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-[2-[5-[3-(carboxymethyl)-5-(5-methoxycarbonylthiophen-2-yl)thiophen-2-yl]thiophen-2-yl]-5-(5-methoxycarbonylthiophen-2-yl)thiophen-3-yl]acetic acid is given. What is its corresponding molecular formula?
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C28H20O8S5
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