Term: multiply labelled
https://doi.org/10.1351/goldbook.M04063

Definition:
A selectively labelled compound may be multiply labelled when in the unmodified compound there is more than one atom of the same element at the position where the isotopic modification occurs, e.g. H in CH4, or there are several atoms of the same element at different positions where the isotopic modification occurs, e.g. C in C4H8O.

Related Terms:
1) selectively labelled (http://doi.org/10.1351/goldbook.S05556).

Source: Blue Book, p. 515 (https://www.acdlabs.com/iupac/nomenclature/)

Citation: 'multiply labelled' 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.M04063

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