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 2-ethoxy-4-[(2R,5R,6S)-2-methyl-6-pyridin-2-yl-2,3,5,6-tetrahydroimidazo[2,1-b][1,3]thiazol-5-yl]phenol into molecular formula.
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C19H21N3O2S
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