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 1-[4-[1-(4-methyl-1,3-thiazole-5-carbonyl)piperidin-2-yl]piperidin-1-yl]-2-(2-methyl-1,3-thiazol-4-yl)ethanone into molecular formula.
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C21H28N4O2S2
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