The
phenylpropanoids are a diverse family of organic compounds that are synthesized by plants from the
amino acid phenylalanine. Their name is derived from the six-carbon, aromatic phenyl group and the three-carbon propene tail of
cinnamic acid, which is synthesized from phenylalanine in the first step of
phenylpropanoid biosynthesis. Phenylpropanoids are found throughout the plant kingdom, where they serve as essential components of a number of structural polymers, provide protection from
ultraviolet light, defend against
herbivores and
pathogens, and mediate plant-
pollinator interactions as floral pigments and scent compounds. Concentrations of phenylpropanoids within plants are also altered by changes in resource availability.