You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-[[4-amino-6-(2-methylanilino)-1,3,5-triazin-2-yl]methylsulfanyl]-N,N-dimethylpyridine-3-sulfonamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H21N7O2S2
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