You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as 4-[[(1E)-1-(6-acetyl-7,9-dihydroxy-8,9b-dimethyl-1,3-dioxodibenzofuran-2-ylidene)ethyl]amino]butanoic acid using the IUPAC nomenclature.
user
C22H23NO8
assistant