Oxatub[4]arene was found to be able to host a wide range of organic cations. This strong binding ability is believed to originate from its four interconvertible and deep-cavity conformers.
the repeat units in oxatub[4]arene and zorb[4]arene, and its recognition behavior and conformational analysis were studied. Three structurally similar and conformationally adaptive macrocycles show different guest-binding selectivities and preferences even in a complex mixture containing three macrocycles and three guests.