Title: constitutional sequence
Long Title: IUPAC Gold Book - constitutional sequence
DOI: 10.1351/goldbook.C01287
Status: current

Definition
The whole or part of a chain comprising one or more species of constitutional unit(s) in defined sequence.

Note
Constitutional sequences comprising two constitutional units are termed diads, those comprising three constitutional units triads, and so on. In order of increasing sequence lengths they are called tetrads, pentads, hexads, heptads, octads, nonads, decads, undecads, etc.

Related Terms
- chain: https://goldbook.iupac.org//terms/view/C00946
- constitutional unit(s): https://goldbook.iupac.org//terms/view/C01288
- sequence: https://goldbook.iupac.org//terms/view/ST06775

Source
- PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2299 (https://doi.org/10.1351/pac199668122287)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C01287/html
- json: https://goldbook.iupac.org/terms/view/C01287/json
- xml: https://goldbook.iupac.org/terms/view/C01287/xml

Citation: Citation: 'constitutional sequence' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.C01287
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Accessed: 2026-04-18T15:07:24+00:00