You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (4S)-2-amino-6-benzyl-4-(3,4-dimethoxyphenyl)-5,5-dioxo-4H-pyrano[3,2-c][2,1]benzothiazine-3-carbonitrile by IUPAC nomenclature, provide its molecular formula.
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C27H23N3O5S
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