In contrast to 1 and 2, macrocycles 3 and 4, consisting of four X units, adopt boat conformations, with all the OH groups positioned at  = 180 and engaged in intramolecular hydrogen bonds with -NO2 groups. Although X (the building block of 3 and 4) has ESP values similar to XI (the building block of 1 and 2), the geometrical features of the macrocycles 3 and 4 preclude convergence and reduce the overall dipole moments. Both effects are responsible for low and scattered ESP values in 3 and 4, making them less promising as anion receptors.