You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named N-[[2-(4-methylpiperazin-1-yl)pyridin-3-yl]methyl]-3-pyridin-3-yloxypyrrolidine-1-carboxamide is given. What is its corresponding molecular formula?
user
C21H28N6O2
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