Journal of Organic Chemistry p. 11237 - 11257 (2015)
Update date:2022-08-15
Topics:
Salamone, Stéphane
Guerreiro, Catherine
Cambon, Emmanuelle
Hargreaves, Jason M.
Tarrat, Nathalie
Remaud-Siméon, Magali
André, Isabelle
Mulard, Laurence A.
Chemo-enzymatic strategies hold great potential for the development of stereo- and regioselective syntheses of structurally defined bioactive oligosaccharides. Herein, we illustrate the potential of the appropriate combination of a planned chemo-enzymatic pathway and an engineered biocatalyst for the multistep synthesis of an important decasaccharide for vaccine development. We report the stepwise investigation, which led to an efficient chemical conversion of allyl α-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3)-2-deoxy-2-trichloroacetamido-β-d-glucopyranoside, the product of site-specific enzymatic α-d-glucosylation of a lightly protected non-natural disaccharide acceptor, into a pentasaccharide building block suitable for chain elongation at both ends. Successful differentiation between hydroxyl groups features the selective acylation of primary alcohols and acetalation of a cis-vicinal diol, followed by a controlled per-O-benzylation step. Moreover, we describe the successful use of the pentasaccharide intermediate in the [5 + 5] synthesis of an aminoethyl aglycon-equipped decasaccharide, corresponding to a dimer of the basic repeating unit from the O-specific polysaccharide of Shigella flexneri 2a, a major cause of bacillary dysentery. Four analogues of the disaccharide acceptor were synthesized and evaluated to reach a larger repertoire of O-glucosylation patterns encountered among S. flexneri type-specific polysaccharides. New insights on the potential and limitations of planned chemo-enzymatic pathways in oligosaccharide synthesis are provided.
View MoreContact:852-27701081
Address:Room 2509, New Tech Plaza, 34 Tai Yau St., San Po Kong, HK
Shandong Topscience Biotech Co., Ltd.
Contact:0633-2619278
Address:No. 98 Lanshan West Road, Lanshan District, Rizhao, Shandong Province, P.R. of China
Huangshan Honghui Pharm Technology Co., Ltd.(expird)
website:http://www.honghuichem.com
Contact:18855958372
Address:Qingshan Wan No.1,Nanyuan Kou,SheXian Huangshan City,Anhui Province
Sichuan WeiKeqi Biological Technology Co., Ltd.
Contact:86-028-81700200
Address:sichuan Chengdu Qingjiang Zhonglu 63号
guide(suzhou) fine materials co. ltd
Contact:0512-80972173
Address:21st Building, No.369 Lushan Rd, New District Suzhou China 215129
Doi:10.1002/chem.200305682
(2004)Doi:10.1021/jo00398a023
(1978)Doi:10.1039/P19720002663
(1972)Doi:10.1039/c6md00236f
(2016)Doi:10.1021/jo035068m
(2003)Doi:10.1021/ja403007r
(2013)