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-[(1R)-1-[1-[(2S)-3-(4-chlorophenoxy)-2-hydroxypropyl]benzimidazol-2-yl]ethyl]acetamide is given. What is its corresponding molecular formula?
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C20H22ClN3O3
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