Macrocycle

Macrocycles are often described as molecules and ions containing a ring of twelve or more atoms. Classical examples include the crown ethers, calixarenes, porphyrins, and cyclodextrins. Macrocycles describe a large, mature area of chemistry.^[2]

IUPAC definition

Macrocycle: Cyclic macromolecule or a macromolecular cyclic portion of a macromolecule. Note 1: A cyclic macromolecule has no end-groups but may nevertheless be regarded as a chain.
Note 2: In the literature, the term macrocycle is sometimes used for molecules of low relative molecular mass that would not be considered macromolecules.^[3]

^ Hamilton-Miller, JM (1973). "Chemistry and Biology of the Polyene Macrolide Antibiotics". Bacteriological Reviews. 37 (2): 166–196. doi:10.1128/br.37.2.166-196.1973. PMC 413810. PMID 4578757.
^ Zhichang Liu; Siva Krishna Mohan Nalluria; J. Fraser Stoddart (2017). "Surveying macrocyclic chemistry: from flexible crown ethers to rigid cyclophanes". Chemical Society Reviews. 46 (9): 2459–2478. doi:10.1039/c7cs00185a. PMID 28462968.
^ R. G. Jones; J. Kahovec; R. Stepto; E. S. Wilks; M. Hess; T. Kitayama; W. V. Metanomski (2008). IUPAC. Compendium of Polymer Terminology and Nomenclature, IUPAC Recommendations 2008 (the "Purple Book") (PDF). RSC Publishing, Cambridge, UK.

[1] Hamilton-Miller, JM (1973). "Chemistry and Biology of the Polyene Macrolide Antibiotics". Bacteriological Reviews. 37 (2): 166–196. doi:10.1128/br.37.2.166-196.1973. PMC 413810. PMID 4578757.

[2] Zhichang Liu; Siva Krishna Mohan Nalluria; J. Fraser Stoddart (2017). "Surveying macrocyclic chemistry: from flexible crown ethers to rigid cyclophanes". Chemical Society Reviews. 46 (9): 2459–2478. doi:10.1039/c7cs00185a. PMID 28462968.

[3] R. G. Jones; J. Kahovec; R. Stepto; E. S. Wilks; M. Hess; T. Kitayama; W. V. Metanomski (2008). IUPAC. Compendium of Polymer Terminology and Nomenclature, IUPAC Recommendations 2008 (the "Purple Book") (PDF). RSC Publishing, Cambridge, UK.

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