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 N-[(R)-(4-chlorophenyl)-(1-methylimidazol-2-yl)methyl]-2-[2-(2-oxopyrrolidin-1-yl)-1,3-thiazol-4-yl]acetamide is given. What is its corresponding molecular formula?
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C20H20ClN5O2S
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