You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[(1R,3R,6R)-3-ethyl-7-(7H-pyrrolo[2,3-d]pyrimidin-4-ylamino)-2-azabicyclo[4.1.0]heptan-2-yl]prop-2-en-1-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C17H21N5O
assistant