Anion binding selectivity can often be controlled by judicious arrangement of recognition moieties
around an anion of interest. Indeed, nature takes advantage of large peptides/proteins to provide
highly efficient and selective anion receptors using a small number of amino acid building blocks
placed in a precise arrangement. Cyclic peptides are ideal synthetic scaffolds to position binding
residues in a similarly preorganised manner as their synthetic versatility and rigidified structure
allows precise control over their size and shape. This review summarises the recent use of such
cyclic peptide scaffolds as receptors for various anionic species.