You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 1-[9-[(4-chlorophenyl)methyl]-3,4-dihydro-2H-thiopyrano[2,3-b]indol-4-yl]-N,N-dimethylmethanamine .
user
C21H23ClN2S
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