You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[2-[(4S,6R)-2-amino-4,6-dimethyl-5,6-dihydro-1,3-thiazin-4-yl]pyridin-4-yl]-5-(fluoromethoxy)pyridine-2-carboxamide into its molecular formula.
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C18H20FN5O2S
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