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 11-(4-chlorophenyl)sulfonyl-3-pyrimidin-5-yl-7,11-diazatricyclo[7.3.1.02,7]trideca-2,4-dien-6-one into molecular formula.
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C21H19ClN4O3S
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