl 1,2-orthoacetates (R = Me) and 1,2-orthobenzoates (R = Ph) undergo stereoselective formation of 1α,1′β-disaccharides, upon treatment with BF 3?Et2O in CH2Cl2, rather than the expected acid-catalyzed reaction leading to methyl glycosides by way of a rearrangement-glycosylation process of the liberated methanol.
Studies on the stereoselective synthesis of a protected α-D-Gal-(1→2)-D-Glc fragment
Chen, Langqiu,Shi, Shen-De,Liu, Yong-Qing,Gao, Qing-Jiao,Yi, Xing,Liu, Kai-Ke,Liu, Hao
, p. 1250 - 1256 (2011/07/09)
A novel 1,2-cis stereoselective synthesis of protected α-D-Gal- (1→2)-D-Glc fragments was developed. Methyl 2-O-acetyl-3-O-allyl-4,6-O- benzylidene-α-D-galactopyranosyl-(1→2)-3-O-benzoyl-4, 6-O-benzylidene-α-D-glucopyranoside (13), methyl 2-O-acetyl-3-O-allyl-4,6- O-benzylidene-α-D-galactopyranosyl-(1→2)-3,4,6-tri-O-benzoyl-α- D-glucopyranoside (15), methyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-α-D- galactopyranosyl-(1→2)-3-O-benzoyl-4,6-O-benzylidene-β-D- glucopyranoside (17), and methyl 2-O-acetyl-3-O-allyl-4,6-O-benzylidene-α- D-galactopyranosyl-(1→2)-3,4,6-tri-O-benzoyl-β-D-glucopyranoside (19) were favorably obtained by coupling a new donor, isopropyl 2-O-acetyl-3-O-allyl- 4,6-O-benzylidene-1-thio-β-D-galactopyranoside (2), with acceptors, methyl 3-O-benzoyl-4,6-O-benzylidene-α-D-glucopyranoside (4), methyl 3,4,6-tri-O-benzoyl-α-D-glucopyranoside (5), methyl 3-O-benzoyl-4,6-O- benzylidene-β-D-glucopyranoside (8), and methyl 3,4,6-tri-O-benzoyl-β- D-glucopyranoside (12), respectively. By virtue of the concerted 1,2-cis α-directing action induced by the 3-O-allyl and 4,6-O-benzylidene groups in donor 2 with a C-2 acetyl group capable of neighboring-group participation, the couplings were achieved with a high degree of α selectivity. In particular, higher α/β stereoselective galactosylation (5.0:1.0) was noted in the case of the coupling of donor 2 with acceptor 12 having a β-CH3 at C-1 and benzoyl groups at C-4 and C-6.
Application of the hydrogenphosphonate approach in the synthesis of glycosyl phosphosugars linked through secondary hydroxyl groups
Nikolaev, Andrey V.,Ivanova, Irena A.,Shibaev, Vladimir N.,Kochetkov, Nikolay K.
, p. 65 - 78 (2007/10/02)
The hydrogenphosphonate approach has been used in syntheses of methyl α-D-mannopyranoside 2-, 3-, and 4-(α-D-mannopyranosyl phosphate), benzyl β-D-galactopyranoside 2-(α-D-mannopyranosyl phosphate), and methyl β-D-galactopyranoside 4-(α-D-mannopyranosyl phosphate).Condensation of 2,3,4,6-tetra-O-benzyl- or 2,3,4,6-tetra-O-benzoyl-α-D-mannopyranosyl hydrogenphosphonate with suitable, partially acylated monohydroxy derivatives in the presence of Me3CCOCl, followed by oxidation of the resulting hydrogenphosphonate diesters with iodine, gave the O-protected phosphate diesters in yields of 67-87percent.Deprotection then gave the glycosyl phosphosugars.
