Molecular hosts cyclodextrin

CB[n] are arguably the best of the families of molecular hosts (cyclodextrins, caUxarenes, cavitands...) for utilization as nanoreactors, due to their favorable properties. They contain rigid (for n < 8), spherical-shaped cavities, with... 

There are several types of natural and synthetic molecular hosts, such as cyclodextrin and cyclophane, that are shaped to accommodate neutral and charged organic molecules in the three-dimensional cavity. The inclusion complexation by molecular hosts is driven by various weak forces like van der Waals, hydrophobic, hydrogen bonding, ion-dipole, and dipole-dipole interactions, and therefore the molecular recognition process seems much more complicated. In expanding the scope of the present theory, it is intriguing and inevitable to perform the extrather-... 

In these solid inclusion componnds, the association of host and guest components is strictly a solid state phenomenon, and the examples covered in this chapter focns almost entirely on solid inclnsion componnds of this type. However, it is relevant to note that there is also another class of inclnsion compound in which the host is a molecnle containing an appropriate cavity or binding site that can inclnde gnest molecules. Such molecular host-guest complexes generally exist as associated entities both in the solntion state and in the crystalline state, and thns the incln-sion phenomenon is not exclusively a property of the solid state. Examples of host molecules of this type are crown ethers, cyclodextrins, cryptands, and calixarenes. 

Our studies of the molecular host-guest interactions are primarily directed toward understanding the cyclodextrin inclusion effect on die molecular motion, local electron density and molecular relaxkioa... 

The turbine type of helicity in canals is a toroidal turbine, and can occur with proper rotation axes and with 2V 42, 63 screw axes, and depends on the object rotated. It is necessary that a distinctive principal plane or axis of the host molecule or molecular fragment be canted in the cylindrical surface of the canal so that it is neither parallel to or perpendicular to the axis of the canal. No unequivocal instance of this type of helical canal has been reported. The cyclodextrin unimolecular hosts 3 4) might be... 

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