Fig. 1: Structure of Octacid4 in complex with a small-molecule guest.

a Octacid4•p-xylene. b Octacid4•naphthalene. c Octacid4•1,4-dioxane. Carbon and oxygen are in blue and red, respectively. The axial or equatorial portal of Octacid4 comprises the C3 and C19 atoms or the O7, O15, C6b, and C17a atoms, respectively. Hydrogen and counter ion are not displayed for clarity.