You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[(2R,6R)-2,6-dimethylmorpholin-4-yl]-1-[(3S)-3-phenyl-2,3-dihydro-1,4-benzoxazin-4-yl]ethanone by IUPAC nomenclature, provide its molecular formula.
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C22H26N2O3
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