You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2,3,4,5-tetrachloro-6-[[4-[2-(4-methoxyphenyl)-2-oxoethyl]sulfanylphenyl]carbamoyl]benzoic acid by IUPAC nomenclature, provide its molecular formula.
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C23H15Cl4NO5S
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