Synthesis of 3-aminopropyl β-(1 → 6)-d-glucotetraoside and its biotinylated derivative

2-O-N-Benzylcarbamoyl as a Protecting Group To Promote β-Selective Glycosylation and Its Applications in the Stereoselective Synthesis of Oligosaccharides

“…62 This process was efficient; however, further elongation at the nonreducing end required acid-promoted deprotection at the 6-position, which might break down the glycosidic bond, or result in the acyl migration. 63,64 Trichloroacetimidate donor 27 was glycosylated with glycosyl acceptor 22 in the presence of TMSOTf to give compound 56 in 86% yield (exclusively β form). Removal of the acetyl group of 56 was accomplished using 1.0 N NaOH to give 57.…”

“…In previous work, elongation of the β-1,6 glycosylic bond of the β-1,6-glucan was achieved by selective protection of the 6-hydroxyl group with an acid labile protecting group, and protection of the 2-hydroxyl group with an ester protecting group . This process was efficient; however, further elongation at the nonreducing end required acid-promoted deprotection at the 6-position, which might break down the glycosidic bond, or result in the acyl migration. , Trichloroacetimidate donor 27 was glycosylated with glycosyl acceptor 22 in the presence of TMSOTf to give compound 56 in 86% yield (exclusively β form). Removal of the acetyl group of 56 was accomplished using 1.0 N NaOH to give 57 .…”

Noncatalytic selective 6-O-acetylation of methyl 2,3-di-O-benzoyl-α-d-glucopyranoside with acetic acid and acetic anhydride

“…This compound is supposed to be used for the introduction of an azide group at the C(4) atom with the formation of 4-azido-4-deoxygalactose derivative, 7 a precursor for the synthesis of containing 4-amino-4-deoxygalactose moiety analogs of cyclic oligosaccharides obtained earlier, 8 as well as oligomeric blockers of bacterial adhesins, 9 ion channels, 10,11 and other molecular systems. 12 In addition, glucose derivatives selectively acetylated at the O(6) atom, similar to compound 3, are convenient blocks for the assembly of β-(1→6)-linear 13 and β-(1→3),(1→6)branched 14,15 oligoglucosides corresponding to the fragments of β-glucans of the cell wall of fungi 16,17 of the genera Candida, Aspergillus, and others.…”

“…NMR spectra were recorded at 25 °C on a Bruker Avance 600 spectrometer in deutero chloroform (CDCl 3 ). Residual non-deuterated CHCl 3 (δ H 7.27) was used as an internal standard for 1 Н NMR spectra, the signal of CDCl 3 (δ C 77.0) was used as a reference for 13 C NMR spectra. The signal assignment was carried out using 2D COSY and HSQC correlation NMR spectroscopy.…”

Progress and challenges in the synthesis of sequence controlled polysaccharides

“…The primary C-6 hydroxy group is more nucleophilic than the secondary hydroxy group at C-3 and β-selectivity is easily achieved with the help of anchimeric assistance provided by a 2-O-acyl functionality. Despite these advantages, the synthesis of β(1-6)-Glc polysaccharides appears only in few reports [148,149], with short oligomers being prepared mainly to prove new methodologies [31,[150][151][152][153][154][155].…”