Term: main chain (backbone)
https://doi.org/10.1351/goldbook.M03694

Definition:
That linear chain to which all other chains, long or short or both, may be regarded as being pendant.

Note: Where two or more chains could equally be considered to be the main chain, that one is selected which leads to the simplest representation of the molecule.

Related Terms:
1) linear chain (http://doi.org/10.1351/goldbook.L03546).
2) chains, long (http://doi.org/10.1351/goldbook.L03619).
3) short (http://doi.org/10.1351/goldbook.S05647).

Source: PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2294 (https://doi.org/10.1351/pac199668122287)

Citation: 'main chain (backbone)' 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.M03694

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