Aesculus hippocastanum
Aesculin, also called æsculin or esculin, is a coumarin glucoside that naturally occurs in the trees horse chestnut ("Aesculus hippocastanum"), California buckeye ("Aesculus californica"), prickly box ("Bursaria spinosa"), and daphnin (the dark green resin of "Daphne mezereum"). It is also found in dandelion coffee.