Inclusion host-guest, molecular

The formation of host-guest inclusion compounds in crystals (or in highly ordered membranes or other biological structures) is a phenomenon more organised than simple co-crystallisation of a pair of substances. The special characteristic of inclusion crystallisation is a constant identity of one member in a series of pairs, this member thereby being identified as host, and a constancy of structure type (but not necessarily dimensions) for the host. The higher molecular organisation involved in inclusion... 

Host-guest inclusion complexes, 262—263 antibiotic hosts, 231—233 cahxarene hosts, 228—231 chiral crown ether hosts, 213—218 cyclic oligosaccharide hosts, 218—222 cyclodextrin host selectivities, 223/ host molecular size, 221 hnear ohgosaccharide hosts, 222—228 ir- TT stacking interactions, 217 proteic hosts, 231 Human 15-hpoxygenase, 52/... 

HORN-BORNIG PLOT HORSERADISH PEROXIDASE HOST-GUEST INTERACTIONS HOST MOLECULE CROWN ETHERS MACROCYCLES INCLUSION COMPLEXES HOCKEL MOLECULAR-ORBITAL CALCULATIONS... 

Native enzymes show remarkably sharp substrate specificities. Actually, an enzyme can sometimes distinguish a slight difference of shapes between its specific and nonspecific guests, even if the electronic states of both are almost the same. The term molecular recognition is used to describe such ability of the molecule (enzyme). Inclusion compounds are supersimplified, but very appropriate systems for elucidation of the nature of the molecular recognition, since interactions between the inclusion host and a substrate are not more complicated than can be measured or even calculated. In this section, we will survey the recent results on the crystal structures of the inclusion compounds, and based on the information, the probable driving force for the inclusion is discussed in detail. 

The cage-type cyclophane furnishes a hydrophobic internal cavity for inclusion of guest molecules and exercises marked chiral discrimination in aqueous media. The host embedded in the bilayer membrane is capable of performing effective molecular recognition as an artificial cell-surface receptor to an extent comparable to that demonstarated by the host alone in aqueous media. 

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