You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[6-(4-methylphenyl)-2-oxo-10-thia-1,5,6,8-tetrazatricyclo[7.3.0.03,7]dodeca-3(7),4,8-trien-12-yl]-N-pyridin-4-ylacetamide by IUPAC nomenclature, provide its molecular formula.
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C21H18N6O2S
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