Parent chain

In IUPAC nomenclature, a parent structure, parent compound, parent name or simply parent is the denotation for a compound consisting of an unbranched chain of skeletal atoms (not necessarily carbon), or consisting of an unsubstituted monocyclic or polycyclic ring system. Parent structures bearing one or more functional groups that are not specifically denoted by a suffix are called functional parents. Names of parent structures are used in IUPAC nomenclature as basis for systematic names.

A parent hydride is a parent structure with one or more hydrogen atoms. Parent hydrides have a defined standard population of hydrogen atoms attached to a skeletal structure. Parent hydrides are used extensively in organic nomenclature, but are also used in inorganic chemistry.

To construct a systematic name, affixes are attached to the parent name, which denote substituents that replace hydrogen.

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