You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 1-[(4aR,8aR)-6-(thiophen-3-ylmethyl)-2,3,4,4a,5,7,8,8a-octahydro-1,6-naphthyridin-1-yl]-2-phenylsulfanylethanone into molecular formula.
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C21H26N2OS2
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