Scopoletin is a coumarin found in the root of plants in the genus Scopolia such as Scopolia carniolica and Scopolia japonica, in chicory, in Artemisia scoparia, in the roots and leaves of stinging nettle (Urtica dioica), in the passion flower, in Brunfelsia, in Viburnum prunifolium, in Solanum nigrum, in Datura metel, in Mallotus resinosus, or and in Kleinhovia hospita. It can also be found in fenugreek, vinegar, some whiskies or in dandelion coffee. A similar coumarin is scoparone. Scopoletin is highly fluorescent when dissolved in DMSO or water and is regularly used as a fluorimetric assay for the detection of hydrogen peroxide in conjunction with horseradish peroxidase. When oxidized, its fluorescence is strongly suppressed. Chemistry Biosynthesis Like most phenylpropanoids, the biosynthetic precursor to scopoletin acid is 4-coumaroyl-CoA. Scopoletin is derived from 1,2-benzopyrones which is the core structure of coumarins formed through hydroxylation of cinnamates, trans/cis isomerization of the side chain, and lactonization. And CYP98A (C3’H) are enzymes belonging to the cytochrome P450 family that catalyze the meta-hydroxylation of p-coumarate derivatives, an important step in the phenylpropanoid pathway. For scopoletin, most of biosynthetic investigations are based on Arabidopsis thaliana. Derivatives/Related Compounds Scopolin is a glucoside of scopoletin formed by the action of the enzyme scopoletin glucosyltransferase. Uses Traditional Medicine It was usually used for rheumatic arthritis therapy in Traditional Chinese Medicine. References O-methylated coumarins