You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named methyl 3-ethyl-2-[2-(4-ethylphenyl)acetyl]imino-1,3-benzothiazole-6-carboxylate is given. What is its corresponding molecular formula?
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C21H22N2O3S
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