You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,2S)-11,14-diazahexacyclo[12.8.0.02,11.03,8.04,21.017,22]docosa-3,5,7,17,19,21-hexaene-5,6,19,20-tetrol is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H20N2O4
assistant