You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-ethoxy-4-[(3R,5S,6R)-3-ethyl-6-pyridin-2-yl-2,3,5,6-tetrahydroimidazo[2,1-b][1,3]thiazol-5-yl]-6-nitrophenol into its molecular formula.
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C20H22N4O4S
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