Anion hosts biological receptors

These problems have been addressed in a wide variety of imaginative and novel ways and progress in anion complexation has been rapid in recent years " to the extent that it has now been described by Lehn as a full member of the field of supramolecular chemistry. It is important to note that the search for anion-selective receptors has not been limited to the mimicry of Mother Nature s approach. Indeed, a great number of the hosts developed are far from being biocompatible as the tools of the chemist are not limited to the building blocks of natural systems. This aspect of anion recognition chemistry lies at the heart of supramolecular chemistry, the interface between chemistry and biology. ... 

A cascade receptor is a host that binds one of more metal ions which, in turn, bind anions. They are of interest in the modelling of biological metal-based active sites — metallobiosites. 

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