Ray A K, Magnusson G
Chemical Center, Lund Institute of Technology, University of Lund, Sweden.
Acta Chem Scand (Cph). 1992 May;46(5):487-91. doi: 10.3891/acta.chem.scand.46-0487.
The tri and tetra-saccharide glycosides beta-D-GalNAc-(1-4)-beta-D-Gal-(1-4)-beta-D-Glc-1-OTMSEt and beta-D-Gal-(1-3)-beta-D-GalNAc-(1-4)-beta-D-Gal-(1-4)-beta-D-Glc-1-OT MSEt (asialo-GM1) have been synthesized by sequential glycosylations of a suitably protected 2-(trimethylsilyl)ethyl (TMSEt) lactoside with 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-galactopyranosyl chloride and 2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl bromide. The tetrasaccharide glycoside was transformed into the corresponding hemiacetal sugar as well as the 1-chloro sugar. The latter was used for glycosylation of 2-bromoethanol. The resulting glycoside was used to alkylate methyl 3-mercaptopropionate and the resulting spacer glycoside was used for the preparation of the title glycoconjugates.
通过用3,4,6-三-O-乙酰基-2-脱氧-2-邻苯二甲酰亚氨基-β-D-吡喃半乳糖基氯和2,3,4,6-四-O-乙酰基-β-D-吡喃半乳糖基溴对适当保护的2-(三甲基甲硅烷基)乙基(TMSEt)乳糖苷进行连续糖基化反应，合成了三糖和四糖糖苷β-D-氨基半乳糖-(1→4)-β-D-半乳糖-(1→4)-β-D-葡萄糖-1-OTMSEt和β-D-半乳糖-(1→3)-β-D-氨基半乳糖-(1→4)-β-D-半乳糖-(1→4)-β-D-葡萄糖-1-OTMSEt(脱唾液酸GM1)。将四糖糖苷转化为相应的半缩醛糖以及1-氯糖。后者用于2-溴乙醇的糖基化反应。所得糖苷用于使3-巯基丙酸甲酯烷基化，所得间隔基糖苷用于制备标题糖缀合物。
