C2-symmetrical sterol-polyether conjgates as highly efficient synthetic ionophores

A new class of artificial ionophores has been rationally designed and synthesized linking to a tetrafunctionalized L-treitol spacer two rigid hydrophobic 3ƒÒ-hydroxy-5ƒÑ-23,24-bisnorcholanic units and two flexible hydrophilic oligo(ethyleneglycol) chains. Compounds 1a and 1b were incorporated into phospholipid vesicles and shown to facilitate Na+-transport