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 (2R)-2-(5-methoxy-1H-indol-3-yl)-2-[4-[5-(trifluoromethyl)pyridin-2-yl]piperazin-1-yl]acetic acid is given. What is its corresponding molecular formula?
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C21H21F3N4O3
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