Oxacalix[n](het)arenes.

Oxacalix[n]arenes, reassessed members of the calixarene family in which the traditional methylene bridges are replaced by oxygen atoms, have emerged as a promising class of macrocycles in recent years. This tutorial review summarizes the synthetic progress made in the field during the last few years and aims to stimulate its current evolution from a merely synthetic to a more applied branch of macro- and supramolecular chemistry.