You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-ethoxy-4-[(Z)-[3-(2-methylpropyl)-2,4-dioxo-1,3-thiazolidin-5-ylidene]methyl]phenoxy]acetate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H20NO6S-
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