You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name formic acid;2-pyridin-3-yl-N-[(1-thieno[3,2-d]pyrimidin-4-ylpiperidin-4-yl)methyl]acetamide into its molecular formula.
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C20H23N5O3S
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