Synthesis of new amphiphilic Zn-salophen complexes derivatized by bile acids

The amphiphilic Zn-salophen complexes have lately been receiving attention due to their aggregation behaviour, dependent upon some experimental parameters, such as concentration and polarity of solvents. The possibility to control their aggregation morphologies, and their well known capability to accept one axially coordinated donor species make them suitable candidates for the development of new materials with applications in sensing. The search of new amphiphilic derivatives of Zn-salophenes is thus an active research field. Our group have recently been working on the functionalization of bile acids which are an important class of natural surfactants showing amphiphilic properties strictly related to their rigid backbones. We prepared new derivatives linking natural bile acids to other natural compounds, such as sugars and aminoacids. The aggregation properties of the resulting derivatives were studied, and interesting aggregates and nanostructures were observed, making these compounds ideal building blocks for the bottom up synthesis of new materials for applications in the field of materials chemistry, in pharmacology and in the field of nanotechnologies, also thanks to the morphological variability. Thus here we describe the functionalization of metal-salophen complexes with substituted bile acids to obtain complex derivatives, in principle able to aggregate both thanks to the metal salophenic core, and bile acid subunit. The strategies to functionalize bile acid backbone at C-3 or at its side chain are discussed.