You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (10S,11Z)-14-ethyl-13,16-dimethyl-9-oxa-16-azatetracyclo[8.5.1.11,5.04,8]heptadeca-2,7,11-triene into its molecular formula.
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C19H27NO
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