6-di-O-benzylidene-α- d -mannofuranoside and methyl 2,3-O-benzylidene-α- l -rharmnofuranoside were prepared according to a new procedure by simultaneous glycosidation and acetalation of d -mannose and l -rhamnose. Treatment of these compounds and of 1,6-anhydro-2,3-O-benzylidene- d -mannose with N-bromosuccinimide gave exclusively the 3-bromo compounds by regiospecific opening of the acetal ring. Thus, starting from
摘要通过同时糖化和
乙缩醛缩醛化的新方法,制备了甲基2,3:5,6-二-O-亚苄基-α-d-甘露
呋喃糖苷和甲基2,3-O-亚苄基-α-1-L-
呋喃呋喃糖苷。 -
甘露糖和l-
鼠李糖。用N-
溴代琥珀
酰亚胺处理这些化合物和1,6-脱
水-2,3-O-亚苄基-d-
甘露糖,通过
缩醛环的区域特异性开放仅得到3-
溴化合物。因此,从
鼠李糖开始,以七个步骤制备了N-乙酰基-1-霉豆胺(3-
氨基-3,6-二脱氧-1-
甘露糖),总产率为32%。