Large-ring Cyclodextrins

Harada, A., A. Cyclodextrins, Large Ring Molecules (Semiyen, J. A. ed.), Wiley, Chichester, 1996. 

Ueda, H. (2002) Physicochemical Properties and Complex Formation Abilities of Large-Ring Cyclodextrins, J. Incl. Phenom. 44, 53-56. 

Ueda, H (2002). Physicochemical properties and complex formation abilities of large-ring cyclodextrins. Journal of Inclusion Phenomena and Macrocyclic Chemistry,44,53 56. 

Qi, Q, X She, T Endo and W Zimmermann (2004). Effect of the reaction temperature on the transglycosylation reactions catalyzed by the cyclodextrin glucanotransferase from Bacillus macerans for the synthesis of large-ring cyclodextrins. Tetrahedron, 60,... 

Mogensen, B, T Endo, H Ueda, W Zimmermann and KL Larsen (2000). Analysis of complex formation between large-ring cyclodextrins and aromatic anions. In cydodextrin Prom Basic Research to Market. 10th International Cyclodextrin Symposium, Ann Arbor, Ml, USA CD-ROM edition. 

Table VII (51). The relevant free dimensions are often similar for zeolite and nonzeolite. Urea (free diameter 5.2 A) is like Sieve A (free diameter of windows 4.3 A) in accommodating n- but not isoparaffins. Thiourea (6.1 A) and offretite (6.3 A) have channels with similar free diameters as do 0-cyclodextrin (7-8 A) and zeolite L (7.1 X 7.8 A). In thiourea the loose fit of n-paraffins in the tunnel appears to destabilize the adducts (85, 36). The same is true of disc-shaped molecules comprising only benzenoid rings. However, if suitably bulky saturated side chains are attached (cyclohexyl-benzene or fertf-butylbenzene), then adduction readily occurs. Heterocy-clics, like unsubstituted aromatics, do not readily form adducts. Thus flat molecules also exert a destabilizing effect upon the tunnels of a circular cross section. Such stability problems do not arise with the robust, permanent zeolite structures, and this constitutes an interesting distinction. Offretite, for example, readily sorbs benzene or heterocyclics with or without alkyl side chains, provided only that they are not too large to permeate the structure.

Potential use of complexes of y - CD with organic compounds, including polymers, was also reviewed by Szejtli [6, 12, 13], y - CD are able to incorporate metal ions as ligands to prepare magnetic nano - particles [7,14], Harada and Ka-machi [8,15] first found that poly (ethylene oxide) (PEO) thread a- CD rings to form polymer - cyclodextrin complex. Since their finding of inclusion complex formation of polymer chains with a- CD, a large number of studies on inclusion complexes of... 

Seo et have shown the dependence of stability constant and overall solubility upon cyclodextrin ring size for spironolactone. From the data given in Fig. 19, it can be seen that for the relatively large spironolactone molecule (Fig. 9) the stability constant increases with size of the host cavity that is reflected through an increase in the linear slopes. The lowest maximum solubility was obtained with the p-cyclodex-trin, which has the lowest solubility of the three cyclo-dextrins. ... 

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