What is "fraxin"

fraxin \frax"in\, n. [From Fraxinus.] (Chem.) A colorless crystalline substance ( C16H18O10) found in the bark of the ash ( Fraxinus), and along with esculin in the bark of the horse-chestnut. It is structurally a derivative of a coumarin glucoside. It shows a delicate blue-green fluorescence in alkaline solutions; -- called also paviin and fraxoside.
--MI-11br/

Syn:

8-([beta]-D-Glucopyranosyloxy)-7-hydroxy-6-methoxy-2H-1-benzopyran-2-one; also, 7,8-dihydroxy-6-methoxy-coumarin-8-[beta]-D-glucoside; fraxetin-8-glucoside.

n. (context organic compound English) A colourless crystalline substance, regarded as a glucoside, found in the bark of the ash (''Fraxinus'') and along with esculin in the bark of the horse-chestnut. It is faintly fluorescent in alkaline solutions.