Nie Xiaoping, Wang Guijun
Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA.
J Org Chem. 2006 Jun 23;71(13):4734-41. doi: 10.1021/jo052317t.
Diacetylene-containing glycolipids are interesting molecules that have many potential applications. The polydiacetylenes formed by the cross-linking of the diacetylene lipids are new stimuli-responsive materials. In particular, diacetylene lipids that can form gels in aqueous solution are of great interest in designing functional biocompatible materials. We have synthesized a series of diacetylene-containing sugar lipids with different chain lengths, substituents, and positions of diyne and studied their self-assembling properties in several solvents including hexane, ethanol, and ethanol/water mixture. Among the 24 diacetylene-containing glycolipids synthesized, many of them exhibited excellent gelation properties in ethanol or ethanol/water mixture. Typically very long chain diacetylene lipids formed gels in ethanol and hexane. Shorter chain diacetylene lipids and compounds with one free hydroxyl group can form gels in aqueous solution. The position of the diyne and chain length affect the self-assembling properties significantly. The systematic study of the gelation properties for diacetylene lipids with different lipid chains can help us to understand the structure requirement for the desired physical properties. Optical microscopy studies showed that the molecules form interesting architectures such as tubules, rods, sheets, and belts. The resulting organogels can also be cross-linked and give different colored polymerized gels depending on their structures.
含二乙炔的糖脂是一类具有许多潜在应用价值的有趣分子。由二乙炔脂质交联形成的聚二乙炔是新型的刺激响应材料。特别地，能够在水溶液中形成凝胶的二乙炔脂质在设计功能性生物相容性材料方面具有极大的吸引力。我们合成了一系列具有不同链长、取代基以及二炔位置的含二乙炔糖脂，并研究了它们在包括己烷、乙醇以及乙醇/水混合物在内的多种溶剂中的自组装性质。在合成的24种含二乙炔糖脂中，许多在乙醇或乙醇/水混合物中表现出优异的凝胶化性质。通常，非常长链的二乙炔脂质能在乙醇和己烷中形成凝胶。较短链的二乙炔脂质以及带有一个游离羟基的化合物能在水溶液中形成凝胶。二炔的位置和链长对自组装性质有显著影响。对具有不同脂质链的二乙炔脂质的凝胶化性质进行系统研究有助于我们理解所需物理性质的结构要求。光学显微镜研究表明，这些分子形成了诸如小管、棒状、片状和带状等有趣的结构。所得的有机凝胶也可以交联，并根据其结构形成不同颜色的聚合凝胶。
