You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (6-methylpyridin-2-yl)-[(3S)-3-[1-(pyridin-3-ylmethyl)imidazol-2-yl]piperidin-1-yl]methanone into molecular formula.
user
C21H23N5O
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