beta-D-ManpNac-(1----4)-D- Glcp. The derivatives were activated into disaccharide halides and employed as glycosyl donors in block synthesis. By chain extension with L-rhamnose and D-glucose, four trisaccharides were synthesized. They represent components of capsular polysaccharide "repeating units" of various Streptococcus pneumoniae types, beta-D-Man-pNAc-(1----4)-alpha-D-Glcp-(1----2)-L-Rhap (type 19 F), beta
在
硅酸银作为
促进剂的存在下,2-
叠氮基-2-脱氧-
D-甘露糖的糖基
溴化物与1,6-脱
水-2,3-二-O-苄基-β-
D-吡喃葡萄糖反应二糖β-D-ManpNac-(1 ---- 4)-D-Glcp的衍
生物。衍
生物被活化成二糖卤化物,并用作嵌段合成中的糖基供体。通过
L-鼠李糖和
D-葡萄糖的扩链,合成了四个三糖。它们代表各种肺炎链球菌类型的荚膜
多糖“重复单元”的成分,β-D-Man-pNAc-(1 ---- 4)-alpha-D-Glcp-(1 ---- 2)-L- Rhap(19 F型),beta-D-ManpNAc-(1 ---- 4)-alpha-D-Glcp-(1 ---- 3)-L-Rhap(19 A型),beta-D- ManpNAc-(1 ---- 4)-alpha-D-Glcp-(1 ---- 4)-D-Glcp(9 A型)和beta-D-ManpNAc-(1 ---- 4) -beta-D-Glcp-(1