You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(8-hydroxyimino-4,13,14,15-tetramethoxy-5-tricyclo[9.4.0.02,7]pentadeca-1(15),2,4,6,11,13-hexaenyl) methyl carbonate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H23NO8
assistant