Conjunctive Nomenclature

Rule C-51

51.1 - When a side chain attached to a cyclic component of a structure carries one principal group, the name of the molecule corresponding to the cyclic component is placed before the substitutive name of the molecule corresponding to the side chain.

Example to Rule C-51.1

51.2 - When necessary, the position of the side chain is indicated by a numeral placed before the name of the cyclic component. Carbon atoms of the side chain are indicated by Greek letters proceeding from the principal group to the cyclic component, but these are used in the name only to locate substituents in the side chain. The terminal carbon atom of acids, aldehydes, and nitriles is omitted when allocating Greek positional letters.

Examples to Rule C-51.2

Note: Conjunctive nomenclature is not used when the side chain carries more than one of the principal group (see Rule C-51.1). As exceptions to this note, conjunctive nomenclature may, however, be used with the names malonic and succinic acid.

Examples to Rule C-51.2

See Recommendations'93 R-1.2.4

Conjunctive Nomenclature
Rule C-52
Rule C-53
Rule C-54
Rule C-55
Rule C-56
Rule C-57
Rule C-58


This HTML reproduction of Sections A, B and C of IUPAC "Blue Book" is as close as possible to the published version [see Nomenclature of Organic Chemistry, Sections A, B, C, D, E, F, and H, Pergamon Press, Oxford, 1979. Copyright 1979 IUPAC.] If you need to cite these rules please quote this reference as their source.

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