Side chain

This article is about the chemistry term. For the audio engineering term, see dynamic range compression.

A side chain in organic chemistry and biochemistry is a part of a molecule that is attached to a core structure. An R group is a generic label for a side chain which can be anything; however, it is typically stable and covalently linked to the adjoining atom. Historically the abbreviations R and R-group, which often refer to side chains, come from the word "radical" or "rest".

See also

• Functional group