You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4E)-4-[(2,6-dimethoxyphenyl)-hydroxymethylidene]-1-(2-hydroxyphenyl)-5-(4-hydroxyphenyl)pyrrolidine-2,3-dione is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H21NO7
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