Paulsen H, Bünsch A
Carbohydr Res. 1982 Mar 1;100:143-67. doi: 10.1016/s0008-6215(00)81032-0.
The pentasaccharide chain of the Forssman antigen, O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-(1 leads to 3)-O-(2-acetamido-2-deoxy-beta-D-galactopyranosyl)-(1 leads to 3)-O-alpha-D-galactopyranosyl-(1 leads to 4)-O-beta-D-galactopyranosyl-(1 leads to 4)-D-glucopyranose (46) was synthesized by a block synthesis in which an alpha-D-glycoside linkage between two D-galactose residues was formed. The trisaccharide O-(6-O-acetyl-2-azido-3,4-di-O-benzoyl-2-deoxy-alpha-D-galactopyranosyl)-(1 leads to 3)-O-(6-O-acetyl-4-O-bebenzyl-2-deoxy-2-phthalimido-beta-D-galactopyranosyl)-(1 leads to 3)-6-O-acetyl-2,4-di-O-benzyl-alpha-D-galactopyranosyl bromide (40) (this was obtained through acetolysis of O-(6-O-acetyl-2-azido-3,4-di-O-benzoyl-2-deoxy-alpha-D-galactopyranosyl)-(1 leads to 3)-O-(6-O-acetyl-4-O-benzyl-2-deoxy-2-phthalimido-beta-D-galactopyranosyl)-(1 leads to 3)-1,6-anhydro-2,4-di-O-benzyl-beta-D-galactopyranose to the acetyl derivative, followed by reaction with titanium tetrabromide under anhydrous conditions) was condensed with benzyl-4-O-)6-O-benzoyl-2,3-di-O-benzyl-beta-D-galactopyranosyl)-2,3,6-tri-O-benzyl-beta-D-glucopyranoside were in the presence of silver carbonate and perchlorate. The resulting pentasaccharide was deprotected to give 46.
福斯曼抗原的五糖链，即O-(2-乙酰氨基-2-脱氧-α-D-吡喃半乳糖基)-(1→3)-O-(2-乙酰氨基-2-脱氧-β-D-吡喃半乳糖基)-(1→3)-O-α-D-吡喃半乳糖基-(1→4)-O-β-D-吡喃半乳糖基-(1→4)-D-吡喃葡萄糖（46），是通过一种片段合成法合成的，其中在两个D-半乳糖残基之间形成了α-D-糖苷键。三糖O-(6-O-乙酰基-2-叠氮基-3,4-二-O-苯甲酰基-2-脱氧-α-D-吡喃半乳糖基)-(1→3)-O-(6-O-乙酰基-4-O-苄基-2-脱氧-2-邻苯二甲酰亚氨基-β-D-吡喃半乳糖基)-(1→3)-6-O-乙酰基-2,4-二-O-苄基-α-D-吡喃半乳糖基溴化物（40）（这是通过将O-(6-O-乙酰基-2-叠氮基-3,4-二-O-苯甲酰基-2-脱氧-α-D-吡喃半乳糖基)-(1→3)-O-(6-O-乙酰基-4-O-苄基-2-脱氧-2-邻苯二甲酰亚氨基-β-D-吡喃半乳糖基)-(1→3)-1,6-脱水-2,4-二-O-苄基-β-D-吡喃半乳糖进行乙酰解反应得到乙酰衍生物，然后在无水条件下与四溴化钛反应而获得）在碳酸银和高氯酸盐存在下与苄基-4-O-( )6-O-苯甲酰基-2,3-二-O-苄基-β-D-吡喃半乳糖基)-2,3,6-三-O-苄基-β-D-吡喃葡萄糖苷缩合。所得五糖经脱保护得到46。
