You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named S-[2-[[2-[3-[(6-hydrazinylpyridin-3-yl)methyl]-1-hydroxy-2,5-dioxopyrrolidin-3-yl]-2-oxoethyl]amino]-2-oxoethyl] benzenecarbothioate by IUPAC nomenclature, provide its molecular formula.
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C21H21N5O6S
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