pkoumaroyyl

Pkoumaryl (often encountered as pkoumaroyl in some texts) denotes the hydroxycinnamoyl acyl radical derived from p-coumaric acid, used in chemical nomenclature to describe the para-coumaroyl moiety in esters and amides. The prefix p- indicates the hydroxy group on the benzene ring is at the para position, and the suffix -yl marks a substituent radical. In many English sources the group is written as p-coumaroyl, but pkoumaryl appears in discussions of structure and in transliterations of non-English literature.

In biochemistry and plant chemistry, pkoumaroyl groups are formed and transferred by acyltransferases using pkoumaroyl-CoA (the activated donor) and can be attached to sugars, phenolics, or flavonoid frameworks to give pkoumaroyl esters. Common examples include pkoumaroylquinic acids and pkoumaroyl esters of various phenolics. These esters are discussed within the broader context of hydroxycinnamoyl chemistry that arises from the phenylpropanoid pathway.

Biological relevance and properties: pkoumaroyl esters contribute to the diversity of plant polyphenols, influence cell wall interactions, and participate in plant defense. The para-hydroxy group enables further reactions, including potential oxidative coupling and interactions with other phenolic units. Enzymatic hydrolysis can release the corresponding p-coumaric derivatives and the aglycone component.

See also: p-Coumaric acid, coumaroyl group, hydroxycinnamoyl esters, BAHD acyltransferases.