You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[cyanomethyl-[[(2E)-6-hydroxy-2-[(3-nitrophenyl)methylidene]-3-oxo-1-benzofuran-7-yl]methyl]amino]acetonitrile into molecular formula.
user
C20H14N4O5
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