You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 3-methyl-5-[8-oxo-5-[4-(2-oxobutyl)phenyl]-6-sulfanylidene-5,7-diazaspiro[3.4]octan-7-yl]pyridine-2-carbonitrile .
user
C23H22N4O2S
assistant