The products of Fischer's methyl glycosylation of 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN) revealed existence of an the anomeric equilibrium between α, β-furanose and α, β-pyranose of KDN. In spite of the anomeric equilibrium, peracetylation of KDN and its derivatives by acetic anhydride with pyridine gave only α- and β-pyranose derivatives. The obtained methyl glycosides and hexa-O-acetyl derivatives were characterized by X-ray, nuclear magnetic resonance and cicular dichroism spectral analyses.
3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN)的费舍尔甲基糖基化产物表明,KDN 的 α, β-
呋喃糖和 α, β-
吡喃糖之间存在着异构体平衡。尽管存在同分异构平衡,但用
乙酸酐与
吡啶对 KDN 及其衍
生物进行过乙酰化反应只能得到 α 和 β-
吡喃糖衍
生物。获得的甲基苷和六-O-乙酰基衍
生物通过 X 射线、核磁共振和立体二色光谱分析进行了表征。