A steroid-based gelator of A(LS)2 type: tuning gel properties by metal coordination

Abstract

By utilizing up-to-date knowledge about gelators, we designed and synthesized a novel low-molecular-weight gelator bearing a pyridine-2,6-dicarboxylic acid moiety and two cholesteryl glycinate units. In order to demonstrate the ingenuity of our design, we prepared a series of structurally related compounds and studied their gelation properties. Based on the results, we determined structural features of the gelator molecules which were important for successful gel formation. We showed that the properties of the gel systems (transparency, morphology, etc.) can be tuned by coordination with different metal ions, as well as by changing the solvent. Gelators, and their gels and xerogels were studied by combined NMR spectroscopy, X-ray powder and single crystal diffractions, and electron microscopic techniques. Additionally, a systematic investigation of xerogels derived from silver metallogels revealed an in situ generation of silver nanoparticles.