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-[(2R)-1-(7,8-dichloro-4-imidazol-1-ylquinolin-2-yl)pyrrolidin-2-yl]acetic acid by IUPAC nomenclature, provide its molecular formula.
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C18H16Cl2N4O2
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