You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N-[(2S)-4-amino-3,4-dioxo-1-phenylbutan-2-yl]-2-phenylthiophene-3-carboxamide is given. What is its corresponding molecular formula?
user
C21H18N2O3S
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