You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 4-[(4-imidazo[1,2-a]pyridin-3-ylpyrimidin-2-yl)amino]-N-(3-methoxypropyl)benzenesulfonamide into molecular formula.
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C21H22N6O3S
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