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In supramolecular chemistry, [1] host–guest chemistry describes complexes that are composed of two or more molecules or ions that are held together in unique structural relationships by forces other than those of full covalent bonds. Host–guest chemistry encompasses the idea of molecular recognition and interactions through non-covalent ...
In chemistry, a cavitand is a container-shaped molecule. [2] The cavity of the cavitand allows it to engage in host–guest chemistry with guest molecules of a complementary shape and size. The original definition proposed by Cram includes many classes of molecules: cyclodextrins , calixarenes , pillararenes and cucurbiturils . [ 3 ]
Static molecular recognition is likened to the interaction between a key and a keyhole; it is a 1:1 type complexation reaction between a host molecule and a guest molecule to form a host–guest complex. To achieve advanced static molecular recognition, it is necessary to make recognition sites that are specific for guest molecules.
Crystal structure of a nitrobenzene bound within a hemicarcerand reported by Cram and coworkers in Chem. Commun., 1997, 1303-1304.. In host–guest chemistry, a carcerand (from Latin carcer 'prison') is a host molecule that completely entraps its guest (which can be an ion, atom or other chemical species) so that it will not escape even at high temperatures. [1]
In cooperativity, the initial ligand binding affects the host's affinity for subsequent ligands. In positive cooperativity, the first binding event enhances the affinity of the host for another ligand. Examples of positive and negative cooperativity are hemoglobin and aspartate receptor, respectively. [10] General Host–Guest Binding. (1.)
Police in Ohio are searching for suspects after a 19-year-old woman was stripped of her clothes and attacked last month.. The Akron Police Department in Ohio told PEOPLE in a statement that ...
The three-dimensional interior cavity of a cryptand provides a binding site – or host – for "guest" ions. The complex between the cationic guest and the cryptand is called a cryptate. Cryptands form complexes with many "hard cations" including NH + 4, lanthanoids, alkali metals, and alkaline earth metals.
Chemists have long been interested in mimicking chemical processes in nature. Coordination cages quickly became a hot topic as they can be made by self-assembly, a tool of chemistry in nature. [4] The conceptualization of a closed-surface molecule capable of incorporating a guest was described by Donald Cram in 1985. [5]