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-[(2S)-1-hydroxy-3-(1H-indol-3-yl)propan-2-yl]-1-phenylmethanesulfonamide is given. What is its corresponding molecular formula?
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C18H20N2O3S
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