You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 9-(2-chloro-4-fluoro-5-methylanilino)-[1,3]thiazolo[5,4-f]quinazoline-2-carboximidate is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H13ClFN5OS
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