You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl (7R)-7-(4-methoxyphenyl)-5-methyl-3-oxo-7H-[1,3]thiazolo[3,2-a]pyrimidine-6-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C17H18N2O4S
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