purpurin

noun

pur·​pu·​rin ˈpər-pyə-rən 

1

: an orange or red crystalline compound C₁₄H₈O₅ obtained from madder root along with alizarin or by oxidation of alizarin and used in dyeing

2

also purpurine

-rən, -ˌrēn 

: any of various colored compounds obtained from chlorophyll or related compounds by the action of cold alcoholic alkali and oxygen