Liu J, Waterhouse A L, Chatterton N J
Department of Viticulture and Enology, University of California, Davis 95616.
Carbohydr Res. 1993 Jul 5;245(1):11-9. doi: 10.1016/0008-6215(93)80056-k.
The proton chemical-shift assignment of nystose (1) [beta-D-fructofuranosyl-(2-->1)-beta-D-fructofuranosyl-(2-->1)-beta-D- fructofuranosyl-(2<==>1)-alpha-D-glucopyranoside], was determined by using two-dimensional (2D) NMR spectral methods, and corrections of, and additions to the previous 13C chemical-shift assignments were made. The 1H peak of H-1 of the D-glucosyl group was determined by its chemical shift. Signals from fructose-1 were distinguished by the observation of long-range C-H coupling between H-1 of the D-glucosyl group and C-2 of fructose-1. The distinction between fructose-2 and fructose-3 was made by the different 1JCH coupling patterns between C-1 and H-1. Assignments of 13C and 1H chemical shifts of the related dp 5 compound, beta-D-fructofuranosyl-(2-->1)-beta-D-fructofuranosyl-(2-->1)-beta-D- fructofuranosyl-(2-->1)-beta-D-fructofuranosyl-(2<==>1)-alpha-D-glucopyr anoside (1,1,1-kestopentaose, 2) are also reported here with comparisons of its spectral data with the data from 1-kestose, nystose and inulin. Based on differences in 13C chemical shifts, it appears that the chemical environment of inulin is not attained in nystose, and only partially attained in 1,1,1-kestopentaose.
通过使用二维（2D）核磁共振光谱方法确定了蔗果三糖（1）[β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-(2⇔1)-α-D-吡喃葡萄糖苷]的质子化学位移归属，并对先前的¹³C化学位移归属进行了修正和补充。D-葡萄糖基的H-1的¹H峰通过其化学位移确定。通过观察D-葡萄糖基的H-1与果糖-1的C-2之间的远程C-H耦合来区分来自果糖-1的信号。通过C-1和H-1之间不同的¹JCH耦合模式区分果糖-2和果糖-3。还报道了相关的dp 5化合物β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-(2⇔1)-α-D-吡喃葡萄糖苷（1,1,1-蔗果五糖，2）的¹³C和¹H化学位移归属，并将其光谱数据与蔗果六糖、蔗果三糖和菊粉的数据进行了比较。基于¹³C化学位移的差异，似乎在蔗果三糖中未达到菊粉的化学环境，而在1,1,1-蔗果五糖中仅部分达到。
