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:+86-574- 87178138; 87297407
Address:No. 809, Liudingxingzuo, cangsong road, Ningbo, China
website:http://www.hope-chem.com
Contact:86-21-58090396-805
Address:Floor 4, Building 5, No.588 Tianxiong Road, Zhoupu International Medical Zone, ShangHai, China
Shijiazhuang Haotian Chemical Co., Ltd.
Contact:86-311-85044374
Address:293 Donggang Road
changsha chenjin chemical technology co.,LtD(expird)
Contact:86-731-84451263
Address:Room 201/217-218, 101 Jingyuan Electronic Technology Co.,Ltd. Testing Center, No.69, Lufeng Road, High-tech Development Zone, Changsha, China
Contact:
Address:No.89,Xinhua Road, Langfang City,Hebei China
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)