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 1-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-2-[2-(pyridin-2-ylamino)-1,3-thiazol-4-yl]ethanone is given. What is its corresponding molecular formula?
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C21H22N4O3S
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