You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[[(6S)-3-cyano-6-methyl-4,5,6,7-tetrahydro-1-benzothiophen-2-yl]carbamothioyl]pentanamide into molecular formula.
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C16H21N3OS2
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