You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the compound with this IUPAC name 2-(3,4-dihydroxyphenyl)-3,5-dihydroxy-10-quinolin-4-yl-9,10-dihydropyrano[2,3-h]chromene-4,8-dione ?
user
C27H17NO8
assistant