You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule methyl 3-[5-[2-cyano-3-(diethylamino)-3-oxoprop-1-enyl]-2-hydroxy-3-nitrophenoxy]carbonyloxybutanoate into molecular formula.
user
C20H23N3O9
assistant