A @[email protected] comprising a cyclic or polycyclic assembly of @[email protected] that contains three or more binding sites held together by @[email protected], and which defines a molecular cavity in such a way as to bind (and thus 'hide' in the cavity) another molecular entity, the @[email protected] (a @[email protected], an @[email protected] or a neutral species), more strongly than do the separate parts of the assembly (at the same total concentration of binding sites). The @[email protected] thus formed is called a 'cryptate'. The term is usually restricted to bicyclic or oligocyclic molecular entities. Example:
Corresponding monocyclic ligand assemblies @[email protected] are sometimes included in this group, if they can be considered to define a cavity in which a @[email protected] can hide. The terms 'podand' and 'spherand' are used for certain specific ligand assemblies. Coplanar cyclic polydentate @[email protected], such as @[email protected], are not normally regarded as cryptands.
See also:
host (in biotechnology)
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1102 [Terms] [Paper]
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1329 [Terms] [Paper]