Synthesis of unsymmetrical saturated or diacetylenic cationic bolaamphiphiles
摘要:
This work presents the synthesis of novel unsymmetrical bolaamphiphiles bearing a sugar residue and a cationic glycine betaine moiety connected to both ends of a C-22 or C-32 oligomethylene bridging chain possessing or not a diacetylenic unit. Preliminary transmission electron microscopy (TEM) studies revealed the polymorphism of these bola lipids with regard to their self-assembled morphologies in water depending on the presence or not of the diacetylenic functionality and on alkyl chain length. (C) 2008 Elsevier Ltd, All rights reserved.
展示了三组分别在 C3-C4、C2-C3 和 C1-C2 键上旋转自由度受限的呋喃糖。这些呋喃糖的构象分析基于质子核磁共振 ( 1 H NMR) 光谱、密度泛函理论 (DFT) 计算和 X 射线分析进行。结果表明,所呈现的呋喃糖的特定组被锁定在特定的构象中。它们分别是1 T 2样、0 E样和3 T 4样构象。特点1介绍了这三种构象的 H NMR 光谱,并讨论了影响分析的呋喃糖构象偏好的因素。