Formula	CAS
C9H6O2	91-64-5

Background
Coumarin (2H-chromen-2-one) is a fragrant chemical compound in the benzopyrone chemical class, found in many plants, notably in high concentration in the tonka bean (Dipteryx odorata), vanilla grass (Anthoxanthum odoratum), sweet woodruff (Galium odoratum), mullein (Verbascum spp.), sweet grass (Hierochloe odorata), cassia cinnamon (Cinnamomum aromaticum) and sweet clover (Fabaceae spp.). The name comes from a French word, coumarou, for the tonka bean. It has a sweet odor, readily recognised as the scent of newly-mown hay, and has been used in perfumes since 1882. Sweet woodruff, sweet grass and sweet clover in particular are named for their sweet smell, which is due to their high content of this substance. It has been used as an aroma enhancer in pipe tobaccos and certain alcoholic drinks, although in general it is banned as a flavorant food additive, due to concerns about hepatotoxicity coumarin causes in animal models. When it occurs in high concentrations in forage plants, coumarin is a somewhat bitter-tasting appetite suppressant, and is presumed to be produced by plants as a defense chemical to discourage predation. Although coumarin itself has no anticoagulant properties, it is transformed into the natural anticoagulant dicoumarol by a number of species of fungi. This occurs as the result of the production of 4-hydroxycoumarin, then further (in the presence of naturally occurring formaldehyde) into the actual anticoagulant dicoumarol, a fermentation product and mycotoxin. This substance was responsible for the bleeding disease known historically as "sweet clover disease" in cattle eating moldy sweet clover silage.

Coumarin is part of the Fragrance II mix.

Synonyms
2H-chromen-2-one
1-benzopyran-2-one

Uses
Perfumes
Cosmetics
Gain medium in some dye lasers
Photovoltaic technologies

Back to list of contact allergens


Author(s):
Allergology: background information on allergens.