You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-ethoxy-N-[4-[(4-pyridin-2-ylpiperazin-1-yl)methyl]-1,3-thiazol-2-yl]pyridine-4-carboxamide into its molecular formula.
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C21H24N6O2S
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