You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[5-[(3,4-dimethoxy-5-prop-2-enylphenyl)methylidene]-4,6-dioxo-2-sulfanylidene-1,3-diazinan-1-yl]benzoic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H20N2O6S
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