You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[5-methyl-4-[(2R)-2-methyl-3-oxo-4H-1,4-benzoxazin-6-yl]-1,3-thiazol-2-yl]-3-phenylpropanamide into its molecular formula.
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C22H21N3O3S
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