You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1E)-3-acetyl-1-[(3,4-dimethyl-5-oxo-2H-furan-2-yl)oxymethylidene]-4,8b-dihydro-3aH-indeno[2,1-b]pyrrol-2-one The above is the IUPAC name of a molecule. Write its molecular formula.
user