The invention relates to a method of preparation of 6-azido-2,4-diacetamido-2,4,6-trideoxy-D-mannose.
This method comprises the chemical reaction of compound of formula X:
Wherein:
R1 can be a C1 to C6 alkyl including methyl, ethyl, isopropyl; aryl including phenyl; each of these groups being substituted or not;
and R2 can be a C1 to C6 alkyl including methyl, ethyl, isopropyl, tert-butyl, isobutyl; each of these groups being substituted or not;
with a deprotecting reagent comprising a Lewis or Brönsted acid in a polar aprotic solvent, thereby obtaining a free C-1 OH group.
The method can also start with the preparation from commercially available D-galactose pentaacetate, D-galactose tetraacetate or tetraacetyl D-galactosyl trichloroacetimidate.
According to the invention the step of deprotecting the anomeric position avoids the use of cerium and allows the easy purification of 6-azido-2,4-diacetamido-2,4,6-trideoxy-D-mannose.
本发明涉及一种制备 6-
叠氮-2,4-
二乙酰氨基-2,4,6-三脱氧-
D-甘露糖的方法。
该方法包括式 X 的化合物的
化学反应:
其中
R1 可以是包括甲基、乙基、异丙基在内的 C1 至 C6 烷基;包括苯基在内的芳基;这些基团中的每个基团均可被取代或未被取代;
R2 可以是 C1 至 C6 烷基,包括甲基、乙基、异丙基、叔丁基、异丁基;每个基团均被取代或未被取代;
在极性钝化溶剂中,用由
路易斯酸或勃氏酸组成的脱保护试剂,从而获得游离的 C-1 OH 基团。
该方法也可以从市售的
D-半乳糖五
乙酸酯、
D-半乳糖四乙酸酯或
D-半乳糖基
三氯乙酸亚
氨酸
四乙酸酯开始制备。
根据本发明,去保护同分异构体位置的步骤避免了
铈的使用,并使 6-
叠氮-2,4-
二乙酰氨基-2,4,6-三脱氧-
D-甘露糖易于纯化。