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-[6-chloro-4-(4,5-difluoro-1,3-benzothiazol-2-yl)-4-methyl-3-oxo-1,4-benzoxazin-4-ium-2-yl]acetic acid into molecular formula.
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C18H12ClF2N2O4S+
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