Principles of Organic Nomenclature

R-1.2.5 Subtractive operation

The subtractive operation involves the removal of an atom, ion, or group implicit in a name. This can occur with no other change, with exchange for hydrogen, with introduction of unsaturation, or with bond scission and reformation. The elimination of the elements of water with concomitant bond formation can also be regarded as a subtractive operation. Subtraction can be expressed in the following ways:

R- By use of a prefix

Examples to R-

Oxytocin Des-7-proline-oxytocin
(here the prefix "des-" signifies removal of the proline residue at position 7 of the polypeptide oxytocin, with rejoining of the chain) (see also Ref. 1, Section F).

R- By a change in ending or addition of a suffix

Examples to R-

R-1.2.6 Ring formation or cleavage
R-1.2.7 Rearrangement
R-1.2.8 Multiplicative operation

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

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