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 2-[3-[[4-(cyclobutylmethyl)-7H-pyrrolo[2,3-d]pyrimidin-2-yl]amino]phenoxy]-N-methylacetamide .
user
C20H23N5O2
assistant