Jain R K, Kohata K, Abbas S A, Matta K L
Department of Gynecologic Oncology, Roswell Park Memorial Institute, New York State Department of Health, Buffalo 14263.
Carbohydr Res. 1988 Jan 15;172(1):27-35. doi: 10.1016/s0008-6215(00)90841-3.
Benzylation of methyl 3-O-(2-acetamido-4,6-O-benzylidene-2-deoxy-beta-D- glucopyranosyl)-2,4,6-tri-O-benzyl-beta-D-galactopyranoside with benzyl bromide in N,N-dimethylformamide in the presence of sodium hydride afforded methyl 3-O- (2-acetamido-3-O-benzyl-4,6-O-benzylidene-2-deoxy-beta-D-glucopyranosyl) -2,4,6- tri-O-benzyl-beta-D-galactopyranoside (3). Reductive ring-opening of the benzylidene group of 3 gave methyl 3-O-(2-acetamido-3,6-di-O-benzyl-2-deoxy-beta-D- glucopyranosyl)- 2,4,6-tri-O-benzyl-beta-D-galactopyranoside (4). Cleavage of the 4,6-acetal group of 3 with hot, 80% aqueous acetic acid afforded the diol (5). Compounds 3, 4, and 5 were each subjected to halide ion-catalyzed glycosylation with 2,3,4-tri-O-benzyl-alpha-L-fucopyranosyl bromide to produce the corresponding trisaccharide derivatives, which, on catalytic hydrogenation, furnished the title trisaccharides, respectively.
在氢化钠存在下，3 - O -（2 - 乙酰氨基 - 4,6 - O - 亚苄基 - 2 - 脱氧 - β - D - 吡喃葡萄糖基）- 2,4,6 - 三 - O - 苄基 - β - D - 吡喃半乳糖苷甲酯与苄基溴在N，N - 二甲基甲酰胺中进行苄基化反应，得到3 - O -（2 - 乙酰氨基 - 3 - O - 苄基 - 4,6 - O - 亚苄基 - 2 - 脱氧 - β - D - 吡喃葡萄糖基）- 2,4,6 - 三 - O - 苄基 - β - D - 吡喃半乳糖苷甲酯（3）。3的亚苄基进行还原开环反应得到3 - O -（2 - 乙酰氨基 - 3,6 - 二 - O - 苄基 - 2 - 脱氧 - β - D - 吡喃葡萄糖基）- 2,4,6 - 三 - O - 苄基 - β - D - 吡喃半乳糖苷甲酯（4）。用热的80%乙酸水溶液裂解3的4,6 - 缩醛基团得到二醇（5）。化合物3、4和5分别与2,3,4 - 三 - O - 苄基 - α - L - 吡喃岩藻糖基溴进行卤离子催化的糖基化反应，生成相应的三糖衍生物，这些衍生物经催化氢化分别得到标题三糖。
