umbelliferone

Umbelliferone, also known as 7-hydroxycoumarin, is a naturally occurring hydroxycoumarin and a member of the coumarin family. Its core structure is a benzopyranone with a hydroxyl group at the 7-position.

It is widely distributed in the plant kingdom, with reports in several families, including Apiaceae (carrot, celery, fennel) and Rutaceae (citrus). In plants, umbelliferone is produced via the phenylpropanoid pathway and is formed through enzymatic steps that lead to hydroxycinnamoyl derivatives and their lactonization into the coumarin ring.

Chemically, umbelliferone is a small aromatic lactone that is soluble in organic solvents and sparingly soluble in water. It absorbs ultraviolet light, with excitation typically in the 320–360 nm range and emission in the blue region around 440–450 nm, giving it notable blue fluorescence under UV illumination.

Uses of umbelliferone are mainly in research and analytical contexts. It serves as a fluorescent reagent and calibration standard in fluorometric assays and spectroscopy. It is also employed in studies of plant metabolism and the phenylpropanoid pathway, where its formation and properties help illuminate biosynthetic processes in plants.

Synonyms for the compound include 7-hydroxycoumarin, and it is related to other natural coumarins such as scopoletin and esculetin.