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-[1-tert-butyl-3-(2-methylpropyl)-2-oxo-1-[2-oxo-2-(pyridin-4-ylamino)ethyl]pyrrolidin-1-ium-3-yl]-N-hydroxyacetamide into molecular formula.
user
C21H33N4O4+
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