You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1R,1'R,10S,12S,13S,14'S,15R,15'S,17'R,20R,23'R)-12,14'-diethylspiro[14-oxa-8,17-diazahexacyclo[10.7.1.01,9.02,7.013,15.017,20]icosa-2,4,6,8-tetraene-10,10'-16-oxa-8,19-diazaheptacyclo[10.9.1.11,14.02,7.08,22.015,17.019,23]tricosa-2,4,6,12(22)-tetraene] The above is the IUPAC name of a molecule. Write its molecular formula.
user
C40H44N4O2
assistant