“…In this sense, molecular calixarenes constitute a suitable family of macrocyclic oligomers for anion recognition, owing to their convenient cavity shape. − Specifically, [1 n ]metacyclophanes, in which the aromatic units of the calixarenes are linked by methylene bridges in ortho position (Figure ). , Their typical framework, which resembles a cone shaped calix, allows their use for a wide range of applications, such as selective removal of ions from aqueous media, − as drug carrier agents, and in the preparation of synthetic ionic channels, , pores and membranes, − besides their use in catalysis. − …”