You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[1-[3-(methylamino)piperidin-1-yl]-1-oxo-3-pyridin-3-ylpropan-2-yl]benzamide;dihydrochloride into its molecular formula.
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C21H28Cl2N4O2
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