You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[5-[(3S,5S)-3,5-dimethylpiperidine-1-carbonyl]-2-methylphenyl]-1-oxidopyridin-1-ium-2-carboxamide into its molecular formula.
user
C21H25N3O3
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