You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 2-[(3S,6S)-4-(4-methylphenyl)sulfonyl-3-(2-methylpropyl)-1-oxa-4,8-diazaspiro[5.5]undecan-8-yl]-N-[4-(4-methylphenyl)-1,3-thiazol-2-yl]acetamide into molecular formula.
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C31H40N4O4S2
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