Term: crown
https://doi.org/10.1351/goldbook.C01421

Definition:
A molecular entity comprising a monocyclic ligand assembly that contains three or more binding sites held together by covalent bonds and capable of binding a guest in a central (or nearly central) position. The adducts formed are sometimes known as 'coronates'. The best known members of this group are macrocyclic polyethers, such as '18-crown-6', containing several repeating units –CR2–CR2O– (where R is most commonly H), and known as crown ethers. C01421.png

Related Terms:
1) host (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.H02859).
2) molecular entity (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.M03976).
3) binding sites (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.B00649).
4) adducts (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.A00138).
5) guest (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.G02711).
6) ethers (<em>in biotechnology</em>) (http://doi.org/10.1351/goldbook.E02221).

Image: Not defined (https://goldbook.iupac.org/img/inline/C01421.png) 

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1101 (https://doi.org/10.1351/pac199466051077)

Citation: 'crown' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C01421

License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.

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