You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-N,2-N,3-N',3-N',6-N',6-N'-hexaethylspiro[11H-chromeno[4,3-b]indole-6,9'-fluorene]-2,3',6'-triamine into molecular formula.
user
C39H44N4O
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