(1-13C)Alditols: elimination of magnetic equivalence in 1H-and 13C-n.m.r. spectra of symmetric compounds through (13C)-substitution
作者:Eugenia C. Garrett、Anthony S. Serianni
DOI:10.1016/0008-6215(90)80082-e
日期:1990.12
(1-13C)Glycerol, D-(1-13C)arabinitol, D-(1-13C)ribitol, D-(1-13C)xylitol, D-(1-13C)glucitol, D-(1-13C)mannitol, and D-(1-13C)talitol have been prepared by NaBH4 reduction of the corresponding (1-13C)aldoses. A comparison of the 1H- (300 and 620 MHz) and 13C (75 MHz) n.m.r. spectra of natural and (1-13C)-substituted dissymmetric alditols has permitted the unequivocal assignments of their hydroxymethyl
(1-13C)甘油,D-(1-13C)阿拉伯糖醇,D-(1-13C)核糖醇,D-(1-13C)木糖醇,D-(1-13C)葡萄糖醇,D-(1-13C)甘露醇和D-(1-13C)塔罗糖醇已通过NaBH4还原相应的(1-13C)醛糖制备。比较天然和(1-13C)取代的不对称醛糖醇的1H-(300 MHz和620 MHz)和13C(75 MHz)nmr光谱,可以明确地确定其羟甲基质子和碳信号,并测量几种13C -1H和13C-13C自旋耦合常数。然而,(1-13C)取代的对称糖醇的相似光谱更难于解释,因为它们由重叠的13C耦合和13C非耦合子光谱组成。在某些情况下,可以使用1H差异光谱和1H耦合的13C光谱从13C耦合的组件中提取13C-1H和13C-13C自旋耦合。