two latter C-α-d-mannopyranosyl scaffolds by acid hydrolysis into respective reactive free amine or aldehyde forms were developed as well. Detailed reinvestigation of the classical method of preparation of d-mannosyl nitromethanes by thermal dehydration of a 1-deoxy-1-nitroalditol derived from d-mannose showed a maximum occurrence of only 18% of the required α-d-mannopyranosyl anomer. Graphic abstract
抽象的对照治疗3,4,5,6,7-五ø -乙酰基-1,2-二脱氧-1-硝基d -manno -庚-1- enitol用在
甲醇中的
甲醇钠被去阳离子化的点处停止提供约等摩尔的α - d-
甘露聚糖基和β - d-
甘露聚糖基
硝基甲烷的混合物,通过
化学吸附色谱法在阳离子交换
树脂上以Ba 2+形式分离目标α-异头物,收率为36%。将上述混合物与
氢氧化亚铁直接还原为相应的胺,然后进行选择性N-乙酰化和具有稳定环结构的两个相关异构体的类似色谱分离,得到N-乙酰基-C - α - d-甘露
吡喃糖基-甲基胺。初始环形成与上述给定的产品比酸化
甲醇反应的替代停止发起随后的夫反应和α - d -mannopyranosyl
甲醛二甲基
乙缩醛,然后色谱从其分离β异构体上的OH阴离子交换
树脂-形式。后两个C - α - d的活化还开发了通过酸
水解成相应的反应性游离胺或醛形式的-甘露
吡喃糖基支架。通过热脱
水衍生自d-
甘露糖