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. The placeholder R is often used as a generic placeholder for side chains, the R historically being derived from radical or rest. In polymers the side chains extend from a backbone structure. In proteins composed of amino acids the side chains are attached to the alpha-carbon atoms of the amide backbone.

See also

• Functional group