You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(2R)-1-[[(2S)-1-[[(2S)-3-methyl-1-oxobutan-2-yl]amino]-1-oxopropan-2-yl]amino]-1-oxo-3-pyridin-4-ylpropan-2-yl]benzamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C23H28N4O4
assistant