Synthetic or naturally occurring substances related to coumarin, the delta-lactone of coumarinic acid.

Synonyms: Benzopyran 2 ones, Derivative, Coumarin, 1,2-Benzo-Pyrones, Coumarins, Coumarin Derivative, 1,2 Benzo Pyrones, 1,2 Benzopyrones, Coumarin Derivatives, 0, Benzopyran-2-ones, 1,2-Benzopyrones, 1,2 Benzopyrone Derviatives, Coumarine, Derivatives, Coumarin, Coumarines, 1,2-Benzopyrone Derviatives, Derviatives, 1,2-Benzopyrone