You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-hydroxy-6-(4-hydroxy-3-methoxyphenyl)-9-methyl-3a,4,6,11,11a,11b-hexahydronaphtho[6,7-e]isoindole-1,3,7,10-tetrone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C24H21NO7
assistant