Kaifu R, Osawa T
Carbohydr Res. 1976 Dec;52:179-85. doi: 10.1016/s0008-6215(00)85958-3.
2-Methyl-[3,6-di-O-acetyl-2-deoxy-4-O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-alpha D-glucopyrano]-[2,1-d]-2oxazoline (4) was prepared from 2-acetamido-3,6-di-O-acetyl-2-deoxy-4-O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-alpha-D-glucopyranosyl chloride. Condensation of 3,4:5,6-di-O-isopropylidene-D-mannose dimethyl acetal with 4 in the presence of a catalytic amount of p-toluenesulfonic acid afforded O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-(1 linked to 4)-O-(2-acetamido-3,6-di-O-acetyl-2-deoxy-beta-D-glucopyranosyl)-(1 linked to 2)-3,4:5,6-di-O-ispropylidene-D-mannose dimethyl acetal (6) in 8.6% yield. Catalytic deacetylation of 6 with sodium methoxide, followed by hydrolysis with dilute sulfuric acid, gave O-beta-D-galactopyranosyl-(1 linked to 4)-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-(1 linked to 2)-D-mannose (7). The inhibitory activities of 7 and related sugars against the henagglutinating activities of various lectins were assayed, and 7 was found to be a good inhibitor against Phaseolus vulgaris hemagglutinin.
2-甲基-[3,6-二-O-乙酰基-2-脱氧-4-O-(2,3,4,6-四-O-乙酰基-β-D-吡喃半乳糖基)-α-D-吡喃葡萄糖基]-[2,1-d]-2-恶唑啉(4)由2-乙酰氨基-3,6-二-O-乙酰基-2-脱氧-4-O-(2,3,4,6-四-O-乙酰基-β-D-吡喃半乳糖基)-α-D-吡喃葡萄糖基氯制备。在催化量的对甲苯磺酸存在下，3,4:5,6-二-O-异亚丙基-D-甘露糖二甲基缩醛与4缩合，得到O-(2,3,4,6-四-O-乙酰基-β-D-吡喃半乳糖基)-(1连接到4)-O-(2-乙酰氨基-3,6-二-O-乙酰基-2-脱氧-β-D-吡喃葡萄糖基)-(1连接到2)-3,4:5,6-二-O-异亚丙基-D-甘露糖二甲基缩醛(6)，产率为8.6%。6用甲醇钠进行催化脱乙酰化，然后用稀硫酸水解，得到O-β-D-吡喃半乳糖基-(1连接到4)-O-(2-乙酰氨基-2-脱氧-β-D-吡喃葡萄糖基)-(1连接到2)-D-甘露糖(7)。测定了7和相关糖类对各种凝集素的血凝活性的抑制活性，发现7是菜豆血凝素的良好抑制剂。
