You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 4-[5-chloro-2-(6-methylpyridin-3-yl)pyridin-3-yl]-N-methylbenzenesulfinamide;ethane by IUPAC nomenclature, provide its molecular formula.
user
C20H22ClN3OS
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