You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (12S,17R)-17-(4-chlorophenyl)-11-oxa-16-azatetracyclo[8.7.0.02,7.012,16]heptadeca-1(10),2,4,6,8-pentaene is given. What is its corresponding molecular formula?
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C21H18ClNO
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