You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (Z)-2-[[5-(5-chloro-2-methoxyphenyl)-1,3,4-oxadiazol-2-yl]sulfanyl]-3-[4-(cyanomethoxy)-3-methoxyphenyl]prop-2-enoic acid by IUPAC nomenclature, provide its molecular formula.
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C21H16ClN3O6S
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