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 2-(4-methylphenyl)-5-(4-phenylpiperazin-1-yl)sulfonyl-1,3-oxazole-4-carbonitrile is given. What is its corresponding molecular formula?
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C21H20N4O3S
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