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 O-[(2S)-2-[(2R,3R,4R)-3,4-dihydroxyoxolan-2-yl]-2-hydroxyethyl] pentadecanethioate is given. What is its corresponding molecular formula?
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C21H40O5S
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