You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[2-[[2-(2-aminopropanoylamino)-3-(1H-indol-3-yl)propanoyl]amino]-3-(1H-imidazol-5-yl)propanoyl]amino]acetic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H27N7O5
assistant