You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (NZ)-4-chloro-N-[3-(2-ethoxyethyl)-4,7-dimethoxy-1,3-benzothiazol-2-ylidene]benzenesulfonamide into molecular formula.
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C19H21ClN2O5S2
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