You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(E)-2-[4-[ethylsulfonyl(methyl)amino]-2-sulfophenyl]ethenyl]-5-(methanesulfonamido)benzenesulfonic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H22N2O10S4
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