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 3-(4-chlorophenyl)-1-(3-methylphenyl)-2,5,6,7-tetrahydroimidazo[2,1-b][1,3]thiazin-4-ium-3-ol;bromide is given. What is its corresponding molecular formula?
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C19H20BrClN2OS
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