You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (3R)-N-[11-(1-acetyl-3-oxo-4H-imidazo[4,5-c]pyrazol-2-yl)undecyl]-2-amino-3-hydroxybutanamide into its molecular formula.
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C21H36N6O4
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