You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule (2S)-2-[2-[4-[2-[cyano-[(3S)-pyrrolidine-3-carbonyl]amino]pyridin-4-yl]pyridin-2-yl]hydrazinyl]-4-methylsulfanylbutanoic acid ?
user
C21H25N7O3S
assistant