There are three isomers of coumaric acids — o-coumaric acid, m-coumaric acid, and p-coumaric acid — that differ by the position of the hydroxy substitution of the phenyl group.

o-Coumaric acid can be found in vinegar.

2-Coumarate reductase is an enzyme that produces 2-coumarate from 3-(2-hydroxyphenyl)propanoate and NAD+.

This enzyme participates in phenylalanine metabolism.

This article about an aromatic compound is a stub.