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 (6S)-2-[(2-hydroxynaphthalen-1-yl)methylideneamino]-6-methyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile into molecular formula.
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C21H18N2OS
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