You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name phenyl-(5-pyridin-4-yl-8-thia-4,6,11-triazatricyclo[7.4.0.02,7]trideca-1(9),2,4,6-tetraen-11-yl)methanone into its molecular formula.
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C21H16N4OS
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