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 4-methyl-N-[[(3S,6'R)-2-oxo-6'-propylspiro[1H-indole-3,2'-oxane]-4'-ylidene]amino]benzenesulfonamide into molecular formula.
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C22H25N3O4S
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