You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 10-(5-chloropent-1-ynyl)-14-oxa-7-azatetracyclo[6.6.1.01,11.02,7]pentadeca-9,11-dien-13-one into its molecular formula.
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C18H20ClNO2
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