Concise synthesis of a tetrasaccharide related to the repeating unit of the cell wall O-antigen of Salmonella enterica O60. Issue 34 (21st August 2020)

• Record Type: Journal Article
• Authors: Gucchait, Arin; Shit, Pradip; Misra, Anup Kumar
• Is Part Of: Tetrahedron. Volume 76:Issue 34(2020)
• Publication Date: 2020-08-21
• Subjects: Tetrasaccharide -- Glycosylation -- Beta-mannoside -- 3-Amino-3-deoxy-d-fucose -- Salmonella enterica O60; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2020.131412
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: Synthesis of a tetrasaccharide related to the repeating unit of the cell wall O -antigen of Salmonella enterica O60 has been achieved by sequential glycosylations in very good yield. Use of p -methoxybenzyl group (PMB) as an in situ removable protecting group allowed obtaining the desired compound in less number of steps. Synthesis of a beta-D-mannosidic linkage present in the molecule has been successfully achieved using d -mannosyl thioglycoside donor having a p -methoxybenzyl (PMB) group at remote C-3 position. A combination of N -iodosuccinimide (NIS) and perchloric acid supported over silica (HClO4 –SiO2 ) has been used as thiophilic glycosylation promoter in glycosylation reactions. Thioglycoside of 3-amino-3-deoxy-d -fucose has been prepared and used in the synthetic scheme for its incorporation in α-glycosidic linkage. Graphical abstract: Image 1 Highlights: Tetrasaccharide related to the cell wall of Salmonella enterica O60 was synthesized. A combination of NIS and HClO4 –SiO2 has been used as glycosylation activator. 3-Amino-3-deoxy-d -fucosyl thioglycoside has been prepared from d -fucose. PMB group directed glycosylation has been used to achieve β-mannosidic linkage. The number of reaction steps was reduced by using in situ removable PMB group.