Diastereospecific synthesis and amphiphilic properties of new alkyl beta-D-fructopyranosides

In this article we describe a novel one step stereocontrolled synthesis of alkyl 1-O-beta-D-fructopyranosides from totally unprotected D-fructose. In order to avoid oligomerization of D-fructose the reactions were performed i n heterogeneous media. Thus, long chain alcohols, as accepters, were treate d with D-fructose in the presence of iron(III) chloride as the promoter to give the alkyl substituted products in yields of approximately 30%. The mat erials produced were found to self-organise and form liquid crystal mesopha ses. One of the thermotropic phases exhibited by this family of compounds w as found to be atypical of liquid crystal modifications normally exhibited by glycolipids. The structure of this phase was investigated by a wide vari ety of techniques, and sufficient evidence was gained to indicate that it i s novel. A variety of possible arrangements of the molecules in the self-or ganised state is given based on the preliminary data.