Chain compounds - Sashikibagobu

Also called acyclic compounds. A general term for compounds that do not contain a cyclic atomic arrangement within the molecule. Within the molecule of a chain compound, the longest carbon chain is considered to be the base, and is called the main chain. Carbon chains that branch off from the main chain are called side chains. However, branches that begin with heteroatoms or carbonyl groups are considered functional groups and are not called side chains. Chain compounds that do not have side chains are called straight chains. Chain compounds can also be thought of as aliphatic hydrocarbons such as alkanes and alkenes, and their derivatives.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

非環式化合物ともいう．分子内に環状の原子配列の構造を含まない化合物の総称．鎖式化合物の分子内で，もっとも長い炭素鎖を基本と考え，これを主鎖という．主鎖に対する枝分れ炭素鎖を側鎖という．ただし，ヘテロ原子やカルボニル基にはじまる枝分れは官能基とみなし，側鎖とはいわない．側鎖をもたない鎖式化合物を直鎖という．鎖式化合物はアルカン，アルケンなどの脂肪族炭化水素，およびその誘導体と考えることもできる．

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