Corands as ATPase mimics

8 Hosseini, M. W., Supramolecular catalysis of phosphoryl anion transfer processes , in Supramolecular Chemistry of Anions, Bianchi, A., Bowman-James, K., Garcia-Espana, E., eds. Wiley New York, 1997 pp 421-448. 

The X-ray crystal structure of the hexachloride salt of the protonated macrocycle shows that it adopts a cleft-like conformation as shown in the diagram, and modelling studies support the existence of this conformation in solution. The electrostatic nature of the anion binding by 4.12-nH+ means that it binds particularly strongly to multiply changed anions, and ATP, with its 4- charge, is bound in water at pH 4, with logXn = 11 for the hexaprotonated host. 

9 (which has been isolated), step C. Alternatively, reaction of the P—N bond in the ADP complex with water (step E) followed by displacement of ADP by ATP (step D) could also occur. 

8 Cram, D. J. and Cram, J. M. Container Molecules and their Guests, Royal Society of Chemistry Cambridge, 1994, 65-77. 

---

Why do you think corand 4.12 ([24]aneN602) is such an effective ATPase mimic given the discussion of the relatively low affinity for guest species such as alkali metal cations and halide anions set out in Chapters 3 and 4 Similarly, why was a hemispherand chosen as the central cation-binding core of enzyme mimic 12.16 as opposed to a spherand ... 

---