You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(2,3-dihydroindol-1-yl)-2-(2-methyl-2,3-dihydro-1,4-benzothiazin-4-yl)ethanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H20N2OS
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