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 [2-[(9,10-dioxoanthracen-1-yl)amino]-2-oxoethyl] 5-chlorothiophene-2-carboxylate is given. What is its corresponding molecular formula?
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C21H12ClNO5S
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