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-(benzimidazol-1-yl)-N-[(2S)-1-(2-chlorophenyl)propan-2-yl]propanamide is given. What is its corresponding molecular formula?
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C19H20ClN3O
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