You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-[[4-(2,5-difluorophenyl)sulfanyl-5,6-dimethylthieno[2,3-d]pyrimidin-2-yl]methyl]morpholin-4-ium into its molecular formula.
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C19H20F2N3OS2+
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