You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-O-methyl 4-O-[3-[(5-oxopyrrolidine-2-carbonyl)amino]propyl] (E)-but-2-enedioate by IUPAC nomenclature, provide its molecular formula.
user
C13H18N2O6
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