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 3-phenyl-2-(4-propan-2-yloxyphenyl)sulfonyl-1,3,5,6,7,7a-hexahydropyrrolo[1,2-c]imidazole is given. What is its corresponding molecular formula?
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C21H26N2O3S
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